BY C. HBDLEY. 507 



SCALENOSTOMA STRIATUM, 11. sp. 



(Plate xxvi., figs. 15, 16, 17.) 



Shell conical, rather glossy, opaque and solid. Colour dead 

 white. N"o trace of epidermis. Whorls six, including two which 

 are apical, smooth and glossy. The initial one is as tall but 

 narrower than its follower, thus projecting as a style. The four 

 subsequent whorls are parted by an impressed suture, below 

 which they are slightly shelved, thence moderately rounded. 

 The last is abruptly angled, rather than keeled, at the periphery, 

 and rounded on the base. Sculpture : the adult whorls are 

 closely girt by numerous fine spiral threads, between which are 

 grooves of equal breadth and corresponding depth. These are 

 obliquely and irregularly crossed by fine and coarse growth lines. 

 An obscure varix occurs three-quarters of a whorl behind the 

 aperture. The aperture is oblique; in profile the lip is shown to 

 have a slight, much shallower than in the type, sinus below the 

 suture, thence it curves forward slightly to the periphery, whence 

 it slopes backward to the base. Aperture ovate, rounded below, 

 angled above, lip sharp; columella thickened, a little reflected, 

 deeply entering. Length 6-5, breadth 3-5 mm. — [No operculum. 

 J.B.] 



Hab. — Several specimens " found round the anus of a species of 

 Goniocidaris, dredged in 10 fathoms, sandy mud, Port Molle, 

 Queensland "; one specimen dredged in 25-30 fathoms off Darn- 

 ley I., Torres Straits (J. Brazier). 



Type to be presented to the Australian Museum. 



In this species another genus is added to the Australian fauna. 

 From all co-generic forms its few whorls, comparatively greater 

 breadth and sculpture, amply distinguish it. Another point of 

 interest is that it adds a genus to the list of parasites. 



The parasitic Gasteropoda are not many, and it is remarkable 

 that they have chosen their hosts from one class only, the Echi- 

 nodermata. No distinction was made by earlier writers between 



