210 (jii'ijn ii^'lli BacliaiKiii : 



Woodwardia gippslandicus. 

 Perichaeta obscura. 



„ manni. 



,, macquariensis. 



,, valida. 

 While those described in the present one are 

 Cryptodilus grandis. 



,, manifestus. 



,, saccarius. 



Megascolex australis. 

 Notoscolex camdenensis, 



„ qneenshmdica. 



1. — Megascolex australis, Fletcher. 



Perichaeta australis, Fletcher. Proc. Linn. 8oc. 

 N.S.W., vol. i., 188G. 



Plate XL., Fig \. 



Dorsal vessel single, swollen in segments 15-10, and passing 

 forward to the first segment, when it sends an exceedingly fine 

 branch round the alimentary canal, which unites with the 

 ventral on each side. In 15 and IG it gives off two well marked 

 vessels to the alimentary canal in each segment, while in 14 

 there is only one, and in 13 none at all. In 12, 11 and 10, a pair 

 of hearts arise in the hinder part of each segment, whose con- 

 nections with the dorsal vessel are so small as to be only dis- 

 ■cernible in serial sections, the hearts arising from a very definite 

 supra-i?itestinal, which takes its origin as a separate vessel 

 over the alimentary canal in 13, and which runs forward to end 

 blindly over the same organ in 9. From 9-6 distinct commis- 

 surals pass from the dorsal at the hinder end of each segment 

 to the ventral vessel, sending a branch to the posterior septum 

 and ventral l)ody wall. From 5 forwards these vessels are very 

 small, and hard to trace among the exceedingly strong 

 jnuscles, but there is a))parently one leaving the dorsal and 

 entering the ventral in each segment. In 5, that from the 

 doi-sal breaks up into tine capillaries, al)0ut half way down the 

 .segment, which ai)]tcar to conned with another set associated 



