38 BIRDS OF A MARYLAND FARM. 



29, 1898) had made the bulk of their food of them. The genus is 

 not exclusively carnivorous, for it has been known to feed on seeds 

 of grasses and weeds, and recently (1900) has been discovered eating 

 strawberry seeds to a harmful extent. One grower at Leechburg, 

 Pa. , lost on a quarter-acre patch |350 in three nights through their 

 depredations." The nature of the injury has so far made remedial 

 methods impracticable; consequently the predatory habit of birds is 

 valuable in this case. 



There- is an increasing tendency to doubt the utility of ground- 

 beetles as a class. A European species (Zabrus gibbus) is a notorious 

 grain pest, and an American species {Agonoderus palUpes) has recently 

 been ascertained to feed sometimes on newly planted corn. Professor 

 Forbes has shown that the food habits of ground-beetles vary with 

 the structure of their jaws, species with sharp-curved jaws being 

 carnivorous, while those with blunt jaws are decidedly vegetarian. 

 Only a few — probably less than half a dozen — of the Marshall Hall 

 birds examined had destroyed the more carnivorous species. It is 

 probable, therefore, that birds do no appreciable harm in then.- rela- 

 tion to ground-beetles, but may even do some good by reducing the 

 numbers of such species as have vegetarian habits and occasionally 

 become pests. The following is a list of the different ground-beetles 

 found in the stomachs collected: Aniara, Anisodaotylus agricola, A. 

 rustieus, BemMdiuni, Cratacantlms diihius, Ohlsenius sestivus, Ilarpalns 

 caliginosus, II. pennsylvanicus, and several smaller species of Ilar- 

 palns. These had been eaten by 82 birds of the following 35 different 

 species: 



List of birds examined whose stomachs contained ground-beetles. 



Woodcock. Eusty blackbird. Louisiana water-thrush. 



Spotted sandpiper. Crow blackbird. Maryland yellow-throat. 



Bobwhite. Savanna sparrow. Chat. 



Downy woodpecker. Grasshopper sparrow. Mockingbird. 



Flicker. Henslow sparrow. Catbird. 



Kingbird. White-throated sparrow. Brown thrasher. 



Great crested flycatcher. Chipping sparrow. House wren. 



Phoebe. Junco. Gray-cheeked thrush. 



Blue jay. Song sparrow. Olive-backed thrush. 



Crow. Towhee. Robin. 



Red-winged blackbird. Cardinal. Bluebird. 



Meadowlark. Water-thrush. 



Ladybirds. — The most useful of all beetles are the members of the 

 family Coccinellidfe, commonly known as ladybirds, which with their 

 larvae are voracious feeders on insect pests. Only three of the Mar- 

 shall Hall birds — a long-billed marsh wren, a song sparrow, and an 

 English sparrow— were found to have destroyed these valuable insects. 



a Bull. Cornell Univ. Agric. Expt. Sta., p. 150, 1901. 



