556 [December 



iag spring, aiFord some pretty good characters. Although there is 

 nearly as much room for a long cocoon in the gall *S'. hrassivoides as in 

 the gall S. strobiloides, yet in the former the cocoon invariably envelops 

 the larva so tightly that it is difficult to be detached, and in the latter 

 it is invariably about long enough to hold three larvae packed length- 

 ways, the larva of this and other allied species being always found 

 lying in the basal end of the cocoon with its head towards the empty 

 tip. 5th. As already stated, the coloration of the imago varies asto- 

 nishingly, not only in the dried, but also in the living specimen, as will 

 be shown in detail in the case of almost every species where I have ob- 

 tained the imago. In the case of the abdomen 9 , the more or less 

 deep sanguineous color is due to the color of the included egrirs showino- 

 more or less through the more or less transparent integument, as is also 

 the egg-yellow color in the abdomen of many 9 Ephemerina. (See my 

 Paper Froc. Ac. iVat. Sc. Phil., Sep. 1862, pp. 374, 375, 377.) When 

 these eggs are partially extruded, it will be seen that in the inquilinous 

 Cec. alhovittata n. sp. the abdomen, instead of fulvous or sanguineous, 

 becomes in the empty part luteous like the abdomen of the S . A precisely 

 similar thing occurs in the abdomen of many 9 Ephemerina. (Ibid.) 

 In a few 9 Cecidom^ia, when dried — and I have noticed the same thing 

 in many living 9 9 — several eggs remain still attached to the oviduct, 

 and I suspect that the " two small oval lamels," stated by Winnertz to 

 be attached to the oviduct of the J^uropean C. {diphsis) pin! DeG., 

 are nothing but two eggs thus protruding. {Dipt. N. A. pp. 177-8.) 

 On the other hand the color of the hairs of the thorax, but nut of the 

 abdomen I find to be a constant character both in the living; and the 

 dried specimen, and to diifer in some species; and the same is true of 

 the arrangement of the hairs on the thorax, whether in rows or irregu- 

 larly scattered. As regards other structural characters, the length of 

 the oviduct varies greatly, according to the degree in which it is re- 

 tracted, as has been observed by Say, (Sai/'s Works, II. p. 5,) but the 

 average length differs considerably in some few species. The number 

 of joints in the % antenna varies by 2, or 3, or perhaps even 4 joints in 

 the same species, according to the general rule in Natural History, that 

 multiple parts, like the vertebrae of a snake and the stamens of polyan- 

 drous flowers, are inconstant in number.* Specimens not uufrequently 



*Most Coleoptera have 11-jointecl antennae, and the number of joints is inva- 



