10 BULLETIN 1359, U. S. DEPARTMENT OF AGRICULTURE 
tion of weevils present among the beetles was very large, as members 
of this group were identified 27 times. Many were small forms 
found on aquatic vegetation. Other groups of beetles are repre- 
sented by scattering individuals picked up at random from the mud 
or the scanty growths of grass in marshy lowlands. Many of these 
miscellaneous beetles probably represent individuals which had 
drifted in oil the shore after having been drowned. A few are forms 
found about decaying bodies, objects encountered frequently on 
borders of pools where the Wilson phalarope makes its home. Rove 
beetles (Staphylinidae) and shining carrion-beetles (Histeridae) 
belong especially in this class. 
Diptera. — Flies are one of the main sources of food supply for the 
Wilson phalarope, constituting 43.1 per cent of the total. Mosquito 
larvae which alone amounted to 5 per cent of the whole, constituted 
one-tenth of the food in 27 stomachs collected in May; in 45 taken 
in June they composed 2.5 per cent. These larvae were taken also in 
numbers in birds killed in August. That large numbers of larvae 
were often consumed at a single meal was shown by the presence of 
many of the breathing tubes through which the wrigglers obtain air 
when at the surface of the water. Crane flies (Tipulidae) were found 
10 times, their larvae, which are aquatic, 8 times, and adults twice. 
Gnats ( Chironomidae) were more abundant in the food, being identi- 
fied in 20 stomachs, the larvae and pupa3 in 10, and adult flies in a 
like number. In the immature stages insects of this group live in 
water, but the adults frequently swarm over marshes. To birds 
secured in the Great Basin region alkali flies (Ephydridae) were favor- 
ite food. In all, members of this family were found 23 times, mostly 
in the larval or pupal stages, when they are easily accessible. The 
-abundance of these insects in many localities is almost beyond ex- 
pression in words, and they form a prime source of food in saline 
situations where few other creatures can exist. Other aquatic fly 
larvae that occur in fresh water were taken, among them a large 
.horsefly (Tabanus). 
Miscellaneous.— Snails were found in two stomachs taken in March, 
but amounted to only 0.3 per cent of the diet for the whole period. 
Other miscellaneous animal food came to 1.8 per cent, including a few 
larvae of Mayflies and in one case the immature form of a dragon- 
fly. Caddisflies were found once and caterpillar remains once. 
Ants were found twice, and remains of a few other hymenopterans, 
but amounted to very little in bulk. Fragments of spiders were 
found three times. The comparatively small number of miscel- 
laneous forms is surprising considering the manner in which the birds 
feed. 
VEGETABLE FOOD 
The vegetable food of the Wilson phalarope composed 6.7 per 
cent of the total and was made up almost entirely of seeds of aquatic 
plants or of plants that grow in marshy situations. Material that 
may be called vegetable rubbish was encountered 5 times and con- 
sisted of small particles that probably were obtained incidentally and 
swallowed by the birds when in eager pursuit of active prey. Seeds 
of pondweeds were found 6 times and of widgeon grass 5. Species 
of rushes (Scirpus) were identified 19 times, other sedges 6, and seeds 
of smartweed (Polygonum) 5 times. It will be noted at once that 
most of these seeds have hard outer coverings, and it seems prob- 
