104 



EAST COAST MARINE SHELLS 



Inside the Inlet at Palm Beach it 

 lives under stones, between tides, espe- 

 cially in May or June. Often hundreds of 

 individuals are gathered together under one 

 small stone. 



PI. 37, Fig. 8 



Southern Florida and West Indies 



PLANAXIS NUCLEUS Lamarck. Much larger than 

 the preceding; color dark reddish brown or 

 light chocolate, sometimes almost black 

 both inside and out; cut with widely spaced 

 grooves; notch at base well defined and 

 deep. Length 12 mm. 



Found at the same station as P. 

 llneatus but deep under piles of rock and 

 well above the low-tide mark. 



PI. 37, Fig. 7 



Southern Florida and West Indies 



Family Modulldae 



Shell umblllcate, solid, sculptured; 

 aperture rounded; columella with a sharp 

 tooth at base. 



GENUS MODULUS Gray 1842 and 1847 



MODULUS MODULUS Linne. Spire low, periph- 

 ery sharply keeled; last whorl descending 

 at aperture; strong ribs and less prominent 

 ridges upon surface; deep grooves between 

 five to eight ridges at base; inside of lips 

 with distinct ridges. Color white, spot- 

 ted with brown; at the base the color pat- 

 tern extending over the ribs. Diameter 

 15 mm. 



The animal has long cylindrical 

 tentacles with eyes placed at about one- 

 half their length. 



This species lives upon weeds in 

 shallow protected water and may easily be 

 observed with a water glass. It Is very 

 abundant in lower Biscayne Bay, Florida. 



PI. 37, Fig. 21 



North Carolina to West Indies 



MODULUS MODULUS FLORIDANUS Conrad. Instead 

 of the whorls being nearly flat as in the 

 preceding this variety has them somewhat 

 convex and radiately ribbed. 



North Carolina to Gulf Coast of 



Florida 



MODULUS ANGULATUS C. B. Adams (M. catenu- 

 latus Phllippi). Shell solid with a high, 

 Sharp-pointed spire; whorls flat or a lit- 



tle concave; base swollen, somewhat dug out 

 adjacent to the umbilicus; fine encircling 

 cords upon surface which cross the lines of 

 growth and form little knobs. Color gray 

 or brown, with touches of white on the ribs; 

 base lighter. Length 15 mm. 



This species also lives at Panama 

 and northward in Central America. 



PI. 38, Fig. 18 



Florida Keys and the West Indies 



Family Trlphoridae 



Shell minute, elongated, sinistral 

 (left handed), many whorled; aperture small, 

 canal short. 



In addition to the sinistral form 

 these shells are remarkable for their re- 

 tention of the larval characters when al- 

 most fully adult. The nucleus should be 

 carefully studied. 



GENUS TRIPHORA Deshayes 1824 



TRIPHORA DECORATA C. B. Adams. Shell white 

 with large brown spots; three equal rows of 

 beads and deep channels between; whorls 

 sixteen, suture deeply grooved. Length 14 

 mm. 



Key West, Florida and Gulf of Mex- 

 ico 



TRIPHORA PERVERSA NIGROCINCTA C. B. Adams. 

 Shell dark brown, whorls thirteen to fif- 

 teen; suture excavated; four rows of tuber- 

 cles upon body whorl, two to three ridges 

 below them; dark brown basal canal. Length 

 10 mm. Depth range 1-30 fathoms. 



PI. 38, Fig. 3 



Massachusetts to Florida 



TRIPHORA MELANURA C. B. Adams. Shell slen- 

 der, whorls about fourteen, with three re- 

 volving rows of nodules arranged in slight- 

 ly oblique rows; groove at suture the deep- 

 est; aperture small; canal short, inclining 

 a little to the right. Color white except 

 the dark brown apex. Length 5 mm. 



PI. 38, Fig. 4 



North Carolina to the West Indies 



TRIPHORA TURRIS-THOMAE Dlllwyn. Shell with 

 about sixteen whorls, slowly increasing; 

 suture indistinct; two revolving rows of 

 nodules, upper row whitish, the lower brown; 

 the two rows covering entire surface of 

 whorls and divided from each other by a 



