AMPHIBIANS 1 71 



di Cranial crests sharp-edged and high B. valliceps. 



do Cranial crests thick, confluent between the nostrils B. cognatus. 



ds Cranial crests curved around the eyes B. aharius. 



bs On the Pacific slope. 



Ci With a light middorsal line; skin rough B. boreas. 



c-i Without a light middorsal line; skin very smooth B. canorus. 



B. amcricanus Holbrook. Common toad (Figs. 81 and 83). Body 

 heavy and squat and variable in color, being usually gray or yellowish 

 brown, more or less mottled or spotted; throat of male black; under 

 parts white, spotted; parotoids elongate and reniform; cranial crests 



Fic;. 83. — Under surface of Bufo amcricanus {from Dickerson). 



divergent; length 70 mm.; hind leg 85 mm.; female much larger: North 

 America east of the Rockies; northward to Hudson Bay and Great Bear 

 Lake. 



B.Jowleri Garman. Common toad (Fig. 84). Body rather slender, 

 greenish or yellowish gray in color, spotted or striped with brown ; under 

 parts white; throat of male black; parotoids narrow and not reniform; 



