47 



thin and fragile, glossy and smooth, or at least without longitudinal sculpture; apex with a 

 projecting pipe or a simjde orifice; no slit, rarely a notch. 



Inhabitants of moderately or very deep water in the Mediterranean, Atlantic, Gulf of 

 Mexico and Pacific. 



The small accessory tube or pipe at the apex is frequently developed in most, perhaps 

 all, of the species grouped here; although most young and many adult shells lack it. (P. & Sh.). 



The subgenus EpisipJion consisted hitherto of 7 species of which D. siibrecUun Jeffreys 

 only habitated the Indo pacific province. Most of the species are rather hard to distinguish, 

 the difterences being principally based on highly variable characters, as size, rate of increase, 

 curvature and colour. Young specimens are often very different from adults of the same species, 

 as is proved by D. carneiLiii of which one specimen measuring 18,5 mill. has a greatest diam. 

 of 1,4 mill. while a much younger individual measuring 15,5 mill., has a greatest diam. of 

 0,8 mill. It is therefore often practically impossible to draw conclusions about the species, if 

 the material is not large enough. 



Key to Species. 



a. Shell whitish or delicately salmon-tinted subrectum. 



b. Shell deeply flesh-coloured carnetim. 



55. Dc7ita.liui)i siibrcctuiu Linné. PI. VI, figs 46 — 50. 



1882. Dentalhtui subrectum Jeffreys, Proc. Zool. Soc. p. 661 (see under D. filuiiï). 



1897. Dcntaliuui subrectum Jeffreys. PiLSBRY & Sharp, Man. of Conch., vol. XVII, p. 119, 



pi. 18, fig. 5- 

 Dcntaliuin subrectum Sowerby in part. (those reported from the Philippines) Conch. 



Icon., pi. 5, fig. 31 (not fig. 32!) 1860. 



Stat. 4. Anchorage oft" Djankar (Java) 7°42'.6S., ii4°i2'.6E. 9 Metres. Coarse sand. i Spec. 



Diagnosis. Shell acicular or needle-shaped, thin, extremely slender, tapering almost 

 to a point, nearly straight, translucent whitish, with the faintest reddish tint from the middle 

 to the apex. Surface very glossy, smooth, with faint growth striae only. Aperture not oblique, 

 circular. Anal orifice minute, circular, with thin, entire edge. Length 16, diam. of aperture i mill. 



Distribution. Philippines (Cuming); Batavia (Prof. Sluiter). 



R e m a r k s. A young specimen was obtained by the Siboga. It is much acuminated and 

 with a length of 16 mill. has a greatest diam. of i mill. There are moreover several specimens 

 brouo-ht by Prof. Sluiter from Batavia. I have identified them with subrectum., and hold them 

 for older than Jeffreys' types. Here follows a more exact description of .Sluiter's specimens : 

 Shell narrow, slender, cylindrical, moderately curved, acuminated in young, truncated in adults ; 

 quite smooth, with hardly perceptible growth striae; colour whitish, very delicately salmon-tinted, 

 especially near the shell's middle, with some opaque white bands. Apex attenuated and simple 

 or truncated with very thick walls and a small supplemental tube. Anterior aperture rounded, 

 sometimes a little oblique. 



