THE NEPHRIDIA OP THE POLYOHiETA. 747 



genital funnel. There is as yet no direct communication between the cavities 

 of tlie two organs. Cam. oil ini. y\-, oc. c. 



Fig. 29. — Similar section throui^h the junction of the nephridiura and the 

 genital funnel in a ripe male Eteone lac tea (from whicli specimen fig. 18 

 has already been given). The communication is established, and ripe 

 spermatozoa can be seen further down the nephridial duct. Cam. oil im. ^j, 

 Oc. 4 0. 



Fig. 30. — Similar section througli the junction of the genital funnel and 

 nephridium in Pionosyllis sp. (same series as Fig. 20). The actual opening 

 of the one into the other is not cut through. Cam. oil im. j^, oc. 3. 



PLATE n. 



Fig, 31. — Two halves of transverse sections through a segment of Noto- 

 mastus latericeus, showing the genital funnels. An asterisk marks the 

 level of the genital pore. On the left hand side the backward prolongation 

 of the lip of the funnel is seen ; but it does not reach the nephridium. 



Fig. 32. — Similar sections farther back, showing the nephridium. The 

 level of the nephridiopore is marked by an asterisk. 



Fig. 33. — Portion of a longitudinal vertical section of a Nephthys cseca, 

 into the coelom of which some Indian ink has been injected. The nephridium 

 and genital funnel (ciliated organ) are cut through, and the latter is seen to 

 dip into a sac in which are accumulated numbers of amcebocytes loaded with 

 the insoluble black granules. Cam. D, oc. 2. 



Fig. 34. — Optical section of the nephridium from an anterior segment of a 

 young Trypanosyllis. From the living. Oil im. ^Vj oc. 3. 



Fig. 35. — Portion of a longitudinal section of a young Syllis vivipara 

 (median segment) passing through the nephridial funnel. Cam. Oil im. J^» 

 oc. 4 c. 



Fig. 36. — Optical section of the nephridium of a posterior segment of a 

 mature Syllis vivipara. From the living. Oil im. J^^, oc. 6 c. 



Fig, 37. — Portion of a longitudinal section of a segment of the non-repro- 

 ductive region of Haplosyllis spongicola passing through the nephridial 

 funnel. Cam. Oil im. y^, oc. 4 c. 



Fig. 38. — Transverse section (somewhat oblique) through a median segment 

 of a ripe male, Pionosyllis sp. As in fig. 20, the spermatozoa are omitted. Tlie 

 genital funnel shows on the left, and the nephridial duct on the right. Cam. 

 A, oc. 3. 



Fig. 39.— Portion of a transverse section of a non-productive segment of 

 Haplosyllis spongicola, showing the lower lip of the nephrostome, and 

 the upper lip (=: rudimentary genital funnel ?). Cam. Oil im. ^, oc. 4c. 



