386 NOTES ON AUSTRALIAN EARTHWORMS, 



on either side of and arching above the alimentary canal ; ciliated 

 rosettes two pairs in x and xi, the whole vacant space in these two 

 segments crammed with masses of fully formed and developing 

 spermatozoa, apparently enclosed in very thin-walled sacs with the 

 ciliated rosettes in each segment, but in too friable a condition to 

 make out their relations thoroughly ; prostates two, lobed masses 

 each consisting of an anterior broader portion and a posterior 

 narrow and longer portion, much bent on itself so as lie in 

 two segments xviii and xix, or as on one side in xviii only ; a 

 short duct conies off at about the junction of the broad and narrow 

 portions of the gland ; the posterior portions of the vasa deferentia 

 were not visible : the two ovaries occupy the usual position in xiii ; 

 the two oviducts commence opposite to them in the same segment 

 and open to the exterior in the next segment ; spermathecse two 

 pairs in viii and ix, stalked pear-shaped pouches opening ante- 

 riorly, each with a short wide caecum placed anteriorly and which 

 may be more or less bifid or even trifid at the free extremity. 



The mesenteries after the first two or three complete ones as far 

 back as that between xiii and xiv are enormously thick, and con- 

 nected by interseptal bands ; the posterior one of xiv is thinner, 

 but much thicker than the succeeding ones. 



There are hearts from v to xii, the last three pairs the largest, 

 and these arise by two trunks, one from the dorsal vessel and one 

 from a small supra-intestinal trunk ; I could see no sub-nervian 

 trunk, but in addition to the supra-nervian one there are two 

 lateral vascular trunks in the anterior region of the body. 



The segmental organs are apparently the small tufts of tubules 

 attached to the coelomic wall immediately in front of and behind 

 the mesenteries, and most conspicuous in some of the anterior 

 segments. 



Hah. — Morpeth, and Hawkesbury River District, N.S.W. 



This species cannot be referred to the genus Trigaster recently 

 established by Mr. Benham for the reception of a West Indian 



