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De waardige prior van het klooster ontving den vermoeiden avonturier met ware, broederlijke vriendelijkheid. Hij was geheel en al overtuigd geworden, dat Columbus' plannen verstandig waren, en de dadelijke en ernstige aandacht van het Spaansche hof verdienden. Toen hij de zekerheid had, dat Columbus over een bezoek aan Frankrijk dacht, ontwaakte zijn vaderlandsliefde en maakte hij zich zeer beangst, dat Spanje den roem van de groote onderneming derven zou. Dadelijk liet hij den geleerden arts ontbieden, van wien wij vroeger spraken, en deelde hem zijn vrees mee. Ook werden vele andere invloedrijke vrienden uitgenoodigd, om met Columbus over die allergewichtigste zaak te beraadslagen, welke den prior voorkwam zoo belangrijk voor den roem van Spanje te zijn.

In de nabijheid woonde een heer, die om zijn familie, zijn groot vermogen en zijn bekendheid met zeezaken vermaard was. Deze man heette Martin Alonzo Pinzon en was door zijn ondervinding in staat, om de kracht van de door Columbus aangevoerde gronden naar waarde te schatten. Met vuur omhelsde hij zijn zaak, en beloofde hem niet alleen geldelijken bijstand, maar tevens zijn invloed, om de zaak nog eens weer voor hunne majesteiten Ferdinand en Isabella te brengen. De prior van het klooster was in vroegere jaren kapellaan van de koningin geweest. Hij schreef haar een dringenden brief, en beweerde, dat Spanje zulk een schoone gelegenheid niet mocht verliezen, om boven alle landen uit te steken.

In die dagen kende men nog geen postwagens en evenmin de gemakken, die de post nu geeft. Een ouden afgeleefden zeeman werd de brief toevertrouwd, en dien zond men naar Santa F?, waar het hof, tijdens het beleg van Granada, toen verblijf hield. De afstand bedroeg ongeveer 150 mijlen. De bode kwam er goed en wel aan, en overhandigde den brief aan de koningin.

Niettegenstaande al de zorgen, welke toen haar geest vervulden, kreeg Isabella er een diepen indruk van. Zij gaf een bemoedigend antwoord mede, en drong er sterk op aan, dat haar geachte vriend, de prior van het klooster, dadelijk bij haar zou komen.

Dit antwoord verlevendigde aanstonds weer de hoop in 't hart van Columbus, en bracht groote vreugde in den kleinen kring te La Rabida. Het was midden in den winter, en koude winden woeien over de naakte bergen en kale vlakten, ook van zuidelijk Spanje. Maar onverwijld besteeg de prior den muilezel, en sukkelde langs den eenzamen weg voort naar het hof.

Hartelijk zelfs mocht de ontvangst heeten, die de koningin haar vroegeren kapellaan bereidde. Ofschoon zij teruggetrokken was en zich niet uitliet, sluimerde er onder dat koele uiterlijk warme genegenheid. Zij luisterde met instemming naar de woorden van den prior. Daar hij een geleerd man was, en door vertrouwelijken omgang met Columbus diens gedachten kende, was hij de rechte man, om zijn plannen op de duidelijkste wijze voor te dragen. De koningin had tot nog toe geen aandacht aan de zaak gewijd, want ofschoon de koning en de vergadering van geleerden ermee in kennis waren gesteld, tot haar had men zich nog nooit rechtstreeks gewend.

De lezer zal zich herinneren, dat Ferdinand alleen koning van Arragon was. Isabella was koningin van Castili?, en had een eigen inkomen, leger en hof. Dadelijk besloot zij Columbus te beschermen. Zij liet hem halen, opdat hij zich onmiddellijk naar Sant? F? begeven kon. Alzoo geroepen, om een bevel van de koningin uit te voeren, zond zij hem een voldoende som geld tot aankoop van een muilezel en een passend gewaad, om aan 't hof te verschijnen en ter bestrijding van de reiskosten.

