MEXICAN TAILLESS AMPHIBIANS 



47 



42 individuals, it would seem that the development of the cranial 

 crests is too unreliable a character to have much of a diagnostic value. 

 Fourteen of the specimens examined have no vestiges of cranial crests 

 on top of the head. When present, the postorbital crests are generally- 

 thick and blunt-edged. The supraciliary crests are often but faintly- 

 indicated, though they may be quite prominent on some individuals. 

 When supraciliary crests are developed, the interorbital region seems 

 more strongly concave than those without such crests. 



In two instances the tympanum was covered with a tubercular 

 skin, and on the others it was distinctly outlined and covered with a 

 smooth skin. In the majority of the specimens examined, the paro- 

 toid gland was separated from the upper eyelid by the blunt-edged 

 transverse postorbital crest. On two individuals (U.S.N.M. Nos. 

 47245 and 26596), however, the parotoid glands are almost in con- 

 tact with the upper eyelids, and there are no vestiges of the postor- 

 bital crests. One individual from McLennan County, Tex. (U.S.N.M. 

 No. 57625) has subcircular parotoid glands in contrast to the normal 

 elongate type. These glands are rarely very narrow, but they often 

 have a lateral enlargement that extends over upon the side of the 

 shoulder. 



Specimens taken in Durango and Chihuahua occasionally have the 

 underparts spotted with dark brown or black. The skin of the upper- 

 parts is strongly tubercular and is covered with low pustulose warts. 

 Brocchi's Bufo levifrons represents a variation of this sort. The 

 figure of Bufo mexicanus published by Brocchi resembles two toads 

 collected in Nuevo Leon (U.S.N.M. Nos. 46914-15) on which the 

 warts are low and flat, and the sldn feels smooth, as compared with 

 the variety named levifrons by Brocchi. Variations such as these 

 may be expected in this species. This species has a conspicuous 

 palmar callosity and a large shovellike inner metatarsal tubercle. 



Specimens examined. —Ninety-eight, as follows : 



Bufo compactilis 



Museum 



Locality collected 



Date collected 



By whom coDected or 

 from whom received 



M.C.Z. 



F.M.N.H..-. 

 U.S.N.M 



Do 



Do 



Do 



Do. 



Do.. 

 M.C.Z_. 



U.S.N.M. 

 Do... 



Sonora: No definite locality 



Chihuahua: 



Colonia Garcia 



Colonia Garcia (near). 



Encinillas 



Guadalupe y Calvo... 

 Meadow Valley 



Mar. 23, 1903 



Aug. 17, 1902 

 July — , 1899 

 Oct. 20, 1852 

 Sept. 8, 1898 

 July 6, 1896 



No definite locality. 

 Coahuila: 



Jimulco 



Monclova 



Nuevo Leon: 

 Doctor Cos 



Pesquieria Grande.. 



Dec. 16, 1893 

 1880 



Apr. 20, 1891 

 Apr. — , 1853 



Ward's Nat. Sci. Estab- 

 lishment. 



S. E. Meek. 

 Nelson and Goldman. 

 Thomas H. Webb. 

 Nelson and Goldman. 

 H. H. and C. S. Brim- 

 ley. 

 John Potts. 



Nelson and Goldman. 

 Edward Palmer. 



William Lloyd. 

 D. N. Couch. 



' Cotype of Bufo speciosus. 



