524 



ME. A. D. MICHAEL ON THE 



EXPLANATION OF THE PLATES. 



Lettering. 



A. Anus (so called) . This is really the orifice 



for the discharge of the excretory organs 

 only, not apparently of the alimentary 

 canal. 

 ac. Air-chamher of respiratory system. 

 acg. Air-chamber in genital organs of male. 

 acp. Passage from acy to the outer part of the 

 penial canal. 

 as. Amphioid sclerite of penial canal. 



B. Chitinous bar at the rear of the roof of the 



rostrum. Henkiu's " Chitinbriicke." 

 bh. Brushes of hair or spines inside penial 



canal. 

 br. Brain. 



C. Cuticle. 



C(S. Anterior cieca of ventriculus. 

 cap. Posterior caeca of ventriculus. 

 cas. Caecum of tubixlar salivary gland. 

 ct. Connective tissue. 



cu. Cuneiform chamber of reniform salivary 

 gland. 



D. Common duct of three of the salivary glands, 



viz., the tubular, the reniform, and the 



anterior. 

 da. Duct from the anterior salivary gland. 

 dp. Duct from the pericibal salivary gland. 

 dr. Duct from the reniform salivary gland. 

 dsa. Duct from the azygous salivary gland. 



E. Excretory organ. 



el. External labia of genital organs. 

 eph. Epipharynx. 

 es. Embedding-sac of male genital organs. 

 ew. Excretoiy (urinary) white matter. 

 fg. Food-globules absorbed and lying within 

 the cells of the ventriculus. 

 gaa. Azygous accessory gland of male genital 

 organs. 

 gl. Laminated gland of male genital organs. 

 gin. Glandulaj mucoste (the great mucous 

 glands) ; probably modified vasa deferentia. 

 gso. Supra-oesophageal ganglion (upper part of 



brain). 

 gsu. Sub-ffisophageal ganglion (under part of 

 brain) . 

 H. Hypoderm. 



hm. 



hp. 



K. 



La. 



Ian. 



le. 



U. 



mc. 



mcr. 



md. 



mda. 



VI dl. 



me. 



mf. 



mfp. 



ml. 

 mlp. 



mop. 



m,p. 



mr. 

 mrp. 



n\. 



n'2. 



71 3. 



n 4. 

 na 1. 



nu )i. 



na 3. 



na 4. 



nus. 



nb. 



nc. 



Half-moon-shaped spiked membrane of epi- 

 pharynx. 



Hamuli (hooks) of the membranous lobes of 

 the central tube of the penial canal. 



Entrance from the mucous gland to the 

 testicular bridge. 



Labia closing the duct from ,the azygous 

 salivary gland. 



Labia ani. 



External labia of genital aperture. 



Lingua. 



Constrictor muscles of penial canal. 



Constrictor muscles of receptaculum cibi. 



Mandibles. 



Divaricator muscles of the labia ani. 



Divaricator muscles of the labia which close 

 the duct from the azygous accessory gland 

 of the male genital organs. 



Dorso-ventral muscles. 



Membranous flaps at the distal end of the 

 maxillary lip. 



Membranous flaps at the end of the central 

 tube of the penial canal. 



Maxillary lip. 



Levator muscles of the roof of the pharynx 

 (dilatores pharyngis) . 



Occlusor (constrictor) muscles of the pha- 

 rynx. 



Partition between the mandibles. 



Anterior retractor muscles of penial canal. 



Posterior retractor muscles of penial canal. 



Nerve to first leg. 



Nerve to second leg. 



Nerve to third leg. 



Nerve to fourth leg. 



The branch of the nerve of the first leg 

 which is the honiologue of the accessory 

 nerve of Croneberg, Schaub, Nalepa, &c. 



The like of the second leg. 



The like of the third leg. 



The like of the fourth leg. 



Second accessory nerve of fourth leg. 



Posterior branch of the fourth leg-nei've. 



Branch of the pharyngeal nerve going to 

 the receptaculum cibi (sucking-stomach) . 



