68 G THE VOYAGE OF H.M.S. CHALLENGER. 



Testa ininuta, subcylindrica, parum elongata, arcuata, flava vel albida, subopaca, niti- 

 dissima, Isevis sed subannulata, aperturam versus dilatata, annulo lato, rotundato, pro- 

 niinente terminata. Apertura paululo obliqua, haud contracta. Septo subplanato, paruru 

 expresso, vix conspicuo. 



Length, 0-074 in. to 0-079 in. Breadth, # 01G in. 



This species is nearly cylindrical, a good deal curved, rather long, amber-coloured or whitish or 

 yellowish, very glossy, nearly opaque. In some lights it looks as if girt by a series of very small 

 rings ; but there is no real swelling nor grooving, and the appearance of rings is probably only some 

 effect of reflection in connection with the texture of the shell. There is a broad and high ring 

 round the mouth. The septum is nearly flat, and projects so slightly as to be barely visible from 

 the side. 



This species may possibly be only a variety of Ccecuvi subflavum, de Folin ; but the difference 

 in the septum seems to individualise it. 



8. Ccecum microcyclus, de Folin (C/ECID^e, PI. III. figs. 17-19). 



Caecum microcyclus, de Folin, Caecidae of the Challenger Expedition, Proc. Zool. Soc. Lond., 1870, 

 p. 811. 



Station 1SG. September 8, 1874. Lat. 10° 30' S., long. 142° 18' E. Wednesday 

 Island, Cape York. 8 fathoms. Coral mud. Surface temperature 77°'2 F. Two 

 specimens. 



Testa subconica, elongata, arcuata, flavescens, nitidissima, subopaca, annulis multis 

 parum expressis cincta, aperturam versus paulo dilatata. Apertura haud obliqua, nee 

 contracta, haud marginata. Septo subungulato, submucronato, aliquando bimucronato. 



Length, 0-079 in. Breadth, 0-012 in. 



This beautiful species is long in proportion to its breadth ; it is conical, rather bent, yellowish, 

 very glossy and nearly opaque. The sculpture consists of numerous small rings, very close-set and 

 slightly prominent. It is sometimes as smooth as Ccecum succincum, de Folin, from which it differs in 

 its greater length, its more conical form, and the shape of its septum. The mouth is normal in its 

 relation to the axis ; it has no marginal ring ; and the shell expands towards it regularly without 

 any contraction. The septum is somewhat pointedly subungulated, presenting occasionally two or 

 three very similar protuberances. 



9. Ccecum elegantissimum, Carpenter. 



Caecum elegantissimum, Carpenter, Caecidae Monog., Proc. Zool.' Soc. Lond., 1858, p. 429, sp. 24. 



February 10, 1873. OffTenerife. 78 fathoms. Six specimens. 



These specimens present slight differences, but belong unquestionably to this somewhat variable 

 species. 



