586 FRANK E. BEDDAED. 



Fig. 11. — Three nepbridia of posterior segments on one side of body, as 

 seen on a dissection, n. Nerve-cord. Si^t. Intersegmental septum, nph. Ne- 

 phridium. /. Funnel. S. Setse of ventral pair. 



Fig. 12. — Transverse section through receptaculum ovorum and spermathe- 

 cal sac. Sp. sac. Spermathecal sac. ov. Ova. od. Oviduct, el. Elastic 

 membrane surrounding sac. 



Fig. 13. — Spermathecal sac at a later stage of development than Figs. 4 — 6, 

 illustrated by a transverse section through body-wall. Up. Epidermis, m. 

 Circular muscles, m'. Longitudinal muscles, with lymph spaces (/.). N, Ne- 

 phridial tube. Sp. sac, Sp. sac^. Two portions of spermathecal sac. Spt. 

 Intersegmental septum 12 — 13. ov. Ovary. 



Fig. 14. — Transverse section through body-wall, to show the ramifications 

 of the excretory tubes. ep. Epidermis. m. Transverse muscular layer. 

 m' , Longitudinal muscular layer. Bl. Blood-vessels. d. Longitudinal 

 nephridial vessels, d'. Smaller tubes, forming network among the muscles. 

 a. Junction with one of paired nephridia. c. Circular nephridial vessel. /. 

 Tube running to external orifice. 



Fig. 15. — Section through ventral wall of pharynx, to show opening of 

 uephridium. o. Orifice of nephridium. ner. Nerve in pharyngeal epithelium. 

 m. Muscles, nph. Nephridial tubes. 



Fig. 16. — Diagrammatic transverse section of body, to show integumental 

 nephridial network. D. v. Dorsal blood-vessel. S. I. Supra-intestinal blood- 

 vessel. /. /. Infra-intestinal vessels, v. Ventral blood-vessel. Nph. Nephri- 

 dium. /. Longitudinal trunks (four in number) of integumental network. 

 c. Circular trunk lying between circular and longitudinal muscles, a. Cir- 

 cular vessel lying beneath longitudinal muscular layer of body-wall. 



Fig. 17. — Transverse section to show perihsemal space surrounding infra- 

 oesophageal blood-vessels {Bl. vess.). ces. (Esophagus, corp. Perivisceral 

 corpuscles, mes. Walls of perihsemal space, m. Muscular bands. 



Fig. 18. — Longitudinal section through one of the three gizzards in a very 

 young specimen, giz. Epithelium of gizzard. Per. Peritoneum. Spt. 

 Septum. 



Fig. 19. — Transverse section through body-wall, more diagrammatic and 

 less highly magnified than Fig. 14. S. Setse sac. Bl. Blood-vessel. M. 

 Muscle, connecting setse of lateral and ventral couples. Coel. Ccelomic space 

 cut off from general cavity of segment by membrane Sp. N. Nephridial 

 tube. L. Longitudinal vessel of integumental nephridial network ; the net- 

 work is also indicated in white. 



Pig. 20. — Highly magnified transverse section to show circular nephridial 

 vessel («.). m. Nerve accompanying it. L. m. Longitudinal muscles. 

 t. m. Transverse muscles. 



Fig. 21. — Infra-oesophageal blood-vessels in Segments 9, 10, 11. a. Branches 

 of the same. Sp. sac. Sperm-sacs. 



