226 RET. E. BOOG WATSON ON THE 



to the summit of the spirals, while it stretches across the inter- 

 vening furrows. Operculum small, darkish brown, of very many 

 flanged whorls. H. 08. B. 0*25, least 0"21. Penultimate whorl, 

 height 0-12. Mouth, height 0*18, breadth 015. 



This species is very like our British Turritella terebra, L., but 

 is stumpier in form, smaller, with a much more impressed suture, 

 and fewer spiral threads. Than T. Hookeri, Kve., Antarctic Expe- 

 dition, this is also much stumpier, the apex is rounder and blunter, 

 and the suture is deeper. Than T. pagoda, live., from which 

 it also differs in form and suture, it is distinguished by a finer 

 apex, and in that the second spiral thread is much weaker than 

 in the ' Challenger ' species. Than T. hnysnaensis, Krauss, it 

 differs in being stumpier, with a finer drawn and yet at last ab- 

 rupter apex. It extremely resembles T. duplicata, L., but in 

 form is stumpier, and the spiral threads are fewer. T. triplicata, 

 Broc, has also more strong and very many more fine spirals. 



7. Turritella deliciosa, n. sp. 



St. 185 5. August 31, 1874. Lat. 11° 38' 15" S., long. 

 143° 59' 38" E. Eaine Island, Cape York, IN" . Australia. 155 fms. 

 Sand and shells. 



Shell. — Conical, with bicarinated contracted whorls and im- 

 pressed suture, rounded base, blunt, rounded, and slightly tumid 

 apex, porcellanous glossy white. Sculpture. Longitudinals — 

 there are very many, irregular, close- set, fine, strongly curved 

 lines of growth, which preserve the curve of the labial sinus. 

 Spirals — each whorl is carinated by two strong, broad, rounded 

 threads, of which the lower lies about one fourth of the height of 

 the whorl above the inferior suture, while the upper is slightly 

 nearer the superior suture. Close above each is a minute thread 

 which is like the shadow of the others. Between the two keels 

 the surface of the whorl is impressed by a broad, shallow, rounded 

 furrow, in the bottom of which is a spiral thread intermediate in 

 strength between the keels and their shadows. On the base there 

 are about nine small spiral threads, the innermost of which are 

 feebler than the rest ; they are parted by slight shallow furrows 

 which are narrower than the threads. The generic microscopic 

 fretting can only be made out in peculiarly good light ; but 

 though very faint, it is certainly present in the furrows. Colour 

 porcellanous, almost hyaline. Spire conical, drawn out, the pro- 

 file lines just a little interrupted by the carinations of the whorls. 