Toen de prior met deze aangename tijdingen te La Rabida terugkwam, verheugde men zich daar zeer en nieuwe hoop straalde in de levensmoede ziel van Columbus. Er werd een mooie muilezel gekocht, de reiziger trok een net pak aan, en draafde weldra, als verjongd en door de hoop vroolijk gestemd, over de heuvels en door de schaduwrijke dalen van het schoone Andalusi?. Hij kwam nog tijdig genoeg te Granada aan, om te kunnen zien, dat men de vaandels der Mooren van de muren van het Alhambra afrukte, ten einde er de vlaggen van Ferdinand en Isabella voor in de plaats te stellen. Het was het schoonste oogenblik in de regeering van de beide b

FOSSIL MAMMALIA.

BY MR. OWEN.

It may be expected that the description of the osseous remains of extinct Mammalia, which rank amongst the most interesting results of Mr. Darwin's researches in South America, should be preceded by some account of the fossil mammiferous animals which have been previously discovered in that Continent. The results of such a retrospect are, however, necessarily comprised in a very brief statement; for the South American relics of extinct Mammalia, hitherto described, are limited, so far as I know, to three species of Mastodon, and the gigantic Megatherium.

This meagre condition of the historical part of the subject of South American fossils by no means arises from their actual scarcity. The writings of some of the old Spanish authors, for instance, Torrubia, Garcillasso, and others, contain frequent allusions to the bones of giants, who in times of old dwelt in Peru. Legentil, also, in 1728, speaks as an eye-witness of these Peruvian remains; and his guides pointed out to him the traces of the thunder-bolts, by which the Anaks of the New World had been exterminated. Bones and teeth of the Mastodon are, according to Humboldt, so abundant in a locality near Santa F? de Bogota in Columbia, that to this day it bears the name of the "Field of Giants."

But independently of these indications, the abundance and variety of the osseous remains of extinct Mammalia in South America are amply attested by the materials for the following descriptions, collected by one individual, whose sphere of observation was limited to a comparatively small part of South America; and the future traveller may fairly hope for similar success, if he bring to the search the same zeal and tact which distinguish the gentleman to whom Oryctological Science is indebted for such novel and valuable accessions.

It is remarkable that all the fossils, collected by Mr. Darwin, belong to herbivorous species of mammalia, generally of large size. The greater part are referrible to the order which Cuvier has called Edentata, and belong to that subdivision of the order which is characterized by having perfect and sometimes complex molar teeth, and an external osseous and tesselated coat of mail. The Megatherium is the giant of this tribe; which, at the present day, is exclusively represented by South American species, the largest not exceeding the size of a Hog. The hiatus between this living species and the Megatherium, is filled up by a series of Armadillo-like animals, indicated more or less satisfactorily by Mr. Darwin's fossils, some of which species were as large as an Ox, others about the size of the American Tapir. The rest of the collection belongs, with the exception of some small Rodents, to the extensive and heterogeneous order Pachydermata; it includes the remains of a Mastodon, of a Horse, and of two large and singular aberrant forms, one of which connects the Pachydermatous with the Ruminant Order; the other, with which the descriptions in the following pages commence, manifests a close affinity to the Rodent Order.

The cranium, which is the subject of the present description, was found in the Sarandis, a small stream entering the Rio Negro, and about 120 miles to the N. W. of Monte Video: it had been originally embedded in a whitish argillaceous earth, and was discovered lying in the bed of the rivulet, after a sudden flood had washed down part of the bank.

The general form of the skull, as seen from above, is pyriform; but viewed sideways, and without the lower jaw, it is semi-ovate; it is depressed, elongate, of considerable breadth, including the span of the zygomatic arches, but becoming rather suddenly contracted anterior to them, the facial part thence growing narrower to near the muzzle, which again slightly expands.

The zygomatic arches are of remarkable size and strength; they commence immediately anterior to the sides of the occipital plane, increase in vertical extent as they pass outwards, forwards and downwards, and are suddenly contracted as they bend inwards to abut against the sides of the sockets of the two posterior molar teeth.

The cranial cavity is remarkably narrow at the space included by the zygomatic arches; being, as it were, excavated on each side to augment the space for the lodgment of the temporal muscles, so that its diameter at this part is less than that of the anterior extremity of the upper jaw. The upper surface of the cranium expands to form the post-orbital processes, and again contracts anterior to these.

