ANIMAL INSTINCT. 163 



birds likewise appear, and are gone, several of which, 

 however, are probably the young of ascertained species. 

 And here the little willow-wren is often to be seen : he 

 comes in company with his travelling friends, not as a 

 partaker of their plunder, appearing never to abandon 

 his appetite for insect food : the species may change 

 with the season, but still it is animal : he glides about 

 our rows of peas, peeps under the leaves of fruit trees 

 for aphides and moths, continuing this harmless pursuit 

 until the cold mornings of autumn drive him to milder 

 regions. All these fruit-eating birds seem to have a 

 very discriminating taste, and a decided preference for 

 the richest sorts the sweetest variety of the gooseberry 

 or the currant always .being selected ; and when they 

 are consumed, less saccharine dainties are submitted to: 

 but the hedge blackberry of the season our little foreign 

 connoisseurs disdain to feed on, leaving it for the hum- 

 bler appetited natives they are away to sunnier regions 

 and more grateful food. 



June 14. I was much pleased this day by detecting 

 the stratagems of a common wren to conceal its nest 

 from observation. It had formed a hollow space in the 

 thatch, on the inside of my cow-shed, in which it had 

 placed its nest by the side of a rafter, and finished it 

 with its usual neatness ; but lest the orifice of its cell 

 should engage attention, it had negligently hung a 

 ragged piece of moss on the straw-work, concealing the 

 entrance, and apparently proceeding from the rafter ; 

 and so perfect was the deception, that I should not have 

 noticed it, though tolerably observant of such things, 

 had not the bird betrayed her secret, and darted out. 

 Now from what operative cause did this stratagem pro- 

 ceed ? Habit it was not ; it seemed like an after- 

 thought ; danger was perceived, and the contrivance 

 which a contemplative being would have provided, was 

 resorted to. The limits of instinct we cannot define : * 



* I know not any definition of what we term "animal instinct " more 

 comprehensive and accordant with truth than the following, given 

 in the Elements of Etymology by Messrs. Kirby and Spence. " With- 

 out pretending to give a logical definition of it, (instinct,) which, 

 while we are ignorant of the essence of reason, is impossible, we 



