252 Quatte)-ly /ounial of Conchology. 



Gonaxis, Taylor. 

 Shell pupiform, unsymmetricnl, axis of the apical whorls 

 diverted to the right, lower aspect of penultimate whorl of a 

 somewhat triangular shape, forming a prominent hump on the 

 left side. 



The most important character of this genus is the deflection of 

 the upper or apical whorls, Avhereas in Streptaxis it is the last 

 whorl only that is diverted from the perjoendicular. 



This peculiarity appears to me to be of sufficient importance to 

 warrant the erection of this genus. 



There has been some little uncertainty as to the systematic posi- 

 tion of Streptaxis, Messrs. Adams placing it in the subfamily 

 HelicincB, while Prof, von Martens in his edition of " Albers' 

 Heliceen," places it next Pupa and quite remote from Heiix. 



Gonaxis Gibbons!, n. s. (Plate II, fig. i). 



Animal small ; body of a light dull yellowish : all four tentacles 

 and head of a dull brick red colour. 



Shell elongate, cylindrical, thin and shining, semitransparent, 

 slightly opalescent, smooth, but with a few slight irregular 

 wrinkles in the line of growth : cpiJerinis \ery thin : whorls 5^, 

 unsymmetrical, the body whorl very oblique, narrow in front, 

 very broad and flattened behind aperture : penultimate ivhorl 

 very broad and oblique, forming a large hump on the left side 

 of the shell ; remaining whorls small and compressed ; the 

 nucleus is rounded and placed on the right side of the shell, 

 suture deep, very oblique, crossed by numerous short promi- 

 nent plicte ; mouth oblong, longer than broad, rounded in front, 

 squarish behind : lips almost parallel, slightly curved, thickened 

 and a little everted, forming a smooth rounded rim, connected 

 by a slight callus : umbilicus small, shallow, partly concealed by 

 the inner lip. 



