—50 [November, 



Anteunce grey-liaired ; the verticils of hairs not compressed ; scales present only on 

 the scape, and a very few on the 3rd joint. 



By assuming that Meigen and Zetterstedt described this species 

 from the female (since no mention is made by them of the frontal 

 tuft of the male) it is allowable to follow subsequent authors in 

 attributing the name nuhila to the present insect instead of to the 

 next species. The females of nuhila and triviaJis are indeed so much 

 alike that it is hardly possible to be sure of the specific authenticity 

 of specimens of this sex of either, should the locality of their capture 

 be frequented by males of both species. Where males are concerned, 

 even though the notum be denuded in extreme old age, P. nuhila can 

 nearly always be distinguished from P. trivialis by the marked 

 difference in the frontal hair. 



Attention has already been directed to the frequent confusion of 

 this species with Ulomyia fuliginonn by Dipterologists. An admixture 

 of both of them with some of P. notabilis is occasionally labelled 

 P. palustris. As an extreme illustration of what frequently takes 

 place to a smaller extent in cabinets, one collection may be referred 

 to, wherein eighteen specimens of P. nuhila are distributed among six 

 differently named " species," three of which are consecutive. The key 

 to many obscure pre-8chinerian " species " of Psycliodidee figures often 

 enough in modern museums. 



7. Pericoma tkitialis, Etn. 

 P. trivialis, ante, 2nd ser., vol. iv, p. 121, and vol. v, pi. i, P. 7, 

 a, b, d (details). 



Antennae of $ conformable to those of P. ntibila, ^ , and with the verticils of 

 hair less decidedly compressed than in the J of that species ; the scales on the scape 

 and the few elongate scales among the hairs of the next joint, glossy pale yellowish ; 

 the longer hairs on the ilagellum black, and the shorter glossed with light greyish 

 or whitish on change of posture. Palpi fuligineous, glossed with whitish or silvery- 

 grey. Occiput with short appressed black hair. Pubescence on the mesonotum 

 " shot " at the tips of the hairs with greyish-black ; that on the metanotum either 

 (like the preceding) yellowish-brown or blackish-brown, contrasting in some postures 

 with the erect brownish-yellow hair of the 1st abdominal segment and fringes of the 

 alulse ; but on change of posture these also shift to brownish-black. 



In immature $ specimens the pubescence on the notum posterior to the light 

 yellow patch on the pronotum is of a very dark brown tint, " shot " at the tips of 

 the hairs with blackish ; in aged specimens the light yellow patch alluded to becomes 

 brownish, like the remainder. 



Abundant in the south of England, and collected in Scotland by 

 Mr. King at Loch Lomond (1 ? ), and Loch Maree (5 c^*, 9 ? ). 



(To he continued ) . 



