406 BULLETIN 196, UNITED STATES NATIONAL MUSEUM 



they aggregate over 32 percent of the whole." Hemiptera make up 

 26 percent of the diet, including assassin bugs, lace bugs, leafbugs, 

 leafhoppers, jumping plant-lice, plant-lice, and scale insects. Beetles 

 were eaten to the extent of 13 percent, only 2 percent of which were 

 the useful ladybirds and the remainder all more or less harmful. 

 Butterflies, moths, and caterpillars were eaten rather sparingly, 

 aggregating only 3 percent of the whole. Flies amounted to 17 

 percent, and spiders and pseudoscorpions made up an additional 

 2 percent. 



The small amount of vegetable food was divided as follows: Fruit, 

 principally elderberries, less than 1 percent, weed seeds 0.01 percent, 

 and miscellaneous matter, including seeds of poison-oak and leaf galls, 

 over 4 percent. 



Dr. George F. Knowlton (MS.) lists the ruby-crowned kinglet among 

 the birds that eat the beet leafhopper in Utah; five birds examined 

 had eaten two nymphs and two adults. 



Milton P. Skinner (1928) gives the following account of the feeding 

 habits of this kinglet in North Carolina in winter: 



During the winter, they depend largely on small insects for food. At times 

 they are on the ground amid the fallen leaves, searching herbaceous plants less 

 than a foot high, or on the twigs of low bushes or shrub oaks, but often on the 

 three species of pines searching the trunks, limbs, twigs, and the bunches of 

 needles. When hunting the clusters of pine needles, the kinglets search carefully 

 at the base of each needle and in the pockets between the needles, frequently 

 swinging back down below the clusters, and sometimes hovering in mid-air on 

 fast-beating wings before the clusters. One kinglet that searched the tufts of 

 needles appeared to catch an insect every five or six seconds as long as I watched 

 it, and another one found something to eat on every four inches of pine limb that 

 it searched. Sometimes the Ruby-crowned Kinglets hunt insects in the cedars, 

 hollies, gums and dogwoods. In this limb and twig hunting, they depend chiefly 

 on picking insects from the bark, or on catching those that fly from the bark. 

 But many of these birds perch on limbs and dart on insects that attempt to fly 

 past them. Sometimes the Ruby-crowns collect dogwood berries from the 

 ground and eat them, but reject the seeds probably, and occasionally they take a 

 few sumac berries. More often they consume cedar berries, both pulp and seeds, 

 and some of the pulp from wild persimmons. 



Behavior. — The above account of the feeding habits of this kinglet 

 by Mr. Skinner gives a good idea of its behavior anywhere, for the 

 constant search for food is always the main activity of this busy little 

 bird. Mr. Skinner adds: "When they fly, these kinglets show a 

 peculiar, jerky, undulating flight that is more or less characteristic 

 of them." 



Except during the breeding season, the ruby-crowned kinglet is a 

 sociable bird, being seen on migrations and in winter loosely associated 

 with various other birds, such as warblers, bluebirds, titmice, nut- 

 hatches, creepers, golden-crowned kinglets, as well as with individuals 



