288 Dr. D. Rosa on some 



duct at the end of the ejaculatory duct, and in the shape ot 

 the spermathecffi. 



Perichceta zonop07-ay sp. n. (PL IX. fig. 16.) 



ffab. ? (with P. recta) . 



Of this species I have been able to examine several speci- 

 mens measuring 80-90x4 milhm., with 105-110 segments; 

 the colour (in spirit) is light fleshy grey. 



The prostomium is small and dovetailed in the first segment 

 for one third of the length of the latter. 



The seta3 number 30 on segment v., 44 on xii., and 60 on 

 XXV. ; they are closer together ventrally. 



The clitellum extends over three entire segments, without 

 visible setee. 



The large male openings are on yellow, radially corrugated 

 areas which extend to the intersegmental furrows; the pores 

 are in a line with seta 7; between the two pores there are 

 six setffi. 



The oviducal pore on segment 14 lies in a darker oval 

 areola surrounded by a light ring. 



The spermathecal pores (one pair only) lie between seg- 

 ments vii. and viii. at the level of the 9th seta. 



The dorsal pores begin between segments 11-12; in all 

 the specimens these pores are conspicuous also upon the 

 girdle, a character which is rarely met with among Perichetm, 

 There are no copulatory papillee. 



Septa 5-6, 6-7, and (a little more) septa 10-11, 11-12 are 

 thickened, but not very much ; septa 8-9 and 9-10 are 

 absent or rudimentary. 



The gizzard is long, tun-like, and comes immediately after 

 septum 7-8 ; the two intestinal ca3ca are simple. 



The last heart is in segment xiii. 



The two pairs of sperm-sacs occupy segments 11 and 12; 

 they are but little developed. 



The prostates extend through three segments ; they are 

 relatively narrow, with two deep notches on the outer side ; 

 the ejaculatory duct is very long, U-shaped, and terminates 

 in a moderate bulb. The inner wall of the body presents 

 at the inner (mediad) side of the bulb a glandular swelling, 

 which is enlarged in front of the bulb and behind it, so that 

 its outline recalls that of a figure of 8. 



The only pair of spermathecal, which opens between seg- 

 ments 7-8, does not lie in segment 8 but in segment 7, that 

 is the spermatheca3 lie in front of the groove which bears 

 their external opemngs and not, as usual, behind it. They 



