Carriker : List of the Birds of Costa Rica. 413 



This bird is evidently very rare in Costa Rica. Few specimens 

 have been recorded from that country and in all my collecting I saw 

 but three birds. A pair were shot on Laguna Grande at Bonilla, 

 November n, 1907, but no more were seen, while a single female was 

 seen and secured in the lagoon at the mouth of the Matina River on 

 November 14. When alarmed or pursued they dive and swim for 

 long distances under the water, but do not remain under as long as the 

 grebes under similar conditions. When closely pursued with a canoe 

 they will dive repeatedly and if escape seems impossible will endeavor 

 to hide in the vegetation at the edge of the water instead of flying. 

 I have never seen it attempt to fly. 



Family COLYMBID^E. 

 52. Colymbus dominicus brachypterus Chapman. 



Colymbus dominicus LlNN^US, Syst. Nat., I, 1766, 233. — Frantzius, Jour. fin- 

 On. 1869, 379 (Sarapiqui River). — Zeledon, An. Mus. Nac. de C. R., I, 

 1887, 133 (iNaranjo de Cartago). 



Podicipes dominicus Grant, Cat. Birds Brit. Mus., XXVI, 1898, 520 (Costa 

 Rica [Endres and J. Carmiol]). — Salvin and Godman, Biol. Centr.-Am., 

 Aves, III, 1904, 442 (Laguna de Ochomogo [Underwood in /?'//.]). 



Podily?nbus dominicus Lawrence, Ann. Lye. N. Y., XX, 1 868, 144 (Dota [F. 

 Carmiol] ). 



Colymbus dominicus brachypterus Chapman, Bull. Am. Mus. Nat. Hist., XII, 

 Art. XIX (critical). 



U. S. Nat. Museum : Laguna de Cartago; San Jose (Ridgway). 



Bangs Collection : Pozo Azul de Pirris, Tenorio (Underwood). 



C. H. Lankester Collection : Cariblanco de Sarapiqui. 



Fleming Collection : Azahar de Cartago (Underwood). 



Carnegie Museum : Bonilla (Laguna Chiquita) and Buenos Aires 



(Carriker). Six skins. 



A series of five males vary greatly in size, the wing ranging from 

 94 mm. to 104 mm. while the coloration is very different (probably 

 due to age). Three birds have the whole head and neck dark sooty, 

 two with a little sprinkling of white on the throat, while two others 

 have the whole chin and throat white, the dusky color being restricted 

 to a band across the upper chest. They average a little larger than 

 the measurements given by Mr. Chapman for brachypterus, byt are 

 nearer that than true dominicus. 



Ranges over the whole of Costa Rica, but prefers the more temperate 

 regions, that is, between 1,000 and 5,000 feet. They were very abun- 



