772 Mr. W. P. Pycraft 07i the 



and Alectoropod members of the Galli and the peculiarities 

 of tlieir distribution. But, while demoDstratiug the intimate 

 relationship between the Old \Yorld Megapodidse and the 

 New World Cracidse, he made no attempt to account for 

 their geographical isolation. 



The clue to this problem is apparently furnished by the 

 African Numididae^ which are to be regarded as the nearest 

 living representatives of the ancestral Galline stock. About 

 this there can be little doubt^ for they present many features 

 in common with the Phasianidae and Tetraonidse, on the one 

 hand, and with the Cracidae and Megapodidae, on the other. 



That this stock had its birth within the African conti- 

 nent, and that its main types were evolved and distributed 

 over the areas they now occupy, at least approximately, 

 during the Paleocene epoch, is a conclusion which seems 

 justified by the discovery of the remains of a small gene- 

 ralized form, Gallinuloides, in the Eocene Green River 

 formations of Wyoming — that is to say, in a later deposit 

 than the Paleocene, and answering to the lower Eocene of 

 European palaeontologists ; while the genera Palaortyx, 

 Taoperdix, and Tetrao occur in the upper Eocene of France. 

 Coiurnix, again, dates back to the Eocene, while Phasianus, 

 so far, has not been met with earlier than the Miocene of 

 France. Finally, in this connection, it is certainly signi- 

 ficant that one of the most aberrant members of the Galli- 

 formes, Opisthocumus , now confined to north-eastern South 

 America, should be represented by a closely-allied form, 

 Filholornis, in the upper Eocene of southern France. 



The South-American continent contains a greater assem- 

 blage of primitive Gruiformes than any other region of the 

 world ; yet no attempt has so far been made to discover 

 what light these may throw on the problem of ancient land- 

 connections. Briefly, of five sharply-differentiated families — 

 Cariamidae, Psophiidae, Heliornithidae, Eurypygidae, and 

 Aramidse — only two are represented in Central America, 

 and only one (the Heliornithidse) is met with in the Old 

 World. The ancestors of these autochthonous types are 



