274 MIGRATION OF ANIMALS. 



appear in Britain soon after the house-swallow. They ouild 

 under the eaves of houses. The nest is composed of the 

 same materials as those of the house-swallow ; but it is cov- 

 ered above, and a small hole only is left in the side for the 

 ingress and egress of the birds. The martins totally disap- 

 pear about the beginning of October. 3. The sand-martin, 

 or bank-martin, is by much the smallest of the swallow kind 

 that visit Britain. The sand-martins arrive very soon after 

 the house-swallow, and disappear about Michaelmas. They 

 dig considerable holes in sand-pits and in the banks of rivers, 

 where they build their nests, which consist not of mud, like 

 those of the former species, but of grass and feathers laid 

 together in a very slovenly manner. It is worthy of remark, 

 that these birds do not employ the cavities they dig in sum- 

 mer for winter quarters ; since sand-banks, so perforated, 

 have been carefully searched in the winter, and nothing found 

 but empty nests. 4. The swift, or black-martin of Willough- 

 by. is the largest of these swallows, and is the latest in arriving 

 in the country ; for the swifts are seldom seen till the begin- 

 ning of May, and commonly appear, not in flocks, but in 

 pairs. Swifts, ]ike the sand-martins, carry on the business 

 of incubation in the dark. They build in the crannies of 

 castles, towers, and steeples. Straw and feathers are the 

 materials they use. They disappear very early ; for they are 

 almost never seen after the middle of August. 5. The goat- 

 sucker, which belongs to the swallow tribe, is likewise a bird 

 of passage. Like the other swallows, it feeds upon winged 

 insects. But, instead of pursuing its prey during the day, it 

 flies only in the night, and seizes moths and other nocturnal 

 insects. From this circumstance, it has not improperly re- 

 ceived the appellation of the nocturnal swallow. The goat- 

 sucker stays only a short time in Britain. It appears not till 

 about the end of May, and retires in the middle of August. 

 It lays its eggs, which are commonly two and sometimes 

 three, on the bare ground. 



Herodotus and Prosper Alpinus mention one species of 

 swallow which resides in Egypt during the whole year ; and 

 Mr. Loten, late governor of Ceylon, assured Mr. Pennant, that 

 those of Java never remove. If these be excepted, all the 

 other known kinds retreat or migrate periodically. Swallows 

 migrate from almost every climate. They remove from Nor- 

 way, from North America, from Kamtschatka, from the tem- 

 perate parts of Europe, from Aleppo, and from Jamaica. 



Concerning the periodical appearance and disappearance 



