Todd-Carriker : Birds of Santa Marta Region^ Colombia. 313 



the purer gray back of the male, with little black showing through. 

 The under parts are neutral gray, with the abdomen appreciably paler. 

 The female is sepia above, the pileum and tail Brussels brown in sharp 

 ■contrast, and dull bufify whitish below. 



The Costa Rican and Panama birds, which were distinguished by 

 , Salvin and Godman under the name atrinucha, are readily recogniz- 

 able by their larger bills, the culmen averaging about 19.5, although 

 ■otherwise the size is the same. The under parts in the male are darker 

 gray, with more or less black spotting or barring on the throat and 

 breast ; the upper parts, too, are darker, and the black is decidedly more 

 extensive and prominent, sometimes prevailing over the gray. The fe- 

 male is much more deeply colored throughout than the same sex of 

 ' punctatus ; the pileum and tail are duller, scarcely in contrast with the 

 back; the under parts are strongly washed with light brownish olive. 



It would naturally be expected that Santa Marta specimens would be 

 intermediate between these two perfectly distinct races, but such does 

 not prove to be altogether the case. Considering males first, we find 

 that the bill averages as large as in atrinucha, while the general colora- 

 tion is paler gray than in punctatus, the entire under surface being 

 of about the same shade as the abdomen in that form. Only in the 

 amount of black mottling on the back is this form intermediate be- 

 tween punctatus and atrinucha. The series of females vary among 

 themselves to such an extent that it is difficult to say just what should 

 be considered the normal phase of coloration ; they are all duller, how- 

 ever, than those of punctatus, but not so dark as a rule as those of 

 atrinucha. It appears, therefore, that the Santa Marta form is worthy 

 of recognition, and it wa? accordingly provided with a name by the 

 writer in 1915. The description of Thamnophilus gorgoncs Thayer 

 and Bangs {Bulletin Museum of Comparative Zoology, XLVI, 1905, 

 95) seemed at the time to preclude the possibility of such being the 

 same form, but actual comparison proves otherwise. Males from Gor- 

 gona Island differ from Santa Marta examples only in having a little 

 n7ore gray feather-tipping on the forehead- — a dififtrence of no conse- 

 quence. Females from the same locality are very uniform in being 

 more richly colored, deeper buffy below, and more rufescent above, 

 than the majority of Santa Marta examples of that sex, but they are 

 matched so absolutely by several of our specimens that their separa- 

 tion would not be justified, at least on the basis of present material. 



