EAST COAST MARINE SHELLS 



87 



GENUS NISO Risso 1826 



Shell deeply umblllcated, many 

 whorled, apex acute, last whorl angulated 

 at periphery, operculiim present. 



NISO INTERRUPTA Sowerby. A white, polished 

 shell, often spotted upon the varices. A 

 narrow band at the suture and periphery is 

 usually characteristic. The varieties in- 

 clude one which is tri-colored. Length 

 19 mm. A variety is shown on PI. 65. 



PI. 33, Fig. 17 



PI. 65, Fig. 10 (v.aegles Sby.) 



Cape Hatteras, North Carolina to 



Gulf of Mexico 



NISO SPLENDIDULA Sowerby. Surface smooth, 

 whitish, highly polished; brown banded and 

 sometimes spotted in center of whorl, also 

 above and below suture. There are broad 

 zones of yellow in ^he middle of the early 

 whorls and both above and below the periph- 

 ery on body whorl. Length 1-1.5 inches. 



The specimen figured was taken by 

 the U. S. Fish Commission in 111 fathoms, 

 mud, between the Mississippi Delta and 

 Cedar Key. 



PI. 33, Fig. 16 



Off Cape Fear, North Carolina to 



Gulf of Mexico 



Family Pyramidellidae 



GENUS PYRAMIDELLA Lamarck 1799 



Distinguished by an elevated shell 

 with sharp-pointed spire and numerous 

 whorls; columella straight, with strong 

 spiral plications; operculum horny, semi- 

 circular, notched to fit plaits on columel- 

 la. 



PYRAMIDELLA CRENULATA Holmes. Suture dis- 

 tinctly crenulated; shell rarely light col- 

 lored; columella brown and plaits on the 

 same dark, even in pale specimens. 



Animal pale, tentacles flat, black 

 eyes close together; movements sluggish. 

 Length 14 mm. 



On the west coast of Florida it 

 lives in from low water to 2 fathoms and 

 prefers seaweed or muddy flats. 



PI. 33, Fig. 8 



South Carolina to west Florida; 



West Indies 



PYRAMIDELLA DOLABRATA Linnl. A smooth white 

 shell with three to four chestnut spiral 

 lines on body whorl and two on upper whorls; 

 outer lip often toothed inside. Length 

 1 inch. 



A very distinct and striking shell 

 on account of its shining surface. It is 

 quite frequent in the Bahamas and probably 

 lives among the Florida Keys. Dead shells 

 are sometimes found on the mainland beaches. 



PI. 34, Fig. 18 



Southern Florida and West Indies 



PYRAMIDELLA CANDIDA Morch. Shell pure 

 white, sometimes with an opaque white spi- 

 ral line on middle of whorl and one to two 

 small teeth in throat. Both toothed and 

 toothless individuals occur, possibly on 

 account of local influences. Length 7 mm. 



Dr. Rush dredged this shell at 

 6 fathoms in Turtle Harbor, Florida; the 

 writer off Tiger Key, Florida. It extends 

 to a known depth of 200 fathoms. Fresh dead 

 specimens have been taken on the beaches 

 at various points. 



PI. 34, Fig. 7 



North Carolina to Gulf of Mexico 



and West Indies 



PYRAMIDELLA FUSCA C. B. Adams. Shell light 

 brown, semitranslucent; sutures well marked; 

 base inflated; aperture large and ear- 

 shaped, outer lip thin; columella slender, 

 reflected portion forming narrow umbilicus; 

 oblique fold below insertion of columella; 

 operculum very thin. Length 5.5 mm. 



PI. 34, Fig. 21 



PI. 71, Fig. 15 



Prince Edward Island to Florida 



PYRAMIDELLA PRODUCTA C. B. Adams. Shell 

 light yellowish brown, translucent, suture 

 well impressed, periphery of last whorl 

 well rounded; outer lip thin; columella ob- 

 lique, twisted and with a strong fold an- 

 terior to its insertion. Length 5.1 mm. 



PI. 34, Fig. 15 



PI. 71, Fig. 13 



Massachusetts Bay to New Jersey 



PYRAMIDELLA WINKLEYI Bartsch. Shell semi- 

 translucent, light yellow; whorls eight, 

 the postnuclear ones moderately rounded 

 with summits marked by growth lines and fine 

 microscopic striations; periphery and base 

 of final whorl somewhat inflated; aperture 



