Troc. Roy. Soc. Victoria, 22 (N.S.), Pt. 1., 1909.] 



Aii'i. VII. — Cunfr'ihutum^ to our liiouiedge of 

 A vstralian Earth u'orms. 



Thk Blood Vesskls — Part I. 



By GAVYXXETH BUCHANAN, B.Sc, 



Government Research Scholar in the ^Melbourne University. 



(Plates XlV.-XVir.). 

 Read Hth July;;. 



Mr. J. J. Fletcher and Professor Spencer, in their general 

 descriptions of Australian earthworms, have dealt briefly with 

 certain of the main features of the arrange)nent of the blood 

 vessels. In connection with an extended series of investigations 

 into the structure of Australian earthworms, which is now being 

 carried on in the Biolog'cal Laboratory of the Melbourne Uni- 

 versity, Professor Spencer has sua-gested that I should under- 

 take the portion concerned with the blood vessels. The pre- 

 sent communication forms the first instalment of this work, and 

 I am indebted to Professor Spencer for the use of specimens 

 from his collection, as well as for much valuable advice during 

 the progress of the work, further instalments of which I hope 

 to publish shortly. 



The species examined belong for the most part to the Genera 

 Megascolides, Megascolex, Perichaeta, Diporochaeta and Crypto- 

 drilus, and I have to thank Miss Bage, M Sc, for the use and 

 explanation of her lists of the names and synonyms of the speci- 

 mens in the collection. I have only given descriptions of dis- 

 sections in most cases, as, for the present paper, I have not 

 examined microscopicallj' more than three worms — viz., Peri- 

 chaeta feJderi, FletclierndrUus iinicu'^ and ('n/ptodrilu-'^ {irpp^- 

 landicus. Of the first of these, serial sections were taken at 

 the anterior and tail end ; of the latter two, only at the 

 anterior end of the recfion of the hearts. These two were 



