33 



of a large Cuckoo to that of a Turkey. They are arboreal and 

 nest in trees. Some are curiously crested and helmeted (see 

 Case I). 



Order XVT, Pterocletes, is a small group, embracing the Sand- 

 Grouse, which curiously combine some of the characteristics of 

 Pigeons with others strongly suggestive of the Grouse and Plovers. 

 They number about twenty species, all Old World (see Case P). 

 They constitute the two genera Pteroclcs and Syrrhaptes. 



Order XVII, Columbce^ the Pigeons, includes several families, 

 only one of which occurs in America. The first, Didiihe, is repre- 

 sented by only two species, both of which are extinct — the famous 

 Dodo {Didiis iiicptus)^ and the Solitaire {Fczop/urps solitaria). Both 

 were large ungainly birds, with wings too small for flight. Their 

 affinities were for a long time in doubt, but naturalists now agree 

 in giving them a place in the order of Pigeons. They formerly 

 inhabited the islands of Rodriguez and Mauritius, the Dodo being 

 also found in the Isle of Bourbon. The Dutch navigators found 

 them numerous when they first visited these islands early in the 

 seventeenth century, but they were exterminated about the end of 

 that century. They are known only from two or three paintings 

 and from their bones, discovered principally in the swamps of 

 Mauritius. A part of a skeleton may be seen in Case T of the 

 Geological Hall. 



The family DidunciiUdie is also a small group, consisting of a 

 single species, the Tooth-billed Pigeon {Didu/iculiis stn'i^irostris), 

 inhabiting the Samoan Islands. (Case P.) 



The Crowned Pigeons (family Goun'dce) are ground Pigeons ; 

 they are birds of large size, with high open crests, and striking 

 appearance (see Case P). Only about six species are known, 

 confined to New Guinea and some of the neighboring Papuan 

 Islands. 



The true Pigeons and Doves (family Columbidce) are repre- 

 sented in all countries, though most numerous in the subtropical 

 and tropical regions. Nearly three hundred species are recog- 

 nized, of which about ninety are American, but only about a 

 dozen are found in the United States (see Case C). They vary 



I 



