A RE P o R T on some Fossil Boncs a . the iWcgalonyx, f r m Virginia ; with a notice o$ such parts of the skeleton of this

animal as have been hitherto discot?ered, a~id remarks on, thc afiiiities which they indictrte, By WI L L I A M C o o P E R.

Read Jnnunry, 1833.

THESE bones were presented to the Lyceum about a year ago, by hIr. G. S. Bibby, of this city. Two of them are ev+ dently ungueal phalanges : and the third, which fits well upon the upper extremity of the larger of them, and probably belongs to it, is a middle phalanx. By comparing them with the casts of those originally discovered in Virginia, their place in the skeleton may be determined with much exactness. The larger corresponds to that which Cuvier, having the metacarpal bones and first phalanges, and numerous objects of coniparison among the kindred animals, pronounces the last phalanx of the left middle finger, or fore toe. A slight difference, however, in the convexity of the two sides, which in ours is greater on the left, while in the Jefferson bone it is greater on the right, shows that it is from the opposite side of the animal. It is therefore the last phalanx of the right middle finger, to which also the middle phalangial bone must have belonged.

The other ungueal phalanx conesponds to that which Cuvier judges to have been the last of the annular or third finger of the left side; except being also, for the same reason, evidently from the opposite side. It is, however, in better preservation than the analogous one now in Philadelphia, as it retains all of one side of the great bony sheath, of which Cuvier, from an examination of the casts, supposed the iMegaZonyx to have merely the vestiges9 but, as Dr. Harlan has already remark-

-

* Osiem. Foss. V. pt. 1. p. 190.

Fossil !Bones of the Megalonyx. 167

ed, all the ungueal phalanges were furnished with very large ones, though they are generally found broken off. I n these remarkable sheaths the foot resembles that of the Megiitherium, which had them so large as to encase the phalanx for more than half its length. In the Megalonyx the sheath wa9 not complete, as it appears to have been open above, along the back of the bone ; a circumstance which is also observed in the Myrrnccophaga jtlbntn. T h e use of these sheaths mas to strengthen and support the great CIQWS, the base of which they firmly embraced.

The extreme rarity of these remains, and the unusual kind of animal which they bespeak, confer an interest upon every additional discovery. The bones now presented to the Lyceum had been preserved, for several years, as curiosities, at the mansion of the late President Monroe, and were thought to be b b petrified lobster’s claws.” Their origin is no longer known, but to judge from their colour and appearance, they have been preserved from decay in the same manner as those first described by Mr. Jefferson, and very probably belonged to the same skeleton; of which many bones were carried off and dispersed before the discovery became known to him. It is a circum- stance in favour of this conjecture, tbat they now prove to have belonged to the corresponding limb of the opposite side. ‘Not- withstanding an appearance of antiquity, they are hard and sound, and their composition is apparently unchanged.

T h e following is a general view of the parts belonging to the skeleton of the Megalonyx that have been hitherto disco- vered, and of the affinities which they indicate with the other animals of the order Edentatn., --- - ~--

It will be observed that I speak of these bones as all belonging to one epecies of animal. Dr. Harlan and Mr. RaGnesque, on the contrary, are of opinion that those found in Kentucky belonged to a different epe- cies corn the Megalonyx of Jefferson.

1. Upon the different proportione, and the longitudinal groovee or flutings observable in the teeth from Kentucky.

2. The different form and proportions, and greater etrengtb of the u- p e a l phdangee, and their baGDg a notch h e a d of a vascular foramen.

Dr. H. founds his opinion,

VOL. rLI. 22

168 Fossil Bones of the Megalonyz.

0. Of the Head. The only portions of the head yet known to have been dis-

covered in the United States are two or three teeth, presumed to be from the upper jaK, and a very much mutilated right lower jaw and teeth. A tooth was found in a cave in Virginia, and another in a cave in Kentucky ; which, with Big-Bone Cave, in Tennessee, are the only known localities of these remains in this country.

This jaw is too imperfect to show whether, like all others of thi3 family, the animal was deprived of incisor teeth. As well as can be judged, it resembles that of the Ai, or Three- toed Sloth, more than any other ; having, like it, a sort of doubt- ful canine tooth, but. compressed laterally, instead of trans-

This was found at Big-Bone Lick.

S. The great difference between a supposed metacarpal bone from Kentucky and those found in Virginia.

These distinctions do not seem to me such as can be e d d y depended on. Iu the first place, it appears Crom Cuvier’e figure of the only tooth known of the Virginian Megalonyx, that it possessed the same charac- teristic fluting, though in a slighter degree ; and secondly, all the five teeth from Big Bone Lick are different from each other in this respect, four being very deeply and variously grooved, and the fifth, though im- perfect, having very evidently been but slightly 60 ; like, in this, to the tooth from Virginia. In proportions, those i n the jaw from Kenmcky are totally unlike each other.

