°'i9H J Recent Literature. 285 



may infer that all possible distribution by birds would be of little importance 

 as compared with the good they would do in checking the increase of the 

 moth." 



The question as to distribution of gipsy moth eggs by birds has recently 

 been revived and as a coincidence by two independent investigators whose 

 results were published in the August issues of different entomological 

 journals. 1 Both of these articles deal with experimental feedings of caged 

 birds. Mr. William Reiff used the European Yellow-Hammer, Chaffinch, 

 Canary and Carrier Pigeon, the Japanese Robin, and one native species, 

 the Screech Owl. The moth eggs were mixed with or placed within other 

 food before they were given to the birds. The Canary and the Chaffinch 

 picked out and rejected most of the eggs, but a few that passed through the 

 alimentary canal of the former failed to hatch. Twelve eggs passed by the 

 Yellow-hammer likewise failed to hatch. Three out of 52 eggs passed by 

 the Japanese Robin hatched. Of 120 eggs concealed in the abdomen of a 

 mouse which was fed to a Screech Owl, 112 came through the alimentary 

 canal of the bird. Seven of these hatched. None of the eggs fed to the 

 Carrier Pigeon were found in the excrement. The writer concludes that 

 "Gypsy moth eggs can withstand the action of digestive fluids of birds 

 belonging to at least two families, Turdida? and Bubonida?, without suffer- 

 ing any, or only slight, injury. In regard to the family, Fringillida?, also 

 an insectivorous group," he says, "I am inclined to believe that these birds 

 might also occasionally distribute gypsy moth eggs in spite of the negative 

 results obtained in my experiments. Since the members of the pigeon 

 family grind up their food in a gizzard filled with small stones it is very 

 unlikely that gypsy moth eggs could pass through their intestines without 

 being destroyed." 



These conclusions are too sweeping; it would have been better to have 

 said that the eggs can sometimes withstand the action of digestive fluids 

 or that they have been shown to do so in a few cases under experimental 

 conditions. The conclusion regarding sparrows has no justification in 

 the experiments reported. Objections to this paper which apply equally 

 the one discussed below will be united with comments on that article. 



Mr. C. W. Collins experimented with English Sparrows and a pigeon. 

 The writer says: "The sparrow was chosen. . . .mainly because it has been 

 known to feed upon the eggs in confinement; the pigeon, merely to deter- 

 mine if the eggs would be digested. In all cases it was necessary to force 

 the birds to eat them." In the case of the English Sparrows this was done 

 by putting the eggs well into the mouth by means of a toothpick; and a 

 mixture of dough and eggs was forced into the pigeon's beak. Three of 

 the sparrows were confined in small boxes, and the ten used in the experi- 



1 Reiff, W., Some Experiments on the Resistance of Gypsy Moth Eggs to the 

 Digestive Fluids of Birds. Psyche, XVII, 1910, pp. 161-164. 



Collins, C. W., Some Results From Feeding Eggs of Porthetria dispar to Birds. 

 Journ. Ec. Ent., Ill, 1910, pp. 343-346. 



