December, 1906.] 265 



exception of one of my females, the others fully confirm Mr. Collin's 

 observation {vide p. 179) on the usual absence of the bristle from the 

 hind tibiae of this species. This female is further exceptional in that 

 the front pair of scutellar bristles are distinctly weaker than the hind 

 pair. The peculiar pair of forceps-like organs beneath the hypo- 

 pygium are highly characteristic, and unquestionably a:fford the 

 readiest means of identifying the male ; and it would be better, when 

 drawing up the table, had I selected it as the leading characteristic 

 in place of the one used. 



As regards the three new species. Both sexes of vitrea, two of 

 each, have been taken. It comes near perennis, but the differences 

 in the venation, in the characters of the genitalia of both sexes, and 

 in the colour of the halteres, leave no doubt whatever that it is per- 

 fectly distinct. It is also a distinctly smaller insect. Only the 

 female of luteifeonorata has so far turned up. Two have been taken 

 here, namely. Stoke Wood 30.9.03 and Black Mountains i0.8.04,and one 

 by Dr. Sharp in the New Forest in October, 1908. The New Forest 

 insect has the thorax suffused with reddish, no trace of which is notice- 

 able in the Herefordshire examples. Suhluguhris is perhaps more like 

 vitrea than Juguhris wdth which it is compared in the table, but its 

 stoutly built (normal) legs cannot possibly be mistaken for the long, 

 slender limbs of vifrea. Both sexes have been obtained ; a female 

 by Dr. Sharp in the New Forest October, 1903, and two males by 

 myself indoors 11.10.04 and 4.10.05. 



The affinities of unispinosa, nudipalpis, and autumnalis with the 

 3-veined section seem to be indicated by the general weakness of the 

 tibial armatures and by the very long and slender legs of autumnalis. 

 Of the last mentioned I have seen only two males, kindly lent by 

 Mr. Verrall, and with the records, Newmarket 31.1.93 and Cambridge 

 13.1.04. 



Abroad they meet with two forms of the male of abdominalis : 

 one, the type, with a yellow abdomen like that of the female, the 

 other, a variety, with a black abdomen. Here we seem to have only 

 the variety. Ahbreviata is closely related to it, and is found at Cam- 

 bridge ; a female taken by Mr. Jenkinson in his garden and kindly 

 given me by Dr. Sharp bears the date 20.8.02. 



Dorsalis and hergenstammi are both very rare. Of the former 

 I took a pair in cop. at Woolhope 28.5.98, and of the latter a female 

 28.7.05 in Stoke Wood. The end of the abdomen is rather curiously 

 truncated in the females of these two species, making it at first sight 

 hard to say, without the other sex at hand for comparison, whether 



