WRENS. 59 
Other beetles, mostly leaf-beetles (Chrysomelide) were eaten to 
the extent of a little more than S$ percent. While nearly all of the 
leaf-beetles are theoretically harmful none of those identified in the 
food are especially destructive to crops. 
Hymenoptera, including both ants and wasps, aggregate a little 
more than 17 percent of the wren’s diet. They are a fairly constant 
constituent of the food and do not appear to vary much according to 
season. The greater number was found in March, but as only two 
stomachs were collected in this month the record is not conclusive. 
Ants form about 7 percent of the food. The economic relations of 
these insects have been discussed elsewhere. Wasps make up the rest 
of the item, about 10 percent, and have no especial economic signifi- 
cance. Caterpillars and a few moths and some cocoons constitute a 
little less than 12 percent of the wren’s food. Contrary to what 
might be expected, not all these are taken in summer. The 14 
stomachs obtained in February contained caterpillars to the amount 
of over 13 percent of their contents. They were probably found 
hibernating in crevices of bark. A few moths were eaten, but, as 
usual, they were only a small item of the food. Small cocoons’ of 
tineid moths were found in a number of stomachs. 
Grasshoppers amount to 4 percent of the wren’s diet. Most of 
them are eaten during the summer and fall, though some appeared in 
stomachs taken in January. While these insects are a favorite food 
for many birds they are probably rather large and too terrestrial in’ 
habits to be eaten in great numbers by wrens. Other insects, mostly 
flies and a few remains which could not be identified, make up about 
6 percent of the stomachs’ contents. Fles (Diptera) are eaten very 
irregularly and appear not to be relished. Spiders are taken to the 
extent of somewhat more than 5 percent of the total food. As spiders 
live about trees, bushes, fences, rocks, and outbuildings it is not sur- 
prising that they are captured by wrens, but the rule seems to be that 
while all insectivorous birds eat spiders to some extent no species eats 
many. 
List of insects found in stomachs of Bewick wren: 
COLEOPTERA. 
Cercyon fulvipenne. Diabrotica soror. 
Hippodamia convergens. Cryptocephalus castancus. 
Cocinella t. californica. Gastroidea sp. 
Scymnus marginicollis. Bruchus seminulion. 
Aphodius rugifrons. Blapstinus dilatatus. 
Microrhopala montana. Notorus alamede. 
Diachus auratus. Ceutorhynchus nodipennis. 
Crepidodera helrines. Pelenomus cavifrons. 
UMpitrir parvula. Apion sp. 
E-rena conspersa. 
