﻿OF CORYDALUS CORNUTUS. 161 



The three ocelli are arranged in a triangle, the anterior one being directed forwards, and 

 the others diagonally outwards and backwards. There is a small spine behind the eye, 

 and another larger one at the posterior angles of the head. Except the mandibles, the 

 oral organs are soft and membranaceous. They are represented by figure 8, and the 

 labrum at /. 



Sexes. — In the male (fig. 7) the antennae have about 60, and in the female 54 

 articulations, so that they are a little longer in the former sex, which has the apex of 

 the abdomen provided with two pair of forceps. The mandibles in the male are large, 

 somewhat depressed at base, tapering and arcuate, resembling horns ; they are three 

 times the length of the head, and somewhat irregular in form and direction. They are 

 round except at the apex, which is pointed, and notched so as to present a sharp, cutting 

 edge, less than a line in length. This peculiarity is not represented by M. Blanchard in 

 the new edition of the Regne Animal, pi. 104, fig. 1. That author figures the head of 

 the female on the same plate, fig. 2, and it is represented in Dr. Leidy's dissections of 

 the imago. Figure a represents the base, and a the middle portion of an antenna in the 

 male, and a" the apex in the female. 



The form and armature of the mandibles in the female resemble those of the earlier 

 stages. It is a remarkable circumstance, that sexual peculiarities as distinct as those 

 presented in the mandibles of this genus should not be conspicuous in the early stages ; 

 and the fact that these organs are essentially the same in the larva, pupa, and female 

 imago, affords an additional proof to the opinion that the female is an undeveloped con- 

 dition of the male sex. 



The earlier form of the orthography of the name, Corydahis, is preferable to that of 

 Corydalis, which is homonymous with that of a genus of plants. 



