23 8 DISCOVERY REPORTS 



like enlargement. The eyes are embedded within the longitudinal muscle layer. The 

 second pair occurs immediately before the brain. The cerebral organs are very small. 

 They lie in front of the brain and their canals open behind the first pair of eyes into a 

 transverse lateral groove that occurs on each side of the head. 



Nearly ripe eggs were present in some specimens. The eggs are shed just above the 



lateral nerves. 



In two particulars — the yellow rather than rose colour of the body and the presence 

 of a head gland — this description differs from that of Burger. 



Another specimen (N 109) was identified from sections. It was 10 mm. long, 0-3 mm. 

 broad, bleached and coiled. This was taken at St. WS 4 in 40 m. 



Genus Amphiporus, Ehrenberg 



Amphiporus pulcher, Johnston, 1837 (Plate XV, fig. 13). 



Two specimens (N 36) were taken from attached and washed-up kelp roots in Sep- 

 tember 1926 on the southern point of Saldanha Bay. The lengths and breadths were 

 3-5 cm., 1-5 mm., breadth of head i-omm.; 4-2 cm., 17 mm. (swollen with eggs). 



Form and colour in life. The body is round anteriorly, somewhat flatter and wider 

 posteriorly. The head is a little flattened, almost semicircular in outline from above, but 

 has a slight snout. The mouth, proboscis pore and cephalic slits are not visible, but a 

 chevron groove can sometimes be seen at the back of the head. The colour is pinkish 

 yellow or buff, lighter anteriorly and deepest on the back. The ganglia show red through 

 the skin. About ten eyes are visible on each side in no definite order, but there is usually 

 a row of four in a line nearly parallel to the edge of the head from the tip to the widest 



part. 



Form and colour of preserved specimens. In spirit the worms are white and contracted. 

 Cephalic grooves appear as vertical furrows at the sides behind the head, curving for- 

 wards ventrally. The proboscis pore is ventral to the tip of the snout in a furrow that 

 passes vertically round the head. 



Internal structure. Well developed head glands are present but they do not reach the 

 brain. There is a strand close above the rhynchodaeum which stretches back beneath 

 the vascular loop almost to the ganglia, and more diffuse glands among the muscles of 

 the head which become restricted near the ganglia to the sides of the body cavity inside 

 the longitudinal muscles. The duct of the head gland opens just ventral to the tip of the 

 snout. The eyes are embedded deeply in the tissues of the head. 



The epithelium is thinner than the longitudinal muscles and about three times as 

 thick as the basement membrane and circular muscles together. The basement membrane 

 is twice as thick as the circular layer and appears to contain fibres. The epithelium con- 

 tains a large number of eosinophile cells. 



The oesophagus opens into the rhynchodaeum in front of the brain. The stomach 

 walls are not much folded and most of the cell contents stain deeply with haematoxylin. 

 The anterior caecum has forwardly directed branches, two of which extend beyond the 



