18S3.] 83 



Pieris napi being a common English insect, I would suggest the experiment of 

 breeding it in a hothouse for several generations, in order to ascertain if it is as sus- 

 ceptible to temperature variations under artificial, as it is in Japan under natural 

 conditions ; and in order to show that the experiment is worth a trial, I enclose 

 the wings of two ? , one taken in Alarch and the other in June. — H. Petee, 

 Yokohama : June 4th, 1883. 



Stridulation of Arctia caja. — Notwithstanding the stray notices scattered 

 over entomological litei-ature, I have been very reluctant to believe in the stridula- 

 tion of this moth. At the outset, led to look for some startling musical 

 apparatus, it was not until I began to ijerceive that a majority of butterflies produce 

 distinguishable sounds by means of delicate and minute vein-striae, that I found it 

 possible to entertain the idea ; a matter rendered the more difficult, because the 

 auditory cells in this species are so poorly developed that it was difficult to believe 

 that the stridulation, if a fact, played any part in the insect-economy. The late 

 Prof Zeller remarked (" Isis," 1840, p. 228), " I have observed how one of my three 

 newly-emerged female Euprepia caja, when roused up and provoked a bit, so that it 

 was forced to crawl backwards, made an audible crackling noise. The experiment I 

 often repeated for several days. Also, when I held its abdomen fast between my fingers, 

 there was a crackling when it beat its wings." Pursuing the train of thought sug- 

 gested by the vesicular organ in the allied pudica, he subsequently adds (Stett. ent. 

 Zeit., 1867, p. 41) : " I remark in a male Caja an oblique smooth place, almost 

 longish-quadrangular, with a perpendicular depression in the centre that might well 

 serve the same end as in the species of the Lithosiidce ;" the allusion being probably 

 to the episternum of the meta-thorax. 



A few days ago, I was enabled to renew Prof Zeller's experience with a crippled 

 female of caja that made a great rustling and crackling by jerking its crumpled 

 wings up and down, when disturbed during the deposition of unfertilized ova. 

 After a painstaking investigation of the matter, I myself came to the conclusion that 

 the crackle was owing to the friction of the callosity at the base of the fore-wing on 

 the edge of the hind-wing. (Fn the instance before me, a notch in the callosity caught 

 the angle of the hinder-wing near the spurs.) I also noticed that the male caja 

 links its wings for flight by passing a stout spine over a tuft of hair on the edge of 

 the sub-costal vein of the fore-wing, which is confined by reason of an oblong lappet 

 of hair falling down from the inner costal vein ; but that the female, with less capa- 

 bility of aerial locomotion, has four lax bristles, replacing this single spine, which 

 also catch in the tuft of hair, but then there is no little lappet to confine them in 

 their place, as there is in the male. Consequently, by this adaptation, the female 

 has a greater power of moving the wings independently of each other, than the male ; 

 and, therefore, I presume the female may have a greater facility for crackling. — 

 A. H. SwiNTON, Guildford : July Idth, 1883. 



Qrapholitha ccBcana, Scliliiger (coecana, II. -S.), a Tortrix new to Sritain. — Head 

 pale brownish-grey. Eyes black. Face and palpi pale ochreous-grey. Apical joint of 

 palpi slender, nearly as long as the basal, which is stout and curved upwards ; 

 middle joint ascending, curved, more than twice as long as the apical, and as stout 



