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tify the particles of many kinds of food found in the stomach, which 
would be impossible of identification by one who works in the labora- 
tory only. 
The earlier observations made were valuable in so far as they showed 
that many species of birds were feeding on hairy caterpillars, some of 
them continually, others intermittently, and others attacking them 
only as they came in their way. But to get a definite idea of the use- 
fulness of the different species in this respect it was necessary to count 
the number of caterpillars eaten by them in a given time and to note 
the frequency of their visits to infested trees or localities. 
During this work some very interesting facts have been observed. 
In explanation of the large numbers eaten it should be stated that the 
smaller birds feed mainly on the smaller or younger caterpillars; or, 
when feeding on the larger caterpillars, eat only a portion of each cater- 
pillar. They are thus enabled to do fully as good service as some of 
the larger species. Birds frequently visit localities infested by hairy 
caterpillars, most of them making short and frequent visits. Mr. 
Mosher was requested to time such visits and, where it was possible, 
count the number of caterpillars eaten during a visit. 
Time and space will not allow a transcription of notes of such obser- 
vations here, but an abbreviated table is given below, containing 
results of such observations made by Messrs. F. H. Mosher and A. H. 
Kirkland. 
BIRDS THAT FEED ON LARVA OF PORTHETRIA DISPAR. 
July 13. A cuckoo ate 1 every 2 minutes for 36 minutes. 
July 13. A red-eyed vireo ate 73 in 40 minutes. 
July 14. A yellow-billed cuckoo ate 81 in 48 minutes. 
July 15. A towhee ate 7 pup and 2 caterpillars in a very short time (exact time 
not noted). 
May 12. A yellow warbler ate 15 caterpillars in less than 5 minutes. 
May 12. A Nashville warbler ate 42 caterpillars in one-half hour. 
May 18. A scarlet tanager ate upward of 30 caterpillars within 5 minutes. 
May 18. Two scarlet tanagers together ate small caterpillars at the rate of 35a 
minute for 18 minutes. 
May 20. A crow blackbird ate 40 caterpillars in a little over 3 minutes. 
May 26. A Marylaud yellow throat ate 52 caterpillars while moving in and out 
among trees (time could not be counted). 
May 26. A redstart ate 31 caterpillars while moving about (time could not be 
accurately taken). Es 
May 26. A red-eyed vireo ate, in 4 brief visits to a tree infested by Porthetria 
dispar, 37 caterpillars. 
BIRDS THAT FEED ON LARVZ OF EUPROCTIS CHRYSORRHGA. 
May 2. A robin pecked into a mass of caterpillars five times, taking a number 
each time. They could not be counted. 
May 11. A pair of blue jays ate 47 caterpillars in 18 minutes. 
May 11. A black-and-white warbler ate 15 caterpillars in 10 minutes. 
May 12. A rose-breasted grosbeak ate 57 caterpillars in 20 minutes. 
