1908.] DR. KNUD ANDERSEN ON BATS. 297 



The proportionate length, of the bony palate is quite as in 

 all the foregoing species of Artibeios, the distance from palation 

 to the hinder margin of the incisive foramina being larger than 

 the distance from palation to basion (compare A. turpis and 

 nanus, chai-acterised by a shortening of the bony palate, p. 307). 



A. toltecus and aztecus. — The difference between these two 

 species is pointed out below, p. 306. 



mg in A. toltecus. — In one skull, out of 27 examined, va..^ is 

 present on the right side, entirely wanting on the left ; the 

 individual is a young adult male of A. t. ravus (Brit. Mus. 

 no. 1.6.5.6). In all the other skulls representing both races and 

 different ages, from immature to very old, nig and its alveoli are 

 wanting. 



Wings. — The wing-structure very closely resembles that of 

 A. cinereus, the only appreciable difference being the slightly 

 shorter proximal phalanges of the third, fourth, and fifth digits ; 

 in A. cinereus the indices of these phalanges are, respectively, 

 357, 304, and 239, in A. toltecus 342, 289, and 227. For further 

 details see the wing-indices on p. 310. 



Hairing on limbs and membranes. — As in A. cinereus, but the 

 upper side of the interfemoral moi-e strongly haired, the fur 

 forming a distinct fiinge along the posterior margin of the 

 membrane. 



Coloicr. — See A. t. toltecus (p. 298) and A. t. ravus (p. 300). 



Range. — From IST. Ecuador to Central Mexico (Durango), but 

 Ecuador individuals [A. t. ravus) differ in some respects from 

 Central American and Mexican individuals {A. t. toltecus). 



Artibeus toltecus toltecus Saussure. 



I860. Stenoderma tolteca H. de Saussure, Rev. & Mag. de Zool. (2) xii. pp. 427-28, 



pi. XV. fig. 4 (Oct. I860).— Type locality : Mexico. 

 1878. Artibeus cinereus (not Gervais) Dobsoii, Cat. Chir. Brit. Mus. pp. 520- 



21. — Costa JRica, Guatemala, Mexico. 

 1882. Artibeus cinereus (not Gervais) Thomas, P. Z. S. p. 371. — Durango (Mexico). 



Diagnosis. — Averaging larger : forearm 3 9-43 '5 mm. Facial 

 stripes and white edgings to the ears as a rule wanting or 

 indistinct, rarely well developed. 



A. t. toltecus and ravus. — A. t. toltecus can only be discriminated 

 from A. t. ravus by average characters. The skull of A. t. toltecus 

 averages in every respect a trifle larger (especially broader), but 

 small skulls of toltecus are indistino'uishable from laro-e skulls 



o 



of ravus. The external dimensions avei-age larger, the forearm 

 and metacarpals being from 2"7 to 3'2 mm. longer. As in 

 A. t. ravus there is a dark and a light phase, but the dark phase 

 in A. t. toltecios is noticeably darker than in any specimen I have 

 seen of A. t. ravus. In most specimens of A. t. ravus, both in 

 its dark and light phase, the facial stripes and light edgings to 

 the ears are sharply pronounced ; in A. t. toltecus they are but 

 rarely well marked, as a rule indistinct or quite undeveloped. 

 From this it will be seen that it is impossible to draw a 



