[Pkoc. Roy. Soc. Victokia, 23 (N.S.), Pt. I., 1910]. 



Art. XVI. — Note on a Supposed Nematode Parasitic 

 in the Circular Muscle of am Earthivorin. 

 (DiporocJaieta grandis). 



By GWYNNETH BUCHANAN, M.Sc, 



Government Research Scholar in the Biological Laboratory, 

 University of Melbourne. 



(With Plates XX., XXI.) 



[Read 14th July, 1910.] 



While examining some speciniens of the earthworm Diporo- 

 chaeta (jraiidis'^ from Endeavour River, Queensland, I was 

 struck by the appearance of some curious yellow patches scat- 

 tered at irregular intervals over the external surface of certain 

 individuals. These patches measure about 3 mm. by 1 mm., 

 and are slightly raised. 



On opening several under the dissecting microscope, they 

 were found to contain a mass of structureless yellow material, 

 embedded in which was a single thread-like form, in many cases 

 much coiled. On clearing the contents of the patches in car- 

 bolised absolute (for the use of which and for valuable advice 

 I am indebted to Dr. G. Sweet), I found on examination two 

 distinct sets of thread-like forms closely resembling nematodes 

 in general appearance. 



The first (Fig. 1) had the ordinary truncated end of a nema- 

 tode, with a faint indication of a pharynx leading to an alimen- 

 tary canal, apparently ending abruptly in front of the sharply 

 recurved posterior end. 



The second (Fig. 2) was definitely pointed at each end, with 

 no apparent pharynx. None of the specimens were straight, 

 so that it was hard to obtain accurate measurements. The 



1 Spencer, " Further Descriptions of Australian Earthworms, Pt. I." Proc. Roy. Soc. 

 Victoria, vol. xiii. (1900), p. 63. 



