i 5 4 DISCOVERY REPORTS 



From shackletoni the South Georgian subspecies differs in having fewer and more prominent axial 

 lamellae. In Cape Royds and South Georgian shells of adult size the lamellae number from twelve to 

 fourteen in the former and from seven to ten in the latter. Hedley's series consisted of ten examples 

 and mine of five adults and six juveniles, so the differences noted appear constant enough to warrant 

 separating the South Georgian shells as a new regional subspecies. 



Dentition. Fig. L, 82, p. 194 (St. 144). The central tooth is very broad and shallow, slightly arched 

 and bears three long slender main cusps and two intermediates which lie close to the outer cusps. 



Trophon brevispira von Martens 



Trophon brevispira Martens, 1885, p. 91. 



Trophon brevispira Martens & Pfeffer, 1886, p. 68, pi. 1, figs. 1a, b. 

 Trophon brevispira Strebel, 1908, p. 42, pi. 4, fig. ^8a-c. 

 Trophon brevispira L. David, 1934, 2-3, p. 128. 



Type locality. South Georgia. 



St. WS 25. Undine Harbour (north), South Georgia, 17 Dec. 1926, 18-27 m - 

 St. 45. 2-7 miles S 85 E of Jason Lt., South Georgia, 6 Apr. 1926, 238-270 m. 



Only worn empty shells from both stations and evidently washed down from shallow water. 



Trophon distantelamellatus Strebel 



Trophon distantelamellatus Strebel, 1908, p. 43. 



Type locality. South Georgia, 54 23' S, 36 26' W, 64-74 m. 



This species bears close resemblance to young, non-eroded examples of albolabratus, but differs 

 constantly in its narrower proportions and regularly crenulated axials. 



St. MS 10. East Cumberland Bay, \ mile south-east of Hope Point to \ mile south of Government Flagstaff, 



South Georgia, 14 Feb. 1925, 26-18 m. 

 St. MS 67. East Cumberland Bay, 3 cables north-east of Hobart Rock to A cable west of Hope Point, South 



Georgia, 28 Feb. 1925, 38 m. 

 St. MS 71. East Cumberland Bay, 9! cables E x S to 1-2 m. E x S of Sappho Point, South Georgia, 9 Mar. 1926, 



110-60 m. 



Dentition. Fig. M, 87, p. 195. 



Height 40-0 mm. ; diameter 18-0 mm. (holotype, albolabratus). 

 Height 24-5 mm.; diameter 16-0 mm. (holotype, cinguliferus). 

 Height 15-1 mm.; diameter 7-9 mm. (holotype, distantelamellatus). 

 Height 15-0 mm.; diameter 7-8 mm. (St. MS 67, distantelamellatus). 

 Height 19-0 mm.; diameter 9-2 mm. (St. MS 10, distantelamellatus). 



Trophon ohlini Strebel 



Trophon ohlini Strebel, 1905a, p. 203, pi. 3, fig. ga-e. 

 Type locality. Puerto Harris, 15 fathoms, Patagonia. 



St. WS 80. Between Falkland Is. and Patagonia, 50 58' S, 63 39' W to 50 55' 30" S, 63 36' W, 3 Feb. 1927, 



152-156 m. 

 St. WS 216. North of Falkland Is. and east of Cape Blanco, Patagonia, 47 37' S, 6o° 50' W, 1 June 1928. 



219-133 m. 

 St. WS 225. Between Falkland Is. and Patagonia, 50 20' S, 62 30' W, 9 June 1928, 162-161 m. 

 St. WS 243. Between Falkland Is. and Point Santa Cruz, Patagonia, 5 1° 06' S, 64 30' W, 17 July 1928, 144-141 m. 



Dentition. Fig. L, 84, p. 194. The basal plate of the central tooth is broad and shallow, slightly 

 arched, and bears three tall narrowly triangular main cusps of equal size and two well-developed inter- 

 mediates, two-thirds the height of the main cusps. 



