122 SOME SUGGESTIONS FOR BIRD STUDY. 



(2) Sometimes (in 24 cases) the normally- coloured 

 Cuckoo's egg resembles generally the egg of the foster bird. 

 It is, however, usually easily recognised at first sight by 

 the size. 



(3) In 12 cases extreme variants of the Cuckoo's egg 

 resemble the foster bird's eggs. This includes one blue egg 

 in a Eedstart's nest. 



(4) 65 cases are indifferent : that is, there is no notice- 

 able resemblance between the Cuckoo's egg and those of 

 the foster parent. 



The egg is laid early in the incubation period and the 

 foster parents hatch it out. The young Cuckoo early (on 

 the second day) ejects the other occupants of the nest, 

 eggs or young. The foster parents feed the intruder, con- 

 tinuing to do so sometimes to the point of sheer exhaustion, 

 so exacting are the demands of the big, black, repellent- 

 looking creature. The young Cuckoos are left behind by 

 their parents and follow them, migrating in October. 



The adult Cuckoo feeds on caterpillars, e.g. those of the 

 tiger moth and magpie moth. 



SWALLOW (S.Y.). This summer visitor is a small bird 

 of about 8 inches in length. The throat and front 

 part of head above the bill are deep rusty red ; the top of 

 head, back, and shoulders are steely blue ; quills of wings 

 and tail bluish green, but with concealed white patches on 

 inner sides of all the tail feathers except the central pair. 

 Front part of breast metallic blue, hinder parts rusty white. 

 In the female the red above the bill is less marked and the 

 breast lighter. The tail also is shorter. In the male the 

 two outer quills are prolonged about an inch and a half 

 beyond the others. The bill is short with wide gape ; the 

 feet also are short. 



The Swallow nests about buildings, under a ledge or 

 projection of some kind, sometimes in chimneys, and it is 

 said even exceptionally in the forks of trees. The nest is 

 shallow, open above, consisting of mud, straw, and feathers. 

 The eggs are 4 to 6 in number, \ to f inch in length, white, 



