248 



SIPUNCULACE^E. 



dorsal and ventral surfaces, and are most numerous at the 

 posterior extremity, which tapers to a point. The pro- 

 boscis (which is retracted in the figure, drawn from a 

 specimen in spirits) is about one-third the length of the 

 body, and is provided towards its extremity with a circle 

 of tentacular filaments, flattened, lanceolate, and jagged, or 

 digitate at the edges. The vent opens near its back. On 

 opening the creature we find no dental processes, but a 

 digestive apparatus, consisting of a narrow oesophagus, 

 which opens into an intestine twisting spirally on itself to 

 the posterior extremity of the body, and then returning in 

 a similar manner along the same spiral to the vent, on each 

 side of which is a short brown muscular tube, probably 

 respiratory. The vascular system is complicated, and the 

 nervous consists of a strong nervous cord, which runs 

 along the abdominal surface of the animal terminating 

 posteriorly in numerous filaments, and anteriorly by two 

 delicate threads which surround the oesophagus where it 

 joins the base of the proboscis. 



The vignette is a view from Leith Roads. 



