94 CALIKOK.NIA AfADK.MV UF SCIENCES. 



PLATE XXXI. 



PHCENICUDRILUS TASTE. 



.5. A transverse seotinu of thr body-wiill iu souiite xvii, through the male pore showing the degenerated atrium 

 and the wider upper piirt where enters the spermduct. These latter have just Vjeeu fused and enter the pore 

 as one siugle duet. <(. clitellar cells, hij. hypodcrmal layer, cl. collar of epithelium of the atrial ehaiuher. 

 rtc m. aroiform muscles. /. »;>. fused sperniduet just eutcriiig the atrial chamber. /. m. longitudinal mus- 

 cular layer of body-wall. tr. m. transverse muscular layer of body-wall. '. male pore. 



G.\. The section nearest anterior to the former, showing the spermducts just as they enter the atrial chamber. 

 The spermducts are not yet fused. Figures indicate the same as in the preceding figure. »;). spermducts just 

 before being fused together. 



6H. Section nearest anterior to the former showing the two spermducts, etc. 



7. The three somites xvi, xvii and xviii viewed from the interior, the alimentary canal and nerve-cord having been 



removed, as well as nephridia. 



8. One of the setaa magnified, the same relative proi)orlluu as that usid in my piii)er on Oinemdrilus. 



9.\. One of the uephrostomes seen in front views. When in proper position the face of the rosette stands 

 parallel to the septum, r. rosette proper, n. neck with very large glandular cells, h. </. narrow duct. 

 a. septum. /. fold of the main nephridial body. 



!)B. Nephrostome seen from the side, the position when the body is opened and spread out. Letters indicate the 

 same as in the last figure. 



10. O:io of the muscles connecting septal glands with body-wall, in cross-section, .s. sci)tum. m. muscular 



fascicle. 



1 1 . One of the i)oslerior nephridia seen under a low magnifying power in order to show the peritoneal covering 



and the general outline of the canals in the lower peritoneal lobe. a. f. anterior fold of canals. /)./. posterior 

 fold of canals, xpn. the partially free spur. s. septum. nsl. nephrostome. «/<. nephropore. »■. I. the 

 wule tube leading to the nei)liropore. hr. bridge connecting the spur with one of the folds. u. I. upper 

 lobe of peritoneal cells which docs not contain any canals, e. I. connecting lobe. I. I. lower lobe. The two 

 peritoneal lobes vary greatly in shape and hardly two are found exactly alike, though the |general form is the 

 same in all. 



