iv VARIATION UNDER DOMESTICATION 93 



Kace VIII. Indian Frill-back. — In these birds the beak is 

 very short, and the feathers of the whole body are reversed 

 or turn backwards. 



Race IX. Jacobin. — These curious birds have a hood of 

 feathers almost enclosing the head and meeting in front of 

 the neck. The wings and tail are unusually long. 



Race X. Trumpeter. — Distinguished by a tuft of feathers 

 curling forwards over the beak, and the feet very much 

 feathered. They obtain their name from the peculiar voice 

 unlike that of any other pigeon. The coo is rapidly repeated, 

 and is continued for several minutes. The feet are covered 

 with feathers so large as often to appear like little wings. 



Race XL comprises Laughers, Frill -backs, Nuns, Spots, and 

 Swallows. — They are all very like .the common rock -pigeon, 

 but have each some slight peculiarity. The Laughers have a 

 peculiar voice, supposed to resemble a laugh. The Nuns are 

 white, with the head, tail, and primary wing-feathers black or 

 red. The Spots are white, with the tail and a spot on the 

 forehead red. The Swallows are slender, white in colour, 

 with the head and wings of some darker colour. 



Besides these races and sub-races a number of other kinds 

 have been described, and about one hundred and fifty varieties 

 can be distinguished. It is interesting to note that almost 

 every part of the bird, whose variations can be noted and 

 selected, has led to variations of a considerable extent, and 

 many of these have necessitated changes in the plumage and 

 in the skeleton quite as great as any that occur in the 

 numerous distinct species of large genera. The form of the 

 skull and beak varies enormously, so that the skulls of the 

 Short -faced tumbler and some of the Carriers differ more 

 than any wild pigeons, even those classed in distinct genera. 

 The breadth and number of the ribs vary, as well as the 

 processes on them; the number of the vertebrae and the 

 length of the sternum also vary ; and the perforations in the 

 sternum vary in size and shape. The oil gland varies in 

 development, and is sometimes absent. The number of the 

 wing-feathers varies, and those of the tail to an enormous 

 extent. The proportions of the leg and feet and the number 



