1880.] 271 



" * * * These two families (the northern crayfishes and the southern 

 crayfishes) have in common all those structural characters, which are special to 

 neither ; and carrying out the metaphorical nomenclature of the zoologist a stage 

 further, we say that the two form a Tribe — the definition of which describes the 

 plan which is common to both families." (p. 252). 



Griven a restricted group of insects of wide geographical distri- 

 bution, it would be possible to work up the subject in a similar way 

 to that which Professor Huxley has adopted iu treating of " The 

 Crayfish." 



First we are introduced to the living crayfish, till we gradually 

 seem to acquire an intimate acquaintance with it ; we watch its career 

 from its earliest development till it begins to suffer from old age ; then 

 we are treated to its anatomy, its physiology and the homologies of 

 its various segments ; next we have all its nearest I'elations pai'aded 

 before us, and necessarily therewith comes their geographical distri- 

 bution over the surface of the globe, and whilst we learn distinctly 

 where these animals do occur, we feel that the regions where none 

 have at present been observed cannot be pronounced with equal con- 

 fidence as regions in which they do not occur. For, as Professor 

 Huxley well observes, " it is always difficult to prove a negative." 



Unfortunately, no insects can expect to have their ancestry as 

 well preserved as are the fossil remains of crayfish, and the genealogy 

 of any group of insects must, therefore, remain much more involved 

 iu obscurity. 



Mountsfield, Lewisham : 



Ilarch, 1880. 



NOTES ON UNKNOWN OR LITTLE-KNOWN LARY^ OF MICRO- 



LEPIBOPTERA. 



BY E. L. RAGONOT. 



{continued /"rom p. loo). 



Scopula decrejjitalis, H.-S. 



The larva is quite unknown, the moth flies from June to August 

 in alpine countries. 



Lemiodes pulvernlis, Hb. 



The larva has been found by Herr Miihlig on Mentha aquatica, in 

 August, but it does not seem to have been described. The moth flies 

 sometimes abundantly in damp marshy localities where Mentha grows, 

 end of June and iu July. 



Stenopteryx hyhridalis, Hb. 



The larva has been described by Mr. Geo. T. Porritt in this 



