MOLLTJSCA OF THE ' CHALLENGER EXPEDITION. 221 



intermediate threads ; the first two whorls are smooth. Colour a 

 brownish yellow, with ruddy spots of undefined outline. These 

 spots on the keels are large, on the intermediate threads they are 

 small ; they follow in their direction the curves of growth ; the 

 upper part of the spire and the middle of the base have a suf- 

 fused stain of this colour. Spire is high, narrow, and perfectly 

 conical. Apex very fine, ending in a minute, transparent, glassy 

 knob, which is not in the least depressed or spread out. Whorls 

 15-16, of very gradual increase, almost flat on the sides, with a 

 strong constriction below and a more gradual contraction above; 

 the upper whorls are angulated. There is a slight contraction, 

 and within that an angulation round the edge of the base, which 

 is flatfish and slightly conical. The first two are hyaline. Suture 

 sharp and strongly defined. Mouth rather large, almost round. 

 Outer lip scarcely advancing, sweeping freely out with a rounded 

 curve from the body to the pillar, and rather patulous throughout, 

 especially at the point of the pillar, where there is a slight canal. 

 Between the two keels there is a deep V-shaped sinus, the form 

 of which is preserved in the curves of growth. Inner lip is 

 spread as a thin brown glaze, which just encompasses the base of 

 the pillar. The pillar is narrow, rounded, with the lip-edge just 

 turned back on it ; it is curved and rather bent backward ; the 

 basal lip sweeps out beyond the point of it. H. 1-15. B. 034, 

 least 0'31. Penultimate whorl, height 0'18. Mouth, height 0*21, 

 breadth 0-17. 



There are unnamed specimens of this species on a tablet in 

 the British Museum numbered " 924 1. Bass Strait, 40 fins." It is 

 very like Turritella pagoda, Eve. ; but that is a narrower shell, of 

 slower increase, and with fewer spirals. T. sinuata, Eve., is also 

 slimmer and smoother, of slower increase, flatter whorls, and 

 finer apex. T. Gunnii is very like, but is smoother, and has a 

 still deeper and more impressed suture. In general aspect of 

 form, colour, and sculpture it resembles T. conspersa, Ad. & Bve. ; 

 but the resemblance utterly disappears on closer observation/ 

 That is broader and squarer in the base, the colour is more blotchy 

 and less suffused, the upper whorls of the spire are finer, the 

 suture is much more impressed, and the whorls are much more 

 angulated ; it has no deep labial sinus, nor is any trace of that 

 left on the lines of growth. The T. incisa, Tenison Woods, 

 45 fms., from Port Jackson, has the deep narrow sinus of this 

 species, but seems to be a much smaller shell relatively to the 



17* 



