August, '10] COLLIXS: BIRDS AND PORTHETRIA EGGS 343 



submitted for examination by the State Department of Agriculture, 

 were found infested by a Chermes which was provisionally determined 

 as the above named species by both Dr. A. D. Hopkins of the U. S. 

 Bureau of Entomology and the writer. This appears to be the first 

 record of the introduction of this insect into America. It has been 

 recorded by Gillanders as very destructive to young silver firs, com- 

 paratively young specimens of Ahies nordmanniana and even fairly 

 old trees of Ahies nohilis. He states that young silver firs in nurseries 

 are often killed outright by this insect. The data at hand justifies 

 us in considering this species a dangerous form which should be 

 excluded if possible. 



SOME RESULTS FROM FEEDING EGGS OF PORTHETRIA 

 DISPAR TO BIRDS^ 



By C. W. CoLLixs, JJ. S. Dep't. of Agriculture, Bureau of Entomology, Mel- 

 rose Highland-s, Mass. 



The question is ofttimes asked, "Do birds eat the eggs of the gipsy 

 moth?" Several years ago Mr. E. H. Forbush stated that "No bird 

 has actually been proved to feed upon the eggs except the English 

 sparrow. One of these birds which was kept in confinement ate a 

 few of the eggs from time to time when deprived of other food, but 

 did not appear to relish them.''- There is a possibility that some 

 species may eat the eggs when other food becomes scarce. The latter 

 often happens during the winter when Porthetria dispar eggs are 

 found on trees, fences, stonewalls and in various other places for ten 

 months of the year and may offer some temptation to birds at such 

 critical times. The agents and inspectors engaged in gipsy moth work 

 frequently report having seen egg clusters which have apparently been 

 broken by birds. 



At the suggestion of Mr. W. F. Fiske some experiments in feeding 

 birds were conducted. Some English sparrows and a pigeon were 

 secured. One of the purposes of the investigation was to determine 

 the condition and vitality of the eggs after having passed through 

 the digestive tract. The sparrow was chosen for the experiment 

 mainly because it had been known to feed upon the eggs in con- 

 finement; the pigeon, merely to determine if the eggs would be di- 

 gested. In all cases it was necessary, to force the birds to eat them. 



^ Occasional contributious from the Gipsy Motli Parasite Laboratory, V. 

 = Mass. Board of Agriculture. "The Gypsy Moth." 1896, p. 231. 



