On the Antennce and Trophi of Lepidopterous Larvce. .9 



the mandibles of Lithocolletis of the flat group, in the first and second 

 forms ; figs. 32 and 33 those of the cylindrical group of the same genus. 

 When reference is made herein to the " first form, " and the "second ' 

 or "ordinary form," it is to forms like these. In all of the pupae of spe- 

 cies which leave the egg with larvae of the first form, the anal hooklets 

 by which the pupa is anchored in its cocoon are lateral instead of ter" 

 minal; that is, they are placed on the sides of the anal segment instead 

 of at its apex. These pupae also have the head beaked in front, and 

 numerous serrations on each side of the beak in some genera. But 

 this armature of the head is not peculiar to species which are 

 known to leave the egg with the first form of trophi. Since Pronuba-, 

 Prodoxus, the pupae of the clearwings, and some other pupae, also have 

 the head beaked, and Bedellia somnutentella has the beak of a remark- 

 able size, and it certainly never has trophi of the first form. Prof- 

 Comstock, in his valuable Report as Entomologist of the Agricultural 

 Department, has many interesting observations on larvae and pupae 

 of Lithocolletis, and seems to consider this armature of the head and 

 anal segment as especially adapted to the uses of the insect in making 

 its exit from the mine, and certainly it does answer a very useful pur_ 

 pose in that way; but whether it has been especially developed for 

 that purpose by the conditions of existence, or in an}' other way, will 

 at least admit of doubt. The pupae of Lithocolletis ornatella^ and 

 Leucanthiza amphicarpecefoliella, and nearly all species of Gracillaria, 

 Ornix and Coriscium leave their mines before pupating, and pupate in 

 little cocoons, and need these anal and cephalic structures no more than 

 any other insect which pupates in a cocoon. Bedellia somnutentella does 

 not even leave anything that ma}? be called a coccoon, but pupates simply 

 suspended in a silken web (recalling somewhat to mind the pupae of 

 Lyonetia). Pronuba yuccasella pupates underground: yet all of these 

 have the capital beak, and the Gracillaria have also the lateral arma- 

 ture of the anal segment, and no good reason is seen why these genera 

 should possess these structures any more than the thousands of other 

 pupae which inhabit cocoons, and are destitute of such armature. On 

 the other hand, the pupae of various species of Laverna, Tischeria, and 

 countless others which live in mines or in stems, or like Cemiostoma 

 or Nepticula, simply in cocoons, have the heads round and blunt, with- 

 out beak or serrations, and the anal armature at the apex of the abdo- 

 men, as is usual in moths and butterflies, and structures like those of 

 Lithocolletis, Gracillaria, etc., would certainly be as useful to Laverna 

 gleditschiaiella in piercing the tough hard cuticle of a gleditischia thorn 



