290 TESTACEOUS MOLLUSCA. 



S. Candidus. Lam. 4. — Chenu, II. C. Spond. t. 24, /. 4.— -Sow. 

 Thes. Conch. 1, p. 429, t. 84, /. 3, 4, 5. Kather small, white or 

 tinged with red, subfasciated at the beaks with smoke-coloured semi- 

 zones ; surface not ribbed, but roughened by very numerous elevated 

 striae, which are subimbricated by crowded simple scales of an 

 abbreviated lingulate form ; interstices adorned with close-set ele- 

 vated striulae, which are minutely and obsoletely squamiferous. 

 Var. The scales larger, less numerous, and more erect; the inter- 

 stices very finely striated. 2^. Lord Hood's I. 



S. Foliaceus, Ch. 7, p. 85, /. 472, 3. — S. Costatus, Lam. 6. — 

 Chenu, II. C. Spon. t. 22. — S. Spathuliferus, E. t. 191,/. 7. — Beeve, 

 C. S. 1. 119,/. 9.— (Kn. 1, t. 9,/. 2).— S. Petrosilenum, Sow. Th. 1, 

 419, Spon. f. 6, 8, 9, 10, 49. Solid, in the more characteristic 

 examples purplish red, with the foliations tinged with that hue, and 

 the armed ribs white. Surface usually shagreened ; the ribs strong 

 and prominent, the 5 or 6 principal of them foliated with large, 

 coarse and distant lamina?, which, although only of moderate length 

 and broadly palmated in the more typical specimens, appear some- 

 times (in large shells chiefly) to be simply spathulate from being 

 much elongated, but almost always evince a disposition to branch 

 out at their apices. The unarmed interstitial costae are rarely more 

 than two in number, since, upon the appearance of a third, one of 

 the grooves becomes filled up near the margin with white laminae 

 forming an incipient rib. Var. Of an uniform orange tint; the 

 unarmed costae almost obsolete. Var. (Costatus, Lam.). The aculea- 

 tion composed of very large distant strong and elongated spines ; 

 the ribs subbifid. Var. ? Of an uniform pink ; aculeation as in the 

 preceding, but the unarmed ribs narrower and squamiferous. The 

 minute shagreening, which even pervades the ribs in very perfect 

 examples, in the stunted palmiferous ones becomes almost obsolete. 

 There are neither interstitial raised stri<z nor fine costellce. 6. 

 Mauritius. 



S. Variegatus. Ch. 7, /. 464. — Lam. l.—^Chenu, II. C. Spon. 

 t. 10, /. 1, 3.— Sow. Th. 1, p. 425, t. 85, /. 14, 15. Small, solid, 

 white, with very fine zigzag lines of rufous chocolate diffused over 

 the surface. Ribs, in the more typical examples, coarse, rather far 

 apart, and by no means numerous ; (about) the 8 principal of them 

 guarded with strong and rather distant spathulate spines ; the 

 intermediate ones unarmed. Var. The aculeations simply spinous : 

 only 4 or 5 principal ribs : colouring as in type, except that the 

 surface is more or less tinged with orange near the beaks. Var. 

 The aculeations elongated and simply spathulate ; principal ribs 

 about 5 in number ; white, tinged with chocolate in the intervals of 

 the ribs. 2£. Amboyna. 



