106 Bangs — Birds from Costa Rica and Chiriq 



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of O. calolxina C(d<il;nnn faded or discolored by some change in the feath- 

 ers, as it is said to dilfer only in its breast l)eing darker, and when viewed 

 from in front nearly black. Especially as Hartert says it occurs with true 

 0. calohema in several parts of Costa Rica. At all events, Underwood did 

 not have a specimen in his collection, and it is with the other three forms 

 that I have to deal. 



The first point to be decided is whether or not the white throat of leu- 

 canjyis as against the violet throat of (■alohcimi is a specific or subspecific 

 character, or even a character at all, and I must confers that even the large 

 amount of material I have examined does not satisfy me on tliis point. 

 The series taken on the Volcan de Chiriqui by Brown contained but one 

 individual with a violet throat ; all the others have the throat mostly white ; 

 close inspection, however, shows that there are some violet-tipped featliers 

 at the edge of the white i)atch in nearly every one of these white-throated 

 birds. Among the Costa Rican skinsof O. ca/o/.-em« I find none but violet- 

 throated birds. These are mostly from Irazu and Cerro de la Candelaria. 

 0. civereicaurhi, that occurs chiefly (if not exclusively) in the Dola Moun- 

 tains in central Costa Rica, between the Volcan de Chiriqui and Iiazu and 

 the Cerro de la Candelaria, has the throat usually mixed violet and white ; 

 out of (53 males, 33 have the throat violet and white mixed, in some nearly 

 half and half, and 30 have plain while throats. Otherwise clnerek'uudd is 

 not in the least intermediate between odalanna and Icucaajjin, but differs 

 widely from both in its gray tail and bluer crown. 



Examining the feathers of the throat carefully, we find them in tlie 

 white-throated specimens to be gray at base then pure white to ends, in 

 both leucaspis and civrreirnuda. In the one violet-throated bird from tlie 

 Volcan de Chiriqui, the feathers are gray at base, then white in middle 

 and merely tipped with violet. In calohema from Costa Rica the gray 

 bases of the feathers extend U})wards to the violet lips and there is no 

 white middle part to the feathers of the throat. I therefore think that the 

 violet-throated birds (either with the throat wholly or partially violet) from 

 Chiriqui are merely cases of extreme individual variation of 0. leucasjns. 



White-throated examples with steel blue tails, i. e., 0. leucaKpis, are only 

 known from tlie Volcan de Chiriqui, and even here some examples have 

 the throat violet. As I have said before, however, all Costa Rican skins 

 have the throat violet. 



I have seen no specimens from the Veraguan Ranges. Salvin, however, 

 records violet-throated birds from the western ranges — Cordillera del 

 Chucu, Cordillera de Tole, etc. — which he calls, together with the violet- 

 throated ones from Volcan de Chiriqui, 0. adolxma. I am unable to say 

 if these have white below the violet, or if they are like Costa Rican speci- 

 mens and have the gray of the bases of the feathers extended upward and 

 meeting the violet tips ; probably they are calolxma. In my opinion 0. 

 calola'ma. and 0. leucaxpis are exceedingly closely i-elated forms, differing 

 in exti-eme cases in one having a violet and the other a while throat, but 

 in many instances only to be told aiiart by one having white below the 

 violet tips of the feathers of the throat and liic oilier gray, and I should 

 treat them only as 8ubsi)ecies at the best. 



