34 Our Bird Friends. 



Many people think that all wild birds belonging 

 to the same species build nests exactly alike in 

 regard to style of architecture, size, materials em- 

 ployed, workmanship displayed, and situation chosen ; 

 in fact, that they are all ruled by an unerring force 

 called instinct, and that they could not depart from 

 its cast-iron laws even if they tried. Nothing could 

 be farther from the fact. Although it is quite true 

 that the little homes of birds belonoino- to the same 

 species bear a strong family resemblance by which 

 they may be readily recognised, there can be no 

 denying that the skill, industry, opportunities, and 

 oven experience and wisdom of the builder play 

 their part almost as much as they do amongst the 

 builders of human dwellings. For instance, every- 

 body easily recognises a nest built by a Song 

 Thrush, because it is deep, basin-shaped, made of 

 twigs and grass stems, lined with mud or some 

 other substance that will dry hard and smooth, and 

 is placed in some evergreen bush or hedgerow ; but 

 a close observer will notice that one Thrush's nest 

 is bigger and bulkier than another, better built, the 

 materials varied according to the builders' oppor- 

 tunities of getting them handily, and the situation 

 for it selected with fsir greater or far less wisdom. 

 Last spring I made careful measurements of two 

 Thrushs' nests Avhich I found within a very little 

 distance of each other. The first Avas situated on a 

 Hat, outspreading fir-bough, and was two inches deep 

 and four wide across the top ; the second nest Avas 



