462 TROGLODYTID-E. 



roof — a fact which has been noticed by many observers. Sir 

 WilHam J-ardine says that of an evening eight or nine Wrens 

 may be seen entering one of these retreats, and, when all is 

 quiet, the hand thrust into the hole will find them huddled 

 together, surrounded by the feathers collected by the 

 Sparrows, and the degree of heat thus kept up is much 

 greater than their small bulk would at first be thought to 

 maintain. Failing such refuges they will resort to their own 

 old nests, and Selby says he has frequently found together the 

 bodies of several, which had thus sought protection and 

 warmth during severe storms. According to Herbert, also, 

 under like circumstances and for like reasons they frequently 

 roost in cow-houses. 



The Wren begins to build its nest early in spring, choos- 

 ing for the site very varied and occasionally odd spots. 

 Often, as long ago remarked by Montagu, it first traces the 

 outline of the structure by sticking bits of moss against the 

 tree, bank, wall or other place selected, probably attaching 

 them with spiders' web, and thus fastens all the parts with 

 equal strength, afterwards enclosing the sides and top, 

 and leaving only a small hole for entrance and exit. This, 

 however, is not invariably the case, and sometimes it pro- 

 ceeds from the foundation upwards, as most other birds do. 

 Mr. Weir has enriched Macgillivray's pages with a wonder- 

 fully accurate account (too long, unfortunately, to be here 

 reprinted) of the building of a Wren's nest which he dili- 

 gently watched. It was begun at 7 o'clock in the morning 

 of May 30th, and the whole external workmanship com- 

 pleted by 7 at night. During the next few days the lining 

 was carried in, and on the forenoon of June 8th the nest 

 was finished. Many writers have remarked on the adapta- 

 tion to the place of the materials used for the exterior. 

 Thus, says Montagu, if built against the side of a hayrick 

 it is composed of hay ; if against a tree covered with white 

 lichen it is studded with that material, and formed of green 

 moss if against a tree overgrown with the same. Neville 

 Wood declares that when this bird builds in a raspberry-bush 

 the whole structure is composed of the leaves of that plant. 



