MITRELLA. 117 



rect. I have specimens of the original lot before me ; they do 

 not differ from unifazciata. The very short description given 

 by Lamarck of his C. unifasciaU* leaves little doubt that it WHH 

 intended for this species : it is said to have come from the Isle of 

 France, and has never been identified positively. I include also 

 C. ebenum, Phil., an un figured species from Magellan's Straits. 



C. ELECTROIDES, Reeve. PI. 47, fig. 44. 



Shell ovate, smooth, rather thin ; reddish fulvous, articulated 

 with white next the sutures. Length, 13 mill. 



Bay of Guayaquil. 

 C. INFUMATA, Crosse. PI. 47, fig. 45. 



Shell ovate-elongate, rather thick, smooth, not shining ; 

 chestnut-brown, with scarcely visible white maculations next 

 the suture. Length, 12 mill. 



So. Australia. 



Section IV. Mitrella, Ri?so 



Shell mitriform, smooth, with moderate spire; columella smooth 

 or with a few anterior rugosities ; outer lip smooth or crenulated 

 within. I unite with this group Astyris and Amycla (in part) of 

 H. and A. Adams. The principal species of the latter are true 

 Nax*&< and are described in vol. iv, 36, 37. 



( 1 . IDALINA, Duclos. PI. 47, figs. 46, 47. 



Shell smooth, polished, yellowish or rosy white, apex pink, 

 with a row of opaque white spots on the periphery, sqmetimes 

 shaded, and occasionally reappearing at the sutures of the upper 

 whorls. Length, 8* mill. 



St. Thomas, W. I. (Swift). 



Under a glass, the shell is sometimes covered with smooth, 

 rounded longitudinal ribs ; the outer lip appears to be smooth 

 within. C. gulttirosa, Duclos (fig. 47), is a larger shell according 

 to the figure given, but does not otherwise differ from a faded 

 state of C. idalina. 



C. MOLECULINA, Duclos. PL 47, figs. 48, 49. 



Shell white, with an open network of chestnut, and darker 

 chestnut curved markings near the suture, defining a sutural 

 band ; sometimes the surface is covered with chocolate, except 

 the sutural space and the defining markings. 



Habitat unknown. 



