is broad, and subtransverse in direction) is narrower and saliently angulate, with the 

 point just in front of the interruption ; the dark apical region extends to the ex- 

 tremity of the wing's disc, and its inner margin is slightly concave or subtruncate. 

 The dark hairs by the forks in the fascia first referred to hardly constitute black 

 spots. Costal fringe impure whitish from the base to nearly opposite the bifurca- 

 tion of the radius in the ? , but scarcely so far in the ^ ; also whitish, at least in its 

 upper layers, at, and for a short distance on both sides of the end of the subcosta ; 

 and again, in the $ , by the end of the anterior radius the dark fringe is often 

 overlain by some whitish hairs spreading outwards. At the posterior margin of the 

 wing, small outward spreading tufts of the same whitish hair are arranged inteinor 

 to the fringe at the ends of the anal, postical, and posterior pobrachial nervures ; 

 and sometimes in transmitted light the dark hair-streak at the ending of the postical 

 nervure appears in consequence to be almost isolated. 



In the foregoing citation of Meigen, Sjst. Beschr., Bd. i, tab. iii, 

 18 (1851), its assignment to Ps. palustris in the desci'iptive text, 

 op. cit.., p. 83, is treated as a lapsus calami on Meigen's part, on the 

 supposition that the figure is a reproduction of the one published in 

 1804 of P. trifasciata. Comparison of good specimens of both these 

 species with the descriptions and the figure in question, supports this 

 correction —making some allowance for the artist. Zetterstedt's 

 mention of the apical fascia, op. cit., 3074, " iiitus fere truncata,'^ 

 designates the present species ; and the number of blackish joints in 

 the tarsi of Haliday's var., dealhata, governs its synonymy. 



The locality whence Haliday's var. y, deaurata (loc. cit.) was 

 obtained is suggestive of its being possibly P. exquisita ; but " flavido- 

 hirta " seems too bright a colour for this species, and besides that, the 

 white fasciae in its wings do not enter the fringes. 



15. Pericoma pulchra, Etn. 

 P. trifasciata, Hal. MS., Walk , Ins. Brit. Dipt., iii, 259 (1856), 

 excluding vars. — P. pulclira, Etn., ante, 2nd ser., vol. iv, 123, and vol. 

 V, pi. ii, P. 15a (detail). 



Within the region of bristling hair, the dark fascia across the bases of the forks 

 is saliently angulate and cuspidate at the praebrachial nervure, and its cusp is almost 

 or quite cut ofE from the dark apical region by the outer zigzag fascia of whitish 

 bristling hairs and some outward spreading whitish hairs thei'ewith associated, their 

 connection (if maintained) being only established by a few oblique dark hairs pos- 

 terior to the point of the cusp that just meet the edge of that region 6n the anterior 

 pobrachial nervure. The same dark fascia, of moderate width from the costa to the 

 cubitus, and narrow from tlie praebrachial to the postical nervure, expands posteriorly 

 to attain its greatest width in the posterior fringe ; the hairs in proximity to the 

 forks are not darker than the remainder. The dark apical region extends to the 

 extremity of the wing's disc, and its inner margin is sharply indented between the 

 cubitus and the pra;brachial nervure ; within it all the hairs at the endings of the 



