| OCR Text |
Show 134 MR. O. THOMAS ON A NEW GENUS OF MURIDAE. [Feb, 21, with the Old-World Hamsters under the nan e of Cricetus, tbe latter group, however, forming itself a subgenus, equal in rank to those now commonly admitted among the American Vesper-Mice. This change, large as it is, will be rendered rather less unacceptable by the con-ideration that the name Hesperomys1 has itself, by the strict laws of nomenclature, no possible claim to adoption, being antedated not only by Calomys2, Waterh., and the other earlier names of the same author, and by Eltgmodontia, F. Cuv.3, but also by Akodon, Meyen \ founded on a now almost unrecognizable specimen belonging to Waterhouse's subgenus " Habrothrix." That this name would have been brought up and forced into use may be looked upon as certain, and in fact the first step in this direction has been taken by the substitution of Akodon for Habrothrix in Trouessart's list of Rodents5. From the point of view of nomenclature, therefore, the junction of Cricetus and Hesperomys is not so wholly a misfortune as it otherwise might have been. As to changes in specific names, it fortunately happens that those used in the two genera have for the most part been different, the two species mentioned in the subjoined footnoteB representing apparently all the necessary alterations. Then as to the geographical distribution of the two forms, nothing is more natural than that a genus ranging all over America, from British Columbia to Cape Horn, should also he found, like the majority of the m o t typical North-American genera, in Siberia, China, and the Eastern Palaearctic Region generally. With regard to the opinions of other authors ou the relations of Cricetus to Hesperomys, it is interesting to find that in Dr. Winge's, recent careful and elaborate work 7 on the Rodents of Lagoa Santa, Brazil (a work in which the whole interrelations of the Rodents are freshly considered and described), the differences between Cricetus and Hesperomys are shown to be almost nil8, and that in the Synopsis of the Muridae he has had to separate the genera merely into those from the Old World and those from the New 9. He does not, however, notice the necessity for actually uniting Cricetus with Hesperomys, no doubt because of the very different standard of generic rank he adopts. Thus he recognizes the well-known subgenera Habrothrix, Oxymycterus, Scapteromys, Calomys, and Rhipidomys all as full genera, and therefore naturally admits Cricetus also. I 1 Zool. Voy. «Beagle,' M a m m . p. 75 (1839). 2 P. Z.S. 1837, p. 21. 3 Ann. Sci. Nat. vi. p. 168 (1837). 4 N. Act. Ac. Leop. xvi. p. 600 (1833\ 5 Bull. Soc. Sci. Anvers, 1880, p. 140. c Cricetits obscurus, M.-Edw., nee Hesperomys obscurus, Waterh., may stand as C. monyolicus. Cricetus longicaudatus, M.-Edw., nee Hesperomys longicaudatus, Benr., as chinensis. Cricetus cinereus, Gerrard, Cat. Bones M a m m . B.M. p. 172 (1862), appears never to have been described, and does not therefore invalidate' the specific name of my Cricetus {Thomasumys) cinereus, P.Z.S. 1882, p. 108. 7 E Museo Lundii, vol. iii. 1887. 3 B.C. p. 11. 8 L.c. p. 125. |
