Aligns? 2 1, 1884] 



NA TURE 



39i 



again closes its scales and enters the water. He now 

 again erects the scales, the ants are set Moating, and are 

 then swallowed by the anteater. 



From a list of the Holothurians in the collection of the 

 Leyden Museum, drawn up by Prof. Dr. Hubert Ludwig 

 of Giessen, we find that the majority of the specimens in 

 the Museum were incorrectly named, which is somewhat 

 surprising; it seems also strange that of the species not 

 so very long since described by Prof. Selenka the speci- 

 mens are either sine patria or have the rather indefinite 

 habitat of" Indian Ocean." The collection contains fifty- 

 two species, two being new ; most of them were obtained 

 from the Oriental and Moluccan regions. 



In vol. v. Dr. Jentink continues his very useful re- 

 searches on the squirrels in the Museum. This time he 

 treats of the American, European, and Asiatic squirrels ; 

 he acknowledges that the profound and extensive studies 

 upon the American squirrels by Allen and Alston have 

 made this group one of the best known among the Mam- 

 mals : he enumerates ten species from America, forty 

 from Europe and Asia. All the former are represented 

 generally by numerous examples in the Museum, and of 

 the latter only six species are among the desiderata. 



The same volume contains <; Notes of new species of 

 the genus Megascolex, Templeton,"by Dr. R. Horst. Very 

 satisfactory evidence is given to show that Schmarda's 

 genus Perichaeta is but a synonym of Templeton's. Nine 

 new species are described, chiefly from Sumatra, Java, and 

 Japan : one, M. musicus, is described as living in the 

 high mountain forests at Java, and is said to make a 

 sharp interrupted noise during the night. The natives 

 call it " tjatjing sondarie." 



If in calling attention to these important contributions 

 to our knowledge of the treasures of the Leyden Museum 

 we have passed over the very numerous contributions to 

 entomology, it is simply because our space forbids us 

 referring to the immense number of new genera and 

 species herein described ; indeed these notes form a 

 perfect magazine of entomology, and we feel sure are 

 long ere this quite well known to all our entomological 

 readers. 



PRZEVALSKY'S WILD HORSE 

 f~* REAT interest is attached to the question of the 

 ^-* origin of our domestic animals, and especially to 

 that of the horse — which is generally supposed not now 

 to exist in an aboriginally wild state. Every fact bearing 

 upon this subject is of importance, and the discovery by 

 the great Russian traveller, Przevalsky, of a new wild 

 horse, more nearly allied to the domestic horse than any 

 previously known species, is certainly well worthy of 

 attention. 



The horses, which constitute the genera Equus of 

 Linnams, and are the sole recent representatives of the 

 family Equidcc, fall naturally into two sub-genera, as was 

 first shown by Gray in 1825 (Zoo/. Jonrn. i. p. 241) — 

 Equus and Asinus. 



The typical horses (Equus) are distinguishable from 

 the asses (Asinus) by the presence of warts upon the hind- 

 legs as well as upon the fore-legs, by their broad rounded 

 hoofs, and by their tails beginning to throw off long hairs 

 from the base, instead of having these hairs confined, as 

 a sort of pencil, to the extremity of the tail. Up to a 

 recent period all the wild species of Equus known to 

 science were referable to the second of these sections, 

 that is, to the sub-genus Asinus, known from Equus by 

 the absence of warts or callosities on the hind-legs, by the 

 contracted hoofs, and by the long hairs of the tail being 

 restricted to the extremity of that organ. Of this group 

 the best known species, commonly called wild asses and 

 zebras, are (1) the wild ass of Upper Nubia (Equus 

 tceniopus), probably the origin of the domestic ass ; (2) 

 the wild ass of Persia and Kutch (E. onager) ; (3) the 



hemippe or wild ass of the Syrian Desert E. lieniippus) ; 

 (4) the kiang or wild ass of Tibet (E. hemionus) ; (5) the 

 quagga (E. quagga) of South Africa ; (6) the Burchell's 

 zebra (E. burchelli) of Southern and Eastern Africa ; (7) 

 the zebra (E. zebra) of Southern Africa. As already 

 stated, these seven animals all possess the characters of 

 the second sub-genus Asinus as above given, and no 

 recent species of horse referable to the first sub-genus 

 (Equus) was hitherto known to exist on the earth's sur- 

 face, except the descendants of such as had been formerly 

 in Captivity. 



Under the circumstances great interest was manifested 

 when it was known that Przevalsky, on his return from 

 his third great journey into Central Asia, had brought 

 back with him to St. Petersburg an example of a new 

 species of wild horse, which belonged, in some of its 

 characters at least, to true Equus. 



This new animal was described in 188 1 in a Russian 

 journal by Mr. J. S. Poliatow, and dedicated to its dis- 

 coverer as Equus prsevahkii. 



The recently issued German translation of Przevalsky's 

 third journey ' enables us to give further particulars of 

 this interesting discovery. 



Przevalsky's wild horse has warts on its hind-legs as 

 well as on its fore-legs, and has broad hoofs like the true 

 horse. But the long hairs of the tail, instead of com- 

 mencing at the base, do not begin until about half-way 



aUkyV 



down the tail. In this respect Equus przevulskii is in- 

 termediate between the true horse and the asses. It also 

 differs from typical Equus in having a short, erect mane, 

 and in having no fore-lock, that is, no bunch of hairs in 

 front of the mane falling down over the forehead. Nor 

 has Przevalsky's horse any dorsal stripe, which, although 

 by no means universal, is often found in the typical horses, 

 and is almost always present in the asses. Its whole 

 general colour is of a whitish gray, paler and whiter be- 

 neath, and reddish on the head. The legs are reddish 

 to the knees, and thence blackish down to the hoofs. It 

 is of small stature, but the legs are very thick and strong, 

 and the head is large and hea\y. The ears are smaller 

 than those of the asses. 



Przevalsky's wild horse inhabits the great Dsungarian 

 Desert between the Altai and Tianschan Mountains, 

 where it is called by the Tartars " Kertag," and by the 

 Mongols " Statur." It is met with in troops of from 

 five to fifteen individuals, led by an old stallion. Ap- 

 parently the rest of these troops consist of mares, which 

 all belong to the single stallion. They are lively animals, 

 very shy, and with highly-developed organs of sight, 

 hearing, and smelling. 



They keep to the wildest parts of the desert, and are 



1 " Reisen in Tibet und am oberen Laut des Gelben Flusses in den Jahren 

 1870 bis 1880," von N. von Prschewalski. Aus den Rusaischen frei in d.t 3 

 Deutsche iibertragen von Stein-Nordheim. (Jena, 1884.) 



