146 



I do not place much value on the outward form, sculpture, and size 

 of these Oyclotus, and, wanting the opercula, regard the classificatiou 

 of them as very difficult ; I will, however, proceed to the more particular 

 description of each species and variety as I find them in my own 

 private cabinet, taking them in the order already mentioned. 



§1- 



C. coRRUGATus, Sow. Proc. z. s. 1843, pp. 29, 30. 



Sowerby's entire description is, " C. testą orbiculata, subdepressa, 

 crassiuscula, albida, apice rufescente; epidermide tenui, fusca, induta; 

 spirula subprominula, acuminatiuscula ; anfractibns quinque, rotun- 

 datis, transversim striatis et corrugatis ; sutiira distincta, apertura 

 circulari, subeffusa, superne angulata et in canalem inconspicuam 

 desinente ; peritremate tenuiusculo, margine acutiusculo, latere um- 

 bilicaU incrassato ; umbiHco magno, margine crenulato, intns trans- 

 versim striato. Operculo testaceo, extvis lamina elevata, convoluta, 

 intus corneo, polito." 



C. CORRUGATUS, Pfr. Cat. Phan. p. 13. 



Shell subturbinate-depressed, solid, regularly all over angularly 

 vvrinkled, white, 'vvith a deciduous fuhid epidermis ; spire short, 

 reddish, rather acuminate ; ivhorls 5, convex, the lašt one cylindrical, 

 nearly flat beneath, with a yiodnlous ridye around the umbilicus, which 

 is opėn, and of a middle size ; aperture a little oblique, nearly circnlar, 

 with a slight angle above, inside whitish ; peristome straight, blunt ; 

 its margins joined into an angle, which often is doubled ; right mar- 

 gin slightly sinuate ; left margin shortly affised to the penult whorl. 

 Operculum concave externally, with 9 very narrow whorls, the mar- 

 gin of which is dilated into broad, spirai, raised, somewhat espanded 

 laminfe. Height 14, greatest breadth 22, least breadth 19 mill. — Cat. 

 Phan. p. 13. 



C. CORRUGATUS, Chitty. 



The shell I adopt as C corrugatus I describe as " depressed-tur- 

 binate : colour blueish-white, with an epidermis of rich red-brown 

 and vellowish-brown ; just belowthe suture and apex, rich red-brown; 

 salm'on-colour tinge within the aperture. Scidpture, the 3f upper 

 whorls, excepting the nuclear apex, with the lines of growth strongly 

 but finely defiued, without wrinkles. Thence the lines of grovvth 

 become coarser and coarser throughout the remainder ; coarser and 

 coarser wrinkles diagonally from right above to left below on the 

 penult whorl, the wrinkles gradually assuming a zigzag form, till 

 they become very coarse at the periphery of the lašt whorl, and then 

 eccentric cur^ilinear grooves which terminate and are deepest, but 

 are not tooth-marked at the umbilical keel, which is well raised, 

 theHerminating fourth part of the lašt whorl becoming compara- 

 tiveiy sniooth. Spire, moderately elevated, vnūi convex outlines. 

 Whorls, aį, moderately rounded, rather flattened above, and spread- 

 ing below, with moderate suture ; the terminai half of the lašt 



