42 



BIRDS OF A MARYLAND FARM. 



Fig. 14.— Cutworm and moth (after Howard; 

 loaned by Division of Entomology). 



included leaf -hoppers, scale insects, and an occasional plant-louse and 

 giant water-bug. Of the Hymenoptera the insignificant proportion of 

 1.89 percent consisted of parasitic wasps, while the remainder was 

 almost entirely ants. The Lepidoptera were very nearly all caterpil- 

 lars, though moths were occasionally eaten. The caterpillars com- 

 prised the smooth forms, oftenest cutworms (fig. 14) and others 

 of the famil}^ Noctuida?, together with some Geometrid^ and occa- 

 sionally an arctiid or a sphingid. 

 The grasshoppers were long- 

 horned grasshoppers (Locustidffi) 

 and short-horned grasshoppers 

 ( Icridid^e), the latter consisting of 

 such forms as Hippiscus^ Melano- 

 jplus atlanis^ 3lelcmoj>lus femar- 

 ruhrum, and Dissosteira Carolina^ 

 the former largely of such meadow 

 grasshoppers as XijMdium and 

 Scudderia^ with an occasional 

 katydid. Beetles formed twice as 

 large an element of food as any 

 other order of insects. Ground- 

 beetles (Carabid^e), generally considered useful, formed 2.10 percent of 

 the food; injurious species, largely weevils (Rhvnchophora) and leaf- 

 beetles(Chiysomelid8e), and, to a smaller extent, lamellicorn and longi- 

 corn beetles, leaf -chafers, click-beetles, and metallic wood- borers 

 (Buprestid^e), amounted to 13.25 percent; while miscellaneous beetles, 

 largely dung-beetles of the genera Aphodlus (fig. 15), Ataenius^ and 

 Onthoj^hagus^ and beetles of a number 

 of other families, such as the Anthicidse, 

 Bruchidee, Byrrhida?, Histeridae, Staphy- 

 linidse, and Tenebrionidse, completed the 

 remaining 3.27 percent of the beetle food. 

 The spiders were largel}^ the ground- 

 spiders of the famil3^L3^cosida^. Spiders 

 are said to do about as much good as 

 harm, and are usually regarded as of no 

 economic importance. 



Beneficial insects (predaceous beetles 

 and parasitic wasps) formed 3.97 per- 

 cent of the food, while injurious insects, principally caterpillars, 

 grasshoppers, and harmful beetles, amounted to 26.80 percent. It 

 will be remembered, however, that what has already been said about 

 the destruction of useful species shows that but a small fraction of the 

 percentage of these insects should reaUy be counted against the birds. 



Fig. 15.— Dung-beetle {Aphodlus) (after 

 Prof. S. A. Forbes). 