The muscular ridges, or other characters, at the top of the skull, cannot be precisely determined, as a great proportion of the outer table of the bone is broken away, exposing a coarse and thick dipl?e. There seems, however, to have been a strong ridge separating the occipital from the coronal or upper surface of the cranium. The form of the remaining parts, which are modified in relation to the attachment of the muscles of the jaws, indicates that these were powerfully developed both for the offices of mastication and prehension. The general form of the skull, while it presents certain points of resemblance to that of the aquatic Pachydermata, and even of the Carnivora, has much that is peculiar to itself; but, in the facial part, it approaches the nearest to that of the Rodentia; and the dentition of the Toxodon, as exhibited in the upper jaw, corresponds with that which characterizes the Rodent Order.

The general form and nature of the teeth are indicated by the sockets; and the structure of the grinders is exhibited in a broken molar, the last in the series on the left side of the jaw of the present cranium , and by another perfect molar, the last but one on the right side of the upper jaw, which, though not belonging to the same individual as the skull here described, undoubtedly appertains to the same species. This latter tooth was found by itself, embedded in the banks of the Rio Tercero, or Carcarana, near the Parana, at the distance of a hundred and eighty miles from the locality where the head was discovered. Fragments of a molar tooth of a Toxodon, apparently the seventh of the left side, upper jaw, were also found at Bajada de St^a F?, in the province of Entre Rios, distant forty miles from the mouth of the Rio Tercero.

Of the incisors, the two small ones are situated in the middle of the front of the upper jaw, close to the suture between the intermaxillaries, and the two large ones in immediate contiguity with the small incisors, which they greatly exceed in size. The sockets of the two large incisors extend backwards, in an arched form, preserving a uniform diameter, as far as the commencement of the alveoli of the molar teeth: the curve which they describe is the segment of a circle; the position, form, and extent of the sockets of these incisors are the same as in those of the corresponding teeth of the Rodentia.

The matrix, or secreting pulp of the large incisors, was lodged, as in the Rodentia, in close proximity with the sockets of the anterior molars; and we are enabled to infer, from the form of the incisive sockets, notwithstanding the absence of the teeth themselves, that the pulp was persistent, and that the growth of these incisors, like those of the Rodentia, continued throughout life.

In the Toxodon the position of the incisors, in the same transverse line, might lead to the inference, that they were opposed by a corresponding number in the lower jaw; but the numerous examples of inequality, in the number of incisors, in the upper and lower jaws of existing mammalia, forbid any conclusion on this point. The sockets of the small mesial incisors of the Toxodon gradually diminish in size, as they penetrate the intermaxillary bones, and we may, therefore, infer that the pulp was gradually absorbed in the progress of their development; and that, like ordinary incisors, their growth was of limited duration, and their lodgment in the jaw effected by a single conical fang.

I may observe, that the formation of a fang is the necessary consequence of the gradual absorption of the matrix or pulp of a tooth; for the pulp continues, as it diminishes in size, to deposit ivory upon the inner surface of the cavity of the tooth from which it is receding, and the tooth or fang thus likewise progressively diminishes in size. The formation of the socket proceeds uninterruptedly, and the bone encroaching upon the space left by the tooth, closely surrounds the wasting fang, and affords it a firm support; and thus an inference may be drawn from the form of the socket alone, as to whether the tooth it contained had or had not one or more conical fangs, and consequently whether its growth was temporary or uninterrupted.

Applying this reasoning to the molar teeth of the Toxodon, we infer that their growth, like those of most of the Phytiphagous Rodents, of the Megatherium and Armadillo, was perpetual, because their sockets are continued of uniform size from the open to the closed extremity; and the molar tooth which is preserved proves the accuracy of the deduction, inasmuch as its base is excavated by a large conical cavity for the lodgment of the pulp, the continued activity of which was the compensation here designed to meet the effects of attrition on the opposite or grinding surface of the tooth.

