ENTOMOLOGY 116 



Mr. Doubleday says, "though closely allied, they are readily distinguished; 

 the central black spot in the superior wing of Fluviala is destitute of the 

 white iris, and there is a short oblique line at the apex of the wing, which 

 is wanting in Gemmata," AVe hope collectors will look out for these species 

 next summer. — Ed. 



Lasiocampa quercus var. callunce. — I do not think from all that has been 

 written about our Scotch L. quercus, that it can be considered specifically 

 distinct from the English. In a species I look for characters in the perfect 

 state, which shall separate it from every other species. These characters, in 

 L. callunce (so called) I have not been able to see. You can convert Mr. 

 Crewe, however, by assuring him, that in Scotland, "from a batch of eggs 

 laid by a § L. callunce" all the larva; have blue rings when young, and all 

 of them remain about ten months and a half in the pupa state. Mr. Crewe 

 would like them to lie twelve or thirteen months in their cocoons, but I 

 think he should not insist upon this, and, to be reasonable, should be satisfied 

 with ten months and a half. Perhaps, however, Mr. Crewe's conditions are 

 limited to England. The middle of August is the average time at which 

 they spin their cocoons, the range being from July to the first week in 

 September. The imago may be considered to appear on the 1st. of July, 

 thus giving ten months and a half for the pupa state. This species being 

 in this latitude so strictly biennial,* it follows that imagines of 1857 are not 

 related in blood to their cousins (?) of 1856. I do not know whether this 

 has been remarked before. In relation to this particular, I have observed 

 that the perfect insects are more abundant every second year: 1855 and 

 1857 were plentiful years. — A. Chapman, Bothwell Street, Glasgow, March 

 20th., 1858. 



Half-broodedness v. Double-broodedness. — I have had two pupa) of N. 

 Dromedarius, and five of N. Camelina two winters. They changed to pupse 

 in September, 1856. — Idem. 



M. Guenee's change of names of the Geometrce. — We have received a letter 

 from our friend Mr. Doubleday, in which that gentleman explains that we 

 were in error when we stated that his Catalogue was formed on the basis 

 of Guenee's nomenclature. We have much pleasure in making the following 

 extract from Mr. Doubleday's letter: — "I have just seen 'The Naturalist' 

 for April, and wish to correct a little error into which you have fallen, with 

 regard to my list of insects. Guenee had nothing whatever to do with the 

 arrangement or nomenclature of the Geometrce. When I undertook that 

 Catalogue, I had no acquaintance with M. Guenee. * * * I subsequently sup- 

 plied him with the names attached by Linnseus himself, in the Linnean 

 cabinet to the Tortrices. * * * M. Guenee has endeavoured in all his works, 

 to restore the Linnean names where no doubt existed about them, and there 

 can be no pretension for again changing these names." With reference to the 

 species and varieties, Mr. Doubleday remarks, — "I have always thought Fer- 



* I met with an exception once : one passed two winters as a pupa, thus making its dura- 

 tion of life three years. 



