TRIFORIS. 181 



minutely margined above and below, with two spiral rows of tuber- 

 cles, connected in each row by a spiral thread, and a much smaller 

 row of granules next below r the suture. Length, 15 mill. 



West Indies, 390-640 fins. 



T. cylindrellus, Dall. (unfigured), is referred here by Jousseaume, 

 and T. abruptus, Dall. ,( unfigured), is said to be a variety. 



T. HEBES, Watson. PL 37, fig. 2. 



Solid, translucent white, whorls 12, with three 'spiral rows of 

 strong tubercles, separated by spiral squared channels, margin of 

 base defined by a thread. Length, 6 mill. 



Tristan da Cunha Islands, So. Atlantic 0. 



T. INFLATA, Watson. PI. 37, fig. 3. 



Solid, opaque, glossy, white ; whorls 13, the normal ones slightly 

 convex, with two spiral rows of tubercles, separated by a narrow 

 triangular furrow, below them is a wider furrow, extending to the 

 suture, above the suture is defined by a narrow marginal line, which 

 is undulated rather than tuberculated. Length, 5 mill. 



West Indies, 390-640 fins. 



T. ASPERA, Jeffreys. PI. 38, fig. 5. 



Rather solid, nearly opaque and glossy, pale yellowish, with a 

 faint tinge of brown, apical whorls dark brown; whorls 21-22, 

 with two spiral series of strong tubercles and a subsutural series of 

 minute granules, base with two spiral lines, and defined by a strong 

 peripheral ridge, suture slight. Length, 15 mill. 



Bay of Biscay ; Sciacca, Sicily ; Gulf of Mexico. 



More slender^ w r ith stronger tubercles and more abrupt base than 

 T. perversa. 



T. ASPERRIMUS, Hinds. PI. 38, fig. 6. 



Whorls 24-26, angulated in the middle, with two spiral series of 

 tubercles, granularly carinate near the suture. Length, 13'5 mill. 



New Guinea. 



Distinguished by its very narrow form. 



T. GEMMULATUS, Ads. and Reeve. PL 38, fig. 7. 



Pyramidal, with abruptly plain base, pellucid white ; w r horls 12- 

 15, with three distant series of granules, the central one narrow, 

 almost obsolete, causing the whorls to be concave in the middle, 

 suture defined by a marginal line. Length, 7 mill. 



China Sea. 



