12 BULLETIN 1249, U. S. DEPARTMENT OF AGRICULTURE. 



was over. Damage of this character is of very sporadic occurrence 

 as shown by the present stomach examinations. No trace of buds or 

 grain was found in any of the stomachs, as would have been the case 

 had bud and grain-eating habits been general with the species. 



Conclusions. — From the examination of 243 stomachs it is evident 

 that seeds of various conifers afford the red crossbill its chief sus- 

 tenance throughout the year. Other food is taken either incidentally, 

 as weevil larvae found within the seeds of pine, or because coniferous 

 seeds are not readily available. As these crossbills destroy no crops 

 and do not feed to any extent upon insects either beneficial or in- 

 jurious, they are of little economic importance. The only apparent 

 source of damage would be found in the bud-eating habit, and from 

 the results obtained in this investigation, appreciable injury of this 

 kind seems a remote possibility. The red crossbill may well be 

 afforded protection because of its interesting ways and its presence 

 at a time of year when bird life is scarce. 



Food items -of the red crossbill, identified to the genus or species, as determined 

 by the examination of 248 stomachs. 



[The figures indicate the number of stomachs in which the items were found.] 



Vegetable Food. 



Pinaceae. 



Pinus strobus (white pine) 2 



Pinus Virginian a (scrub 



pine) 52 



Pinus echinata (shortleaf 



pine) 1 



Pinus ponderosa (western yel- 

 low pine) 80 



Pinus resinosa (red pine) 8 



Pinus sp. (pine) 100 



Pinaceae — Continued. 



Picea engelmanni (Engelmann 



spruce) 1 



Picea sp. (spruce) 3 



Larix sp. (larch) 1 



Tsuga canadensis ( hemlock ) 5 



Cyperaceae. 



Scirpus sp. (bulrush) 1 



Ambrosiaceae. 



Ambrosia elatior (ragweed)— 1 



Animal Food. 



Cicindelidae (tiger beetles). I Vipionidae (parasitic wasps). 



Cicindela sp 1 I Microbracon sp 1 



WHITE- WINGED CROSSBILL (Loxia Uncoptera). 



(Plate II.) 



The white- winged crossbill is a bird of more northern distribu- 

 tion and appears more rarely and irregularly within the borders 

 of the United States than the preceding species. It closely resembles 

 the red crossbill in habits and general appearance, the most notice- 

 able difference being the two white wing-bars which give to this 

 bird its name. It usually appears in small flocks. Occasionally the 

 two species are found flocking together. 



Fifty-two stomachs were available for the study of the food 

 habits of the white-winged crossbill ; but as over half of these were 

 collected in two widely separated localities in February and Septem- 

 ber, the material is very unequally distributed geographically and 

 seasonally. For this reason no attempt is made to ascertain monthly 

 percentages and the entire number is treated as a unit. Of the 

 total contents of these 52 stomachs 6.88 per cent is animal matter and 

 93.12 per cent vegetable. 



