1881.] THE SURVEY OF H. M.S. * ALKRT. 37 



Apparently distinct, although a near relation to //. saxatUis 

 of Couthouy, from Tierra del Fuego. 



SucciNEA PATAGONiCA, sp. n. (Plate IV. figs. 17, 17«.) 



Shell ovate, somewhat ventricose, greenish yellow, with the apex 

 light scarlet. Whorls 3, very convex ; the last somewhat elongated, 

 striated by the lines of growth, and separated by a deepish suture. 

 Mouth ovate, equalling rather more than two thirds of the entire 

 length. Columellar margin obliquely arcuate, with a thinly reflexed 

 enamel extending to the termination of the outer margin. Length 

 12| millims., diani. from lip to opposite side of the whorl 8, aper- 

 tui-e 9 long and 6 broad. Another specimen is 9 millims. long, 6^ 

 broad, and its aperture has a length of 6| and a width of 5. 



Hub. Cockle Cove, found on dead leaves ; also shores of Trinidad 

 Channel and Puerto Bueno. 



This species is mainly distinguished from /S. jnagellanicu of Gould 

 by its scarlet apical whorl, the second or penultimate being rather 

 less shouldered ; and the suture, too, is scarcely as deep. 



c. Fluviatile. 



Chilina am(ENA, sp. n. (Plate IV. figs. 18, 18a.) 



Shell very fragile, ovate, acute above, greenish yellow, with trans- 

 verse bands of dark reddish brown, more or less arrow-head-shaped 

 spots or marks, which sometimes flow into one another from band to 

 band, thus forming longitudinal zigzag streaks. Of these series of 

 spots the body-whorl has five— one immediately beneath the suture, 

 and the others atsubequal distances ; that which is a little above the 

 middle of the whorl and runs into the suture of the penultimate whorl 

 is, in the eight specimens before me, narrower than the bands imme- 

 diately above and beneath it. The whorls are well rounded, about six 

 in number, and striated with the lines of growth. Aperture inversely 

 subauriform, coated with a thin bluish-white enamel, but exhibiting 

 the exterior banding, and, as a rule, occupying about f of the entire 

 length of the shell. Columella a little oblique and arcuate, with a 

 single fold at the upper part, white, somewhat reflexed beneath 

 the fold, and with a thin callosity above it. Length 26 millims., 

 diam. 11, aperture 14| long and 6 broad. 



Hah. From a lake near Tom Bay. 



The spire in this species is quite as long as in C. parchappi, 

 d'Orbigny, from which species it differs in the brightness and distinct- 

 ness of coloration, the greater convexity and shouldering of the 

 whorls, and the different character of the columella. C. pulchra, 

 d'Orb., is more like in colour; but its form is much more stumpy, 

 and the columella and the fold upon it are considerably thicker and 

 heavier than in the present species. 



III. CONCHIFERA. 



Venus, sp., jun. 



Hab. Station 2. * . 



Of this species there are two specimens, which apparently are \m- 



