262 HIRUNDINID^E. 



frequenting the habitations of men, its annual return is 

 not so regularly or so generally noticed. Mr. Heysham, 

 however, has recorded that so far north as Carlisle, this 

 bird has in two different seasons been noticed before the 

 end of March ; and there are other records of its having 

 been observed in Cumberland on the 4th and on the llth 

 of April. 



Like the species already described, this little wanderer 

 comes to this country from Africa, and frequents as its 

 nesting-place high banks of rivers, sand-pits, and other 

 vertical surfaces of earth that are sufficiently soft in sub- 

 stance to enable the bird to perforate it to the depth 

 necessary for its purpose. In such situations this little 

 engineer forms circular holes in a horizontal direction, 

 boring to the depth of two feet or more, with a degree of 

 regularity, and an amount of labour, that is rarely exceeded 

 among birds. The mode in which this perforation is 

 accomplished has been well described by Mr. Rennie, in his 

 Architecture of Birds, in the following terms, page 18: 

 " The beak is hard and sharp, and admirably adapted for 

 digging ; it is small, we admit, but its shortness adds to its 

 strength, and the bird works, as we have had an oppor- 

 tunity of observing, with its bill shut. This fact our 

 readers may verify by observing their operations early in 

 the morning through an opera glass, when they begin in 

 the spring to form their excavations. In this way we 

 have seen one of these birds cling with its sharp claws 

 to the face of a sandbank, and peg in its bill as a miner 

 would do his pickaxe, till it had loosened a considerable 

 portion of the hard sand, and tumbled it down amongst the 

 rubbish below. In these preliminary operations it never 

 makes use of its claws for digging ; indeed, it is impossible 

 it could, for they are indispensable in maintaining its 

 position, at least when it is beginning its hole. We have 



