On Tioo neio Frogs from Cameroon. 261 



larger eye (diameter 4 times in length of head, equal to length 

 of snout, and considerably greater than the distance from 

 posterior edge of prseoperculum in specimens of this size), the 

 smaller scales (75-90^^^), and the much more anterior vent. 

 C. argenteus is quite as closely allied to C. ensiferus, Poey, 

 which has larger scales (50-60) and a longer pectoral, and 

 also differs in many other characters. There can be no 

 doubt as to the identity of C. mexicanus^ Bocourt, with 

 C. parallelus. The British Museum possesses several ex- 

 amples from Mexico, in some of which the lateral line is 

 more or less pigmented. C. constantinus, Jord. & Everm., 

 appears to me to be at least very closely allied to C. un- 

 decimalis, Bl., a species with which they do not compare it. 



XXXII. — Descriptions of Two new Genera of Frogs of the 

 Family Ranidse from Cameroon, Bv Gr. A. BOULENGEK^ 

 F.R.S. 



Nyctibates. 



Pupil vertical. Tongue cordiform, free and notched 

 behind. Vomerine teeth. Tympanum distinct. Fingers 

 free^ toes webbed. Outer metatarsals bound together. Omo- 

 sternum and sternum cartilaginous. Terminal phalanges 

 simple, obtuse. 



Closely related to Trichohatrachus, Blgr. 



Nyctihates corrugatus. 



Vomerine teeth in two small rounded groups between the 

 large choanfe. Head large, as long as broad ; snout as long 

 as the orbit, obliquely truncate and slanting forwards from 

 the nostrils to the mouth ; canthus rostralis strong ; loreal 

 region concave ; nostril equally distant from the eye and 

 from the end of the snout ; eye large ; interorbital space as 

 broad as the upper eyelid ; tympanum three fifths the diameter 

 of the eye. Limbs rather slender ; tips of fingers and toes 

 slightly swollen ; first finger a little longer than second ; toes 

 half-webbed ; subarticular tubercles strong ; a small, oval, 

 inner metatarsal tubercle. The tibio-tarsal articulation reaches 

 the eye. Upper parts with small granular asperities ; back 

 with fine oblique folds converging posteriorly, forming more 



