34 DR. BRACKENRIDGE CLEMENS' LETTERS. 



insects, after having tested its value in my own studies. All 

 the groups are rigidly exclusive, and you would be gratified, 

 I think, could you see how much systemization is facilitated 

 by the use of it, however much you might object to the 

 principal groups which are formed in it. I will give these, 

 and they will indicate, at the same time, my conceptions re- 

 specting classification. The future study of our fauna may, 

 however, modify my conceptions, but I cannot here specify 

 in what particulars. 



In the first place, then, I am much inclined to include the 

 Tor trices in the group TINEINA, as one of its family groups. 

 I will not detail here my reasons for this, but of one thing I 

 am certainly convinced, that Mr. Wilkinson's division of the 

 group into families, representing I suppose the European 

 practice in this respect, is purely artificial and unmeaning in 

 so far as any definite conception is connected with them. 

 They are merely convenient groupings of genera intended to 

 facilitate the recognition of these groups. This object can be 

 attained in a manner less objectionable. 



With respect to the Tineina proper, to give you a tabular 

 statement of my ideas, I would arrange the group in the 

 following manner ; but I ought to premise that this is merely 

 an abstract of the principal groups in the Table, and they 

 are not as distinctly characterized as they are there. 



TINEID^E. Hind-wings rather broad, frequently somewhat 



narrow and ovate-lanceolate, never linear-lanceolate. 

 Group. I. Micropterigides. Neuration of both wings 



nearly alike. 



Group II. Tineides. Median vein of h. w. two-branched ; 

 subcostal simple or bifid ; discal nervules two or three, 

 distinct; often rather narrow and ovate-lanceolate. 

 Group. III. Gelechides. Median of hind-wings three- 

 branched; very frequently the medio-posterior and 

 central nervules are placed on a common stalk ; sub- 

 costal simple or bifid ; discal nervules are two, one or 

 none. 



