26 Trans. Acad. Sci. of St. Louis 



make interesting, charming pets, for the Shrikes are 

 intelligent birds with a comparatively large brain. How- 

 ever, they are quarrelsome and envious, and when two 

 are kept in one cage it will not be long before one of them 

 is killed by the other. Shrikes require much food, and 

 it is for this reason that they are not sociable, prefer a 

 solitary life and drive intruders from their chosen 

 domain. Although belonging to the Oscine Passerine 

 birds. Shrikes are generally not classed among singing 

 birds, but they have a melodious song, though not loud 

 and only given when they believe themselves not heard 

 by man. It was only when I was entirely out of his sight 

 that my pet indulged in his vocal practices, soft and 

 really pleasing performances. Much can be learned from 

 birds kept in confinement. 



One grand dominating impulse of migration in spring 

 is breeding, to insure the perpetuation of the species. 

 Migratory birds come north to breed, to rear their young 

 in a climate where the temperature is best suited to their 

 requirements. Another physiological process tells them 

 when to leave their summer homes. The failure of food 

 supply is undoubtedly the most important impulse, but 

 this southern flight has been performed so often and so 

 regularly that the impulse has become hereditary as is 

 demonstrated by many facts. My pet Shrike was in a 

 dark room where no noise such as the calls of migrants 

 passing over could reach him, the room was warm and 

 the food plentiful, but when October came along every 

 evening about nine o 'clock he began to flutter in his cage 

 and thrust himself against the wires until quite ex- 

 hausted. This migratory instinct forces most birds to 

 leave their breeding grounds long before real want of 

 food is felt, often at a time when nothing indicates the 

 approach of winter. Many insect-eating birds leave in 

 August and September when insects are most abundant ; 

 seed and fruit eaters depart when there is still an 