The molar tooth discovered by Mr. Darwin in the banks of the Tercero, not only belonged to the same species as the skull under consideration, but to an individual of the same size; it fits exactly into the socket next to the posterior one of the right side. The figures subjoined of this molar tooth almost preclude the necessity of a description. The transverse section of the tooth gives an irregular, unequal sided, prism; the two broadest sides of which converge to the anterior angle, which is obtusely rounded. The outer surface of the tooth is slightly concave in the transverse direction, but undulating, from the presence of two slight convex risings which traverse the tooth lengthwise. The inner surface presents at its anterior part a slightly concave surface, and posteriorly two prominent longitudinal convex ridges, separated by a groove which is flat at the bottom, and from the anterior angle of which the reflected fold of enamel penetrates the substance of the tooth, advancing obliquely forwards, rather more than half-way across the body of the tooth. A longitudinal ridge of bone projects from the internal side of the socket, and fits into the groove above mentioned, and as a corresponding ridge exists in all the sockets of the grinders, save the two anterior small ones, we may infer that the five posterior grinders on each side, had a similar structure to the tooth above described. The external layer of enamel is uniformly about half a line in thickness; it is interrupted for the extent of nearly three lines at the anterior angle, and for more than double that extent at the posterior part of the tooth, which is consequently worn down much below the level of the rest of the grinding surface. Where the ivory is thus unprotected by the enamel, it has a coat of caementum, which also fills up the small interval at the origin of the reflected fold of enamel. On the grinding surface of the entire tooth, and on the fractured ends of the mutilated molars, the component fibres, or tubules, of the ivory, are readily perceptible by the naked eye, diverging from the line which indicates the last remains of the cavity of the pulp of the tooth, as it was progressively obliterated during growth.

Although the complication of the grinding surface by the inflection of simple or straight folds of enamel is peculiarly characteristic of the Rodent type, we must regard the number of molar teeth, and their diminution of size as they advance towards the anterior part of the jaw, in the Toxodon, as indicative of a deviation from that order, and an approach to the Pachyderms. The common number of grinders in the upper jaw of Rodent animals is eight, four on each side. In some genera, as Lemmus, Mus, Cricetus, there are only three on each side, and in Hydromys and Aulacodus, only two on each side. In Lepus, however, we find six on each side of the upper, and five on each side of the lower jaw. The Toxodon, like the Tapir and Hippopotamus, has seven on each side of the upper jaw: the first in each of these species being the smallest. It is worthy of notice, however, that the Capybara which adheres to the Rodent type in the number of its molars, presents in the vastly increased size, and additional number of component laminae of the posterior grinders, an approximation to the pachydermatous character just adduced, and the bony palate at the same time presents an expansion between these molars, offering a resemblance to the Toxodon which I have not found in any other Rodent besides the Capybara.

The most important deviation from the Rodent structure presented by the teeth, occurs in the direction of the reflected fold of enamel, and such a deviation might have been inferred, even in the absence of the teeth, from the structure of the articular surface, or glenoid cavity for the reception of the condyle of the lower jaw. As the ridge of enamel runs, as above described, in a direction approaching that of the longitudinal axis of the skull, it is obvious that the grinding motions of the lower jaw should be in a proportionate degree in the transverse direction. The glenoid cavity, therefore, instead of being a longitudinal groove, and open behind, as in the true Rodents, is extended transversely, and is defended behind by a broad descending bony process preventing the retraction of the jaw, and showing marks of the forcible pressure to which it was subject.

It is worthy of observation that, in the Wombat,--which exhibits the Rodent type of dentition, and, like the Toxodon, has remarkably curved molars, but in an opposite direction,--the condyle of the lower jaw is also extended transversely, and adapted to an articular surface, which admits of lateral motion in the trituration of the food. In the outward span of the zygomatic arches, in which Toxodon deviates from the Rodentia, we may trace a relation of subordinacy to the above structure of the grinding teeth and joint of the lower jaw: the widening of the arches giving to the masseter muscles greater power of drawing the jaw from side to side. The depth of the zygoma bespeaks the magnitude of these masticatory muscles, and the included space shews that the temporal muscles were also developed to a degree, which indicates the force with which the great incisors at the extremity of the jaws, were used; probably, like the canines of the Hippopotamus, to divide or tear up by the roots the aquatic plants, growing on the banks of the streams, which the Toxodon may have frequented.

