212 Givyn neth Buclian an : 



2. — Notoscolex camdenensis, Fletcher.^ Proc. Linn. 8oc. 

 N.S.W., vol. i., 1887. 

 Cryptodrilus camdenensis, Fletcher. 



Plate XL., Fig. 2. 



Dorsal vessel single, swollen in segments 17-14, less so in 

 13-10. It passes forward to 1, where it apparently breaks up; 

 but from 4-1 the muscles are ver}^ thick, and in these segments 

 the connections between the dorsal and ventral, if present, are 

 indistinct. In 17-14 the dorsal gives clear vessels to the calci- 

 ferous glands, and posterior to these in each segment one or 

 two branches to the alimentary canal, whose connections with 

 the ventral are small, and barely to be made out even in 

 sections. From 9-6 a pair of commissural vessels arises from 

 the dorsal at the hinder end of each segment, showing some 

 distance along their course a construction probably due to the 

 presence of a valve. From this point (which is higher than in 

 the other vessels) in 6, arises a lateral passing backwards, and 

 closely applied to the alimentary canal. BeloAv the valve the 

 commissural give l)ranches to the posterior septa of the seg- 

 ments, there being many of these vessels in 6. The lateral is 

 fairly distinct in 7, 8 and 9, closely applied to the alimentary 

 canal, receiving vessels, from it, and sending branches to the 

 posterior septa ; but in the region of the hearts it becomes in- 

 distinct, and only apparent as the suh-intestinal on each side 

 in sections, where it is seen to end in the sinus around the 

 alimentary canal in 13, sending small branches to the posterior 

 septa in iO-13. The hearts are four pairs, in segments 10-13, 

 arising mainly fiom the f-^tpra-intestinal, but each receiving 

 a small branch from the dorsal. They are somewhat monilform 

 in appearance, and fine at their junction with the ventral, and 

 in section are found to contain valves, which have also been 

 noticed in the hearts of other worms. (See Beddard, p. 73.) 



The supra-intestinal arises as a definite vessel from the sinus 

 around the alimentary canal in 13, and passes forwards to end 

 above that organ in or about segment 9. It is the main origin 



1 Michaelsen retains Flctclioi's ffeniis Notoscolex " Die Fauna, Siidwest Aiistraliens," 

 1007, Olitrochaotii, j). HW. 



