108 BIRDS OF A MARYLAND FARM. 



ants, 3 insect eggs, 3 spiders, and 3 caterpillars (measuring worms, 

 Geometridfe and hairy Arctiid^e, which are nsually avoided by birds). 

 One of the stomachs examined contained katydid eggs and two others 

 eggs of the wheel-bug. Between 200 and 300 eggs of the fall canker- 

 worm have been found in the stomach of a black-capped chickadee 

 and ttoO eggs of a plant-louse in that of another. The eating of insect 

 eggs is a characteristic habit of the chickadee, and makes the bird, 

 small as it is, one of the most effective destroyers of insect pests. It 

 is of particular value in the orchard, and every horticulturist would 

 do well to encourage it. 



KINGLETS. 



The golden-crowned kinglet {Regulus satrajya) and the ruby-crowned 

 kinglet {Regulus calendula) are useful insectivorous midgets. They 

 were observed at Marshall Hall, but were not killed. 



GNATCATCHERS. 



Three blue-gray gnatcatchers (Poliojjtila Ccerulea) were collected. 

 They had eaten longicorn beetles, joint-worm flies, caddis-flies, and 

 several minute flies (unindentilied Diptera). 



THRUSHES. 



The wood thrush {Hylocichla mustelina), Wilson thrush {HylocicJda 

 fusccscens)^ hermit thrush {Hylocichla guttata jxdlasi)^ gray-cheeked 

 thrush {HylocicJda alicise)^ and olive-backed thrush {Hylocichla ustu- 

 lata swainsoni) were noted at Marshall Hall —the first as a breeding 

 bird, the last four as migrants. 



Three stomachs of the gray-cheeked thrush were taken May 15, 

 1900. They contained saw-fly larva?, ants, caterpillars, Ma3^-flies, 

 ground-beetles, weevils, and scarab^eid beetles {Anomala^ Atsenius, 

 Lachiiosterna^ and Serica). 



Two olive-backed thrushes, also collected in May, had eaten ants 

 {Campoiiotus jyennsylvanicus) ^ wasps {Tiphia inornata)^ ground-beetles, 

 darkling-beetles {Helojys)^ and ground-spiders (Lycosida?). 



The robin {Merula niigratoria^ fig. 41) is seen on the farm only during 

 the colder half of the year. One bird collected in the blizzard of the 

 third week of February, 1900, had fed on smilax berries. Field obser- 

 vations and the examination of stomachs collected elsewhere show that 

 somewhat more than half of the robin's food is fruit. That which it 

 takes at Marshall Hall, however, consists merely of wild berries. In 

 the second week of April, 1899, 8 birds were collected. Five had eaten 

 ground-beetles, and four, secured in a field that was being plowed, had 

 taken large quantities of the larvae of the ground-beetle, Harpalus 

 caliginosus^ which as before stated has lately been found harmful to 



