Mr. A. Adams on the Animal and Affinities of Fenella. 39 



granular protoplasm of even the largest tentacula) ; e represents 

 a portion of the parenchyma which appears to protrude after 

 rupture of a contracting vesicle (thus apparently showing that 

 the fluid contents of this organ are expelled externally);/,/, ve- 

 siculae or contracting vesicles ; ^, nucleus? h, bodies like the 

 *' reproductive cells ;" i, portions of food in process of digestion, 

 among which is a rotiferous animalcule ; A:, a tentaculum, trun- 

 cated in the drawing only. N.B. The body has not been filled 

 up with the vacuolar parenchyma, nor have the actiniform tenta- 

 cula been scattered over it, as in nature, to save trouble in the 

 drawing, &c. 



Fig. 22. The same, magnified small specimen of (?), with the actiniform 

 tentacula bearing little pellets of the investing membrane (?). 



Fig. 23. The same ; another specimen (?), where the investing membrane 

 is carried out by the tentacula into an arachnoid form ; the body 

 presenting the nucleus and a portion of crude food. 



Fig, 24. The same ; another specimen (?), where the investing membrane 

 has not only been carried out into an arachnoid form, but appa- 

 rently has also assumed a hastate form at the ends of the tenta- 

 cula respectively. 

 Figs. 22-24 are drawn upon no scale, but in body may be set down 

 as about -j^th or -B-o-D-tli of an inch in diameter respectively. 



Fig. 25. Acanthocystis turfacea, n. sp. etgen., magnified; on the scale of 

 -rVth to T^Wth of an inch : a, body ; b, minute, curved, fusiform 

 spicules covering the capsule ; c, c, c, forked spines ; d, d, d, ten- 

 tacula, granuliferous ; e, nucleus ; /, vesicula discharging itself ; 

 g, chlorophyll-cells ; h, starch- granules ; i, a spine, more magni- 

 fied ; k, proximal or discoid end ; I, distal or forked end ; m, more 

 magnified representation of a fusiform spicule. 



IV. — On the Animal and Affinities of Fenella; with a List of 

 the Species found in the Seas of Japan. By Arthur Adams, 

 F.L.S. &c. 

 In the 'Annals^ for 1860 I described some exquisitely sculp- 

 tured little shells under the common appellation of Dunkeria, a 

 form of Pyramidellidse separated by P. P. Carpenter from Tur- 

 honilla on account of their convex whorls. At Takano-Sima, on 

 the East coast of Niphon, I afterwards discovered the animal of 

 my genus Fenella (by mistake printed Finella in the ' Annals ' 

 for 1860), and found it to possess all the characters of a Rissoid. 

 A comparison of my Dunkeria and Fenella pupoides has con- 

 vinced me that they all belong to the same Rissoid group. 



The species I examined was the original type, Fenella pupoides, 

 A. Ad. It occurred in tolerable abundance on a sandy-mud 

 bottom, in 2 fathoms water, at Takano-Sima. The head is broad, 

 dilated, and flattened ; the muzzle large, long, annular, and of a 

 pale brown colour, edged with white. The tentacles are small, 

 filiform, wide apart, and of an opake-white colour. The eyes 

 are small, black, and sessile, in the centre of white spaces on the 

 sides of the head, behind the bases of the tentacles. The foot is 



