Bainhridge, Ga., and of Alum Bluff, Fla. 253 



anterior regions nearer M. bella ; length 12*5 mm . 10. Spines of 

 the shoulder usually 9, reaching 13 on a whorl, variable from 

 short and blunt to larger and more acute, but not normally so 

 acute or with such sharp lateral edges as in the type of M. sub- 

 coronata ; the area between the angle of the shoulder and the 

 suture is more inclined. 11. Maximum length 37 mm , suture just 

 beneath the angle of the shoulder of the preceding whorl, area 

 anterior to the suture gently concave and then rounding into the 

 body, the earlier whorls may be distinctly nodulose, but the 

 nodules usually become obsolete in the last whorl. Spiral striae 

 present below the body, at times also visible above the rounded 

 angle of the shoulder. The smaller shells with obsolete nodules 

 have the general appearance of Bulbifusus. In the Chattahoo- 

 chee occurs a species 45 mm long, with acute spines along the 

 shoulder, 9 or more on a whorl. 12. Spire very low, whorls 

 keeled, suture applied on or just beneath the keel, shoulder 

 flattish, slightly concave, keel strongly angulate, nodulose, or 

 wavy or the last whorl without distinct tuberculation ; length 

 28 mm . 13. Canal in mature specimens strongly constricted at 

 junction with aperture, more open in immature ones ; lirse 6 

 to 7 ; plications 2, oftener obsolete ; varices narrow, varying to 

 more acate, the alternate ones almost wing-like, resembling 

 Triton. 14. Near Nassa triviltata, Say, with about 15 ribs, 

 crossed by coarse striations which are distinct below, obsolete on 

 the body, and which give rise to a single series of course nodules 

 just below the suture. 15. Spire a little less elevated. 16. 

 Length 18 mm , width 10 mm ; spire more rapidly tapering, varices 4, 

 triangularly pointed but hardly spinous above, ridges running 

 thence to the sutures above and below, and to the preced- 

 ing tube. The intermediate tubes in our specimens rise so 

 moderately above the angle of the shoulder as hardly to be 

 more than apertures, not elongated tubes ; this may be due 

 to wear. 17. Length I7 mm , width 6 mm , 7 or 8 whorls below 

 the nucleus, 12 strong' ribs below, strongest posteriorly, 

 crossed by five distinct striae between the sutures. 18. Vary- 

 ing towards subgrundifera, Dall, with which it is connected 

 by intermediate forms. 19. A distinct large quite rapidly 

 tapering species, with a strong basal (anterior) and an almost 

 equal strong medial, rounded spiral rib, the intermediate portions 

 strongly constricted, the whole ornamented by fine close spiral 

 striae. 20. Very variable. 21. A fine striation between the per- 

 ipheral keel and the spiral above, as well as below ; in addition to 

 the last there are below, first a narrower spiral, then four of 

 nearly equal size, and finally the abruptly broader umbilical car- 

 ina. 22. Low narrow spirally radiating ribs, becoming obsolete 

 towards the apex, curving towards the right below, crossed ob- 

 liquely by close distinct radiating striae. 23. A small form. 24. 

 Diameter 8*o mm , spire lower, upper surface more flattened, pro- 

 ducing a less regularly rounded periphery. 25. Length 16'8 mm , 

 width i-2 mm , height 10 mm , with about 70 radiating striae at the 



