﻿168 INTERNAL ANATOMY OF CORYDALUS CORNUTUS. 



and transparent superimposed laminae. The optic nerve, on reaching the base of the 

 simple eyes, sends off as many cylinders, each of which passes outwardly to meet a 

 corresponding projecting cornea. Each cylinder of the optic nerve and the inner pro- 

 jecting part of the cornea form a cylinder surrounded by the membrana choroidea, 

 which latter passes a short distance between the nerve and cornea, forming a sort of iris. 



Explanation of the Figures. 



Plate II. — Principally exhibits the digestive apparatus of Corydalus cornutus. 



Fig. 1. Represents the digestive apparatus of the larva, magnified two diameters : — a. oesophagus ; b. pro- 

 ventriculus ; c. ventriculus ; d. large intestine ; e. biliary vessels ; f. urinary sac ; g. testicle or ovary. 



Fig. 2. The digestive apparatus of the pupa (male), magnified two diameters: — a. oesophagus; b. crop 

 or proventriculus ; c. ventriculus ; d. cceca of ventriculus ; e. large intestine ; f. biliary vessels ; g. uri- 

 nary sac ; h. testicle ; i. vas deferens. 



Fig. 3. The organs of digestion of the imago in situ, magnified two diameters : — a. oesophagus ; b. pro- 

 ventriculus; c. cceca of the ventriculus; d. large intestine; e. ccecum of the large intestine, much dis- 

 tended and exhibiting its two rows of glands ; f. rectum ; g. urinary sac ; h. main tracheal trunk, dividing 

 into two large branches passing to the thorax and head ; i. dorsal vessel. 



Fig. 4. The lower portion of the alimentary canal of the imago, dissected out, magnified two diameters : — 

 a. proventriculus; b. coecum of proventriculus; c. ventriculus; d. cceca of the ventriculus; e. large in- 

 testine ; f. ccecum ; g. rectum ; h. biliary vessels turned forwards ; i. urinary sac. 



Fig. 5. The same as fig. 4, from another individual, in which the parts were more contracted. 



Fig. 6. The proventriculus of the larva laid open to its inner surface, magnified : — a. folds of the mucous 

 membrane of the lower part of the oesophagus ; b. muscular columns of the proventriculus ; c. stomachal 

 teeth. 



Fig. 7. Front view of one of the muscular columns and teeth of the proventriculus, highly magnified. 



Fig. 8. Side view of fig. 7. 

 Plate III. — Principally represents the nervous system and generative apparatus of Corydalus cornutus. 



Fig. 1. The nervous system of the imago, magnified three diameters : — a. cerebrum ; b. cerebellum ; c. the 

 three thoracic ganglia ; d. abdominal ganglia. 



Fig. 2. Two fragments of the eye of the larva, highly magnified, exhibiting the internal appearance of the 

 conical projecting cornules. 



Fig. 3. A longitudinal section of a cornule, highly magnified and exhibiting its laminated structure. 



Fig. 4. An ideal section of one of the simple eyes of the larva, presenting the cornule projecting inwards, 

 a ; the optic nerve outwards, b ; and the choroidea folding around the projecting portions, c. 



Fig. 5. Testes of imago, magnified two diameters. 



Fig. 6. Dorso-lateral view of the termination of the abdomen of the male imago, magnified two diameters, 

 exhibiting the four prehensile hooks for attachment to the female. 



Fig. 7. Ventral view of fig. 6: — a. generative aperture. 



Fig. 8. Same view of the termination of the abdomen of the female : — a. generative aperture. 



Fig. 9. Generative apparatus of the female, magnified two diameters: — a. ovary; b. oviduct; c. vagina. 



Fig. 10. A single ovigerous tube, magnified six diameters. 