In the Rodentia, the zygoma, though sometimes as deep as in the Toxodon, is generally almost straight, and the space included between it and the cranium is consequently narrow. The zygoma also is placed more forwards in all true Rodents, than in the Toxodon; and, instead of abutting against the posterior alveoli, it terminates opposite the anterior ones. It thus affords such an attachment to the masseter, that this muscle extends obliquely backwards to its insertion in the lower jaw, at an angle which enables it to act with more advantage in drawing forwards the lower jaw,--a motion for which the joint is expressly adapted. In many Rodents, also, there is a distinct muscle, or portion of the masseter, which passes through the ant-orbital foramen, which is on that account of large size. In examining the cranium of Toxodon, with reference to this structure, it was found that the ant-orbital foramen was not larger than might have been expected to give transmission to nerves requisite for supplying with sensibility the large lips, and whiskers with which the expanded muzzle of this remarkable quadruped was probably furnished.

The orbit of Toxodon forms the anterior boundary of the zygomatic area; it is about as distinctly defined as in the Tapir or Dugong, having its osseous rim less complete than in the Hippopotamus, yet more developed than in the Capybara, Coypus, and many other Rodentia, in which the orbit is scarcely distinguishable in the cranium from the small space occupied by the origin of the temporal muscle.

The lower boundary of the orbit in Toxodon is formed by an excavation in the upper and anterior part of the zygoma; the upper boundary by a strong and rugged overarching process of the frontal bone, the posterior angle of which descends a little way, but leaves a space of three inches and a half between it and the opposite angle of the malar bone below , the circumference of the orbit being completed probably by ligament in the recent subject. The cavity thus circumscribed is remarkable for the preponderance of the vertical over the transverse or longitudinal diameter, and indicates great extent of motion of the eyeball in the vertical direction, such as may be supposed to be well adapted to the exigencies of an amphibious quadruped. The orbit of the Capybara, or Water-hog, makes a near approach to the form just described. In the elevation of the supra-orbital boundary, and its outward projection in the Toxodon, we perceive an approximation to the form of the orbit in the Hippopotamus, but the size of the orbit is relatively larger in the Toxodon, which in this respect manifests its affinity to the Rodentia.

In that part of the bony structure of the auditory apparatus, which is visible on the exterior of the cranium, the skull of the Toxodon presents a character in which it recedes from the Rodentia. In these, the tympanic portion of the temporal bone is remarkably developed, forming a large bulla ossea between the glenoid cavity and the occiput; and it always remains disunited to the other elements of the temporal bone. In the Toxodon the tympanic bone consists of a rough compressed vertical osseous plate, wedged in transversely between the occiput and the posterior part of the glenoid cavity. The internal extremity of this plate points inwards and forwards, representing the styloid process; behind this is seen the petrous bone, which forms a small angular protuberance at the basis cranii, and is less developed than in the Hippopotamus. Anterior to the petrous bone are the orifices of the Eustachian tube, and carotid canal; external to it is the great foramen lacerum, for the jugular vein and nervus vagus; and behind it is the anterior condyloid foramen. The foramen auditorium externum is only half an inch in diameter, and gives passage to a long and somewhat tortuous meatus, which passes inwards and slightly forwards and downwards; its direction being precisely the same as in the Hippopotamus; it was accompanied, probably, by as small an external auricle.

But the indications of the aquatic habits of the Toxodon, which are presented by the osseous parts relating to the senses of sight and hearing, are of minor import compared with those afforded by the bony boundary of the nostrils. This boundary circumscribes a large ovate aperture, the aspect of whose plane is upwards, and a little forwards, as in the Herbivorous Cetaceans, and especially the Manatee In one part of the bony structure of the nasal cavity the Toxodon deviates, however, in a marked degree from the Cetaceous structure; I allude to the frontal sinuses, which are exposed by the fracture of the upper part of the skull. The posterior orifice of the nasal cavity is relatively larger and wider than in the Herbivorous Cetaceans, and differs both in form and aspect in consequence of the greater extent of the bony palate. The Toxodon further differs from the Manatee and Dugong, in the firm nature of the connexion of the bones of the head; and it differs from the Hippopotamus in the strong attachment of the intermaxillary bones to the maxillaries.

There next remain to be described, as far as the shattered condition of the skull will permit, the relative position, extent, and connexions of the principal bones composing it.

