June, 1903.] BuscK : The Codling Moth. 107 



Denis = cana ?Ia\vorth) . All three species are genetically distinct 

 and Hiibner did not indicate which was the type ; this consequently 

 must be determined by elimination. 



In 1829 Treitschke erected the genus Carpocapsa (Treitschke 

 Schmett. Eur., VII, p. 231) and on the next page of the same work his 

 genus Grapholita appeared ; the first of these genera contained pomo- 

 nella Linn, and four other species, the latter contained //f//^//7i/ar//«'rt'//t?, 

 Schiff. and Den., aspidiscana. Hiibn. and eight others. No type was 

 indicated for either genus. 



From these facts Lord Walsingham concluded (Proc. Zool. Soc. 

 Lond., 1897, p. 130) that one or another of Treitschke's two genera 

 must fall as synonyms with Cydia of Hiibner and making use of a sub- 

 sequent work by Stephens (111. Brit. Ent., Haust., IV, p. 119, 1834) 

 he determined that Carpocapsa^\vo\A^{zS\, while if his premises — that 

 one of the two genera must fall — had been right, Grapholita should 

 logically fall as pointed out by Prof. Cockerell and Carpocapsa be 

 retained as the first restriction of Cydia on account of its page prec- 

 edence. 



As, however, a genus is not fixed before its type is determined and 

 as both Carpocapsa and Grapholita of Treitschke contained several 

 other species besides the three in Hiibner's Cydia none of them is 

 necessarily synonymous with this genus ; in fact none of them could 

 rightfully be made suclv according to the rules of nomenclature unless 

 all the species contained in them were truly congeneric, which is not 

 the case. 



But the type of Carpocapsa had already been fixed as pomonella 

 before the above-mentioned work of Stephens, by Curtis (Brit. 

 Entom., VIII, p. 352, 1831), and that species could therefore not 

 rightfully subsequently be fixed as the type of Cydia, which must be 

 one of the remaining species of that genus. 



Besides Curtis' work another earlier reference bearing on the sub- 

 ject is found, namely Kirby's and Spence's Introduction to Entomology 

 in which in Vol. Ill, p. 123, 1S26, pomoneiia Linn, is given the gen- 

 eric name Erminea. 



This being the earliest elimination from Cydia it would have held 

 good for potnonclla, which as the only species mentioned must be re- 

 garded as the type of the genus, if the name Erminea had not previously 

 been used in another sense by Haworth.* 



* That such is the case I did not realize before Professor Fernald called my atten- 

 tion to it. 



