THE ENTOMOLOGIST. 113 



character, is said by all observers to be similar to tliat of 

 Catocala, Drasteria, and olher Heterocera, viz., deflexed or 

 incumbent. Yuccae, both in manner of repose, in colour, and 

 in pattern, is a staunch Hesperian. 



In short, a careful consideration of the characters of our 

 yucca borer shows that in all the more important characters 

 it is essentially Hesperian; and that in most of those characters 

 by which it differs from the more typical species of that family 

 — as in the small spurs, in having only the apical ones on the 

 hind tibia?, in the tibial spines, and difference in size of legs 

 — it is more Rhopalocerous than Heterocerous. The same 

 holds true when we consider the adolescent states. In the 

 small head of both larva and imago, and in the very large 

 abdomen, it is abnormal ; but these characters are traceable 

 to the abnormal larval habit, and are very unimportant 

 compared to the pterogostic and other characters cited. I 

 have long since concluded that general larval form and 

 appearance is so dependent on habit and so variable according 

 to habit, that it is less valuable than more minute structural 

 characters, and that for purposes of classification it has even 

 less value than egg-structure, and infinitely less than imaginal 

 characters. AW endophytous Lepidopterous larva', of what- 

 ever family, have certain general resemblances that are a 

 consequence of similarity of habit ; and I give it as my 

 emphatic opinion that Yucca? is a large-bodied Hesperian, 

 which, though approaching the Caslnians through Synemon, 

 has no real relation with ihem. In certain marked characters 

 it departs from the Hesperians as at present understood, and 

 the only question which a careful study of the species gives 

 rise to in my mind is — not whether it should be considered a 

 Castnian, but whether it ofTers characters that necessarily 

 separate it from the Hesperians. Families should, I think, 

 be made as comprehensive as possible and not unduly 

 muliiplied ; and in considering aberrant forms, the objects of 

 classification are best subserved by retaining them in what- 

 ever division can claim the balance of characters. It is better 

 to widen than to restrict in the higher groups. LeConle does 

 better service in bringing Platypsylla among the Coleoptera 

 than does Westwood in creating a new Order — Achreiopiera 

 — for it. Phylloxera, in Homoptera, is much more wisely 

 retained in the A])hididaj than made the type of a new Family. 



Q 



