60 



The Natuealist. 



Thus we see that Acentropns, though so small, has several charac- 

 teristics peculiarly its own ; yet it seems to claim a closer kin to the 

 moths than to any other class of insects. If we allow that such is 

 the case, even then only half the difQculty seems to be disposed of j 

 for where, in that vast assemblage, shall a proper place be found for 

 it ? Opinions differ, or have differed, as much on this point as on the 

 other. One person holds that the little tongueless creature should 

 belong to the tongueless group of Bombyces ; another opinionates 

 that the Cramhites^ and another that the Tineina, is the proper group 

 to which it ought to be referred ; whilst a fourth positively asserts 

 that it can be placed only in the Pyralides, along with the other moths 

 whose larvse are aquatic, and accordingly here we find it in our 

 systematic lists ; but most of the writers on the nomenclature of 

 this insect express a belief that a separate family should be set apart 

 for it, in whatever group it is placed. I am not scientific enough to 

 offer an opinion on the subject, but, considering all things, the 

 Pyralides is to me as natural a class as any in which to set it down. 

 And even with this disposal we have not arrived at the end of our 

 argument, or used up all the materials which offer themselves with 

 regard to our insect or insects, as the case may be. The moths of the 

 genus Acentropus seem to have a very extended range, as far as its 

 European habitats are concerned. France, Holland, Germany, 

 Switzerland, and parts of the Russian empire, yield specimens, and 

 yet the insects appear to be local in this and other countries. I am 

 led to believe that from its small and insignificant appearance it is 

 often overlooked, and that it will eventually be found more common 

 than is generally supposed, for its food-plants — the various species of 

 water weeds of the generic term Potamogeton — are not rare in rivers 

 where the insects have not hitherto been reported as occurring. 



In our list of British moths we have two species assigned to the 

 present genus, viz., niveus and latipennis. 1 take the insect at the 

 head of this article to be the former of the two, since we are told that 

 the females of A. latipennis found in the river Trent are apterous ; 

 yet some Continental females of what is supposed to be the same 

 species are amply winged. The specimens I take differ somewhat in 

 the form of the wings — some are more lanceolate than others ; but I 

 do not know that any specific difference is to be established therefrom, 

 as all the specimens are found together, and appear to have the same 

 habits. To Mr. Dunning's article I am indebted for much of the 

 information I have given, and he is of opinion that all the so-called 

 species, both British and Continental — (and there are ten, viz., 



