of the Palearctic Fauna. The other, and more striking exception, is a species of the North American genus Plethodon, stated to have been found in Siam by the late M. Mouhot.* In the latter case, we cannot help thinking that there may have been some error. Either the two specimens stated to have been found in Mr. Mouhot's collection, which are the sole authority for the Siamese locality, may have been accidentally introduced from elsewhere we know that such accidents do occur even in the best-ordered establishments -or we think it possible that the animal may have been brought over to Siam in an American vessel. Certainly, further evidence as to the occurrence of Tailed Batrachians in Siam is very desirable. We are not yet quite convinced of the fact!

Of the worm-like Cæcilians or Burrowing Batrachians, as Dr. Günther terms them, three species occur in British India. It is not long ago that the late Johannes Müller's discovery of the metamorphosis of these singular creatures caused their degradation into the class of Batrachia. Dr. Günther's discoveries as to the structure of the uro-genital apparatus in Epicrium glutinosum (see p. 442), will probably cause their elevation to the head of the Batrachians, and certainly tends to diminish the ordinarily insisted on distinction between the Batrachia and the true Reptilia. If Dr. Günther's views are correct, the middle portion of the cloaca in this species is developed into a copulatory organ, provided with special muscles for its retraction, and imitates a similar structure known to exist in certain Saurians.

We now take our leave of Dr. Günther's work, which on several accounts we take to be one of the most important contributions to Zoological science that have lately appeared in this country. It is important, not only for its own sake, as a highly elaborate account of the present state of our knowledge of a part of the Fauna of a rich tropical region, of which we had previously no connected history, but also for the results which will slowly but surely follow it. It will certainly bring a number of new workers, who will now have something to start upon, into a very neglected branch of Natural History. It will also tend to wipe away the national reproach that might have been deservedly cast upon us, of not caring for the

*Cf. Gray, P.Z.S. 1859, p. 230.

interests of science as regards Indian matters.

If our Government is utterly indifferent to such undertakings-and we believe they refused even to subscribe for a single copy of the present work -we have Associations amongst ourselves who will supply its shortcomings, and provide means for bringing the labours of our Naturalists before the world. In the name of Science we thank Dr. Günther for his work, and the Ray Society for publishing it.

XXVII.-THE STRUCTURE OF MACRAUCHENIA.

(1.) DESCRIPCION DE LA MACRAUCHENIA PATACHONICA. ANALES DE MUSEO PÚBLICO DE BUENOS AYRES. Por German Burmeister, Med. Dr., Phil. Dr., Director del Museo Público de Buenos Aires. Entrega prim., Buenos Aires. 1864.

(2.) BESCHREIBUNG DER MACRAUCHENIA PATACHONICA, Owen. (Opisthorhinus Falconeri, Brav.) Nach A. Bravard's Zeichnungen und den im Museo zu Buenos Aires vorhandenen Resten entworfen von Dr. Hermann Burmeister. Abhand. d. naturf. Ges. zu Halle. Bd. IX., p. 75. Halle. 1864.

In our last number* we spoke of Dr. Burmeister's forthcoming account of the Osteology of Macrauchenia, from the fossil remains in the Museum of Buenos Ayres,† of which he is now Director. Dr. Burmeister's essay on this subject has since appeared in two publications, as will be seen by the title of them above given, and fully equals in interest the expectations we had formed of it.

The original discovery of the singular form of extinct Mammals known as Macrauchenia is due to Mr. Darwin, who, during the voyage of the Beagle, in 1842, found the first known specimens of the remains of this animal at Port St. Julian, on the coast of Patagonia. Upon these remains, which consisted mainly of vertebræ and bones of the anterior extremities, Professor Owen, in the

Antea, p. 300.

It appears, however, that the skull of Macrauchenia, certainly the most valuable part of the skeleton, is not in the National Museum, but belongs to the late M. Bravard's private collection, and is now for sale. Surely this is worth the attention of the authorities of the British Muscum.

Zoology of the Voyage of the Beagle, established the species Macrauchenia patachonica. Professor Owen considered that this remarkable quadruped, though "referable to the Order Pachydermata," judging from the peculiar formation of the cervical vertebræ, must have had "affinities to the Ruminantia, and especially to the Camelidæ."

Further remains of the Macrauchenia patachonica were discovered by the Vicomte F. de Castelnau during his journey through South America, and described by Gervais, in the "Zoology" of that traveller's "Voyage." Professor Gervais does not recognize any affinity between Macrauchenia and the Camelidæ, but insists on its close alliance to Rhinoceros and Tapirus, the structure of its foot being nearly the same as in these two latter genera.

