THE DEVirS RIDING-HORSE (MANTID.E). 39 



they are developed ; the geooraphical distribution of 

 these insects, in fact, is distinguished for this trait — the 

 tendency towards Ibcahzation of the genera to the 

 different continents. In this way the distribution is very 

 clearly defined. Thus, in America the genera belong 

 for the most part exclusively to the New World, and 

 differ from those of the Old World ; and in the latter, 

 by the side of widespread genera, others are peculiar 

 to Africa, or to Asia, or to Australia, and to the 

 Isles of the Pacific. Of the genera represented in the 

 two hemispheres, their number is sufficiently restricted 

 that it may be said they are exceptions to the common 

 rule. There are the genera Ameles and Iris, found 

 both in America and in the Mediterranean regions ; 

 Liturgousa and Cardioptera appear in America and in 

 Southern Africa ; Miopteryx in America and Asia ; and 

 lastly, the American Thespis crop up in Africa and 

 in Asia in the shape of Oxythespis. It will be remarked 

 that while Ameles and Iris are of the Old World types, 

 which may have passed to America, Liturgousa, Car- 

 dioptera, and Thespis have a real American stamp, 

 and seem rather to have emigrated from America to 

 Africa, at an epoch more or less remote. 



Distinctly, America appears to possess fewer genera 

 and species than the Oriental hemisphere, and it is in 

 Asia, particularly in the Moluccas and the Isles of Sunda, 

 that the family seems to be most richly represented. 



