418 BULLETIN 179, UNITED STATES NATIONAL MUSEUM 



These parasites are not a serious menace to the birds but in cases of 

 heavy infestations may cause a certain degree of discomfort especially 

 to young confined in the narrow quarters of their nest. 



The fleas C eratophyllus riparius and C. celsus have been found 

 in the burrows and nests as well as on the adult birds. Fleas may 

 be found in burrows and nests not occupied and probably persist 

 throughout the year in such situations. Leonard K. Beyer (1938) 

 states that fleas {C. riparius) bred abundantly in the material of 

 nests he had under daily observation at Sodus Bay on the southern 

 shore of Lake Ontario. He states that the fleas were often seen 

 crawling over the birds. Mites also infested them and the birds' 

 frequent scratching and picking at themselves were doubtless caused 

 by the attacks of these parasites. 



The most injurious external parasite of the nestling bank swallow 

 is the muscoid fly Protocalliphora splendida^ which is common among 

 birds examined in Maine colonies. Stoner (1936b) found that scores 

 of individuals examined in the Oneida Lake region, New York, in 

 1931 carried the larvae in various stages of development. These larvae 

 become attached to almost any part of the host's body by means of a 

 suctorial disk. They commonly enter the nasal and ear openings 

 where the skin is delicate and the blood supply generous. They are 

 also attracted by the rich supply of blood about the bases of the 

 rapidly growing tail and large wing feathers. They are also to be 

 found in the region of the vent and oil glands. According to Stoner, 

 the late or second broods are more heavily infested than earlier or 

 first broods of the season. 



In 10 out of 1,200 young and adult bank swallows examined by 

 Stoner there were diseased external parts. Four ju venal swallows 

 taken in June and July exhibited abnormal and seriously diseased feet 

 or tarsi or both. It is possible that there is a relation existing between 

 this infection and the occurrence of the Protocalliphora larvae. 



No extensive study has been made of the internal parasites of the 

 swallows, but Dr. Eloise B. Cram (1927) records the nematode para- 

 site Acuaria attenuata as being found between the tunics of the gizzard 

 in the bank swallow. The swallow served as the primary host of 

 this parasite. 



The bank swallow, which nests in such a well-hidden situation, 

 would not be expected to be a victim of the cowbird ; however, Fried- 

 mann (1929) reports a set of bank sw^allows' eggs taken at Lacon, 111., 

 by William E. Loucks, which contains six eggs of the swallow and 

 one of the cowbird. No details of the location of the nest, whether 

 exposed or in an exceptionally short burrow, are given. In all events 

 it represents a very unusual and purely accidental case. 



Fall. — The flocking of the bank swallow with other species of swal- 

 lows is one of the most striking features of their behavior during 



