82 BIRDS OF CALIFORNIA AFFECTING FRUIT INDUSTRY. 



The following families of Hemiptera were recognized in the stom- 

 ach contents: Assassin-bugs (Reduviidse), lace-bugs (Tingitidse), 

 leaf-bugs (Capsidse), leaf -hoppers (Jassidse), tree-hoppers (Membra- 

 cidfe), jumping plant-lice (Psjdlidse), plant-lice (Aphididae), and 

 scale-insects (Coccidae). Stink-bugs (Pentatomida^), which are the 

 most universally eaten by birds of am^ Hemiptera, are entirely want- 

 ing. Evidently it was not- lack of opportunity that prevented the 

 kiufflets from eating the last-named insects, for other birds collected 

 at the same time and place had partaken of them freely. From the 

 human point of view it is not strange that birds should reject them, 

 for to us their odor is vile and their taste nauseous. It will be 

 noticed that the Hemiptera selected by the kinglet are mostly species 

 of small size, but happily they are the very ones that are the most 

 harmful to the interests of man. The tree-hoppers, the leaf-hoppers, 

 and the jumping plant-lice, when abundant, are pests, and often do 

 great harm to trees and smaller plants, while the plant-lice and scale- 

 insects are the worst scourges of the fruit grower — in fact, the preva- 

 lence of the latter has almost risen to the magnitude of a national 

 peril. As has been before pointed out, it is these small and seemingly 

 insignificant birds that most successfully attack and hold in check 

 these insidious foes of horticulture. 



Beetles of various families and species were eaten by the kinglet to 

 the extent of 13 percent of the season's food. They belong to species 

 that are more or less harmf4d, Avith the exception of a number of 

 ladybirds (Coccinellidae), which from their habit of feeding on plant- 

 lice are eminently useful. The damage done by the destruction of 

 these useful beetles, however, is small, since they aggregate less 

 than 2 percent of the Avhole food. Singularly, nearly all were in 

 stomachs obtained in February. In this month 8 percent of these 

 beetles were eaten, while in no other month was so much as 2 percent 

 taken. Another curious fact is that almost all of these belong to the 

 genus Scymnus, which is made up of minute black creatures Avhich 

 one might think would pass unnoticed by birds. On the contrary, 

 the small and insignificant individuals of this genus appear to be 

 eaten much oftener than the larger and more showy species. While 

 the eating of ladybugs by kinglets or other birds is to be deplored, 

 it must be acknowledged that, little harm is done so long as the num- 

 bers destroyed are as moderate as the above figures imply. 



Of the harmful beetles eaten the weevils are perhaps the most 

 interesting. One stomach contained 20 individuals, which seems 

 a large meal in view of the size of the bird. Manv of the weevils 

 belong to the family of engravers (Scolytidae), which live under the 

 liark of trees and are forest pests. Another beetle found in many 

 stomachs is Notoxus alamedce^ an insect that lives on trees, but which 

 does no harm so far as known. One stomach contained the remains of 