In 1859, Mr. D. Forbes, F.R.S., obtained portions of a skeleton from the copper mine of Santa Rosa, in Bolivia, upon which Professor Huxley has founded a second species of Macrauchenia— M. boliviensis. Here again, only two very imperfect and mutilated portions of the skull were present, so that the great question as to the true position of the genus could not be definitely set at rest. It will be evident, therefore, that the discovery by Bravard of a perfect cranium of this animal, together with other portions of the skeleton, near Buenos Ayres, was an event of no slight interest, and well worthy of the attention which Professor Burmeister has devoted to it.

M. Bravard made his discovery as long ago as 1856, and, not recognizing that the cranium was that of Macrauchenia, commenced a description of it, in a new work intended to illustrate the fossil Fauna of La Plata, under the name Opisthorhinus falconeri. Bravard unhappily perished in the fatal earthquake of Mendoza, leaving only three plates of his proposed work completed, which have been used by Professor Burmeister for the Spanish edition of his paper in the "Anales."

We shall not follow Prof. Burmeister into his description of the cranium, the dentition, and other particulars of the structure of Macrauchenia, but shall content ourselves by giving a short analysis of the results arrived at at the close of his paper as to the systematic position of this remarkable Mammal.

• Zool. Voy. Beagle, I., p. 35.

† Proc. Geol. Soc. Lond. XVII., p. 70.

"If," says Professor Burmeister, "we divide the Ungulate "animals according to the structure of their feet into Artiodactyles "and Perissodactyles, there can be no doubt that the Ruminants "must form one end of the series, and the Elephants (Proboscidea) "the other. In this way we get a natural series, beginning with “the Ruminants, and passing through Anoplotherium to the Swine "(Suina) and so to Hippopotamus, which concludes the series of "Artiodactyles. The transition to the Perissodactyles is, perhaps, "effected by Toxodon, of which the structure of the feet is not yet "accurately known, but which seems to unite certain characters of "Rhinoceros with those of Hippopotamus. To Toxodon succeed "Rhinoceros, Hyrax and Palæotherium-genera, of which the dentition "is reducible to one common plan. Next, however unnatural it may at first appear, we must place the Solidungula—the fossil genus Hipparion, forming the transition between Equus and Palæotherium, and, on the other side, comes in Macrauchenia, "perhaps along with Nesodon. To Macrauchenia succeeds Tapirus; "and the series is closed by Elephas."

It will be observed, therefore, that Prof. Burmeister considers that the true position of Macrauchenia is now definitely settled to be between Equus and Tapirus, and that the resemblance to the Camelidæ, indicated by its cervical vertebræ, is entirely analogical, and unsupported by any other characters. He defines the genus as follows:

:

Macrauchenia, genus Ungulatorum imparidigitorum, inter genera Equus et Tapirus ponendum-Dentes 46, serie continua-Primores utrinque sex- Laniarii parvi, conici, inferiores majores. Molares supra utrinque octo; anteriores compressi, posteriores quadrati: infra septem bilunati-Nasus elongatus, proboscideus. Cranium figura cranio Caballi proximum-Palmæ et plantæ tridactylæ, digitis æqualibus; astragalus superficie unica articulatoria suborbiculari cum osse scaphoideo conjunctus; digitis externis et internis accessoriis obsoletis, sed conspicuis."

• The dentition is formularized as follows (Abh. N. G. z. Halle, p. 85)—
8-8

I.

6

1., C. M. 7-7

The great peculiarity, besides the large number of the teeth and the eight superior molars, consists in the series being almost continuous, only one small diastema occurring, between the canines and incisors in the upper jaw. In this respect Macrauchenia approaches Anoplotherium.

N.H.R.-1865.

Z

We conclude this notice with the very significant moral, which Prof. Huxley has attached to his account of the second smaller species of Macrauchenia, and which acquires additional strength now that the true position of the genus is definitely ascertained. The "genus Macrauchenia," Prof. Huxley remarks, "alone affords a "sufficient refutation of the doctrine, that an extinct animal can be "safely and certainly restored if we know a single important bone or tooth. If up to this time the cervical vertebræ of Macrauchenia "only had been known, paleontologists would have been justified "by all the canons of comparative anatomy, in concluding that the "rest of its organization was Camelidan. With our present knowledge (leaving Macrauchenia aside), a cervical vertebra with elongated centrum, flattened articular ends, an internal vertebral canal, and "imperforate transverse processes, as definitely characterizes one of "the Camel tribe as the marsupial bones do a Marsupial,-and indeed "better; for we know of recent non-marsupial animals with marsu"pial bones. Had, therefore, a block containing an entire skeleton "of Macrauchenia, but showing only those portions of one of the "cervical vertebræ, been placed before an anatomist, he would have "been as fully justified in predicting cannon-bones, bi-trochanterian "femora, and astragali with two, subequal, scaphocuboidal facets, as Cuvier was in reasoning from the inflected angle of the jaw to the marsupial bones of his famous Opossum. But, for all that, our "hypothetical anatomist would have been wrong; and, instead of "finding what he sought, he would have learned a lesson of caution, "of great service to his future progress."