186 Marine Shells of the Western Coast of Florida 



rounded nodules, that give to the entire surface of the shell a decidedly 

 granulose effect. This type of sculpture also characterizes the base where 

 the spirals are a little more distantly spaced and the nodulation less pro- 

 nounced. Columella short and stubby, marked by rather rough oblique 

 lines. Aperture oval, strongly channeled anteriorly with a deep sinus im- 

 mediately below the summit, whose outer edge is somewhat thickened and 

 reflected. Anterior to the sinus the outer lip is produced into a clawlike 

 element. Inner lip appressed to the columella as a callus extending over 

 the parietal wall. 3*^ 



Sandbars in shallow water. 



Genus STELLATOMA Bartsch and Rehder, 1939 

 Stelliitoina-'^* stellata (Stearns) PI. 38, fig. 268A 



Alt., 7 mm., spire a little less than half of altitude. Shell elongate, 

 ovate, turreted; color yellowish, usually banded about sutures and 

 body whorl and tinted about outer lip and columella with violet- 

 brown; about six whorls; postnuclear whorls with straight shoulder 

 sloping to angled keel, convex below, sutures distinct; about 11 

 axial ribs extending to base of body whorl, spiral threads below 

 and fine spiral striations in intercostal spaces; aperture semiovate; 

 anterior canal extremely short; outer lip thickened, with posterior 

 varix and a small denticle at anterior angle of the shallow, sub- 

 sutural posterior sinus; columella with one obscure internal fold. 



Sandy station from shallow water to three fathoms. 



Genus PYRGOCTTHARA Woodring, 1928 



Pyrgocj thiiras^s hemphilli Bartsch and Rehder PI. 38, fig. 269 



Shell small, elongate-ovate, varying in ground color from chestnut- 

 brown to wax yellow, usually with a pale zone at the angle of the shoul- 

 der. The outer lip and base of the columella may be orange or dark 

 purplish orange. Nuclear whorls slender, the first 1.5 smooth, succeeded 

 by about two-tenths of a turn that shows slender, retractively curved, 

 axial riblets, which in turn are followed by the postnuclear sculpture. 

 Postnuclear whorls moderately well rounded, appressed at the summit. 

 The postnuclear whorls are marked by very strong, sinuous axial ribs, 

 which taper at the summit and evanesce on the columella. Of these ribs 

 10 occur on the first and second, 9 on the third and fourth, 10 on the 

 fifth, and 9 on the last. In addition to the axial ribs, the entire surface 

 of the shell is marked by microscopic incremental lines. The spiral sculp- 

 ture consists of a low, rounded, obsolete keel, which occupies the middle 

 of the turns on the first four whorls but falls a little posterior to this 

 on the rest of the shell. This produces a decided shoulder on the whorls. 



343 Bartsch and Rehder: Proc. U.S. National Museum, vol. 87, No. 3070. 

 3** Lat., Stella, star; Gr., tomos section. 

 ^"^•^ Gr., pyrgos, tower. 



