neto Earthrrorma in the British Museum. 289 



consist of an ovate sac, from the anterior larger extremity of 

 wliicii arises a thick duct, the length of which is only a little 

 less than that of the sac ; the diverticulum is equal in length to 

 the main pouch -with its duct, and consists of a narrow nearly 

 straight tuLe with a small terminal dilatation. 



I am not aware of more than ten species of Perichceta with 

 only one pair of spermatheca? opening between segments 

 7 and 8 ; of these species only P. novarce, Rosa ( = P. taitensiSj 

 Grube, partim), and P. sangirensis, MichaelseUj may suggest 

 an identity with our species. 



Unfortunately we know nothing concerning the anatomy of 

 P. novarce *, as I did not like to injure the only specimen 

 that had corae into my bands (it was one of the two 

 types of P. taitensis, under which name Grube has con- 

 founded together two distinct species)* Nevertheless I 

 believe that we can discard the idea of an identity between 

 P. novarce and P. zonopora, as P. novarce shows no dorsal 

 pores upon the clitellum, while P, zonopora [as well as 

 P. Gruhei, Eosa (P. taitensis, Gr., partim)] shows them very 

 clearly. 



As to P. sangirensis f, it is a larger species, provided with 

 a smaller number of setge and also with large sperm-sacs and 

 sperm-reservoirs. The ejaculatory duct, too, differs, being- 

 described by Michaelsen as short (and therefore probably 

 straight) ; moreover, no mention is made by Michaelsen of 

 the presence of dorsal pores upon the clitellum. 



Perichceta peguana, Rosa \. 



Hah. Chantaboon (Siam). 



This species was described by me eight years ago from 

 specimens collected by Signor L. Fea at Rangoon. 



In the specimens from Chantaboon the copulatory papillae 

 lying on the intersegmental grooves between segments 17-18 

 and 18-19 show a very convex surface, and are surrounded 

 by a slightly raised ridge, giving them an eye-like appearance. 



As regards the internal characters I have been able to 

 satisfy myself that the gizzard belongs to the 8th segment 

 (not to the 9th), and that the missing septa are those between 

 segments 8-9 and 9-10. 



Perichceta posthuma J Vaill. 



Ilah. Christmas Island. 



* Ann. k. k. naturh. Hofmuseum, Wien, Bd. vi. p. 39G. 



+ Jahrb. d. Hamburg, wiss. Anstalten, viii. p. 36. 



X Ann. Mii3. Civ. Genova, ser. 2, vol. x. (1690) p. 113. 



