36 



ARKIV FÖR ZOOLOGI. BAND 13. N:0 4. 



The Northern Elaenia was not collected by Dr. Bovallhjs. 



Thayer and Bångs say, that there appear to be no con- 

 stant differences between the island skins and those from 

 Panama mainland and Chiriqui, but that the olive green of the 

 back varies considerably, so me specimens being very påle. 

 RiDGWAY remarks (op. cit. pag. 430, foot-note) that most of 

 the specimens examined by him from Saboga and some of 

 those from the vicinity of Panama City are paler and very 

 much grayer on the upper parts than others even more so 

 than E. m. flavogastra. «It is possible they may represent a 

 form worthy of recognition. » 



According to Bångs a young in nestling plumage was 

 taken on May 2nd. 



54. Elaenia chiriquensis sordidata (Bångs). 



Elcenia sordidata Bångs, Auk. XVIII. 1901. 28 (San Miguel; type). 

 Elainea albivertex sordidata Thayer and Bångs. Bull. Mus. Comp. Zoöl. 



XLVI. 1905. 152 (San Miguel). 

 Elcenia chiriquensis sordidata Kidgway, Birds North Middle Am. IV. 1907. 



433 (San Miguel). 



BovALLius' Collection: 2 ??, Viveros, April 5 and 11. 



RiDGWAY refers this form in his key to the species and 

 subspecies of Elaenia (op. cit, p. 425) to a group characterized 

 by having «throat and chest more or less olivaceous or yel- 

 lowish, not contrasting with color of abdomen». As to A. 

 chiriquensis he then adds: «throat more grayish». Such a 

 classification seems to me to be misleading. At least in the 

 present specimens the chest, being between smoke-gray and 

 light drab, is in distinct contrast with the påle yellow of ab- 

 domen. 



Measurements : 



The outer most pair of rectrices are on outer web, edged 

 with ivory yellow, in one of the specimen (Apr. 5) whole. The 

 basal half of outer web is shaded with this color. 



Iris as noted on labels, grayish blue. 



