3tljB IrtBlj Jiaturalist, 



VOLUME XXXII. 



THE SLEEPING HABITS OF THE 

 TREE-CREEPER. 



BY NEVIN H. FOSTER, F.L.S., M.R.I.A. 



PLATE I. 



A SHORT time ago, Mr. A. C. Da vies of Lenaderg, Co. Down, 

 informed me that he had been observing the sleeping 

 habits of the Tree-Creeper, Certhia familiar is, in his 

 neighbourhood. His observations showed that these birds 

 excavated holes in the bark of Sequoia (Wellingtonia) 

 gigantea into which they crept at nightfall and there 

 spent the hours of darkness, their backs being approximately 

 on a level with the surface of the tree's bark, and their 

 beaks pointing straight upwards. Presumably the birds 

 take hold with the claws of their feet, and are assisted 

 in maintaining their position by means of the distal ends 

 of the stiff tail feathers being pressed against the bark, 

 as obtains when these birds are climbing tree-trunks or 

 branches in pursuit of food. The bark of this tree is soft 

 and fibrous in texture, and hence it proves a task of Httle 

 difficulty for the birds to excavate these sleeping-chambers. 

 An examination of some twenty trees of this species 

 which are growing here (all situate in an area of about 

 8 acres, the distance between the two furthest apart being 



