13. LEPTODACTTWJS. 245 



width of the eye. Toes without dermal margins. The hind limb 

 being carried forwards along the body, the tibio-tarsal articulation 

 reaches the posterior border of the orbit. Dorsal skin without 

 glandular folds ; an abdominal discoidal fold. Colour above dark 

 brown, with a blackish pale-edged triangle between the eyes, with 

 its apex directed posteriorly ; a dark light-edged spot below the 

 front of the orbit; tympanum and a streak behind it blackish. 

 Guanajuato, Mexico. 



13. Leptodactylus perlaBvls. 



Cystignathus perlaevis, Cope, Proc. Amer. PMlos. 8oe. xviii. 1879, 

 p. 260. 



Tongue a longitudinal oval, entire. Vomerine teeth in two short 

 transverse series behind the choanoc. Snout a little projecting, with 

 distinct canthus rostralis, the nostrils about one third the distance 

 from its apex to the orbit ; tympanum not quite two thirds the 

 width of the eye. Eirst finger a little longer than second ; foot 

 slender ; plantar tubercles insignificant. The hind limb being carried 

 forwards along the body, the tibio-tarsal articulation reaches in 

 front of the eye. Skin exceedingly smooth and shining, without 

 glandular folds ; an abdominal discoidal fold. Dark ashy grey 

 above ; sides blackish above, speckled with white and blackish 

 above ; an interorbital dark spot ;. upper lip marbled ; posterior face 

 of femora dark, with light specks ; posterior limbs obscurely cross - 

 banded. 



Tehuantepec. 



14. Leptodactylus albilabris. (Plate XVI. fig. 4.) 



Oystignathus albilabris, Giinth. Ann. ^ Mag. N. H. (3) iv. p. 217; 



Meinh. 8r lAitk. Videmk. Meddel. 1862, p,'205. 

 " — caliginosus, Brocchi, Bull. Soc. Philom. (7) i. p. 180. 

 labialis, Cope, Proc. Amer. PMlos. Soc. xvii. p. 90, caul xviii. 



p. 269. 

 Leptodactylus caliginosus, Brocchi, Miss. So. Mex., Bcitr. p. 87, pi. 5. 



labialis, B{-occhi, I. c. p, 20. 



albilabris, Boideng. Bull. Soc. Zool. France, 1881, p. 38. 



Tongue oval, slightly nicked behind. Vomerine teeth in two 

 slightly curved series behind the choanae. Snout subacuminate, 

 with prominent upper lip, a little longer than the greatest orbital 

 diameter ; nostril a little nearer the tip of the snout than the eye : 

 interorbital space not much narrower than the upper eyelid; tym- 

 panum not quite two thirds the width of the eye. Eingers mode- 

 rate, first longer than second ; toes moderate, not fringed ; subar- 

 ticular tubercles well developed ; sole with regular series of small 

 tubercles corresponding with the metatarsals ; two small metatarsal 

 tubercles. The hind limb being carried forwards along the body, 

 the tibio-tarsal {irticulafcion reaches the eye, or not quite so far, 



