210 GASTROPODA. [Pectinibranchia. 



18. Rissoa subfusca, Hutton, 1873. Plate 12, fig. 18. 



Rissoa subfusca, Hutton, C.M.M., 28. R. purpurea, Hutt., C.M.M., 29 : 

 Man. Conch. (1), ix, 344, pi. 71, f. 89. R. purpurea, var. subfusca, Hutt,. 

 t.c., 344. R. subfusca, Hutt. : Suter, P. Mai. S., iii, 4. 



Shell small, subulately elongated, imperforate, solid, polished. 

 Sculpture : The protoconch is microscopically finely spirally striate, 

 the interstices minutely punctate ; the following whorls show traces 

 of microscopic spiral striation, otherwise they are smooth ; the oblique 

 close and fine growth-lines are distinctly visible under the lens. Colour 

 of the upper whorls purple or purplish-red, the last whorl usually of a 

 lighter colour, mostly yellowish ; a light band below the suture. Spire 

 elevated conic, twice the height of the aperture, outlines straight. 

 Protoconch small, globose, of 1^ convex whorls. Whorls 6, regularly in- 

 creasing, flat ; base rounded. Suture not deep. Aperture rounded, sub- 

 vertical. Peristome continuous, much thickened inside, and slightly 

 expanded. Columella short, very callous and reflexed. Operculum 

 unknown. 



Diameter, 1-25 mm. ; height, 2-5 mm. 



Animal unknown. 



Type in the Dominion Museum, Wellington. 



Hob. Stewart Island (type) ; Port Pegasus, Stewart Island, in 

 18 fathoms (Captain Bollons) ; Foveaux Strait ; Cook Strait ; Omaha 

 (C. Cooper) ; near the Snares Islands, in 50 fathoms (Captain Bollons) ; 

 Dusky Sound, in 30 fathoms (R. Henry). Also Victoria. 



Subsp. micronema, Suter, 1898. 



Rixsoa subfusca, Hutt., subsp. micronema, Suter, P. Mai. S.. iii, 4. 



Shell more slender. Sculpture of the protoconch the same as in 

 the species ; the following whorls are finely spirally lirate ; the growth- 

 striee are oblique, rather distant and prominent, decidedly more so 

 than the spiral sculpture. Colour pink or yellowish -pink, the last 

 whorl getting yellowish-white on approaching the mouth. Spire sub- 

 cylindrical, twice the height of the aperture. Suture submargined. 

 All the other characters are those of the species. 



Diameter, 1-25 mm. ; height, 3 mm. 



Animal unknown. 



Type in my collection. 



Hab. Stewart Island, in 15 fathoms, type (A. Hamilton) ; Wha- 

 ngaroa Harbour (C. Traill) ; near the Snares, in 50 fathoms (Captain 

 Bollons) ; Banks Peninsula (Iredale). 



19. Rissoa zosterophila, Webster, 1905. Plate 12, figs. 19, a, b. 



Bwfta zosterophila, Webster, T.N.Z.I., xxxvii, 1!)04 (1905), 277, pi. 9, f. 5. 

 R. ininulata, Hutton : Suter. P. Mai. S., iii, 3 ; Index, 77, not of Hutton. 

 R. zosteropliila, Webst. : Suter, T.N.Z.I., xxxviii, 327. 



Shell minute, oval, subrimate, dull, smooth. There is no sculpture. 

 Colour dark red-brown with a broad milk-white band below the suture, 

 base of the same colour, thus leaving a brown peripheral band on the 



