94 BULLETIN 13, UNITED STATES NATIONAL MUSEUM. 



This variation differs markedly iu coloratiou froui any bat of the 

 genus in the ftuina. This alone should retain the form. It holds rela- 

 tively the same position as the preceding variation and V. nitidus 

 longicrxs. 



3. Vespertilio nitidus H. Allen. The Califoruiaii Bat. (Plate xiij. 



VeapertUio nitidus H. Allen, Proc. Aead. Nat. Sci. Phila., 1862, 247: Monoj;-. Bats N. 



A., 1864, 60; Dobson. Cat. Chirop. Brit. Mus., 1878, 318; Alston, Biol. Centrali- 



Amer. Mam., 1879-1882, 24. 

 Vesperltlio agiJis H. Allen, Proc. Acad. Nat. Sci. Phila., 1866, 279. 

 Vespertilio volaiis H. Allen, Proc. Acad. Nat. Sci. Phila., 1866, 279. 

 Vespertilio californicus ( ?), Bachman, Journ. Acad. Nat. Sci., Phila., 1842, 280; Peale, 



V. S. Explor. Exped. (Mam.), 1858, 3. 



IHagnosh. — Ears much as in Y. gryphns; the tirst scalloi) equals in 

 length the external border and tip; the external basal lobe tends to be 

 higher than broad ; the outer border of the tapering tragus convex at 

 lower half disposed to be crenulated, the outer and inner border never 

 forming the sides of an isosceles triangle. Tail ample, convex on lower 

 margin. Tail subtriangular or obovate below the level of the ankles 

 and the tip exsert only in the pedomorphic forms. The first metacar- 

 pal bone parallel to the second.* 



It is a question whether Y. californicus Bachman {vide Appendix) 

 should be accepted as a name for this species. 1 have concluded that 

 the description does not sufficiently identify it. It is simply known to 

 have been a Avestern bat (for the Avord californicus need not necessarily 

 have meant in 1842 the State of California as now restricted) having 

 vespertilionine features as shown in the " sharp nose" and "linear at- 

 tenuated tragus." The "light yellowish-brown" fur suggests that it 

 may be the same as T". nitidus macropus. Since the type sijecimen is 

 lost I have thought best not to attempt to rehabilitate this species. 



Description — Dorsum light or dark chestnut brown with individual 

 variations of olive brown, tawny, or gray colors. The base of the hair 

 is of a deep black except at the rump where it is unicolored. The 

 sparse hair on tlie back of the interfemoral membrane usually extends 

 as far as the level of the feet; it is occasionally confined to the region of 

 the basal third of the tail. The under surface of the body is of a lighter 

 shade of brown than the dorsum. The gray tints gradually increase 

 fr(im above downward and are conspicously developed at the pubis in 

 some specimens. In the most marked exami^les of this tendency it 



*Alstoii (Biol. Centrali-Amer., 1879-1882, 24) gives the following differential diag- 

 nosis between V. nitidus, V. niriricans, and V. lucifuf/us. 



V. nitidus. — Ears as long as head; muzzle slender, pointed; thumb shorter than 

 foot, which is small ; tail wholly included iu membrane. Forearm 1". 20'". Fur red- 

 dish brown above; reddish gray l)eneatli. 



J', nigricans. — Ears shorter than head ; muzzle obtuse ; thumb as long as foot. Fore- 

 .arm 1". 30'". Fur sooty rust-color. 



V. lucifugus.—EsLis as long as head, Foveurm 1," 40,'" Fur olive-brown, grayish 

 below, 



