NEW OR IMPERFECTLY KNOWN SPECIES OF EARTHWORMS. 23 



is uot so, and that we have uot made any statement to that effect. We have headed 

 our "paper, " New or Imperfectly Known Species, etc.," and it was not our intention to 

 rcdescribe the species which we thought had been sufficiently well described. As a 

 matter of fact Perichœta Ijimœ Rosa, P. jaj)onica Horst, and P. Sieboldi Horst are the 

 only species already described which we have not yet come across. 



We have not minutely described our species because its characters were exactly 

 similar to those of P. Sieboldi except in the points specified by us, viz. the position of 

 the spermathecœ and the number of setœ. As, however, Dr. Horst's reexamination 

 of his type specimen has confirmed these differences, we find it necessary to regard the 

 species in question as new, and we propose for it the name of 



29. Perichœta communissima, n. sp. 



Length 250 mm. or sometimes more, breadth 9 mm. ; number of segmets 140 in 

 the largest individuals; those measuring about 190 mm. and with about 100 segments 

 being, however, the most frequent. Clitellum XIV — XVI, without sette. Number 

 of setœ in the spermathecal region about 60. Spermathecal pores in V/VI, VI/VII, 

 VII/VIII. Male pores in XVIII, on top of papilke, separated by 14 — 19 setœ. No 

 genital papillae. First dorsal pore in XII/XIII. 



Gizzard in Vili, IX ; intestine beginning in XV, with 6 — 7 or exceptionally up 

 to 9 pairs of coxa* in XXVI, the size of which gradually decreases from the dorsum 

 towards the ventrum. Thickened septa V/VI — VII/VIII and X/XI— XIII/XIV ; 

 septa VIII/IX and 1X/X wanting in most specimeus, although we have observed a 

 few specimens in which septum VIII/IX was present but exceedingly thin. Sper- 

 mathectc three pairs, in VI, VII, VIII ; main pouch spherical and voluminous ; 

 diverticulum winding in its central part, longer than the main portion. Sperm 

 reservoirs large, in XI, XII, dorsal surface lobate. Ovisac in XIII, dorsal to the 

 ovary. Prostate gland very well developed, in XVII — XIX, trilobed, the middle 

 lobe being smallest, and all the three lobes with numerous lobules. Last heart 

 in XIII. 



Lo. — Tokyo, Sendai, Tsugaru (south side of the Strait of Sangar), Shizuoka, 

 Ibaraki, Bitchü ; that is to say all over the Main Island. 



After this description it is hardly necessary to remark that the present species 



can not be identified with P. Ijimœ Rosa. 



* The most dorsal cœcum is prominently larger than li e others, and is slightly separated from 

 them; but this is the case in aJl the srecies with numerous <aca that we have observed, viz. in 

 P. Hilgcndorfi, P. Masatokœ, P. divergent, I', schizopcra, !'■ irregularis, 1\ glandularis, and J', levis. 



