MURICIDAE 157 



Urosalpiiix tampaeiisis Conrad PI. 31, fig. 221 



Alt. to 25 mm. Shell brownish or cinereous, general features of 

 U. perrugata; spire of four whorls below nucleus; about 10 longi- 

 tudinal ribs, strong overlying spiral cords on body whorl below peri- 

 phery, two on whorls of spire; shoulder of whorls without spirals, 

 sculpture is well elevated with excavated spaces between axial ribs 

 and revolving cords; outer lip deeply crenate. 



Littoral region to about one fathom. 



Genus THAIS Roding, 1798 



Subgenus STRAMONITA Schumacher, 1817 



Thais liaemastoma^se floridaiia (Conrad) PI. 50, fig. 343 



Alt., 46 mm.; diam., 24 mm. Shell solid, elongate, greyish white 

 with brown markings; six or seven moderately rounded whorls, 

 spirally sculptured with fine white lines, sixth or seventh line being 

 wider; shoulder of whorls smooth or slightly angled, with or with- 

 out two rows of small tubercles; suture faint and irregular; aper- 

 ture about half the length of shell, nearly oval; outer lip crenulated, 

 with brown lines extending into the opening, inner lip heavily 

 callused and glazed; umbilicus almost closed; anal canal short and 

 definite, margined with a heavy ridge; operculum corneous, dark 

 brown. 



Thais are carnivorous, feeding upon chitons and mussels. They 

 often attack oyster beds and become a menace. The adult exudes a 

 milky froth when disturbed which quickly turns to a deep purple 

 and was used by the ancients to dye the cloth for royal robes. Aside 

 from the dyeing qualities of this substance, it is poisonous and 

 serves to immobilize the victim for the next meal. 



Family COLUBKARIIDAE 



The mollusks of this family were formerly included among the 

 Tritonidae. Distribution of its genera is through temperate and warm 

 seas. 



The shells are fusiform, spire elongate, long oval aperture, with 

 a short recurved canal. 



-*6 Lat., Thais, wife of Ptolemaerus I of Egypt; hacma, blood; stoma, 

 mouth. 



