226 APPENDIX. No. V. 



wrinkly striated. The operculum is roundish, greenish yellow 

 on the inner side, and dirty yellow exteriorly ; and the nucleus 

 is rather less central than in B. Belcheri. 



Trichotropis tenuis, sp. nov. 



Shell very thin, light, semi-transparent, glossy white, 

 globosely turbinate, widely and openly umbilicated, clothed 

 with a dirty-yellowish epidermis, produced on the keels of 

 the whorls into close-set, very short, bristle-like filaments, 

 and rather coarsely obliquely striated, or rather lamellated, 

 marking periods of growth ; whorls 

 /A six, the two apical ones smooth and 



,_jlllil N rounded, the three following beauti- 



fully sculptured with raised oblique 

 lines of growth and minute spiral 

 striae, keeled and angulated a trifle 

 above the middle, convexly sloping- 

 above the keel and nearly straight 

 beneath it ; last whorl large, encir- 



TRICHOTROPIS TENUIS. 1 



cled with three iamt keels, two near 

 the middle and the third at the base, bordering the umbili- 

 cus ; aperture subcircular, occupying about T 6 T of the entire 

 length of the shell, whitish within, streaked with irregular, 

 curved, yellowish-olive stripes ; the peristome is continuous, 

 thin, with the epidermis produced beyond its extreme edges ; 

 columella white, arcuate, with a slight shallow channel at its 

 base. 



Greatest length 33 millims., diam. of last whorl above 

 the aperture 18, greatest diam. 30 ; aperture 18^ long, nearly 

 17 wide. 



Hah. Off Cape Louis Napoleon, Grinnell Land, 79° 38' 

 N. lat., in 25 fms. (Feilden). 



Only a single specimen of this grand new Trichotropis 

 was obtained. It is very different from any hitherto de- 

 scribed, being remarkable for its circular aperture, conical 

 spire, and extreme fragility. The entire surface under the 



