Oligochaeta.'] SUBANTARCTic ISLANDS OF NEW ZEALAND. 291 



EXPLANATION OF PLATES X AND XI. 



Plate X. 

 Phreodrilus camfbellianus. 

 Fig. 1. Longitudinal section through the sperm- and spermathecal pores, combined from two conse- 

 cutive sections. (Camera outline, x 100 ; details somewhat diagrammatically sketched 

 in.) a, spermiducal pore in xii : b. penis in its sac ; c, prostate, in transverse section ; 

 d, neck of prostate entering penis ; e, spermathecal pore in xiii ; /, spermathecal antrum, 

 surrounded by muscles ; g, narrow duct of spermatheca. 



Rhizodrilus aucklandicus. 



Fig. 2. Transverse section through the paired male pores. (Camera, x 60 ; details of body-wall diagram- 

 matically sketched.) a, male pore; 6, penis-sac, with sperm-duct above; c, nerve-cord; 

 d, intestine, to the left of which are the dorsal and ventral blood-vessels ; e, sperm-sac. 



Fig. 3. Spermatheca, from a transparent specimen, a, ampulla ; h, globular, glandular sac ; c, epi- 

 dermal pit ; d, spermatozoa projecting from the pore. 



Fig. 4. Base of the penis, in transverse section (c/. d in fig. 7). ( x 370.) 



Fig. 5. Sperm-duct, in transverse section, with prostate glands surrounding it. The groups of glands 

 are confined to the dorsal and lateral surfaces, each group being enveloped in a sheath 

 of coelomic epithelium. (Camera, x 370.) 



Fig. 6. The lower part of the penis, in transverse section (at about the level of c in fig. 7) ; the wall is 

 a good deal folded, d, lumen. (Camera, x 370.) 



Fig. 7. Longitudinal section through the male apparatus. (Camera, x 250.) The region from the 

 funnel to the upward curve of the duct lies in one section, the posterior part- was contained 

 in several consecutive sections, a, male pore ; h, muscular penis-sac ; c, penis, folded 

 protrusible portion ; d, glandular bulb ; e, sperm-duct ; /, prostate glands enveloping 

 the duct for the greater part of its length ; g, retractor muscles of penis ; y' , retractors 

 of the sac ; », s', septa 10/11 and 11/12. 



Lumhricillus irUermedius. 

 Fig. 8. Spermatheca, from a bisected specimen. (Camera x 60.) a, pore, surrounded by a rosette of 

 glands ; h, aperture into oesophagus. The thicker portion of the wall is the muscular duct. 

 Fig. 9. Subneural gland. (Camera, x 18.5.) 



Fig. 10. Sperm-funnel, from a longitudinal section, which cuts it lengthwise. (Camera, x 100.) 

 Fig. 11. Nephridium, combined from two consecutive sections. (Camera, x 370.) 



Pelodrilus tuberculatus. 



Fig. 12. Transverse section of the body, at the level of the copulatory gland, showing the circum- 

 ferential extent of the clitellum and the position of the gland through which the sperm- 

 ducts open (c/. fig. 14). n, copulatory gland ; 6, clitellum ; c, large ovum. (Camera 

 outline, x 35.) The chaetae are inserted on one side only, and the body-wall is represented 

 diagrammatically. 



Pig. 13. Portion of the body-wall, enlarged. (Camera, x 370.) The cuticle (a) is remarkably thick ; 

 6, goblet cells : c, circular muscles ; d, longitudinal muscles. 



Fig. 14. Longitudinal section through the genital segments, which are numbered above in roman 

 numerals. (Camera, x 100.) o', a', the male pores ; b, female pore ; c, c', the sperm- 

 ducts ; d, oviduct ; e, the copulatory (? prostate) gland. 



Plate XI. 



Pelodrilus nttckinndicus. 

 Fig. 15. Longitudinal section through the genital segments, which are marked in roman numerals 

 below. (Camera, x 60.) The two limbs of the sperm-duct lie almost wholly in two con- 

 secutive sections, a', a', the male pores ; b\ b', the female pores ; c, testis ; d, sperm- 

 funnel ; e, sperm-duct ; /, copulatory (? prostate) gland ; g, oviduct ; h, ovary (the other 

 ovary is omitted for sake of clearness) ; /, base of chaetae (the entire chaeta is represented 

 in segment x). 



