y^ SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 85 



Some curiosity may be felt as to the relations of birds to the large 

 Scarabaeidae and Lucanidae with thoracic horns and especially strong 

 or greatly enlarged mandibles. In nearctic America we have few 

 species in any of these groups ; another limiting factor important in 

 relation to bird predators is the large size of these beetles. Never- 

 theless all of the genera are represented in the food o-f birds, Passahis 

 by 32 records, Plafycercus by 19, Lucamis by 25, Ceruchns by three, 

 Dorcns by six, Sinodcndron by seven, and lucanids further unidentified 

 by 28 determinations ; our largest scarabaeid, Dynastcs is represented 

 by five identifications, Strategns by 27, Xyloryctes by seven, Copris 

 by 62, and PJianaeus by 252. The latter genus, besides being 

 " horned," has brilliant metallic colors. 



The long-horned beetles or Cerambycidae include many species 

 with showy colors, but selectionists as a rule have not attributed dis- 

 tasteful qualities to the group ; rather they have considered these 

 beetles mimics of various more strongly " protected " insects such as 

 wasps and other Hymenoptera and weevils. Numerous longicorns 

 have cryptic coloration also, but their chief defense must be residence 

 of the long larval stages in wood where they can be reached only by 

 a small proportion of insect predators. The imago state, only in whicli 

 the colors theorized about are displayed, is of relatively short duration. 

 Bearing these facts in mind we believe the records show that longi- 

 corns are fed upon to such an extent as to indicate that in proportion 

 to availability they contribute their due share to the subsistence of 

 birds. 



The total number of determinations in the present tabulations is 

 1,585, shared by 162 species of birds. Twenty-one kinds of birds have 

 from 10 to 19 records each ; six additional species from 20 to 29; six 

 others from 30 to 39 ; one other 42 ; still another 53 ; and two as many 

 as 169 and 173 respectively. The woodpeckers, on account of their 

 peculiar qualifications for obtaining the larvae, naturally are the chief 

 enemies of Cerambycidae. Several of the species prey upon these 

 beetles to the extent of from 10 to 50 per cent of their total food. The 

 number of adult beetles taken at a meal by these or other birds ex- 

 ceeded 30 in a number of cases and in four ran as high as 83, 100, 

 102, and 168. The last named figure is for one of our most wasplikc 

 species, Xylotrechus colonus, in the stomach of a raven. There are 

 10 identifications of Xylotrechus ; of the other wasp-colored long- 

 horns, we have the following numbers of determinations: Cyllene, 10 

 (28 specimens of C. rohiniae in the stomach of a magpie) ; Calloides 

 nobilis i, Ncoclytus 11, Clytanthus 12, Clytcs 5, Strangalia 6, Typo- 

 cenis 16, and Lcptura 39. It is noticeable that the numbers appended 



