iflia.] 95 



P. bergenstammi, Mil\, and domedica, Wood. lu tlie January num- 

 ber of "The Annals of Scottish Natural History" for 1910, Mr. Malloch 

 has shown that these two insects are the sexes of one and the same 

 species, on the strength of a mated pair talcen by Mr. Jenkinson at 

 Cambridge. Of this pair the female has four dorso-central bristles and 

 the male only two, which was the character that led me to treat 

 them as distinct species. All the so-called domestica I have taken 

 have been males, and have had but one pair of these bristles, whilst 

 my only bergenstammi is a female and has two pairs. This female 

 was swept at Stoke Wood ; the males, some 20 in number, have in- 

 variably been boxed off the window of the house ; and, strange to say, 

 frequent sweeping outside in the garden has been an utter failure, 

 neither male nor female having come to hand by this means. 



Perhaps one ovight not to be greatly surprised at this difference in 

 the chaetotaxy of the sexes. A very similar condition of things occurs 

 in more than one of the species with four Ijristles to the scutellum in 

 the genus Apliiocheeta, Brues (the G-roup II of Becker). For whilst in 

 the female all four bristles are strong and well developed, in the male 

 the anterior pair are weak, and may even be little better than mere 

 hairs ; the stronger annature being here as in the other case in favour 

 of the female. 



Hypncera irregidaris, sp. n. Closely allied to femorata, Mg., but 

 differing in several important particulars. Described from a single 

 specimen : — 



S ■ A deep black insect with nearly colourless wings : Thorax somewhat 

 shining; frons black with a moderate gloss, nearly i broader than long, the 

 bristles strong (the middle row straight, the lower slightly curved forwards) ; 

 palpi black and of ordinary form and armature ; wings (fig. 1) faintly tinged 



with yellowish brown, costa to 

 middle of wing, fringe short, 2nd 

 thick vein forked, f virnished as far 

 as the fork with niunerous small 

 and delicate bristles or hairs as in 

 femorata and beyond that gradu- 

 Fig. 1. Hypocera irregularis, <J X 18. ally dilated, inner branch of fork 



extremely slender, threadlike and finer even than one of the thin veins, 1 equal 

 to 2 + 3, 1st thin vein deeply curved at its original point from the fork ; legs 

 stout and black, tarsi and forelegs more yellowish, fore tarsi stout, tibial spines 

 strong, one on the front tibiae, two close together in upper third of middle pair, 

 and two on the outer or anterior side of the hind pair, namely, one at about the 

 basal third and the other close to the apex ; abdomen quite dull, 2nd segment 

 nearly twice as long as the 3rd, the 6th barely longer tlian the 5th, hypopy- 

 gium much as in femorata, and the anal organ not prolonged externally as in 

 that species. 2 J mm. 



