608 



F. W. riAMBLK. 



Length IS— 3-75 cm. Breadth about half the length. 

 Body elliptical during motion, almost circular at rest, broadly 

 rounded behind. In front are two elongate tentacles. The some- 

 what convex dorsal surface is, with the exception of the margins, 

 opaque, of a bright orange-red colour dotted with white, due to 

 parenchymatous pigment, and to a greater extent to the contents 

 of the alimentary canal. In front an elongated, oval, raised, white 

 ridge represents the underlying pharynx. The ventral surface 

 is of a pale reddish colour, and upon it the gut, male and 

 female apertures, and sucker are visible. The mouth is one- 

 third of the distance from the anterior end to the sucker, i. e. 

 close behind the brain. The pharynx is well developed, 

 cylindrical, extending almost as far back as the centre, in front 

 of which it opens into the extensive main- gut. From this a 

 median and 5 — 6 lateral pairs of branches arise, which after 

 branching slightly end in marginal forked caeca. The minutely 

 moniliform appearance of these is due to the presence of 

 SDhincter-muscles at the points of constriction. Each tentacle 

 receives a Dranch of the intestine. Extending from the brain 

 towards the hinder margin of the pharynx are two groups of 

 eyes, which stand out very clearly against the white underlying 

 pharyngeal region. Posteriorly they are divergent, and con- 

 sist of small, loosely aggregated eye-specks, which become 

 larger and crowded in front, the two groups converging towards 

 the brain. Eyes are also present in the tentacles and around 

 their bases. The sucker is well developed, and serves to 

 attach the animal very iirmly to the substratum. The male 

 genital aperture lies under the hinder end of the pharynx. 

 The vasa efferentia unite in a large expanded duct on each 

 side, from which the two vasa deferentia arise. The ductus 

 ejaculatorius receives the contents of the granule-gland 

 and the large vesicula seminalis. Just in front of the sucker 

 lies the female pore, surrounded by the extensive radiating 

 shell-gland. The uterus lies at the sides of the main-gut. 

 A single pair of uterine glands are present. 



Habitat. — " On the coast of Berwickshire^ in deep water on 



