RENDAHL, BIRDS FROM PANAMA, COSTA RICA AND NICARAGUA. 13 



Carriker (1. C. page 395) described the Costa Rica birds 

 as belonging to a separate subspecies, Oe. nigrirostris brun- 

 neicauda, åiUeviug iYom tnie nigrirostris »in its smaller size, 

 deeper vinaceous tint of under parts, in baving tbe under 

 tail-coverts concolour witb tbe abdomen. True nigrirostris 

 from Britisb Honduras bas tbe tail decidedly sooty grayisb, 

 wbile tbe coverts are bluisb slate, tipped witb bluisb vina- 

 ceous. In Costa Rica birds tbere is only a sligbt amount 

 of bluisb at tbe base of tbe featbers, or none. Tbe Costa 

 Rica birds bave tbe basal two-tbirds of the inner web of 

 three outer rectrices brigbt russet-brown, wbile in true nigri- 

 rostris tbere is only a trace of brown. Tbe new form bas 

 the upper parts paler and more olive-brown and tbe pileum 

 brigbter witb no trace of purplish.» 



Mr. C. gives tbe following measurements: 



C. nigrirostris nigrirostris: male, wing 161; tail 129. 



C. nigrirostris brunneicavda: male, wing 155; tail 123. 



Mr. RiDGWAY remarks (1. c. page 329) about the varia- 

 tion of Oe. nigrirostris, tbat there is a tendency among more 

 soutbern examples to a more brownisb tone of coloration, 

 but that tbe difference is far from being sufficently constant 

 to warrant their subspecific separation. 



Of course, a great material is necessary to decide, if there 

 is a distinct difference between the Costa Bica birds and 

 those from other localities, in particular if such a variable 

 character as the coloration essentially is regarded. 



Dr. Carriker unfortunately gives no informations about 

 the greatness of the material, upon which be bases bis con- 

 clusions. He only states, that the collection of the Carnegie 

 Museum contains four skins. 



The three specimens collected by Dr. Bovallius are 

 uaturally not sufficient for a critical examination; while, 

 however, the two birds from Costa Rica do not at all show 

 any distinct difference from the Nicaraguan one, I think it 

 may be of some interest to point out their relations in the 

 critical characters. 



c?, Costa Rica, Bitéi. Under tail-coverts concolor witb 

 the abdomen. 



$, Costa Rica, Bitéi. Under tail-coverts bluisb slate, 

 tipped witb bluisb vinaceous. 



