334 JOURNAL OF CONCHOLOGY, VOL. I4, NO. II, JULY, I915. 



Group D. 

 17. — 6". marisrubri Bolten. Museum Boltenianum, 1798, p. 194. 

 Conch. Cab., vii., pi. 44, fig. 460. 



{=dentati(s Chenu, Illust. Conchyl., p. 5, pi. 25, fig. i, 



pi 27, fig. 2). 

 (=aatleahis '^ow. Thes. Conch., pi. 85, figs, ir-13, 

 Conch. Icon., pi. 17, fig. 63). 

 Hab. : Mauritius (Sow.). Australia (Chenu). 



18. — 6". ambigims Chenu. Illust. Conchyl., p. 5, pi. 28, fig. i. 

 Hab. : American Seas (Chenu). 



19. — S. castus Reeve. Conch. Icon., pi. 12, fig. 47. Conch. Cab. 

 (2nd edit ), pi. 9, fig. 5. 



Hab. : Philippine Islands. 



Tlie type is a medium-sized specimen ; some specimens are much 

 larger, having somewhat the appearance of marisrubri. 



CrROUP E. 



20. — S. ]ivstr\x Bolten. Museum Boltenianum, p. 195. C'onch. 

 Cab., vii., pi. 45, fig. 470. Illust. Conchy)., pi. 28, figs. 2-4. 

 (^=radiaus Lk. Hist. Anim. Sans Vert., vi., p. 192). 

 (=aciileahts Bred. Proc. Zool. Soc, 1833, p. 5). 

 {^^ciliaiiis Sow. Thes. Conch., vol. i., pi. 89, fig. 52. 



Conch. Icon., fig. 4). 

 (^^nicobaricus Sow. Thes. Conch., pi. 88, fig. 48). 

 {-^=coccineMs Sow. & Reeve, non Lamk. Thes. Conch., 

 pi. 88, fig. 47. Conch. Icon., pi. 12, fig. 44). 

 Hab. : Nicobar and I'imor Islands (Chenu). Mauritius, on float- 

 ing pumice stone from eruption of Krakatoa, Sunda Straits (Robillard). 

 Lord Hood's Island (Cuming). 



Very variable in degree of spinosity, some specimens having very 

 numerous and closely-set spines, whilst others are in appearance 

 almost smooth. A large series from Mauritius varies from almost plain 

 white to specimens half covered on lower part with purple-brown. 



S. hystryx var. ocellatus Reeve. Conch. Icon., pi. 12, fig. 43. 



Hab. : Philippine Islands (Cuming). 



Somewhat similar specimens have been found at Mauritius on 

 floating pumice stone, but the spots are more numerous and the 

 ground-colour more reddish than the specimens collected by Cuming 

 at the Philippines. 



