nATRACIIIANS FROM WEST AFRICA 



171 



Tibio-tarsal articulation reaching the 

 eye; interorbital space as broad as the 



upper eyelid 10. ^. vannutellii, Blgr. 1898. 



Tibio-tarsal articulation reaching the 

 eye; interorbital space broader than the 



upper eyelid 11. iT. cubito-albus , Blgr. 1906. 



b. Metatarsal tubercle strong , com- 

 pressed. 



a. Vomerine teeth between the 

 choanae; tibio-tarsal articulation reach- 

 ing the eye, or between the eye and 

 the tip of the snout. 



Disks of fingers and toes small . .12. H. Johnstoniij Blgr. 1897. 



Disks of fingers and toes large. . . 13. ^. aubryi, A. Bum. 1856. 



^. Vomerine teeth behind the choanae. 

 Tibio-tarsal articulation reaching the 



shoulder 14. i?. brevipes, Blgr. 1906. 



Tibio-tarsal articulation reaching 

 the tip of the snout 15. iT. haugi, Mocq. 1902. 



2. Toes webbed to the diks of the 

 third and fifth ; metatarsal tubercle 

 oval, not compressed; head not broader 

 than long; vomerine teeth just behind 



the level of the choanae 16. ^. greshoffi, Schilth. 1889. 



C. Fingers at least one third webbed; 

 toes more than half webbed , the web 

 extending to the penultimate phalanx 

 of the fifth toe; metatarsal tubercle 

 not or but slightly compressed. 



1. Head not more than once and one 

 fourth as broad as long. 



a. Tympanum more than half the 

 diameter of the eye. 



Outer fingers one third webbed; toes 

 not much more than half webbed . . 17. H. natalensis, Smith, 1849. 



Outer fingers one third webbed; toes 

 two thirds webbed; a conical tubercle 



on the heel (tibio-tarsal articulation) 18. H. calcar atus^ Blgr. 1906. 



Outer fingers one third to half 

 webbed; toes two thirds to three fourths 

 webbed ; head considerably broader 



than long 19. iT. rufus, Reichen. 1874. 



Outer fingers fully half webbed ; toes 

 nearly entirely webbed; head but 



slightly broader than long 20. H. miLlsonii, Blgr. 1894. 



b. Tympanum not half the diameter 



