442 
Anthomyides a larves carnivores 
middle) and two similarly placed posterodorsal bristles of which the 
lower one is sometimes missing. Wings with both cross-veins clouded ; 
outer cross-vein sinuous; cubital and discal veins widely diverging at 
tip. Squamae whitish, thoracal pair elongate. Halteres grevish- 
black with reddish-yellow base to stem. 
$. Very similar to the male. Frons very broad, the frontal stripe 
dusted greyish as in the male when viewed from in front or above, but 
appearing darker viewed from behind; the short fine hairs outside the 
frontal bristles are more numerous than in laeta and instead of the 
single pair of fine “ Kreuzborsten ” on the frontal stripe, these fine hairs 
spread across the stripe from the rows of frontal bristles to the usual 
position of the “Kreuzborsten.” Presutural dorsocentral bristles 
weaker than in the male and the rows rather wider apart. Abdomen 
very much as in laeta. Legs as in the male but no anteroventral spines 
beneath anterior femora towards tip; sometimes three bristles behind 
middle tibiae, and 1-3 anteroventral bristles to hind tibiae. 
Length 8-10 mm. 
The arrangement of the posterodorsal bristles on hind tibiae is 
very distinctive, all the other species having only a single posterodorsal 
bristle (the “eperon” or “soie posticale” of Schnabl). P. Goberti 
may be distinguished by the presence of three distinct pairs of well 
separated presutural acrostichals, and by its unclouded cross-veins; 
other allied species have a distinct posterodorsal bristle on front tibiae. 
The species is named in honour of Mr D. Keilin whose researches 
in the life-history of this and other species of Diptera have been the means 
of greatly increasing our knowledge of this much neglected subject. 
In addition to a male bred by Mr Keilin I have examined a pair 
in the Cambridge Zoological Museum Collection, the male taken “at 
squash in elm,” Cambridge, 4. viii. 1904, by Mr F. Jenkinson, the female 
in the New Forest, Hampshire, vi. 1904, by Dr D. Sharp. In my own 
Collection there is a very immature male bred by Mr H. Donisthorpe 
from pupa found in the New Forest in 1905, and a female which 
I bred out of material collected from an ulcerous wound in an elm tree 
at Chippenham, Cambs., in 1908. 
