370 



GEOGRAPHICAL ZOOLOGY. 



[PART iv. 



FAMILY 130. PALAPTEEYGID^. (2 Genera, 4 Species.) 



Palapteryx (2 sp.) ; Euryapteryx (2 sp.). 



These had a well-developed hind toe, and rudimentary wings. 



FAMILY 131. ^EPYORNITHHLE. (1 Genus, 3 Species.) 



A gigantic Struthious bird (^pyornis), belonging to a distinct 

 family, inhabited Madagascar. 



It was first made known by its enormous eggs, eight times 

 the bulk of those of the ostrich, which were found in a sub- 

 fossil condition. Considerable portions of skeletons have 

 since been discovered, showing that these huge birds formed 

 an altogether peculiar family of the order. 



General Remarks on the Distribution of the Struthiones. 



With the exception of the Ostrich, which has spread north- 

 ward into the Palsearctic region, the Struthious birds, living and 

 extinct, are confined to the Southern hemisphere, each continent 

 having its peculiar forms. It is a remarkable fact that the two 

 most nearly allied genera, Struthio and Rhea, should be found in 

 Africa and South Temperate America respectively. Equally re- 

 markable is the development of these large forms of wingless 

 birds in Australia and the adjacent islands, and especially in 

 New Zealand, where we have evidence which renders it probable 

 that about 20 species recently coexisted. This points to the 

 conclusion that New Zealand must, not long since, have formed 

 a much more extensive land, and that the diminution of its area 

 by subsidence has been one of the causes and perhaps the 

 main one in bringing about the extinction of many of the 

 larger species of these wingless birds. 



The wide distribution of the Struthiones may, as we have 

 already suggested (Vol. I., p. 287.), be best explained, by sup- 

 posing them to represent a very ancient type of bird, developed 

 at a time when the more specialized carnivorous mammalia had 