The differences obsemed in the phalanges I would account for, p a d y by supposing that those from Kentucky have belonged to the hind foot. Those from Virginia are, no doubt, from the fore feet. Along with those from Kentucky were found an 0s calcis, tibia, and other portions of the hinder extremity. Their having a notch in place afa foramen, may be fairly attributed to imperfect ossification, as it zippears, from the condition of the other bones, that the individual w m not adult.

The last point ofdiaerence 21 indeed important, and would be decisive of h e difference of species, if the bone hitherto called, even by myself, metacarpal, were well determined to be in fact such. The metacarph of&e Virginian Megalonyx are sufliciently known to prove &at it can- not be my of them. But is it not metatarsal? I see no difliculty in considering it such ; and in size and strength it corresponds with the large ungueal phalange8 From Kentucky, which, as I bave obgerved, there is reamn to think belonged to the hind foot.

FOStil BM of' th MegaLany~. 169

versely to the jaw, and three molars, Werent from my before known, and of which an idea may be best formed by referring to the figure given by Dr. Harlan in the American Journal of Geology. The structure of these teeth is the ~ a m e in all; consisting of a bony substance, encased in enamel, which merely forms a border round the crown. This jaw-bone is now preserved in the collection of the Lyceum.

Q Q. Oj'the Trunk. But few portions of the trunk have been found : they include

seven vertebrz, three entire ribs, with fragments of others, and the chief portion of an 0s ilium. Part of these were discovered in the White Cave, in Kentucky, aDd the rest in Big-Bone Cave, in Tennessee. For a knowledge of the latter locality we are indebted to Dr. G. Troost, who has recently published an account of it in the Transactions of the Geological Society of Pennsylvania. The remains from White Cave are describe'd and figured by Dr. Harlan, in the Journal of the Academy of Natural Sciences..

0 0 0. Anterior ExtTemity.

This is better known than any other part of the skeleton.- The scapula is among those found in the White Cave, and the clavicle at Big-Bone Lick. A humerus, young and imperfect, accompanied the scapula; but one more complete has been dug up at Big-Bone Lick. The bones of the fore-arm were amongst those originally discovered in Virginia, and a young radius was found in White Cave.+

At a recent meeting of the Lyceam, Dr. Harlan informed the Society+ that the banes which he had described as from White Cave, he bad s k e mrtained to have been found in Big-Bone Cave, TeDneeoe!e. This would reduce the known localities to three', unless tve include the Mummy Cave, mentioned by Mr. Rahesque.

f Or, according to Mr. R d n e q u e , in the Mummy Cave near it. Atl. Joar. ooI. I. p. 28.

170 Fossil Bones of the Megalonyx.

The carpus is yet unknown. Of the metacarpus there are three bones from Virginia, supposed to be of the fore, middle, and third toes of the left fore-foot. The same locality furnished the three bones of the middle toe of the same foot; with the middle and last phalanges of the third, and the last of the second, with a hdimentary bone representing the fourth. The three phalanges just received hy the Lyceum belong, as we have seen, to the right fore-foot.

Of the animals belonging to the same order, whose osteo- logy is best known, the scapula of the Jlegalonyx most resem- ,,

bles, as Dr. Har lan has pointed out, that of the Grcat Ant- eate?., which is itself very different from most of its kindred in the form of this bone. That of 'the Megalonyx wants the ridge, so like a second spine, which distinguishes the scapula of this Ant-eater. It has also the same foramen, in place of a notch, near the anlerior border, which is observed in several others besides these, especially the Sloth and hlegatherium-

I n having perfect clavicles the Megalonyx resembled the Megatherium, one species of Sloth, and one hlyrmecophaga ; but differs from others of the same families, the Ai having merely imperfect clavicles; while the two species of Ma&, the Orycteropus, and two Myrrnecophaga, have none at all.

The humerus of the Megalonyx is materially dissimilar from the same bone in both the Sloths and the Megatherium, with which genera it has been usual to confound this animal. It has neither the excessive length and slenderness of that of the for- mer, nor the short and massive form peculiar to this bone in the latter, which it approaches in the great breadthand flatness of the lower portion. It is much more like the humerus of the Ant-eaters, and especially the Orycteropus, an animal from which, in other particulars, it differs more perhaps than from any other of this order. It is, as in this and other Edentata, but excepting the Sloth and Megatherium, perforated below on the side next the body.

