MORPHOLOGY OF THE LEPIDOPTERA. 167 



of pupal life was distant 2 millim. from the bursal aperture, and 1-7 millim. from the 

 oviducal as measured approximately. At this stage it is about 175 millim. distant from 

 the former, whilst, as just stated, it is now immediately behind the latter. 



A dissection from a specimen slightly older than the one from which the sections 

 were prepared is figured PL XIX. fig. 73. It shows the rectum (>•) above, the 

 oviducal aperture (o.ap.) in the middle, and the odoriferous glands (od.gl.) below, and 

 the infoldings of hypodermis (J]f) surrounding them. The distance from side to side 

 measured from the apex or ridge of one to the other fold is "75 millim. approximately, 

 and in a vertical direction from just above the rectum to the common base of the 

 odoriferous glands about the same amount. The terminal papilla, which is represented 

 by the area inclosed by the folds, consequently occupies but a small portion of the whole 

 area of the tenth somite of the pupa. In this somite the vertical distance from the 

 base of the cremaster to the spot where the ninth sternum ends between the sustentor 

 ridges is 2-45 millim., and from the ridge of one sustentor to the ridge of the other at 

 the spot where they are widest apart, 2 - l millim. These facts speak for themselves. 



The only other points to be mentioned are the following : — (1) The paired oviducts 

 are now very short, have increased in diameter, and their lumina are of considerable size 

 (PL XIX. fig. 63). (2) The tubular duct connecting the sebaceous vesicles to the 

 azygos oviduct takes now, as it does in the imago, a decidedly backward course. (3) 

 There is a very well developed and thick coat of minute cells surrounding the median 

 and posterior portions of the azygos oviduct, and the coagulable fluid (?) mentioned 

 before (p. 166) is much increased in amount, and may be seen here and there imbedding 

 the growing scales, and drawn out into irregular bands and filaments by the separation 

 of the pupal cuticle from the hypodermis (PL XIX. figs. 72, 77, cu.l.). 



The formation of the terminal papilla of the abdomen is the last feature requisite to 

 complete the developmental history dealt with in the present paper. The generative 

 organs have by this time almost assumed the proportions they possess in the imago. 

 There is a slight further growth in size, but the final histological differentiation of the 

 organs has scarcely commenced. It is not my purpose, however, to enter here into a 

 detailed investigation of changes of the latter kind. 



Summary of Results. 



§ 1. The External Anatomical Characters distinctive of Sex in the Chrysalis. 



1. The male chrysalis is characterized by a linear depression in the ninth sternal 

 ;gion. 



2. The female chrysalis is characterized in one of the following ways : — 



(i.) By two linear depressions, one in the eighth, sternal region, the other in the 



ninth, 

 (ii.) By a longitudinal furrow crossing the posterior third of the eighth sternal 



region, and a similar complete furrow crossing the ninth. 



SECOND SERIES. — ZOOLOGY, VOL. V. 26 



