THE HOUSE MARTIX — THE SWALLOW. 337 



To examine minutely the economy of a Martin's nest is a pleas- 

 ant task enough, but has its drawbacks, which are very numer- 

 ous, and may be summed up in one word — vermin. 



All birds are liable to the attacks of parasitic insects, but the 

 Martins contrive to harbor such quantities of them that the spec- 

 tator can not but wonder how they contrive to live through the 

 constant attacks. The nest itself swarms with them ; and so nu- 

 merous are their hosts, that I have found an isolated lump of clay 

 filled with these repulsive insects, though at the distance of eight- 

 een inches from the nest. They are not visible at first, and but 

 for their cast skins would probably attract no notice. But when 

 one of these innocent-looking pieces of mud is removed, and put 

 under a glass in which a few drops of spirits of turpentine have 

 been placed, the vermin come trooping out of every crevice, many 

 in numbers, large in dimensions, and obese in outline. 



In one lump of clay about as large as a walnut I have seen so 

 man}?" parasites that they seemed capable of devouring all the lit- 

 tle birds ; and when it is remembered that every portion of the 

 nest is equally tenanted, how the inmates can survive for a single 

 night is indeed a matter of surprise. Their size is absolutely 

 portentous ; for, when compared with the birds on which they 

 feed, they are as large as full-grown frogs compared with men. 

 I mention this circumstance in order that my readers may be 

 chary of bringing a Martin's nest into a room, for to introduce 

 such pests into the house is far more easy than to extirpate them. 

 Most insects are killed at once by inhaling the vapor of turpen- 

 tine, but I have kept a number of them shut up in a tin box in 

 which some spirits of turpentine had been poured, and after six- 

 and-thirty hours found them still alive. They certainly dislike 

 the vapor, and it has the -effect of stupefying them ; but, as soon 

 as they are removed from its influence, the fresh air seems to re- 

 store them, and they begin to crawl about again. 



The common Swallow {Hirundo rusticd) also makes a clay- 

 built nest, similar in many respects to that of the martin, but dif- 

 fering in its shape. The nest of the martin is always covered, 

 and entered by an aperture on one side. Mostly it is built im- 

 mediately under a projecting ledge, which answers the purpose of 

 a roof, but if no such accommodation can be obtained, it covers in 

 the nest with a dome-like roof. The nest of the Swallow, on the 

 contrary, is open at the top, probably because the long forked 



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