4 



Papers from the Department of Marine Biology. 



Eleutherodactylus auriculatus (Cope). Figure 2. 



Collected 21 examples from the junction of the Arecibo and Tanama 

 Rivers on June 9. This little amphibian is extremely variable in color. 

 Some individuals are pale or very light, others dark, and some of all ages 

 with a narrow whitish vertebral line. Four extremes of color-variation are 

 represented in the accompanying figures of the dorsal surface. 

 ^All the examples with the narrow whitish vertebral line (4 individuals) 

 show it bifurcate and extending out on each side of the hind femoral surface 

 toward the under surface of the knee. The larger of these examples are^also 



Fig. 1. — Leptodactylus albilabris (Giinthcr). A to E, variation in dorsal color — pattern of 

 examples of all ages from Arecibo and Tanama River Junction. 



