SOLITARY AND GREGARIOUS. 63 



storms*." Buffon says a sportsman told him he 

 had often found more than twenty collected in the 

 same holef. 



We are informed by an intelligent friend, that he 

 once found several wrens in the hole of a wall, rolled 

 up into a sort of ball, for the purpose, no doubt, of 

 keeping one another warm during the night ; and 

 though such a circumstance is only to be observed 

 by rare accident, we think it very likely to be nothing 

 uncommon among such small birds as have little 

 power of generating or retaining heat in cold 

 weather. This very circumstance, indeed, was ob- 

 served by the older naturalists. Speaking of wrens, 

 the learned author of the Physicae Curiosae says, 

 " They crowd into a cave during winter to increase 

 their heat by companionship J." 



Those who keep wrens in cages usually furnish 

 them with a box, lined and covered with cloth, 

 having a hole for entrance, where they may roost 

 warmly during the night . Yet even in keen frost 

 the wren does not seem, in the day-time, to care 

 much for cold, since we have in such cases fre- 

 quently heard it singing as merrily as if it had 

 been enjoying the sunshine of summer, contrary to 

 the remark of White ||, that wrens do not sing in 

 frosty weather^]". 



During a fall of snow, sheep seem both to take 

 advantage of natural shelter, and to huddle together 

 in order to economize their animal heat ; and they 

 accordingly, during a snow-storm, always flee to the 

 nearest shelter, though this is certain to end in their 

 destruction, if the snow fall deep and lie long. It, 



* Illustrations of Brit. Ornith. i. 197. 



f Ois. Art. Le Roi-telet. 



J Multi uno specie in hyeme conduntur, ut parvus in tarn rai- 

 nutis corporibus calor societate augeatur, p. 1249. 



Syme, Brit. Song Birds, p. 159. 



|| Selborne, lett. 60. 11 J. R. 



