218 RETUSA. 



as the shell, straight and narrow behind, wide and somewhat oblique 

 in, front; max. lou. of shell, 5"0 ; max. lat. 3'0 ; lat. of apex, 1*75 

 mill. {Dall). 



Off Bah ia Honda, Cuba, in 220 fms. ; Barbados, '[QO fms, 



Coleophysis perplicatas Dall, Blake Rep. Gastr., p. 45. 



It is difficult, or rather impossible, to determine the generic place 

 of these small Tectibranchs without a knowledge of the soft parts. 

 They are referable to Coleophysis, Cylichna, or Diaphana, or even 

 Sao, at the option of the describer guided only by the characters of 

 the shell. The presence of the plait would indicate the first men- 

 tioned section for the present species. It is perhaps nearest in 

 general form to the Cylichna ovata of Jeffreys, or Diaphana gemma 

 of Verrill, which has no plait and is much more attenuated behind. 

 {Dall). 



R. SPATHA Watson. PI. 25, figs. 53, 54, 55. 



Shell large, cylindrically oblong, gradually and slightly narrow- 

 ing forwards, more abruptly so up the short stumpy and very blunt 

 spire, thick, exquisitely reticulated, with a truncated and toothed 

 pillar and a straight, slightly contracted outer lip. Sculpture : Lon- 

 gitudinals — the whole surface is delicately and sharply scored in the 

 lines of growth with very fine rounded furrows parted by sharper 

 and much narrower ridges, which are about xaVo of an inch apart. 

 Spirals — a little stronger than the longitudinals which they cut 

 across, are spiral lines very distinct above, one or two on the 

 shoulder being even stronger and remote, more delicate and similar to 

 the longitudinals in front, and in the middle very faint indeed, only 

 sufficient to produce a satiny sheen ; round the top of the whorls 

 below the suture is a very broad shallow furrow or slight constric- 

 tion bordered by a very feeble keel below, which forms a vague 

 shoulder. Colour ivory-white. Mouth {' of the whole length of the 

 shell, in shape somewhat clavate, being shortly broad in front, elon- 

 gately conical throughout the most of its length, and rapidly con- 

 tracted at the top. Whorls 2*, rounded above with a very slight 

 concave constriction below the suture, subcylindrical in the middle 

 and rounded in front. Suture linear, impressed, and very slightly 

 horizontally margined below. Outer lip contracted amd appressed 

 above, so that the top of the mouth runs up to a long and very nar- 

 row point, bluntly angulated at the shoulder, below this it is straight 

 but draws in towards the axis, in front it is patulous and well 