The ex-occipital processes advance forwards for about an inch beyond the condyles, and then suddenly extend outwards at right angles to the former line, and terminate in the form of vertically compressed bony plates; the lower rugged margins of which represent or perform the office of the mastoid processes . The breadth of the entire occipital region of the skull appears to have been, allowing for the fractures, about one-third more than the height of the same part.

The cavity of the nose is extensive, and the remains of the ossa spongiosa superiora testify that the Toxodon enjoyed the sense of smell to a degree equal at least to that of the Hippopotamus.

Ter eere van koning Ferdinand gaf Columbus aan dit eiland den naam van Fernandina, maar later is het Exhuma genoemd. Columbus beproefde er omheen te varen. Naar het noordwesten zeilende, vond hij eene heel mooie haven, waarin een honderdtal schepen veilig voor anker kon liggen. Hij liep die haven in, en ging met een gezelschap aan land, om water te halen. Terwijl de matrozen de tonnen vulden, wandelde Columbus een klein eind verder, en ging op een groenen heuvel zitten, om het schoone gezicht te bewonderen, dat hem van alle kanten omgaf.

In zijn dagboek betuigt hij: "Nooit heb ik vroeger zulk een prachtig landschap gezien." Het was zoo frisch en groen, als Andalusi? er in Mei uitziet. De boomen, de vruchten, het gras en de bloemen waren heel anders dan in Spanje. De bewoners waren heel vriendelijk. Zij wezen den Spanjaarden de beste waterbronnen aan, hielpen hen de tonnen vullen en ze naar de booten rollen.

Ofschoon Columbus' verbeelding veel voedsel kreeg, viel het hem toch bitter tegen, dat er niet meer goud was. Omdat het duidelijk was, dat hij op dit eiland niets van dit kostbaar metaal kon krijgen, zeilde hij den 19en naar een ander eiland, dat de inboorlingen Saometa noemden. Hij had uit de teekens der wilden afgeleid, dat daar goudmijnen waren, dat het de residentie van het voornaamste opperhoofd of van den koning van al de omliggende eilanden was, en dat die een met juweelen en goud omzoomd gewaad droeg.

Toen zij op het eiland aangekomen waren, vonden zij er noch monarch noch goudmijn. De bewoners waren talrijk, het eiland was verrukkelijk en het afhankelijke hoofd droeg heel gewone versierselen. Wat Columbus erg verwonderde was, dat ieder eiland telkens mooier scheen dan dat, 't welk men van te voren had bezocht, en werkelijk bestond er een groot verschil in de natuurtooneelen. De boomen en bloeiende struikgewassen, welke dit eiland bedekten, waren zeldzaam mooi. Op het eiland vond men hoogten, die vrij aanzienlijk waren. De lucht kwam hem in 't bijzonder zeer welriekend voor, en het fijne zand op het strand werd door golven bespoeld, die bijna zoo doorzichtig waren als kristal. Midden op het eiland vond hij verscheidene schoone meren vol helder water. Aan dit eiland gaf hij den naam van Isabella, ter eere van de koningin, wier aandenken hij met zooveel trouwe toewijding liefhad. Van dit eiland, dat nu Exumeta heet schreef hij:

"De groote meren, welke men hier aantreft, en de boschjes, waardoor ze omringd worden, zijn wonderschoon. En evenals op andere eilanden is hier alles groen. De vogels zingen hier zoo, dat men er altijd naar zou willen luisteren. De vluchten papegaaien zijn hier zoo groot, dat de zon er door verduisterd wordt en de andere vogels, zoo groot als klein, zijn zoo veelsoortig en verschillen zoozeer van de onze, dat men zich er over verbaast. Bovendien ziet men hier duizenderlei soorten van boomen, die elk hun eigenaardige vruchten hebben, waarvan de smaak heel vreemd is, zoodat het mij erg spijt, dat ik ze niet ken; want ik weet zeker, dat ze veel waard zijn. Ik zal er als proef eenige mee naar huis nemen, en ook eenige grassoorten."

