0. G. Hewitt 
H53 
Birmingham where^ of 24,572 flies caught, 91 per cent, were ilf. domestica 
and 4’7 per cent. F. canicularis. From observations that I have made 
in many localities in different neighbourhoods, I do not think that this 
species would often form more than 25 per cent, of the total fly population. 
After M. domestica, however, it is the next fly of importance inhabiting 
houses and well deserves the title of Les.ser House-fly. It is known in 
Germany as “die kleine Stubenfliege.” The specific description of this 
species is as follows : 
Male. Head iridescent black, silvery white especially around the 
eyes. The antennae are blackish grey with a non-setose arista shown in 
the figure (Plate VII). Palps black. The thorax is blackish grey with 
three indistinct black longitudinal stripes; the scutellum is grey and 
bears long setae ; the sides of the thorax are lighter. The abdomen 
consists of five visible segments. In the male it is somewhat parallel¬ 
sided and possesses three and sometimes four pairs of golden translucent 
areas situated laterally in the proximal region. The legs are black and 
the middle femora bear comb-like setae below (Fig. 3). The somewhat 
large squamae at the bases of the wings are white and the halteres are 
yellow. Length 5‘5 mm. 
Female. The head of the female is grey with a wide frons, black 
frontal stripe and grey sides. The longitudinal stripes of the thorax 
are faint and the abdomen, which is more pyriform than that of the 
male, has a slightly golden attachment. 
Proportion of sexes. Great disparity in the proportion of males 
to females is found in this species as it occurs in houses. Hamer 
showed in 1909 that the males constitute from 75 to 85 per cent, of the 
total flies of this species caught in balloons and on fly papers. This, 
however, does not indicate a disparity in the proportion of males to 
females in the species, as I have found that the females are moi’e 
commonly found out-of-doors, especially in the neighbourhood of the 
breeding places. 
Breeding habits. The breeding habits of this species are somewhat 
similar to those of the House-fly, M. domestica. The larvae breed in 
decaying and fermenting vegetable and animal matter and also in excre- 
mentous matter. In 1848 Heeger recorded it as living in the caterpillars 
of Epischnia canella ; Roth found them in the nest of the humble bee, 
Bombus terrestris, and Schiner observed them in the bottom of a box in 
which a dormouse had been kept. Taschenberg also records the larvae 
as being found in snails, in old cheese and in pigeon nests; he reared 
11—2 
V 
