4. BiTFo. 285 



Tympanum absent ; no tarsal fold ; first 



finger not longer than second 18. variegatus, p. 293. 



Tympanum distinct, half the width of 



the eye 23. halophilus, p. 295. 



Inner metatarsal tubercle very large, 



shovel-shaped 33. eompcoctilis, p. 302. 



Tympanum hidden ; no tarsal fold ; first 



finger longer than second 84. simus, p. 302. 



Tympanum distinct, very small; paro- 



toids short 35. spinulosus, p. 302. 



3. Toes entirely webbed, or nearly so. 



Skin perfectly smooth 15. politus, p. 292. 



Skin warty 24. hm-eas, p. 296. 



B. Head with bony ridges. 



1. A tympanum. 



a. Upper eyelid normal. 



a. Supraorbital and postorbital ridges straight, forming 

 together a right angle. 



* Derm of head free from cranial ossification. 

 Parotoids close to the eye ; metatarsal 



tubercles blunt 43. intermedins, p. 307. 



Parotoids close to the eye ; metatarsal 



tubercles shovel-shaped 44. dipternus, p. 308. 



Tympanum large, very distinct 45. hntiginosus, p. 308. 



Tympanum small; toes nearly entirely 



webbed 46. occipitalis, p. 310. 



Tympanum hidden 54. hoeourtii, p. 314. 



Tympanum distinct, half the size of the 



eye ; toes extensively webbed 64. coniferus, p. 321. 



** Derm of head involved in cranial ossification. 



Tympanum at least half the width of the 



eye 74. peltoeephalus, p. 325. 



Temporal region entirely bony, the tym- 

 panum being a mere foramen perfora- 

 ting a shield of bone 75. empusiis, p. 326. 



/3. Supraorbital and postorbital ridges forming together 

 a more or less regular curve, with the parietal 

 ridges (if present) a ;^-shaped figure. 



* Edge of the upper jaw 



strongly dUated hori- 

 zontally 68. d'orhignyi, p. 322. - — 



*'* Angles of jaws projecting. 59. typJionius,'^.3V7. ^- 



