on the Genus Coereba. 5.25 



never met witli one, and the only authentic specimen that 

 he knew of was shot in the spring of 1904 by Mr. Charles 

 Vernet of St. George's. 



CffiREBA ATRATA. 



Certhiola atrala Lawrence, Ann. N.Y. Acad. Sci. i. no. 5, 

 1878, p. 150 (St. Vinceut). 



Coereba atruta Ridgw. Birds N. & M. Amer. pt. ii. 1902, 

 p. 422. 



Ccpreba atrata (Black form) Austin Clarke, Auk, xxii. 

 p. 393. 



Hub. Island of St. Vincent, Lesser Antilles. 



Measurements. Wings ot! 12 S S average 61-63 mm. 

 (one 65 mm.). Bills average larger than in C. wellsi. 



16 c? c? & ? ? . Coll. Brit. Mas. 



6 c? c? &2 ? ?. Coll. P. R.L. 



Quite a common bird on St. Vincent. This and the next 

 three species are melanistic phases of the normally coloured 

 types of the genus. The explanation of their occurrence in 

 such dominating numbers on all the four islands on which 

 they have now been found to flourish is a problem of genetics 

 of extreme interest. Whether these melanistic phases have 

 arisen in quite recent times there seems to be no evidence 

 to shew, but that they are dominant races is evident. 

 According to Ober, the normally coloured form was once 

 met with on St. Vincent in sufficient numbers to be 

 noticeable. 



There is no evidence whatever to enable us to say how 

 long the black phases have inhabited the Los Testigos or 

 the Los Roques groups of islands (see below) ; but bearing 

 in mind the very recent origin of melanistic phases of 

 British moths, noticeably in the case oi Amp Jiidasj/s betularia 

 since 1850 (see L. Doncaster, 'The Entomologist's Record,' 

 vol. xviii. no. 7), it is impossible to refrain from speculation 

 as to whether these black forms of Coereba have not come 

 into existence in similarly recent times. Against this 

 supposition is the fact that no intermediate forms have 

 been met with, so far as I am aware. Moreover, on the two 



