410 OLIGOCHAETA 



(19) Perichaeta sinensis, BEDDARD. 



P. sinensis, BEDDARD, P. Z. S., 1892, p. 158. 



P. monilicystis, MICHAELSEN, Arch. f. Nat., 1892, p. 251. 



Definition. Length, 126 mm. ; breadth, 3.5 mm. ; number of segments, 104. Colour pale 

 brown posteriori//, dar&er in front. Clitellum XIV-XVI without setae. Male pores 

 separated by six setae; behind and to the inside of each pore a papilla lying on 

 boundary line of XVIII, XIX ; a grape-like mass of white glands corresponds to each 

 papilla. The seta formula is : /, 28 ; F, 26 ; XII, 42 ; XXV, 48 ; setae of segments 

 VI-IX longer and stouter than those upon anterior and posterior segments ; this is 

 especially the case with those more laterally placed. Spermathecae four pairs in VI-IX; 

 diverticulum as long as pouch, but there is some variation; the diverticulum has 

 frequently a beaded appearance due to the existence of constrictions at regular intervals. 

 Spermiducal gland has no terminal sac connected with the muscular duct. Hab. 

 Foochow, China (also found by MiCHAELSEN in a forcing house in Botanical Gardens of 

 Berlin). 



I have figured the living worm, the genital papillae and clitellum, the spermatheca 

 with its contents, and the vascular network upon it (PL ix, figs. 3 and 5 ; PL x , 

 2, 3. 4, 7, 8). 



(20) Perichaeta bermudensis, BEDDABD. 



P. bermudensis, BEDDABD, P. Z. S., 1892, p. 160. 



Definition. Length, 120 mm. ; breadth, 4 mm. ; number of segments 93. Colour reddish 

 brown dorsally, passing into a yellowish ventrally. Clitellum XIV-XVI ; setae (about 20) 

 on XVI. Male pores close to the ventral median line ; behind each pore is a group of 

 about Jive papillae. Setae small on the first setigerous segment; they gradually increase 

 in size on the next three and then get small again; they are quite small on segment 

 IX. Dorsal pores commence X/XI. In segments V and VI are blood-glands. Sperma- 

 thecae two pairs in VI, VII, VIII ; each has a single diverticulum about half as 

 long as the pouch. In segments XIII and XIV are the egg-sacs. The sperm-sacs are 

 in XI, XII. Spermiducal gland has no terminal dilatation. Hab. Bermudas. 



I formerly (45) confounded this species with P. aspergillum ; it is. however, 

 evidently distinct. The principal difference is the fact that in P. aspergillum all the 

 segments of the clitellum are furnished with setae, and that there are papillae in the 

 neighbourhood of the spermathecae as well as the Spermiducal glands ; and it is 

 furthermore a considerably smaller species. 



