Flight. 
Food. 
General 
descrip- 
tion. 
134: INSECTIVORI. CYPSELUS. SWIeT. 
wing; in fine weather flymy at a great height, and deseri- 
bing extensive circles with an easy sweeping motion; in a 
damper state of the air its flight is nearer to the ground ; in 
both cases regulated by the situation of its insect prey, which 
is higher or lower as directed by the atmospheric changes. 
It has been remarked that these birds delight in sultry wea- 
ther, with approaching thunder stcrms, at such times flying 
in small parties, with peculiar violence, and as they pass near 
steeples, towers, or corners of buildings, uttering loud 
screams, which Wuires, in his Natural History of Selborne, 
supposes to be a sort of serenade to their respective families. 
This is fanciful and pretty ; but I should rather be inclined 
to reason the opposite way, and to consider this action and 
cry as the consequences of irritability, excited by the highly 
electrical state of the atmosphere at such times *. ‘The above. 
mentioned scream is the only note this bird possesses. Like 
the Swallows, it is frequently seen skimming the surface of 
lakes and rivers in pursuit of its food, and, like them also, 
it both drinks and baihes upon the wing. The shortness 
of the tarsi, and the great length of the wings, render the 
Swift unable to rise from an even surface ; it is therefore (as 
if conscious of such inability) never seen to alight on the 
ground. It can, however, fix itself with ease against the per- 
pendicular face of walls or rocks, by means of its strong toes 
and hooked claws, which are disposed in a totally different 
manner from those of all other genera. 
It is found throughout the Old Continent, but has not been 
met with in America. According to TEmMMinck, it does not 
migrate beyond the ‘Tropics. 
Puate 42. Fig. 4. Natural size. 
Bill black. Throat smoke-grey. ‘The rest of the plumage 
greenish-black, with reflections; the feathers close in 
texture, and firmly pressed together. ‘Tarsi covered 
with small feathers. Irides brown. 
* See note in the account of the Green Woodpecker. 
