THE CANADIAN ENTOMOLOGIST. 



421 



of the marginal stripe; legs pale. Length, 1.3 mm.; width, i.o mm. 

 Arizona (Nogales), Nimenmacher. 



Allied to vittigera but smoother, more broadly oblong and differing 

 in colour. The prothorax is but little narrower than the elytra and two 

 and one-half times as wide as its greatest length. The species from El 

 Paso, which I identified as trimaculatiis^ Linn. (Rev., p. 130), is as follows : 



H. oblongits, n. sp. — ( = trimaadati(s^ Csy., nee Linn.). — Differs greatly 

 from vittigera, Lee, in the ornamentation of the male pronotum, wliich is 

 said to be yellow, with a large basal black spot anteriorly lobed and 

 extending beyond the middle in that species, according to Crotch (Rev., 

 p. 232). It occurs in Missouri. 



A REMARKABLE CECIDOMYIID FLY. 



BY T. D. A. LOCKERELL, BOULDER, COLORADO. 



On Sei)t. 24, 1908, as I was walking down Seventeenth St , Boulder, 

 Colorado, I noticed a very singular fly upon the pavement. At first sight 

 I thought it might be a small Bibionid of some sort, but w'hen I had it in 

 the bottle, I was delighted to find that it was a most peculiar Cecidomyiid. 

 It is one of the Hormomyia group, the first to be recorded from the West. 

 I describe it as a Hormomyia, though its peculiar characters may eventu- 

 ally entitle it to a separate generic name. 



Hormomyia colorade/isis, n. sp, 

 ^ . — Length, 5^ mm.; wings almost 6 ; thorax blood-red, so arched 

 over head that the latter is quite invisible from above, and only the eyes 

 can be seen from an angle of about 45° in front ; dorsum of thorax with 

 short scanty black hair ; head pale ; antennae dark, at first sight appearing 

 26-jointed, but really 14 jointed, the joints after the first two being divided 



into a basal swelling and an apical 

 double swelling, each of the three 

 swellings (counting the apical as 

 two) ornamented with small white 

 loops, while the lowest and highest 

 each emit many long black bristles ; 

 all this being exactly as Xylodiplosis 

 prcecox (Bull. Soc. Ent., France, 

 1895, p. cxii), except that the long 

 bristles are much longer, being 

 much more than twice the length of the loops ; wings strongly dusky, with 

 much dark hair and a conspicuous dark fringe ; legs very thick, almost 



November, 1908 





F[G. 19. — Base oF wingf and male antennal 

 joints of Hormomj'ia. 



