550 NOTES ON AUSTRALIAN EARTHWORMS, 



duct which is doubtless joined by the distal portion of the vas 

 deferens on each side, but owing probably to the condition of the 

 worms I have never been able to trace the exact connection 

 between them ; the common ducts open on the exterior of somite 

 xvin as previously mentioned. I have seen no trace of any 

 penial setae. 



The female portion of the generative organs comprises a pair of 

 ovaries, a pair of oviducts, and two pairs of spermathecae. The 

 ovaries are to be found without any difficulty on each side of the 

 nerve-cord, attached low down to the posterior surface of the 

 mesentery between somites xn and xm, and lying therefore in 

 somite xm. The oviducts commence by ciliated funnels on the 

 anterior face of the mesentery between xm and xiv, situated 

 opposite the ovaries, and, passing through the mesentery, are 

 continued as two short tubes which open to the exterior on the 

 ventral surface of segment xiv. Of the spermathecae there is a 

 pair in each of somites viii and ix. Each spermatheca is a long, 

 narrow sac, the distal portion cylindrical when distended, insensibly 

 diminishing towards the proximal portion which appears like a 

 long duct, often bent like a hoop, on which, at some distance from 

 the aperture, is a rudimentary caecum, small, broad, with its 

 summit marked with four little elevations so as to appear serrate 

 in outline ; the caecum projects backwards. The spermathecae 

 often, if not usually, aie folded inwards across the floor of the 

 somite, one overlying the other, beneath the sub-intestinal vessel. 

 They open anteriorly to the exterior by apertures of which one 

 pair is between somites vn and viii, and the other between viii 

 and ix. 



The vascular system presents two principal trunks, one supra- 

 intestinal and the other sub -intestinal. Transverse branches pass 

 from these trunks to the adjacent organs. They are connected by 

 eight pairs of "hearts" in somites VI to xm. There appears to 

 be no subneural vessel. 



Segmental organs of the type met with in Lumbricus are absent. 

 Attached to the coelomic wall are small tufts of glandular tubes, 

 most conspicuous in some of the anterior segments. 



