244 



MONOGRAPH OF TIIE LABOULBENIACE.E. 



Hosts of Laboulbeniace.e. According to our present knowledge all members 

 of the family are entomogenous, and occur only upon members of the orders Cole- 

 optera, Diptera, and Neuroptera, with a single instance found among the Arachnida. 

 Peyritsch in his third paper refers to an observation recorded by Hagen, where 

 he does not state, of the occurrence of a member of the family on one of the 

 Orthoptera ; and although this must be considered of doubtful authenticity, it seems 

 more than probable that others of the insect orders, especially the Hymenoptera, may 

 prove to be similarly parasitized. It will be noticed in the appended host index that 

 coleopterous hosts outnumber very greatly all others ; yet it should be borne in mind 

 that this predominance of beetles in the list may be due in part to the fact that no 

 other group has been examined with any care in this connection. The known occur- 

 rence of species on such diverse insects as the delicate fly Drosophila, the larva of a 

 white ant, and the acarid Antennophorus, certainly suggests many possibilities as to the 

 types of hosts likely to be affected. There seems no good reason, then, why a much 

 greater variety of insects than are at present known should not be added to the list, 

 especially from the tropics, provided that they fulfil the apparent requirement of over- 

 lapping generations and moderate longevity, coupled with a cleanly and not too 

 solitary habit. 



The relative numbers infesting the various orders and families of insects may be 

 seen at a glance from the following table, which includes all forms known to the 

 writer, whether described or otherwise, and is approximately correct, though not abso- 

 lutely so, in so far as regards the number of the undetermined species of hosts. 



Table of Host Insects of Laboulbeniace^;. 



Total number of species of insects known to become the hosts of members of the Laboul- 



beniaceae 250 



Total number of genera represented by these hosts 86 



Total number of hosts belonging to the order Coleoptera 241 



Total numbers of hosts in the different families of this order: — 







47; 



species, 



156 





u 



2 



u 



2 





a 



3 



a 



8 





K 



3 



a 



15 





it 



4 



a 



9 





« 



18 



u 



50 







1 



a 



1 



Total number of hosts belonging to the order Diptera 



6 



