ON TEMNOOEPHALA. 301 



Fig. 2. — Longitudinal section of the ventral body wall, in the neighbour- 

 hood of the genital opening, to show the ducts of the subcutaneous glands, 



d. Other letters as above. 



Fig. 3. Cells of subcutaneous glands. 



Fig. 4. — Transverse section of a young specimen of Temuocephala 

 fasciata, in the region of the genital cloaca and penis, c. Cuticle, e. Epi- 

 dermis, b. Basement membrane. p. Pigment layer. I. m. Longitudinal 

 layer of muscle, par. Parenchyma, with subcutaneous gland-cells and dorso- 

 ventral muscular fibres, d. I. n. Dorso-lateral nerve, v. n. Ventral nerve. 

 cl. Genital cloaca, pe. Penis, vit. Lobule of vitelline gland, te. Extremity 

 of testis (here imperfectly developed). 



Fig. 5. — Outline of the alimentary canal of a young specimen of Temuo- 

 cephala fasciata. ph. Pharynx, i. Intestine. 



Fig. 6. — Vertical section of the wall of the pharynx, from a longitudinal 

 section of the body. ep. Internal layer of granular matter, i. c. I. Internal 

 circular longitudinal layer of muscle. i. c. t. Internal circular transverse 

 layer. e. c. t. External transverse. e. c. I. External longitudinal. rad. 

 Radiating fibres, g. Ganglion-cells. 



Fig. 7. Section of the wall of the intestine, m. Layer of muscle, e. Epi- 

 thelium, c. Reservoirs of granules. 



Fig. 8. — Longitudinal and vertical section of Temnocephala minor. 

 *. Sucker, v. Ventral body wall. d. Dorsal body wall. int. Cavity of the 

 intestine, sept. Septa, vit. Lobules of vitelline gland, gl. Subcutaneous 

 gland-cells, od. Oviduct, ut. Uterus, rec. Receptaculum seminis. 



Fig. 9. — Excretory sac of Temnocephala fasciata in the fresh condi- 

 dition, viewed from the dorsal aspect, o. External opening. /. c. Longitudinal 

 canals, g. Nuclei of ganglion-cells. 



Fig. 10. — Section of excretory sac, on a level with the external opening. 



e. Proper wall of sac, with vacuoles, in. Investing layer of muscle, g. 

 Ganglion-cell. 



Fig. 11. — Longitudinal section of posterior excretory canal. 



Fig. 12. — Diagram of dorsal portion of nervous system, showing the arrange- 

 ment of the tentacular nerves, and the dorsal longitudinal trunks with their 

 branches and commissures. 



Fig. 13.— Transverse section through the eyes of Temnocephala fasci- 

 ata. p. Pigment cup. r. Contained substance, g. Ganglion-cells opposite the 

 mouth of the cup. t. Peculiar cell enclosed in the pigment of the optic cup. 

 ii. Large cells lying between the eyes. 



VOL. XXVIII, PART 2. NEW SEN.. 



