VISION. 25 



branes, being probably more soft and delicate, are 

 more susceptible of impressions from a small quan- 

 tity of light. The nictitating membrane is also very 

 large, and the upper eyelid, unlike other birds, is 

 moveable*. 



We have adverted to the method of catching larks 

 by means of a looking-glass, referring to the remark- 

 able curiosity of birds as the probable cause of their 

 being attracted to the bright glass. Whether it is on 

 a similar principle that ravens, jays, and magpies 

 (Cormdas, LEACH) are fond of bright objects we have 

 no means of deciding. In accordance with this view, 

 a writer on Natural History says, " A looking-glass 

 is a matter of great wonder to magpies. We once 

 saw one placed on the ground where two were 

 hopping about. One of them came up to it, stared 

 at it in apparent wonder, hopped off to the other, 

 and then both returned and spent at least ten 

 minutes in nodding, chattering, and hopping about 

 the glass V Colonel Montagu tells us he was 

 ' assured by a gentleman of veracity, that his butler 

 having missed a great many silver spoons and other 

 articles, without being able to detect the thief for 

 some time, at last observed a tame raven with one 

 in his mouth, and watched him to his hiding-place, 

 where he found more than a dozen J. ?> 



A similar story is told by Mrs. S. C. Hall of a raven 

 kept a few years ago at Newhaven, an inn on the 

 road between Buxton and Ashbourne. This bird 

 had been taught to call the poultry when they fed, 

 and could do it very well too. One day the table 

 was set out for the coach-passengers ; the cloth was 

 laid with the knives and forks, spoons, mats, and 

 bread, and in that state was left some time, the 

 room-door being shut, but the window open. The 



* Principes d'Anatomie Comparee. 

 t Brit. Naturalist; ii. 216. $ Diet. p. 400. 



