THE CLIFF-SWALLOW. 37 
practised by a species of the mason bee (Anthophora 
retusa, LEacnh). 
As there is no masonry nor plastering made use 
of in the interior of the nut-hatch’s nest, we might 
have been inclined to consider the preceding account 
as purely fanciful. But we have the testimony of a 
recent observer, not only to the fact of the clay bar- 
ricade, but a confirmatory circumstance not a little 
interesting and curious. Colonel Montagu discov- 
ered that if the clay barrier at. the entrance of the 
hole be destroyed while there are eggs in the nest, 
it is speedily rebuilt to prevent, possibly, the unwel- 
come intrusion of the woodpecker, and other birds 
of superior size and strength, which build in similar 
situations. It appears to us no less probable, that 
the wall may be constructed to prevent the unfledg- 
ed young from tumbling out of the nest when they 
begin to stir about; for all young birds become very 
restless as they approach the period when they ac- 
quire the power, as well as the desire, for rapid 
movement. ‘The callow brood of most nests have 
the same impatience that distinguishes children who ° 
are about to use their legs: they pant to “imp their 
young wings.” 
The cliff-swallow (Hirundo fulva, Vie11107) is stri- 
kingly characterized by having an even and not a 
forked tail, like its congeners. Instead of a white 
rump, also, like our window-swallow, it has an iron- 
brown one, and the same colour, but of a darker 
shade, under the chin, where our chimney-swallow 
is red. The upper part of the body, however, has 
the same glossy violet black, and the wings the same 
deep brownasthe former. ‘ This active little bird,” 
says Bonaparte,* “ is, like its congeners, almost con- 
tinually on the wing, and feeds on flies and other 
insects while performing its erial evolutions. Its 
note is different from that of other swallows, and 
may be well imitated by rubbing a moistened cork 
* See Bonaparte’s Birds. 
