CAECUM. 217 



Section II. Annulata. 

 C. SUBIMPRESSUM, Carp. PL 66, fig. 61. 



Rather solid, the annulations rounded, with subimpressed 

 interstices, septum mucronate, mucro small, obtuse, dorsal; 

 operculum concave. Length, '115 inches. 



Mazatlan to Cape St. Lucas, L. G. 



C. FLORIDANUM, Stimpson. PI. 66, fig. 62. 



Arcuate, solid, white, shining, with about 32 acute, elevated 

 annulations and much wider interstices, aperture a little oblique, 

 not contracted, septum obtusely mucronate, mucro dorsal. 



Florida. 

 C. PULCHELLUM, Stimpson. PI. 66, fig. 63. 



Somewhat solid, light brownish, adolescent stage graceful, 

 with distant few annulations, adult with about 25 rounded annu- 

 lations and more or less equal interstices, septum mamillate ; 

 operculum concave, with about 8 whorls. Length, ! inch. 



New Bedford, Mass. 

 C. FIRMATUM, C. B. Ad. PI. 67, fig. 66. 



Stout, young shell smooth, adult with 23-33 annulations, the 

 earlier ones more acute, then becoming subquadrate, interstices 

 also subquadrate, narrow, septum subangulate, the projection 

 short. Length, ! inch. 



Panama, Mazatlan, Todas Santos Bay, L. G. 



With this are to be united, according to Carpenter, G. ebur- 

 neum, C. diminutum (jun.), C. pygmseum. and C. monstrosum 

 (both adolescent), of C. B. Adams. 



C. QUADRATUM, Carp. PI. 67, fig. 67. 



Short, solid, with 12-20 quadrate annulations, and deep quad- 

 rate interstices, aperture subcontracted, septum mucronate, the 

 mucro small, narrow, subdextral. Length, '072 inch. Mazatlan. 



Yar. COMPACTUM, Carp. PL 67, fig. 68. 



Annulations large, planate, interstices small or evanescent. 



C. ELEGANTISSIMUM, Carp. PI. 67, fig. 69. 



Diaphanous, vitreous, shining, white, aperture slightly con- 

 tracted and oblique, young shell smooth, adolescent and adult 

 with 14 to 18 distant acute lirae, the interstices ve^ elegantly 

 arcuate ; septum submucronate and subungulate, the small apex 

 obtuse. Length, 1 inch. Teneriffe. 



