958 I. M. Hawiery 
the abdomen is pointed instead of rounded and the bristles on the body 
are fewer and shorter. The femaie lacks the prominent fringe of hairs found | 
on the tibia of the male, and is harder to distinguish from related species. 
In brassicae the pre-alar bristle is as strong and as long as the first 
dorso-central one, while in cilicrura and antiqua it is only about half as 
long. In antiqua there are two nearly equal setae on the anterior (outer) 
side of the middle tibia, while in c7licrura there is usually but one. The 
species antiqua is ordinarily larger than cilicrura. The length of the female 
of celicrura is 5 millimeters (4 inch). 
LIFE HISTORY AND HABITS 
The egg 
There is little in the literature regarding the egg-laying of Hylemyia 
cilicrura. Whelan (1916) reports that the fly usually places its eggs 
either on the stems of plants just as they come thru the soil, or on decaying | 
vegetable matter. Howitt (1911) states that the eggs are deposited on 
decaying matter in the soil. Lugger (1896) was able to bring about the 
deposition of eggs by flies in captivity, but he believed the eggs to be sterile 
for he failed in his attempts to rear flies from them. Chittenden (1909) 
mentions an instance in which decomposing crimson clover that had been 
plowed under attracted flies as a place for oviposition. 
Period of incubation 
In July, 1917, at Perry, New York, the length of the egg stage under 
very moist conditions was between 24 and 48 hours. Very few eggs were 
found and the exact time of oviposition was in doubt. 
In 1918 eleven first-brood eggs under observation hatched in an average 
of 66 hours, as shown in table 1. There was a wide variation, from 41 to 
91 hours, and many eggs, the exact hatching time of which could not be 
noted, hatched within these limits. Eggs were kept in petri dishes on 
moist blotting-paper or damp earth. 
TABLE 1. Leneru or tHe Hae Srace in 1918 
Number Time of ; : Length of stage 
of eggs deposition Time of hatching (hours) 
Dis eres May 23; 3\p.m....- May 27, 9.30, 10, 10, a.m...... 96.5, 91, 91 
A ere leave 20 apse May 27, 9, 10, 10, 11.30, a. m...| 41, 42, 42, 43.5 
4.........| May 25, 3 p.m.....) May 28, 9.30, 10, 10.30, 10.30, 
BONN ihe t as cae See (OYA, Al, Too Ales: 
Average, 66 hours. ; 
