PEDIGREES AND FAMILY TIES. * 213 



that of the ratite, from the absence of the keel^ 

 looks like a raft. 



A much more important character for the pur- 

 pose of tracing relationships is the method of 

 arrangement of the bones of the palate. 



The long since extinct yEpyo7^nis, and the moa, 

 measured by this test are seen to be related one to 

 another, and to the living emu of to-day. More- 

 over these and the tinamous can on this account 

 be separated from all other living birds. 



The number of the toes varies. In the jEpyorniSy 

 the moa and the apteryx, there are four — a hind- 

 toe and three front ones. In the cassowary, emu, 

 and rhea, there are only three, the hind-toe being 

 absent. In the ostrich there are only two, re- 

 presenting the third and fourth. In the young 

 ostrich the second metatarsal bone, for the sup- 

 port of the second but missing toe, is present ;. 

 but all trace of its distinctness is lost later, and 

 it helps to form the common shaft of the leg. 

 The toe is never developed. There are other 

 anatomical points which show that these birds 

 are related, but they need not be dealt with 

 here. 



The tinamou, a South American game-bird, is 

 apparently somewhat closely related to the rhea 

 of the same region. The arrangement of the 

 bones of the palate is precisely similar. The hip- 

 girdle is also of the same type. The down which 

 clothes the nestling is however quite different, 

 differing indeed from that of any other bird. 



Here we come to another break. It is im- 

 possible to do more than guess at the next 

 nearest allies of the "ratitae." The game-birds 



