MEXICAN TAILLESS AMPHIBIANS 193 



golden, bronzed, or grayish; sides of body paler than back 

 and variously spotted or marbled with black; upper surfaces 

 of limbs with large dark spots, or with continuous or inter- 

 rupted dark cross bands; hinder surface of thighs yellow or 

 grayish white, vermiculated, marbled, or spotted with black, 

 or else black with reddish-yellow spots; underparts white or 

 yellow; throat and chest often spotted, marbled, or mottled 

 with gray or brown; longitudinal dark streak or dark mar- 

 bling may or may not be present on anterior surface of thigh; 

 fingers obtusely pointed, sometimes bordered by feeble lateral 

 fringe; first finger equal to or longer than second; the hind limb 

 being carried forward along the body, the tibio-tarsal joint 

 reaches to eye or to end of snout, or a little beyond, and usually 

 to between eye and end of snout; distance from snout to vent 

 iVs to 2 times length of tibia; toes obtusely pointed, two-thirds 

 to nearly entirely webbed, usually two phalanges of fourth free, 

 occasionally one or three; outer metatarsals separated nearly 

 to base; subarticular tubercles rather small, moderately prom- 

 inent; tarsal fold distinct, feeble, or absent; inner metatarsal 

 tubercle narrow, more or less prominent, or compressed, one- 

 third to one-half the length of inner toe; outer metatarsal 

 tubercle absent, or small and indistinct; width of head at level 

 of posterior angles of jaws generally less than distance between 

 end of snout and posterior margin of tympanum ; snout rounded 

 or obtusely or acutely pointed, projecting more or less beyond 

 the mouth, and as long as or longer than the transverse diam- 

 eter of eye; canthus rostralis distinct or obtuse; loreal region 

 oblique, feebly concave; nostril equidistant from eye and 

 from end of snout, or a little nearer the former; interorbital 

 width one-third to once that of upper eyelid; tympanum very 

 distinct, smooth surfaced, and one-half to three-fourths diam- 

 eter of eye; vomerine teeth in short transverse or posteriorly 

 converging oblique groups usually between the choanae (fig. 

 24), occasionally on a level with their posterior borders, or 

 extending a little beyond their level, and rarely on a level with 

 their anterior borders; male with vocal vesicles internal, or 

 more or less developed externally, but not retractile, forming 

 a flabby pouch behind angle of mouth and above arm; head- 

 and-body length of adults, 65 to 110 mm pipiens (p. 203) 



Skin of back between dorso-lateral glandular dermal folds with- 

 out elongated warts or glandular ridges 5 



Tips of fingers swollen; vomerine teeth in oblique posteriorly 

 converging rows, the apex of which projects behind level of 

 posterior borders of choanae; head broader than long, rather 

 strongly depressed; snout rounded, scarcely projecting beyond 

 the mouth, as long as transverse diameter of eye; canthus ros- 

 tralis distinct; loreal region moderately oblique and deeply 

 concave; nostril a little nearer to end of snout than to eye; 

 tympanum very distinct, its transverse diameter less than 

 half that of eye; first finger longer than second; the hind limb 

 being carried forward along the body, the tibio-tarsal joint 

 reaches to between eye and end of snout; distance from snout 

 to vent 1% times length of tibia; toes with tips swollen 

 into small disks, webbed to tips; outer metatarsals separated 

 nearly to base; subarticular tubercles rather large and promi- 



