THE SWIMMING ICHNEUMON PLY. 263 



The generic name, Polynema, refers to this pecu- 

 liarity. It is formed from two Greek words, the 

 former of which signifies " many/' and the latter, a 

 thread or filament. Some of these hairs or bristles 

 are even longer than the breadth of the wing. There 

 is a closely -allied species, Mymar pulchellus, in which 

 these hairs or bristles are more than twice as long as 

 the wing is wide. 



The writer also calls attention to the very imperfect 

 state of our entomological knowledge. The order oi 

 the Hymenoptera is one of the most popular and best 

 studied in all entomology, inasmuch as in it we have 

 the best workers, and most interesting species that 

 are as yet known to the world. The bees, wasps, and 

 ants are proverbial for their industry and the wonderful 

 structures which they erect ; while the Ichneumons are 

 equally interesting on account of their parasitic habits. 

 Yet, here is an indigenous Ichneumon which escaped 

 observers for many years, and at last was only found, 

 as it were, by chance. 



Another point which is to be considered, is the 

 object for which the Polynema enters the water. The 

 obvious reply to such a query is, that it does so for 

 the purpose of meeting with subaquatic insects in 

 which to deposit its eggs. There are, however, two 

 objections to the theory, either of which seems fatal ; 

 the first being, that the male enters the water as freely 

 as the female ; and the second, that the larvae of all 

 known Hymenoptera breathe atmospheric air, and 

 could not exist beneath the water. 



