192 OUR SUMMER MIGRANTS. 



birds. In the Swift we find the toes short and 

 stout, and all four directed forwards ; the least 

 toe (which should be the hind one) consisting of 

 a single bone, and the other three of only two 

 bones apiece — a peculiar construction, but well 

 adapted for the purposes for which the feet are 

 employed. 



This singularity of structure has induced 

 naturalists to consider the Swifts (for there are 

 several species) generically distinct from the 

 Swallows ; and the former, therefore, are now 

 placed by common consent in the genus Cypse- 

 lus, a name adopted from Aristotle, and sug- 

 gested by Illiger, as indicating the bird's habit 

 of hiding its nest in a hole. 



The remarks which have been made upon 

 food in the case of the Swallows, apply equally 

 in the case of the Swifts. The latter have so 

 frequently been observed in localities presenting 

 very different species of insects, and sweeping 

 in the summer evenings through the midst of 

 little congregated parties of various kinds, that 

 there is little doubt that the nature of the food 



