88 General Notes. [^^'^^ 



Hough records the presence in this country of two species in 1899 (see 

 Zoolog. Bull., Vol. II, p. 289), stating that they are very rare. I find also 

 that a specimen of one of these species {Protocalliphora chrysorrhoea) is in 

 the National Museum from the top of the Las Vegas rango, New Mexico, 

 and a second from the White Mountains of New Hampshire, the latter 

 collected by H. K. Morrison, probably about the year 1875. 



The subject is not without interest to bird lovers, since during the past 

 summer two successive broods of Bluebirds in Wellesley Hills, Massachu- 

 setts, were parasitized by one of the species, and of the eight nestlings 

 only one escaped. The living larvse and pupse from the second brood 

 were forwarded to the Bureau of Entomology in Washington and the flies 

 were reared and were identified by Mr. Coquillett as Protocalliphora chrysor- 

 rhoea Meigen. In appearance this fly so closely resembles a common blue 

 bottle as to be readily mistaken for it. Instead of laying its eggs on 

 carrion, however, this fly lays them more or less frequently on nestling 

 birds, upon the living flesh of which the maggots feed. Truly, sometimes 

 mother Nature seems to be a bit indifferent to the sufferings of her creatures. 



How common these flies are in Massachusetts and how extensive their 

 range is in the United States no one seems to know, but it is to be hoped 

 that bird students will bear the matter in mind and report all cases of 

 parasitism coming to their attention. Should they have bird boxes, if 

 they suspect anything wrong with the broods, it will be well to promptly 

 examine the nestlings and destroy the parasites in whatever stage they 

 may happen to be. 



Possibly birds that build in boxes or holes, like Swallows, Bluebirds, 

 Woodpeckers, Wrens and others, are more likely to be victimized than 

 those rearing their young in open nests, but the latter sometimes suffer 

 in Europe, and "it is highly probable that the young of our Robins, Song 

 Sparrows, and others of our native species also may serve as hosts of 

 this fly. The loss in the two broods noted above was nearly 90 per cent., 

 and if these flies become at all numerous (even now they may be com- 

 moner than is suspected) our native birds will be threatened by a new 

 danger. 



For the facts in regard to the Bluebirds and for the specimens by means 

 of which the identity of the parasitic fly was determined we are indebted 

 to Mrs. Emma F. Everett, of Wellesley Hills, whose solicitude for the 

 welfare of her Bluebird tenants prompted investigations which led to the 

 discovery of the parasites. — H. W. Henshaw, Biological Survey, Wash- 

 ington, D. C. 



