228 BATRACHIA SALIENTIA. 
and others. No doubt the two forms are very closely allied, but in H. sallwi the 
greater part of the abdomen is granular, while in all the notes by Cope this part 
of the skin is represented as smooth. ‘There is, of course, the possibility that in 
consequence of the imperfect preservation the granulation has disappeared or become 
indistinct in Cope’s specimens, asI myself have noticed in some examples, particularly 
in the one obtained by Salvin in Vera Paz; however, closer examination under a lens 
reveals the areolated condition of the skin. 
If these specimens be referred to the smooth-bellied LZ. rhodopis, the structure of 
the skin of the abdomen, used by Cope for the generic discrimination of Lithodytes 
and Hylodes, and by Boulenger for division of the species into groups, would cease to 
be a help even for specific distinction. 
2. Hylodes plicatus, sp.n. (Tab. LXVI. fig. B.) 
Hab. Mexico, Jalapa (Mus. Brit.). 
A very distinct fold across the chest, separating the smooth throat from the granular 
abdomen. Habit rather slender; snout somewhat acuminate, with sharp canthus 
rostralis and subvertical sides. Tympanum as large as the eye (in a male). Vomerine 
teeth in two small groups, well separated from each other, behind, but within the level 
of, the choane. Skin of the upper parts smooth, with the exception of two pairs of 
exceedingly fine, curved, dorsal folds; another fold above the tympanum. Disks 
of the fingers and toes very small; first finger a little longer than the second. 
Two small metatarsal tubercles; series of subarticular tubercles continued on the 
metatarsus; no tarsal fold. The length of the body is almost equal to the distance 
between vent and heel. Light brownish-olive above, with a dark interorbital band ; 
hind limbs cross-barred. A black band runs from the nostril through the eye to 
above and round the tympanum; vent black. Lower parts white. 
Length of body . . . . . 1 . 1 eee ee 6 19°5 millim. 
Distance between vent and heel . . . . . . . . 205 ,, 
3. Hylodes polyptychus. (Tab. LXVI. fig. C.) 
Hylodes polyptychus, Cope, Proc. Am. Phil. Soc. xxiii. p. 276 (1886). 
Hylodes steinegerianus, Cope, Proc. Am. Phil. Soc. 1894, p. 338. 
Hab. Nicaracua, Hacienda Rosa de Jericho, ait. 3250 feet (Rothschuh) ; Costa Rica, 
La Palma (Underwood). 
Habit moderate, the length of the body being nearly equal to the distance between 
vent and heel. Snout rather short, with distinct canthus rostralis and subvertical sides. 
Tympanum nearly the size of the eye in males, but smaller in females. Vomerine 
teeth in two short oblique series, well separated from each other, starting from the 
