SYSTEMATIC ^9 



produced forwards in a considerable arcuate sweep. Parietal and columellar callus smooth, porcellanous, 

 and abruptly marked off from the surface sculpture. 



Height 38-75 mm.; diameter 11-5 mm. (St. 1952, holotype). 



Height 43-5 mm.; diameter 13-0 mm. (St. 1957). 



Type locality. St. 1952. Between Penguin I. and Lion's Rump, KingGeorge I., South Shetland, Is., 

 2 Jan. 1937, 367-382 m. 



St. 170. Off Cape Bowles, Clarence I., 6i° 25' 30" S, 53 46' W, 23 Feb. 1927, 342 m. 



St. 175. Bransfield Strait, South Shetlands Is., 63° 17' 20" S, 59 48' 15" W, 2 Mar. 1927, 200 m. 



St. 182. Schollaert Channel, Palmer Archipelago, 64 21' S, 62 58' W, 14 Mar. 1927, 278-500 m. 



St. 1957. Off south side of Clarence I., 7 miles east of Cape Bowles, South Shetlands Is., 3 Feb. 1937, 785-810 m. 



In its slender form the species resembles Leucosyrinx tenoceras Dall from off Gaudeloupe in 

 583 fathoms (18896, p. 76, pi. 36, fig. 5). 



Leucosyrinx paragenota n.sp., PL IX, fig. 56 



Shell of similar shape and proportions to paratenoceras, but smaller, with finer and more numerous 

 spiral cord-sculpture, the whole of the shoulder spirally lirate, a shorter anterior canal and a much more 

 prominent fasciole. Whorls seven, including a rather large papillate protoconch of 1^ smooth whorls 

 plus a brephic half-whorl of closely spaced sinuous axials. Post-nuclear sculpture consisting of closely 

 spaced spirals crossed by numerous oblique axials. Five weak spiral threads on the narrow concave 

 shoulder, nine to fourteen flat-topped, linear-spaced cords from the shoulder to the lower suture, and 

 about thirty-six on the body whorl from the shoulder to the fasciole, which bears approximately 

 a further fourteen spirals, but they are closely spaced, weak and ill-defined threads. Axials narrow, 

 protractively oblique and extending from the shoulder to the lower suture, eighteen to twenty per 

 whorl, but subobsolete on the body-whorl. Aperture narrow, with a very short, spout-like anterior 

 canal. Anal sinus deeply concave, occupying the whole of the shoulder. Outer lip produced forwards 

 in a considerable arcuate sweep. Fasciole prominently bulging, commencing above the middle of the 

 aperture. Parietal and columellar callus smooth and porcellanous, abruptly marked off from the 

 external sculpture and not interrupted by the fasciole. Colour white, covered with a thin, buff-coloured 

 epidermis. 



Height 21-25 mm.; diameter 7-5 mm. (holotype, St. 652). 



Type locality. St. 652. Burdwood Bank, south of Falkland Is., 54 04' S, 6i° 40' W, 14 Mar. 1931, 

 171-169 m. Protoconch. Fig. N, 113, p. 196. 



Leucosyrinx falklandica n.sp., PL IX, fig. 55 



Shell very similar to paragenota, but with a larger, more bulbous protoconch, a smooth shoulder and 

 an inconspicuous fasciole. Whorls six, including a large, bluntly rounded smooth protoconch of two 

 whorls, followed by a half-whorl of closely spaced, strong, brephic axials. Post-nuclear spiral sculpture 

 consisting of flat-topped, linear-spaced, spiral cords, extending from the shoulder to the lower suture, 

 nine to eleven on the spire-whorls and about forty on the body-whorl including the ill-defined 

 fasciole. Axials prominent, protractively oblique, commencing at the shoulder, but becoming obsolete 

 towards the lower suture and on the last half-whorl. Colour white, covered by a pale buff epidermis. 

 Apertural features and sinus as in the above two species. 



Height 15-75 mm - '■> diameter 5-8 mm. 



Type locality. St. WS 871. North of Falkland Is., 53 16' S, 64 12' W, 1 Apr. 1932, 336-342 m. 



(one example only). Protoconch. Fig. N, 112, p. 196. 



162 



