BIRDS OF POETO RICO. 65 



adults except for the shorter bill. The usual color of the iris in this species is 

 grayish white, but iu many it was plain slate. 



These little birds are very active flycatchers, always watching overhead 

 for insects, and capturing them on the wing with a loud snap of the bill, or 

 picking them from the underside of leaves. In dry areas they frequently feed 

 actively about the tips of twigs, and work through more open localities than is 

 their usual habit. 



Food. — In 89 stomachs of the tody, animal matter forms 97.62 per cent and 

 vegetable 2.38 per cent. Flies, beetles, and small lantern flies form the most 

 important elements of the animal food, and a few seeds compose the vegetable 

 matter. In so small a bird the insects taken are of necessity of minute propor- 

 tions, and from field observations little could be learned save that they seemed 

 to feed to a considerable extent upon ants and small Homoptera. 



Animal food. — Forty-nine of the birds taken had eaten odd, forcep-tailed ear- 

 wigs, creatures of uncertain habit, and these form 9.4 per cent of the total. 

 Orthoptera were seldom taken and amount to 2.28 per cent. The larger part 

 of this is made up of grasshoppers, in six stomachs, while single birds had 

 eaten a roach, a locust, and a mantis, all of small size. Small Homoptera, all 

 of great economic importance, form 9.28 per cent. Small lantern flies (Ormenis 

 sp.) are known to attack the young shoots of coffee, while leaf hoppers (Tet- 

 tigonia sp. ) are injurious to small crops and undoubtedly to larger trees. Other 

 Hemiptera (1.11 per cent) comprise a miscellaneous assortment of ambush 

 bugs, stinkbugs, and scale insects, the last two each found five times. The red 

 scale (Lecanium sp.) was among those taken. Caterpillars in 9 stomachs and 

 moth remains in 18 form 5.21 per cent. Though remains of Diptera figure as 

 30.88 per cent and were eaten by 65 birds, they were so broken and ground up 

 that further identification was usually impracticable. Mosquitoes were identi- 

 fied certainly in one case and doubtfully in several others. They are, however, 

 so easily broken up that they readily escape notice. 



Beetles combined amount to 23.44 per cent, but the only useful ones found 

 are ladybirds (Coccinellidse). Though these occur in 21 stomachs, they amount 

 to only 1.59 per cent of the total food. Snout beetles (6.47 per cent) were 

 present in 46 stomachs. These can without doubt all be classed as injurious 

 and alone more than outweigh the useful beetles eaten. Leaf beetles — Chrys- 

 omelidse — (8.55 per cent) were present in 42 of the stomachs examined. Dia- 

 broticas and flea beetles of several species were the most common, and with them 

 were others of uncertain economic position. As a whole, however, this family 

 and the longicorn beetles (4.87 per cent) are to be considered injurious. The 

 Hymenoptera eaten (4.33 per cent) weigh in the balance against the bird, as 

 they are composed largely of parasitic chalcids and ichneumon flies. One pecu- 

 liar sawfly, a plant-feeding species, with curiously forked antennas, was found. 

 Though many ants are consumed, one of their principal parasites (Kapala sp.) 

 is eaten freely, being found in nine stomachs. Spiders in 38 stomachs amount 

 to 8.17 per cent. Among the most unexpected discoveries were the remains of 

 tiny lizards in five stomachs, and one can well imagine a vigorous struggle be- 

 tween this diminutive bird and some active anolis which objected to being 

 swallowed. These with a few insect eggs amount to 3.52 per cent. 

 9767°— Bull. 326—16 5 



