"*-^" [November 



racters of the % 9 imago remaining identical. — C^nips q. spongifica 

 0. S. and C. q. inanis 0. S. 



7th. Difference of food is accompanied by a slight, but constant 

 change in the coloration of the abrlomen of the % 9 imago, and by a 

 very slight change in the chemical properties of the gall-producing 

 secretions, the galls of the two insects, though typically somewhat dis- 

 tinct, being connected by intermediate grades in the case of the latter. — 

 Ci/nips q. punctata Bassett and C. q. podagrse. Walsh. 



8th. Difference of food is accompanied by one marked and perfectly 

 constant colorational difference, and others which are not perfectly con- 

 stant, in the larva, but none whatever in the % $ imago. — HaUsidota 

 tessellaris Sm. Abb. and H. Antiphola Walsh. 



9th. Difference of food is accompanied by several slight but constant 

 structural differences in the % imago, but none whatever in the 9 

 imago. — Cfj/fus rohinise Forst. and CI. p ictus Drury. 



10th. Difference of food is accompanied by a slight but constant 

 structural difference in both % and 9 imago. — 1. Tingis tiUse n. sp. 

 and T. amorphse n. sp. 2. (Doubtful.) Diapheromera femorata Say 

 and D. Vein. n. sp. 



11. (Doubtful.) Difference of food is accompanied by very strong- 

 structural and colorational differences in the larva and in all probability 

 by a constant structural difference of generic value in the 9 imago, the 

 S imagos being to all external appearances identical, and the two in- 

 sects belonging to different genera. — Sphingkampa distigma % 9 

 Walsh and Dri/ocampa hicolor % Harris. 



12th. Difference of food is accompanied by marked and constant dif- 

 ferences, either colorational, or structural, or both, in the larva, pupa 

 and imago states. — Halesidota tessellaris Sm. Abb. and //. caryse Har- 

 ris, and hundreds of species belonging to the same genus and com- 

 monly considered as distinct species. 



The constitution of the human mind is such, that the same evidence 

 carries with it very different degrees of weight, when presented to dif- 

 ferent intellects. Others will no doubt draw different conclusions from 

 the facts catalogued above ; but for my own part, as on the most care- 

 ful consideration I am unable to draw any definite line in the above 

 series, and to say with certainty that here end the Varieties and here 



