NATURAL ENEMIES: BIRDS. OF 
control of these insects. No amount of “encouragement for the 
birds” or efforts to utilize their service in this direction can be 
expected to have any appreciable effect in reducing the number of 
leafhoppers, and we may dismiss this idea and turn our attention 
to other more hopeful agencies. 
It should be kept in mind distinctly that these conclusions refer 
only to the relation of birds to this particular class of insects and 
must not be used as an argument for or against the status of birds 
in relation to the control of insects in general or of any other group 
of pests. The writer is fully aware of the important service that is 
rendered by many of our common birds in the control of a number 
of serious insect pests and would by no means wish to contribute to 
any undervaluation of their service. 
The following list, with the leafhopper species arranged in alpha- 
betic order, shows the species of birds which have fed upon leaf- 
hoppers, the number of stomachs containing such material, with the 
total number of stomachs examined for each species and the per- 
centage for each record, as very kindly revised and corrected up to 
January 1, 1912, by the Biological Survey. 
Birds that have been found by stomach examination to have fed on leafhoppers,; the latter 
grouped by families. 
FULGORIDA. 
Ne ber 
pe, of stom- 
aes achs con- 
Name of bird. Name of insect. of stom- taining Percentages. 
achs ex- erm 
amined. family 
named. 
Chreturapelagiea 2.2.8... .......- Pulgoride): 20s et ere 137 2), aa 
Chordeiles virginianus.......-.--|.---- Ome ot ke setae wa caeee 266 4 | 2, trace, 1, 1. 
Otocorisialpesiris_= ..o_......2...|-4.- LO ye cy ee Sn ea “1,159 1/9. 
VITOR SnVORANAE 2. 2.2. eine LOS reales ee ante ee 74 Doleas 
Chordeiles virginianus........... Oliants anidus. 2.9252 es (*) 1 | 12 (12 spm.). 
Colinus virginianus............-- Scolops maculosus..........- 971 allie 
Lophortyx californicus.........-.- NCOLOPS SDenme beer ase ae 619 1 0: 
CERCOPIDA. 
Weeipiter COOPEr!.\-)..2--5-.---.-6 6. Cercopidieras eres ase 100 1 | Trace 
@hamisea fasciata-.=...-.-.......- Hateae DO Sire seed ee a 170 AD Make 
Geothlypis trichas............... joao COM Z E20 Set tLe 130 1°30: 
Tridoproene bicolor. .......-...... eaee? OOS Sae se ebay tan wee 164 1 | 10. 
Melospiza melodia................ Cereopidie (1 with 5 spm.).-- 718 3 | 15, 5, 100 
Otocorisjalpestriss ) i 2... ..-- 2. @ercopidee ke oe sass eee Bes () 2 ales 
Quiscalus quiscula..............- (Soe = dons: feces : 2,384 tA ee 
Sturnella magna... .... Z 1,157 Pa ae 
Penthestes atricapillus. . ae 644 3 | 50, 79, 90 
Polioptila ceerulea......-. tse dOu. 39 2 | 30, 20. 
Setophaga ruticilla............... EdOr wae 17 2 | 81, 50. 
SHIMON arth Soe oe a es 2 | COs seen 32 18 | 100, 88, 100, 20, 79, 
83, 90, 100, 77, 25, 
50,72, 45, 100,100, 
100, 85, 65. 
Thryomanes bewicki.............|..-.- DO. Mtomee ner if 153 1 Gs 
Chordeiles virginianus........... | Aphrophora sp ( 1 | Trace 
Chordeiles virginianus........... | Clastoptera xanthocephala (‘) 2 | Trace, 1 
(12 specimens. ) 
PUNCH AIKGHIUN 272.40. occ eck Ptyelusspeesoote-e ee 1 1 | 40. 
| 
1 Number of stomachs recorded elsewhere in this list. 
