228 ASTRALIUM. 



A. HELiOTRoriUM Martyn, 1784. PL 56, fig. 87. 



Shell large, depressed-conic, below widely umbilicate and concave, 

 spire dome-shaped, of 5 convex whorls; suture rendered zigzui: by 

 the prominent compressed triangular recurved vaulted spines which 

 arm the acutely carinated periphery; whorls above and below with 

 numerous spiral series of granules ; umbilicus wide, deep, coarsely 

 obliquely striate within ; aperture transversely oval, oblique, pearly 

 within, peristome continuous; columella slightly dilated, impinging 

 upon the umbilicus; color brownish or purplish above, light below. 



Alt. 50-60, diarn. 100-120 mill. 



New Zealand ; Hauraki Gulf, Foveaux Sts., Cook's Sts., Bay of 

 Tasmania. 



Operculurn (pi. 59, figs. 5, 6) oval, with excentric nucleus ; outside 

 smooth, obsoletely unicostate. 



The synonyms are. Trochus solaria i>i imperalis etc. Chemnitz, T. 

 imperialis GmeL, and of most authors, Imperator aureolatus Mont- 

 fort, and Guildfordia heliophorus Gray. 



This large handsome species was brought to Europe for the first 

 time by the famous Captain Cook. 



Subgenus GUII/DFORDIA Gray, 1850. 



Shell Avheel-shaped, imperforate ; low-conic and granulose above, 

 convex below, periphery armed with long slender radiating .spines, 

 which are concealed at the sutures ; operculum fiat, with a snbobso- 

 lete arcuate rib outside. 



Japonic Province. 



A. TEIUMPHANS Phil., 1841. PL 58, figs. 67, 68. 



Shell low-conic, imperforate, metallic brownish-purple above, 

 nearly white below ; whorls 6, slightly convex above ; body-whorl 

 armed around the carinate periphery with long slender closed tubu- 

 lar radiating spines, about eight in number on the body-whorl, 

 and which are reabsorbed as the growth advances leaving only short 

 stumps to festoon the sutures ; upper surface with close revolving 

 series generally eight to ten on the last whorl of minute laterally 

 compressed granules; base slightly convex, usually with a marginal 

 row of granules, and several rows surrounding the central callus ; 

 aperture transversely ovate, angulate and channelled at peripheral 

 carina, iridescent within ; peristome sinuous above ; umbilical re- 



