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PROCEEDTNaS OF THE NATIONAL MUSEUM. 



VOL. 42. 



cent (less purplish) neck and sides of head; much lighter, more fulves- 

 cent jugulum, conspicuously contrasted with the surrounding parts; 

 and usually somewhat lighter posterior lower surface. Compared 

 with Butorides virescens dominicanus it has the neck and sides of head 

 darker, duller, and more rufescent; the jugulum much more fulves- 

 cent and conspicuously contrasted with surrounding parts; also the 

 lower posterior parts darker. It may be separated from Butorides 

 virescens cuhanus by its longer wing and tail; lighter, duller, more 

 rufescent (less purphsh) neck and sides of head; conspicuously 

 lighter, more fulvescent, and more contrasted jugulum. It is very 

 easily distinguished from Butorides virescens christophorensis, by 

 reason of its darker, duUer, much less fulvescent (more purplish) 

 neck and sides of head; much more contrasted jugulum; and much 

 darker posterior lower parts. It is much unhke Butorides virescens har- 

 hadensis inasmuch as it is larger, though with a relatively more slen- 

 der biU; and has the neck and sides of head duller, less fulvescent and 

 somewhat more purplish, particularly posteriorly; the jugulum much 

 more fulvescent and thus strongly contrasted with the surrounding 

 parts; and the posterior under parts darker. It is even more differ- 

 ent from Butorides virescens hahamensis in its much greater size 

 throughout, darker, duller, less fulvescent (more purplish) neck and 

 sides of head, and darker posterior lower surface. 



A single bird in juvenal plumage does not differ from the same 

 stage of Butorides virescens cuhanus. 



This island race is rather peculiar in its combination of color char- 

 acters; for the fulvescent cheeks and jugulum are in more decided 

 contrast to the adjacent parts than is the case in most of the other 

 forms of the species; and the hind neck is unusually duU colored. 

 The jugulum is still more fulvescent in two Field Museum specimens 

 (Nos. 33659 and 33662) than in the type. 



So far as known it is peculiar to the island of Tobago and perma- 

 nently resident there. 



Five specimens have been examined, all from the island of Tobago. 



Measurements of specimens of Butorides virescens tohagensis. 



1 Used in measurement averages on p. 571. 



2 Collected by W. W. Brown, on Tobago Island. 



3 Type, collected by R. W. Rawson, on Tobago Island. 



