^.OO Ci.\KK, Black-v;ing-ed Palm Tanager. \_oti 



with the next shortest come from Trinidad, while Margaritan 

 birds have the longest of any, with the exception of Peruvian 

 examples. Costa Rican birds are close to those from the lower 

 Amazons. 



By, dividing length of wing by length of tail, we obtain a ratio 

 between the two. An examination of these figures shows that 

 Peruvian birds have the longest tails proportionately, while those 

 from Trinidad have the shortest. Specimens from middle north- 

 ern Venezuela (Santa Marta, Yacura, and Margarita) and from 

 Costa Rica are intermediate. Those from Panama resemble most 

 closely Trinidad examples, while the lower Amazonian form agrees 

 with the Costa Rican. 



In regard to the length of the chord of the culnien, birds from 

 Yacura, Margarita, and Trinidad exceed all others. Guianan and 

 Costa Rican specimens agree in having very short beaks, while 

 those from Peru, Panama, and the lower Amazons are intermediate. 



Tarsal measurements show that Costa Rican and lower Ama- 

 zonian birds are identical in this character; while Trinidad and 

 Peruvian birds are pretty close, having the longest tarsi. Panama 

 specimens have shorter tarsi, agreeing with those from Guiana ; 

 Santa Marta and Yacura ones have the least of all, while the 

 Margaritan form is intermediate between them and the bird of 

 Trinidad. 



In measurements the true T. pahnarum palmarum from south- 

 eastern Brazil is larger than the average of the subspecies inelan- 

 optei-a examined in respect to length of wing, culmen, and tarsus ; 

 but in tail measurements it is near the Santa Martan bird. The 

 ratio between length of wing and length of tail is that of Trini- 

 dadian 7nelanoptera. 



In short, then, the specimens of T. pabnanim mclanoptcra from 

 Costa Rica show a striking similarity in all dimensions to those 

 from the lower Amazons. Peruvian birds are largest, except for 

 the beak, while Trinidad birds are near them in all respects save 

 in length of tail. Guianan birds are also close, having longer 

 tails than those from Trinidad. There seems to be a regular 

 gradation from Panama along the coast to Trinidad. The most 

 striking fact is the small size of the Panama birds as compared 

 with those from Costa Rica on the west and Santa Marta and 

 Yacura on the east. 



