192 GASTROPODA. [Pcctinil>i-<nirli:<i . 



blade ; the third is a, simple elongated blade ; all three have long, 

 narrow bases. Hutton, T. N.Z.I., xiv. 164. pi. 7, f. B ; Kesteven, 

 Rec, A.M., iv, 319, fig. 29. 



Type in the Dominion Museum, Wellington. 



Hob. Throughout New Zealand and at the Chatham Islands ; at 

 and above high-water mark, on rocks, often hiding in clusters of 

 Modiohts ater. 



Var. carinata, Kesteven, 1902. Plate 35, fig. 14. 



Risellopsis varia, Hutt., var. carinata, Res., Rec. A.M.. iv, 1902, 321, f. 33-35 

 in text. 



Shell depressed trochiform, tabulate. Sculpture : Two prominent 

 spiral carinse divide the shell into a superior, peripheral, and basal 

 area ; there are on the superior area 2 small riblets one (the smaller) 

 at the suture, the other a little less than a third of the breadth of the 

 area from the suture ; on the base there are 3 spiral riblets of about 

 equal size, and a smaller one round the umbilical tract. Seen from 

 below, the mouth is somewhat rhomboidal, with one rounded side, 

 the basal margin. Operculum and dentition, as in the species. 



Diameter Maj., 5 mm. ; min., 4-3 mm. : height, 3 mm. 



Type in the Australian Museum, Sydney. 



Hob. The same as the species. 



Remark. Differs from typical examples in the development of the 

 2 peripheral keels, to which is due the difference in contour. 



Fam. FOSSARIDJE, Fischer. 



Animal having the head proboscidiform, with a median longi- 

 tudinal sulcus ; tentacles thread-like, sharp, grooved ; eyes at their 

 external base ; 2 frontal lobes between the tentacles ; foot obtuse 

 at both ends. 



Central tooth of the radula with a triangular, finely dentate cusp ; 

 lateral tooth transverse, with a strong cusp and a series of fine denti- 

 culations its entire length ; marginals elongated, simple- 

 Shell turbinated, rather solid, white, grooved or ribbed spirally ; 

 aperture entire ; lip simple, undulated ; columella nearly straight ; 

 operculum corneous, subconcentric or subspiral. 



Genus 1. COUTHOUYIA, A. Adams. 1860. 

 Couthoinjia, A. Ad., A.M.N.H. (3), v. 18(50, 410. Type : C. tlccit^itft. A. Ad. 



Shell ovate, profoundly and widely rim ate ; spire acuminated ; 

 whorls convex, decussated, with impressed suture ; aperture semi- 

 ovate ; inner lip straight, dilated in front ; outer lip arcuate, simple. 



The type is from Japan. Indian Ocean and Australasia. 



Fossil in the Pliocene of New Zealand. 