"Toen ik hier kwam, kreeg ik van de boomen en bloemen van het land zulk een aangenamen reuk in den neus, dat er in de wereld niets lekkerders wezen kan. Ik geloof, dat hier vele grassen en boomen zijn, waarop men in Spanje zeer gesteld wezen zou, om er aftreksels, geneesmiddelen en specerijen van te maken; maar ik ken ze volstrekt niet, en dit spijt mij zeer."

Niet alleen de vogels, die van tak tot tak sprongen, droegen prachtige veeren, maar ook de visschen, waarvan die kristalheldere wateren wemelden, vertoonden al de schoone kleuren van den regenboog. Zij wedijverden met de vogels in kleurenpracht.

De dolfijnen vooral, die gemakkelijk te vangen waren, verrukten de beschouwers door de wondervolle kleurveranderingen, die zij te zien gaven. Het is eenigszins merkwaardig, dat er geen viervoetige dieren gevonden werden, uitgezonderd een paar zeer kleine. Er was er een, die veel op een hond leek, maar in 't geheel niet blafte. Er waren ook eenige konijnen en hagedissen, welke laatste de Spanjaarden met afkeer en vrees beschouwden, alsof het vergiftige kruipende di is obviously incompatible with a foot incased in a hoof:--but where the teeth are adapted for triturating vegetable substances the case is different. If animals so characterized are of small size and seek their food in trees, or if they burrow for roots or for shelter, the vegetable type of dentition must co-exist with unguiculate extremities, as in the Edentata and Rodentia generally: but the largest genus of the Rodent Order, whose affinity to the Pachydermata is manifested in its heavy shapeless trunk, thinly scattered bristly hair, and many other particulars, has each of its toes inclosed in a miniature hoof.

The affinity above alluded to, is too obvious to have escaped popular notice, and the Capybara, from its aquatic habits, has obtained the name of Water-hog. It is highly interesting to find that the continent to which this existing aberrant form of Rodent is peculiar, should be found to contain the remains of an extinct genus, characterized by a dentition which closely resembles the Rodent type, but manifesting it on a gigantic scale, and tending to complete the chain of affinities which links the Pachydermatous with the Rodent and Cetaceous Orders.

ADMEASUREMENTS OF THE CRANIUM OF TOXODON. feet inches lines Extreme length 2 4 Extreme breadth 1 4 Extreme height, 10 Length of zygomatic process 1 1 6 Depth or vertical extent of do. 6 Transverse extent of zygomatic fossa 6 Transverse diameter of cranium between the zygomatic arches 5 Transverse diameter of occipital plane of the cranium 1 From the outside of one condyle to that of the opposite condyle 8 6 Length of the bony palate 1 6 Extreme breadth of ditto 6 Breadth of palate at the intermaxillary suture 2 6 Breadth of palate behind the molar alveoli 3 Longitudinal extent of the molar alveoli 9 6 Longitudinal extent of the diastema 5 6 Transverse diameter of posterior nasal aperture 3 9 Transverse diameter of occipital foramen 3 Transverse diameter of glenoid cavity 4 6 Antero-posterior do. of ditto 1

DESCRIPTION OF FRAGMENTS OF A LOWER JAW AND TEETH OF A TOXODON.

Found at Bahia Blanca, in latitude 39? on the East coast of South America.

In looking over some fragments of jaws and teeth, forming part of Mr. Darwin's collection of South American mammiferous remains, and which had been set aside with mutilated specimens referrible to species belonging to the family of Edentata, my attention was caught by the appearance of roots of teeth projecting, in a different direction from the grinders, from the fractured anterior extremity of a lower jaw, and I was induced to examine minutely the structure of the teeth in this specimen, and to search the collection for corresponding fragments. The result was the discovery of portions of the two rami, and the commencement of the symphysis of a lower jaw, containing anteriorly the roots of six incisors, and at least six molars on each side; but as the rami had been fractured through the middle of the sixth alveolus, the number of grinders may have corresponded with those in the upper jaw of the Toxodon.

The pulps of the six incisors in this lower jaw are arranged in a pretty regular semicircle, whose convexity is downwards; the teeth themselves are directed forwards, and curved upwards, like the inferior incisors of the Rodentia. The form and degree of the curvature are shown in the almost perfect incisor which corresponds with the left inferior incisor of the lower jaw, and was found in the same stratum, but belonged to another individual.

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