JULY 119 



sea-cliffs ; whereas the swallow, so far as I have seen, 

 invariably takes advantage of human architecture, how- 

 ever humble, to obtain overhead shelter. I cannot, 

 however, endorse from personal observation, Yarrell's 

 statement that the situation chosen for the nest is 

 1 most frequently a few feet down an unused chimney,' 

 although the Carolina wood-ducks, whereof we had a 

 pretty fleet on the Sanctuary Lake at one time, used to 

 surprise the householders in a village a mile distant 

 from the water by choosing that somewhat hazardous 

 place to build in. 1 Overhead shelter is essential to the 

 stability of the nests of both swallows and martins, 

 forasmuch as, being composed of earth glued into a 

 stiff paste by the builder's saliva, the structure would 

 soon dissolve if exposed to rain. A third species of 

 the swallow tribe, the sand-martin (Cotile riparia), 

 evades the vicissitudes of weather by burrowing deep 

 into any sandy bank and putting together a few feathers 

 and bits of grass as a cradle for its brood. 



The swift (Cypselus apus} resembles the swallows so 

 closely in its habits and general appearance, subsisting 

 like them upon flies caught on the wing and rearing its 

 young in a nest formed of earth moistened with saliva, 

 that it is popularly regarded as belonging to that 

 family; but its true affinity, as shown by important 



1 Our pretty wood-ducks are now but a pleasant memory. Originally 

 about sixteen in number, they dwindled in the course of years down 

 to one ; partly, I suppose, owing to their seasonal migratory tendency, 

 and partly because they used to go flighting at night at the risk of 

 getting shot. Bitter was the regret of my son who, returning one 

 night from flight-shooting, found a fine Carolina drake in his bag. It 

 is, of course, impossible to distinguish the plumage of any bird in 

 silhouette against a night sky. 



