264 



SUBANTARCTIC ISLANDS OP NEW ZEALAND. 



[Oligochaeta. 



Pklodriluh tubbbculatus. 



View of genital region. 



a', a*, the two pairs of male pores, 

 situated on a glandular pad or cojni- 

 latory organ ; 6, the oviducal jmre; 

 c, sijerinathecal pore. The circular, 

 vertically striated areas are the tu- 

 bercula pubertatis. 



Genital Pores. — There are two pairs of male pores, the anterior pair on the hinder 

 margin of 11, the posterior pair a little behind the middle of 12. These pores are 

 situated on the glandular copulatory ridge, and therefore are in line with the ventral 

 chaetae. The single pair of female pores are at 12/ 13, 

 in the same line. They are slitlike, and visible under a 

 pocket-lens in some individuals. 



The single pair of spermathecal pores are rather 

 high up the side of the body, at about the lateral line, 

 at 7/8. 



Internal Anatomy. 



The epidermis consists almost entirely of very large 

 gland-cells, opening through the very thick cuticle by 

 distinct pores. The cuticle is nearly as thick as the 

 epidermic layer. Squeezed between the gland-cells are 

 a few columnar cells (Plate X, fig. 13). 



The septa behind 6, 7, 8, 9, and 10 are thickened. 



The dorsal vessel contains a large " cardiac body " 

 m the 14th and some segments anteriorly. Free com- 

 missural vessels, more or less undulating, are visible in 

 each segment, though they were not followed out in 

 detail. 



The nephridia are of large size in proportion to the 

 size of the worm. They are present in 6, 7, 8, 9, 13, 

 14, &c. I am not satisfied as to their occurrence in the 10th ; they are certainly 

 absent in 11 and 12. 



The pharynx occupies 2, 3, and 4, and has the typical dorsal pad. There is no 

 gizzard. The oesophagus is narrow, has folded walls from the 7th to 14th ; the 

 intestine commences in the 15th. 



Septal glands lie in 5, 6, and 7. 



There are two pairs of testes and sperm-funnels in the normal position in seg- 

 ments 10 and 11. They are, in opposition to Beddard's statement for P. violaceus, 

 not contained in sperm- bladders ; segments 11 and 12 are, however, filled with 

 developing sperms. 



There is a paired sperm-sac in 9, and the segments 10-16 are filled with 

 developing spermatozoa. 



The sperm-fimnel is large and flat, with the lower margin upturned ; the 

 greater part of it is free from the septum, to which it is attached by only quite 

 a small area ; its margin is somewhat folded. 



Each sperm-duct is a delicate tube, coiling immediately after perforating the 

 septum, and opens independently by a very fine pore through the glandular ridge 

 on segments 11 and 12 respectively (Plate X, fig. 14). The histology of this ridge 

 or copulatory gland is quite distinct from that of the cUtellum, where the epithelium 

 consists of small ovoid cells filled with large refringent spherules, which are not 

 stained by borax -carmine, though they take carm-alum powerfully. The cells of 

 the copulatory gland, however, are long, club-shaped, and filled with very fine 

 granules that are stained in borax-carmine, and recall those of a prostate. 



