happens that the first and last species are as nearly related to 

 other genera, as to that in which they are included; and 

 although this is frequently a proof of the natural arrangement 

 of the subjects, there are those who, considering it a defect, 

 have adopted the pernicious practice of giving every thing a 

 generic name which does not strictly accord with the type : 

 as, however, it is the union, not the separation of groups that 

 is so desirable, it becomes the duty of every one to dispute 

 such innovations ; since nothing is so likely to retard, if not to 

 overthrow science, as encumbering it with unnecessary names. 

 In the Catalogue I am now publishing, some of these subge- 

 nera have been registered, but they will not form any part of 

 the present work. 



In the genus Glaea, the strongly depressed bodies with re- 

 flexed sides present a character that marks all the species 

 excepting G. rubricosa, which has the antennae also more hairy 

 beneath ; and the caterpillar of G. rubiginea is hairy like some 

 of the Bombycidae, whilst in all the others I believe they are 

 quite naked. 



The British species are 



1. G. rubricosa Hub. Och. — mista Hilb. — rufa Haw. E?iL 



Trans, tab. 5.f. 1. — End of March; banks of net- 

 tles. 



2. rubiijrinea Hilb. Haw. 



3. Yaccmii Li?in. Haw. Goda. — m. Sept. skirts of woods. 



4. spadicea Hub. Haw. ditto ditto. 

 . 5. polita Hub. Haw. ditto ditto. 



6. subnigra Haw. — Curtis Brit. Ent. pi. 268. 



7. satellitia Linn. — Don. 5. 168. — e. Sept. skirts of 



woods. 

 The plant is Orchis {Gymnadenia Brown) conopsca (Red- 

 handed Orchis). Communicated by Professor Henslow. 



