28 BULLETIN 107, U. S. DEPARTMENT OF AGRICULTURE. 
is especially adept at hulling even the hardest and smallest of seeds, 
the partly digested embryos gave no clue as to their identity. 
The house finch may render some service in checking the increase 
of the weevil by destroying adults early in the season, but owing to 
its almost exclusively vegetarian diet this must be small. Whatever 
worth this species has lies in its consumption of weed seeds. 
PINE SISKIN. 
(Spinus pinus.) 
The stomach of the only pine siskin examined contained traces of 
an adult alfalfa weevil, but from what is known of its food habits 
in other parts of its range, this bird can not be regarded as important 
as a weevil destroyer. It is primarily a seed eater, and its animal 
food is confined mainly to such forms as plant lice and scale insects. 
WESTERN VESPER SPARROW. 
(Pocecetes gramineus conflnis.) 
The western vesper sparrow arrives in the Salt Lake Valley in 
March, when, during cold, blustery days, it may be found often in 
parties of three to six flitting about weed patches, usually not far 
from the protecting cover of a creek bottom. Later in the season 
it is a common breeder in the sagebrush areas adjacent to cultivated 
fields, and from here it makes regular trips to alfalfa fields in search 
of the weevil. 
In April, 16 of these birds were collected in alfalfa fields. All 
but three had fed on adult weevils, which amounted to about a twelfth 
of the food. The small size of the stomachs means that in numbers 
the weevil will be limited. An average of a little less than two adult 
weevils per bird was maintained for this month, while eight weevils 
is the highest record of a single bird. 
Other investigators have shown that the food of this bird varies 
from wholly vegetarian in midwinter to upward of 90 per cent ani- 
mal during summer. In Utah insect life began to form an appre- 
ciable portion of the food in April, and amounted to a little less than 
a quarter of the stomach contents. A third of this was the alfalfa 
weevil. Of the other items the clover- root curculio (Sitones sp.) 
occurred frequently and totaled about 4 per cent of the contents. 
Fourteen of these were found in one stomach. Dung beetles (Apho- 
dius) formed about an equal amount, while the remaining animal 
food was divided in small quantities under several heads. Of the 
vegetable food (76 per cent) about 19 per cent was grain and 57 per 
cent weed seeds. The latter element was present in all but one of 
the stom&chs and in four instances formed practically the entire con- 
