KEPORT ON THE GASTEROPODA. 565 



rounded thread occupying the extreme upper edge of the subjacent whorl. This thread is 

 undulated rather than tubercled where it crosses the longitudinal rows ; on the spireward 

 side this thread is defined by a minute deep square-bottomed trench, while on the basal 

 side it lies close in upon the foot of the upper spiral row of tubercles. Round the edge of 

 the base is a slight sharp narrow keel, which the succeeding whorl as it grows buries in 

 the spiral thread mentioned above. At 0"004 from the edge, and there forming a ledge, 

 the whole centre of the base is slightly projected ; with this exception, the flat and scarcely 

 conical base has no ornamentation beyond the radiating lines of growth and the microscopic 

 spirals, which, though visible on the rest of the shell, are, as usual, more distinct on the 

 base. Colour dull translucent white. Spire high, narrow, and conical. Apex blunt and 

 inflated. The two embryonic whorls are larger, but otherwise very much like those of 

 Bitt'mm metula (Loven), being turban-shaped and projecting beyond the succeeding whorls ; 

 they are glossy and quite smooth, but for some very faint microscopic longitudinal and 

 spiral lines. Whorls 13 in all, of very gradual increase, flat on the sides ; the base, too, 

 is flat, and very little conical. Suture linear, almost hidden by the overlap of the subjacent 

 whorl. Mouth very small and square, with a minute, round, very short canal in front, 

 whose edges are reverted all round. Outer lip broken. Pillar very small, extremely 

 short, straight, but reverted at the point. Inner lip not fully formed. H. 0'2 in. B. 0'06. 

 Penultimate whorl, height 0'02. Mouth, height 0-028, breadth 0-025. 



This species, which in shape resembles Triforis suturalis, Adams and Reeve, may be easily 

 distinguished from that species by the absence of the deep suture, and by the inflated apex. From 

 Triforis hebes, Watson, its sculpture and its apex distinguish it at once. 



6. Triforis dolicha, 1 n. sp. (PI. XLIL fig. 1). 



Station 188. September 10, 1874. Lat. 9° 59' S., long. 139° 42' E. West of Cape 

 York, North-east Australia. 28 fathoms. Green mud. 



Shell. — Long and narrow, conical, pale, spotted with brown, with three rows of fine 

 tubercles on the later whorls and two on the earlier, a furrowed suture, a small regularly 

 tapering apex, and a square barely produced base. Sculpture : Longitudinals — there are 

 on each whorl about 16 riblets, which originate at the upper row of tubercles, and swell 

 down to the lower ; they are parted from each other by little shallow pits, and they but 

 feebly and doubtfully run down the spire, being not quite coincident in the adjoining 

 whorls, and being parted by the sutural furrow ; near the outer lip the riblets subside into 

 continuous bars, which are prolonged to the base. Spirals — on the last four whorls there 

 are three, on the earlier two, rows of tubercles set upon the longitudinals, and slightly 

 connected in each row by a fine thread ; round the angle of the base runs a sharp rounded 



1 doXi^oi, long. So called from its narrow form. 



