268 HISTORY OF THE EUROPEAN FAUNA. 



ties, they even occasionally gnaw at the pupae and 

 larvae of the ant with which they live. 



Such beetles naturally can only have extremely 

 limited means of distribution, and they are com- 

 parable in that respect with the woodlice of the genus 

 Platyarthrus, to which I have already had occasion 

 to refer. All the species of Claviger are confined to 

 Europe, chiefly to the south, but one species, CL 

 testaceus, has wandered farther north and occurs in 

 the nest of the ant Lasius flavus in the south of 

 England, Ireland, and Scotland. Though none of the 

 Clavigers can be claimed as Oriental migrants, the 

 centre of distribution of the genera belonging to the 

 Clavigerida is in Southern Asia, and it is probable 

 that the ancestors of the European Clavigers have 

 spread westward from that region to Europe, eastward 

 to Australia and Japan, and southward to Madagascar 

 and South Africa. The genus Hopatroides, belonging 

 to the same family as the so-called Spanish-fly (Tene- 

 brionidcz}) has twelve species in Western Asia and 

 Greece. One only, H. thoracicus an instance of dis- 

 continuous distribution occurs in Andalusia. Amphi- 

 coma is represented in Western Asia and the Balkan 

 peninsula by fifteen species, while three others are 

 met with in North-west Africa and Southern Spain. 



A genus of Dragon - fly, Onychogomphus y has in 

 Europe a somewhat similar distribution to Claviger, 

 but it has besides a very extensive foreign range. 

 There are altogether thirty-five species ; of these ten 

 are Holarctic, twelve Oriental, five Mascarene, and 



