4 BRITISH MOTHS 



in other and more essential respects, namely in the stnicturo of the mouth, wings, and especially in the trans- 

 formations of the insects composing these two Linn.-can groups, there is still less distinction between them. In 

 other words, the characters employed by Linna-us are thus proved to possess less value than he assigned to them. 

 Acting upon these considerations, Dr. Horsfield and Jlcssrs. Newman and Stephens have respectively proposed 

 plans of arrangement, in which the group Crcpuscularia is retained, and the genus Phatena divided into several 

 primary groups, each of which is regarded as equivalent in value to the Diurna ; Mr. Stephens's groups being 

 named Diurna, Crcpuscularia, Pomeridiana, Nocturna, Semidiurna, and Vespertina. My objection to these 

 arrangements is, that whilst the Diurna constitute an admirably distinct tribe, it is impossible to point out another 

 group similarly defined throughout the order. Looking for a moment at tiie Crepuscularia, or hawk-moths, as 

 thus restricted, we have antcnnje of diversified form ; flight in the hottest sunbeams as well as in the twihght ; 

 wings of varied forms and powers of flight ; proboscis much longer than the body in some, and wanting in others; 

 and transformations various ; whilst it is almost impossible to draw the line of distinction between some of the 

 Smerinthi and certain North American BombycidEB, between Urania and some of the giant Noctuidse, jEgeria and 

 the Ilepialidse, Anthrocera and some Bombycida;. It is, however, more especially amongst the exotic species 

 that we find this difliculty, whore the chain of relation between the Crepuscularia and Arctiidas, as well as other 

 tribes, is almost unbroken. Tiie same remark may be almost as fully made respecting any of the other groups 

 into which the Linnrean Bonibyccs are divided by these authors. 



I consequently consider it will be more advantageous, at least until we possess more precise materials for a 

 general classification of the order*, to unite the Linna^an Sphinges and Phalcen;e into one primary section — that 

 of the Heterocera, Boisd. — named from the diversified structure of tho antennsB, which are never terminated by 

 a club, like those of the butterflies, but are generally setaceous, filiform, or fusiform; those of the males being, 

 moreover, often furnished with more or less developed lateral, bristle-like a]>pendages forming branches ; the 

 wings are ordinarily furnished with the sprin" and socket apparatus fur retaining them together during flight ; 

 the caterpillars are extremely varied in form, colours, clothing, &c. ; but the jiuikv are generally of a conical form, 

 without angular projections, and they are ordinarily enclosed in a cocoon of varied construction, the quiescent 

 state beincr often undergone in the cround. 



3 Oft 



It will easily be conceived from the preceding remarks, that if the question of the primary divisions of the 

 Lepidoptcra be unsettled, that of the family groups cannot be better determined. As, however, the discussion of 

 these questions would occupy too great a space in the present work, I must refer the student to the second volume 

 of my Introduction to the Jlodern Classification of Insects, in which I have entered upon it at some length. 

 Admitting, as I do, my inability to offer a satisfactory distribution of the Heterocera into primary groups, I have 

 in that work proposed the following series of secondary groups or families, and which I shall adopt in the 

 folowing pages :— 1. Sphingid;e ; 2. Uraniidaj ; 3. Anthroceridaj ; 4. ^Egeriidre ; 5. llepialidif ; 6. Bombycida ; 

 7. Arctiida- (including the Notodontida; of Stephens) ; 8. Lithosiidre ; 9. Noctuidaj ; 10. Geometridaj ; 11. P\Ta- 

 lida>; 12. Tortricida' ; 13. Yponomcutidaj ; 14. Tineida;; and 15. Alucitida. The second of these families 

 consists entirely of exotic insects, and will require no further notice in the present work. 



• Mr. Svrainson well observes tliiit " so little lias been done towanls tbe pbilosopbic investigation of tliese groups, tb.it wbilst tlieir genera 

 Lave been multiplied and arc daily multiplying in tbe ailificial systems of tbe day, tbe study of tbeir affinities bas been of late years much 

 neglected." 



