BRITISH MARINE TURBELLARIA. 491 



between tide-marks (Mcintosh) ; among littoral algse, Ply- 

 mouth (P. W. G.) . 



Distribution. — Bergen (Jensen), coast of Denmark 

 (Fabricius, Oersted), Greifswald (Schultze), Madeira (Langer- 

 hans), Black Sea (XJljanin; Czerniavsky). 



56. AUTOMOLOS HORRIDUS, n. sp. PI. XLI, fig. 21. 



Length 15 mm. Body somewhat flattened. A slight 

 constriction occurs at the level of the otolith, separating oflf an 

 anterior conical portion. Behind this " neck " the body 

 gradually increases in width, to the posterior third of its length 

 which ends in a sharply pointed " tail." Pigment is absent, 

 the gut alone giving a grey tinge to the otherwise white body. 

 Flagella are present at each extremity, and also occur at 

 intervals for a short distance behind the anterior end. Packets 

 of rhabdites occur in large numbers on the surface of the 

 body (fig. 21). Adhesive cells are present, although feebly 

 developed, on the tail. The musculature is strong, enabling 

 the animal to execute very active movements, and to flex the 

 sides of the body ventrally towards the middle line. The 

 mouth lies at the commencement of the posterior third. The 

 pharynx, inserted into the gut at the centre of the body, is 

 cylindrical and very muscular. The intestine lies chiefly in 

 front of the pharynx. Its cavity is produced into about twelve 

 cseca on each side, [)laced fairly symmetrically. The specimen 

 under examination was starved, and in this condition the 

 limits of the gut branches can be clearly defined. Brain 

 placed behind the otolith, oval, the long axis coinciding with 

 that of the body. An eye is absent. Testes in this specimen 

 not well developed. They occur behind and at the sides of 

 the brain. Vasa deferentia open behind the pharynx into a 

 vesicula seminalis, surrounded by accessory glands. The 

 penis is pyriforra and muscular. The single pair of ger- 

 maria lie opposite the base of the pharynx. Elongate yolk- 

 glands are placed at the sides of the gut. An accident pre- 

 vented the determination of the oviducts. 



