A ustraliii II Kiiilh a'oi'ins. 2 1 9 



canal wal]. The excessive development of blood vessels is a 

 marked feature of this segment, and is probably associated with 

 the well-marked " salivary gland." The commissural in 4 also 

 sends a branch back to break up on the alimentary canal. 



The hiterol is very large at its origin, though its connection 

 with the commissural is somewhat faint. It runs backwards, 

 sendin<r branches to the posterior septum of the segment in 6, 7, 

 8 and 9, and in 9 receives vessels from the calciferous gland. In 

 the anterior part of 10 it joins its fellow of the opposite side by 

 n single vessel, and from this point two continuations of the 

 laterals run back closely applied to the ventral wall of the ali- 

 mentary canal, and forming the suh-intestinal-<. In 10, 11. 12 

 and 13 vessels from the calciferous glands open to these. 



The veuti-dl vessel is single along its length, and becomes incon- 

 spicuous at its anterior end. In the region of the calciferous 

 glands, which are really highly vascular enlargements of the 

 alimentary canal, the branches from the supra-intestinal are 

 closely applied to the wall of the gland, and send vessels to its 

 villus-like projections on the internal surface of the gland. The 

 blood is then collected up wdth definite vessels (Br. Cal.). passing 

 to tlie sub-intestinal on each side. (See Fig. 8.) 



EXPLANATION OF PLATES XL.-XLTL 



Figs. l-t3. — Diagrams of side views of the cephab'c l)loo(l vessels 



of tlie earthworms named. 

 Fig. 7. — Dorsal view of the vessels at the origin of one of 



the hearts in C. nianifestua. 

 Fig. i"^. — ^Low power view of the blood supply to and from 



a calciferous sland of C. sdccarins. 



HEFERENCE LETTEllS. 



Al. C. - - Alimentary canal. 



B. - - - Branch from ventral vessel to septum and body 

 wall. 



