INSECTS AND OTHER ANIMAL Pests INJuURIOUS TO FIELD Beans 965 
up a drop of moisture as they find it. When the flies are moving about in this 
manner, the wings are overlapped on the back and are thus out of the way. 
Twelve flies have been counted in three feet of furrow, and forty-two were 
seen in a square yard. A count of the flies taken on new soil on May 27, 
1918, showed fourteen mature females and one male. At this period or a 
little later, many flies may be taken by sweeping along the edges of fields 
and roadways. On June 18, 1918, many were caught in the tall grass at 
the edge of a field, a count showing about four males to every female. On 
July 8 there were forty-one males in a lot of forty-five flies taken by a 
roadside. It is apparent, then, that while the females are searching for 
places suitable for oviposition, the males may be found sunning themselves 
in grassy and weedy places. On sunny days, adults have been seen resting 
on mustard; and in the evening they are found on onion tops, kale, potato 
vines, daisy, and ragweed, and more rarely on other plants. Flies have 
also been observed hovering about a dead earthworm lying on the surface 
of the ground. 
On warm days, or during the hotter part of the day, the flies are very 
active, crawling restlessly near the top of breeding cages; but in cold 
weather they move slowly over the dirt on the floor of the cage, or remain 
quiet in the cracks of the soil. 
Tt was observed in the spring of 1919 that flies might be taken in the grass | 
along roadsides, and in wheat and oat fields, before they made their 
appearance around plowed ground. It would seem, then, that as the 
egg-laying period approaches, flies have a tendency to come into the open 
and seek loose, moist soil. This is especially true if such soil contains, as 
an additional attraction, the decomposing roots of clover or quack grass. 
HIBERNATION 
The writer has little data on the hibernation of Hylemyia cilicrura. 
Cages have been placed in fields and meadows early in the spring, but no 
flies have emerged in them. LEarly in May a few flies with ovaries partly 
mature have been found. It is probable that these were early specimens 
of the subsequent first brood, which had wintered in puparia; but they 
may have been flies that had emerged late in the previous summer and 
had hibernated as adults. It has not been possible to keep flies that are 
taken in late summer, alive in cages thru the winter. The writer believes 
that the insects more commonly pass the winter hibernating as second-gen- 
eration pupae, and emerge as flies from May 15 to June 1 of the next year. 
Such flies, taken in late May, had only partially developed ovaries and were 
fresh-looking specimens. In support of this pupal-hibernation theory, N. F. 
Howard? found czlicrwra hibernating in the pupal stage in onions in Wis- 
consin, and Dickerson (1910) showed that from pupae of czlicrura placed in 
cages in November, flies would emerge early in May of the next year. 
4 As stated in a general discussion reported in the Journal of Economic Entomology. vol. 9, p. 133, 1916. 
