IJ8 CAMFORNIA ACADEMY OF SCIENCES. 



PLATE XXXIII. 



PHffiNICODEILUS TASTE. 

 17. Longitudinal section of the alimentary canal (cesophagns), in vi. ep. inner lining epithelium, yl. glandular 



cells, hi. blood sinus, m. the two muscular layers, pt. peritoneal epithelium. 

 IS. Longitudinal section of the pharynx, showing the glandular ducts and ductules penetrating the pharyngeal 



epithelium, d. ciliated surface, n. ep. nuclei of epithelium. rf«.s. ductules, duct, large duct from the 



pharyngeal glands above the oesophagus, ce. ep. oesophageal epithelium joining the pharyngeal ciliated 



epithelium. 



19. Section of the Viody through one of the clitellar somites, a diagrammatic view, to show the relative size of the 



dift'ereut layers of the body-wall. d. i\ dorsal vessel, s. /. saculated intestine, m. I. the muscular layers. 

 cl. c. clitellar cells, sp. d. spermducts. v. v and n. e. ventral vessel and nerve cord. 



20. A diagrammatic section of the body in somite ix showing the relative size, etc., of the diverticula and the 



layers of the body-wall. d. v. dorsal vessel, sp. s. sperm-sacs in somites ix and x. die. diverticula of the 

 intestine, v. v. ventral vessel, n. c. nerve cord. 



21. Section of body-wall of a non-clitellar somite. ;/. r. unicellular glands. .«. c. supporting cells. I. m. trans- 



verse muscular layer. I. m. longitudinal muscular layer, pr. peritoneum. 



KERRIA McDONALDI. 



2.'?. Nephridium of Kerria ilcDonaldi from one of the somites closely posterior to the clitellum. 7»-. .s. peritoneal 

 sac with nuclei. The posterior end of this sac is not furnished with blood capillaries, c. hi. capillary blood 

 vessels, spreading principally through the peritoneal sac. a. I. anterior lobe. p. I. posterior lobe, nephr. st. 

 uephrostome. nephr. pr. nephropore. w. d. wide duct outlet. «. d. n.arrow duct. nee. neck of the 

 nephridium, hi\ bridge, spr. spur. .«. septum, 



PONTODKLLUS MICHAELSENI. 



24. A specimen, natural size, having been slowly killed and extended. One of the largest specimens, the majority 



being only one-half as large. 



25. The three anterior somites seen from the side. /)r. prostomium. per. peristomium. 



26. The anterior part of the worm more highlj' magnified, ventral view. cl. clitellum. S male pore. spth. p. 



spermathecal pores, ov.p. ovipore. c.pr.m. cushion where euds the fan-shaped fascicle of prostate or arci- 

 form muscles, c. c. exterior copulatory cushion. 



27. Part of the body-wall laid opeu and spread out to show the relative distances of the seta?, the numerals 



indicating the number of the seta. The ventral nerve cord is indicated. 



28. One of the setiB highly magnified. 