I n the bones of the fore-arm the Megalonyx partakes of the characters of the Sloths and Ant-eaters : but shorter and stouter

Fossil BW of the Megabnyt. 17 1

than the former, and with proportions more like the latter of these animals.

The osteology of the fore-foot preaenfs a combination. of characters drawn from the sloths, ant-eaters, and some speciea of Armadillo, particularly the twelve-banded and the giant .4r- madillo ; though Cuvier considers it to have .resembled one of thesenlast more than any other. The ungued.phalaogee re- semble those of the S l o h , but with a bony sheath, likelaat of the Ant-eaters, open above on the back of the phalanx- In the inequality of the fingers, and particularly the great d a t i v e size of the medius, it is like the Armadilloes and Ant-eaters. Similar affioities to all these animals may be traced in the other bones composing the metacarpus and phalanges.

0 $ $0. Posterior Eztremity.

Of this very little is known. Dr. Harlan describes the lower extremity of a femur, which, with a young tibia and a calcaneum, were found in the White Cave. Themis I i k e d e a tibia of an adult individual, found at Bigdone Lick. If in). conjecture is right, we have also a metatarsal from the game place; and two phalanges of the hind foot, from White Cave. But what is most extraordinary, and a faot of high interest to the geologist especially, one of the claws, in excellent pteser- vation, was procured from the same cave.

From these portions it is, however, easy to detect no lese N- ference between the hinder, than we have ,found to exist be- tween the anterior extremities of the Sloth and the Megalonyx. The tibia, in its average dimenaions, is. not much more than twice as long as broad ; and though it does notmuch resemble any of the co-ordinate animals in this part, it comes neareat to the Megatherium. The union of the tibia and fibulainto one, which takes place in the Megatherium and the Armadilloee,& not found in the Megalonyx; or if they were slightly joined at

the upper extremities, the anchyloais was not so complete ae

' Journal Acad. Nat. Sc. Pbila. vol. VI.

172 Fossil Bones o$ the Megalonyx.

to prevent the two bones from being essentially distinct. In the Megatherium found in Georgia they form but one, without a m e of suture or any other indication of having been ever separated at either extremity.

So little is known with certainty of the hind-foot, that we cannot aafely hazard any remarks upon it. On the whole, it appears probable to me, that in the posterior extremity the Megalonyx most resembled the Megatherium ; except, perhaps, in the foot. In the latter this member was furnished with only m e apparent toe, armed with an enormous claw. The rudi- ments of others were concealed beneath the skin.

In short, we find united in the Megalonyx, a head like that of the SZoth, (ai) a scapula like the Great Ant-eater's, the hume- rus of the Orycteropzls, the fore-arm of the Ant-eaters, the feet of an ArmadilEo, with a resemblance also to those of the Mega- therium; while, in the hinder extremities, it presented a- struc- ture peculiar to itself. In size it far exceeded any species of the same order now existing. The humerus found at Big- Bone Lick, when compared with the largest Bison's, which are commoneat that spot, indicated a much larger animal. It must have been equal to the largest ox, though greatly inferior to the ponderous bulk of the Megatheriam.

It is evident, therefore, from this comparison, that tbe Mega- lonyx formed one of a tribe of animals, in which are comprised several distinct genera, with all of which it had many important characteristics in common, but differed horn each and all in so many particulars, as to deserve, on every account, to consti- tute an independent genus. This was foreseen by Jefferson when he proposed for it the name it still beam: and thougb some naturalists have been disposed to consider it a species of' B r d y j ~ , and others have declared it the same with the Mega- ihe&m,. yet it can no longer, in the present state of zoology, be included even in the same genus, without giving a0 mphi-

Pander et d'Altoa. Das Riese Faaltbier.

Fossil Bones +he Megalonyx. 173

losophical latitude to the term. Even Cuvier, however, in the latest edition of his great work,. speaks of these two animals as belonging to one genus. But, though they seem to have had a somewhat similar form of the bead, and lthelsatpe number of, teeth, yet the great differences which are obviobs. in) &em, at the first view, in their kind, their form, and) their .struotuh,t render wch an union forced and incongruous.

The Megatheriurn and the Megalonyx have been found in both North and South America. The former having b e e a h t discovered in the southern continent, and the latter $ the northern, have become in a manner’ identified with these re- spective localities, as peculiar to each ofl them; but they appear, from what is now knowq,,to have ithabitad. a regiop extending for many degrees on each side of the equator.

Omem. Foes. v. p. 67.

t See Ann. Lyc. vol. I. p. 121.. pl. viii.