TRICIIOTIIOI'TS. 43 



affecting the contour and general appearance. I incliule here : 

 2\ Atlantica^'^Qok; T. acuminata^, ieil'voys; T. co^tellata, Couth. 

 (fig. 48); T. inermis, Hinds (fig. 52); Fuhuh Lat^keiji^ Macgill.; 

 Fusus nmhilicatiis, Brown ; T. cunica, Moll. (fig. 45); T. quadin- 

 carinata^ A. Ad. (fig. 44), from Japan ; T. inaignis^ Midd., var. 

 of Anrivillius (fig. 50). 



T. CLATIIRATA, A. Ad. PI. 7, fig. 51. 



Umbilicus narrow, whorls anguhir, carinated above, cancel- 

 lated with sliglitly beaded spiral ribs and interstitial regular, 

 small, longitudinal riblets ; epidermis thin, j-ellowisli brown. 



New Zealand. 



T. inornata, Hutton, is a S3'nonym. I have not seen this 

 species, which so greatly resembles T. borealis, but is from an 

 entirely different localit}'. The figure shows no trace of hairs 

 on the epidermis. 



T. CANCELLATA, Hinds. PI. T, figs. 49, 50. 



Umbilicus small, whorls about 7, well rounded, with elevated 

 spire, with a number of spiral ribs, obsoletely cancellated here 

 and there b}' distant longitudinal and less prominent ribs ; epi- 

 dermis light brownish or grayish ; aperture often pink. 



Length, 1-1-4 inches. 



Alaska to VanconveT''s Idand. 



Appears to be peculiar to the west coast of North America, 

 where it replaces T. horealia. Jeffreys considers it identical 

 with that species, and as Arctic moUusca are exceedingly varia- 

 ble, this may be so ; yet I find no conclusive evidence of it. T. 

 Jlavida, Hinds (fig. 50), belongs here, 



T. coRONATA, Gould. PI. 7, figs. 53, 54. 



Umbilicus rather wide and deep, acutel}' margined ; whorls 

 about 6, tabulate and carinate at the angle; epidermis ash- 

 colored, fibrousl}' produced at the angle. Length, 25 mill. 



Sis. of Semiavine^ Arctic Ocean; Behring^s Sea. 



The fii'st figure given above is supposed by Krause, who 

 publishes it, to represent the species, but it does not appear to 

 me to agree with the description, Gould never figured it. I 

 have added a figure given by Anrivillius, which is probably a 

 better representation of it, and approaches T. unicarinata. 



