64 BIRDS OF CALIFORNIA AFFECTING FRUIT INDUSTRY. 
pests in the very places where their mischief is done. This can not 
be asserted of the marsh wren, but it must be remembered that many 
harmful species of insects breed and live in marshes and waste places 
as well as in grainfields and orchards, so that the birds which 
destroy them on wild lands are removing the source of supply from 
which are recruited the hosts that infest the farm. 
CACTUS WREN. 
(Heleodytes brunneicapillus. ) 
(Pl. IV.) 
The cactus wren is so exclusively a bird of the desert and waste 
places that its food may be thought to have little, if any, economic 
interest. It is not safe to assume, however, that the bird will never 
affect the interests of agriculture because it does not do so at present. 
Moreover, its food habits have a scientific interest which justifies a 
brief review. A number of the birds whose stomachs have been 
examined for this work were taken near orchards and grainfields, 
and there can be little doubt that, with the spread of cultivation, the 
species will adapt itself to a somewhat different environment and 
become of economic importance. We find, in fact, that its food is 
made up of practically the same orders and families of insects that 
compose the diet of birds living on agricultural lands, but the relative 
proportions differ widely, and in most cases the species are probably 
different. 
Only 41 stomachs of the cactus wren were available for examina- 
tion. They were taken in the region from Los Angeles to San Ber- 
nardino, and from July to January, inclusive. They contained about 
83 percent of animal matter to 17 of vegetable. 
Animal food.—Beetles and Hymenoptera, the latter ants and 
wasps, were the two most important items of the animal food. Each 
made up about 27 percent of the total. The beetles belong to several 
families, but weevils, or snout-beetles, were the most noticeable, and 
amount to somewhat more than 10 percent. One stomach contained 
11 of these insects and another 10, while others held fewer. Only 
one species, Rhigopsis effracta, was identified. ive of these were in 
1 stemach. The other beetles belang {o mere common families. 
Ceceinellids were found in 1 stomach and. carrion beetles in. 2. 
They were the only insects noted that can be considered as useful. 
THymenoptera are represented by many ants and a few wasps. These 
are just the insects which the cactus wren might be expected to find, 
for dry land and sunshine are the conditions which favor these crea- 
tures. Grasshoppers amount to a little more than 15 percent. This 
