274 DR Johnston's descriptive catalogue of the 



Hab. Slow streams and ponds. In the Tweed and Whiteadder near Berwick, 

 plentiful. 



This shell is plentiful in the marl duj^f out of peat bogs. When living it is of a 

 pale-gi-eenish horn colour, transparent and marked with a few dark lines, 

 whii-h sliew the course of the intestine. The animal is white and vivacious, 

 gliding along the bottom with its tentacula widely spread, the posterior 

 one projecting from under the ujiper angle of the aperture, or swimming 

 with ease in a reversed position on the surface. Month proboscidiform 

 darker: tentacula three, setaceous, lateral: eyes sessile, superior, at the 

 base of the anterior tentacula : near the posterior tentacnlum there ia 

 occasionally extruded an elegant plumose appendage supposed to be sub- 

 servient to respiration : foot transparent white, oblong, wider and rounded 

 behind, in front produced on each side into an acutely triangular process. 

 Operculum horny, with circular strias. 



2. F. cristata, shell depressed, corneous, with four whorls flat above, 

 the base widely and deeply iinibilicate exposing the rounded 

 whorls ; aperture circular. Diam. 2 Knes. Flem. Brit. Anim. 286. 

 Turbo cristatus, Billiv. Rec. Sh. 883. 



Sah. Ponds. In the Whiteadder near Berwick. 



The animal is strictly aqtiatic, and never leaves the water even when confined 

 to a small vessel. It can creep along ths surface with the shell reversed. 

 Behind the two anterior tentaua'a is a third, as in the preceding species, 

 but the plumose appendage I have not seen, though the animal has been 

 kept for several days together to allow repeated examinations. Eyes at 

 the base of the anterior tentacula, rather prominent, with a light areola. 

 Foot bilobed in front, the lobes becoming triangular when fully extended, 

 posteriorly rounded. 



The Paludina achatixa I have occasionally found on the shores of our bay, 

 having been brought in ballast from the Thames. 



17. Tornatella. Lamarck. 



Shell oval or oblong, with a short rather obtuse spire ; aperture 

 longitudinal, elongated, contracted above and widened below ; 

 outer lip simple, acute ; pillar with one or more plaits. 



1 . T. fasciato, shell ovate, pale-purplish red, the body marked with 

 two distant white bands and spirallj' striated ; spire smaU, coni- 

 cal, of six whorls ; aperture white, the pillar with an oblique fold. 

 Length -/oths ; breadth yV^bs. Lam. Anim. s. Vert. vi. ii. 220. 

 T. tornatilis, Flem. Br. Anim. 336. Voluta tornatilis, Billw. 

 Rec. Sh. 503. 



Rah. Berwick Bay, very rare. 



The striee are much stronger and wider apart at the base of the shell. 



18. Stylifer. Broderip. 



Shell thin and transparent, spiral with a produced apex ; aperture 

 somewhat ovate, narrowed above, with an acute sinuated lip : no 

 operculum . — Zo ophagous. 



