96 



EAST COAST MARINE SHELLS 



bottom of a container. All over the world, 

 in warm seas, this species occurs. 



PI. 37, Fig. 10 



Off Martha's Vineyard to the West 



Indies 



GENDS ALABA H. and A. Adams 1853 



Shell elongated, pointed; many 

 rounded whorls; irregularly placed varices; 

 aperture oval, lip barely thickened, smooth 

 inside. 



ALABA TERVARICOSA Adams. Whorls about 

 thirteen, gradually increasing, often bulg- 

 ing and giving shell a distorted appear- 

 ance; first five to six whorls darker, re- 

 mainder with delicate revolving threads 

 which are crossed by growth lines; several 

 varices on each whorl. Length 6 mm. 



This beautiful little shell is 

 often very thin, the interior partitions 

 showing through the shell. It is rather 

 frequent among drift along the beaches of 

 Florida. 



PI. 37, Fig. 11 



Tampa Bay; Southern Florida; West 



Indies 



Family Skeneldae 



Shell minute or small, depressed, 

 few whorled; peristome continuous. Animal 

 similar to Rissoa. Found living under 

 stones, on algae and among roots of Coral- 

 lina. 



GENUS SKENEA Fleming 1828 



Shell nearly discoidal, few ^orled. 



SKENEA PLANORBIS Fabricius. Shell very 

 minute, thin, opaque, brown or yellow in 

 color; spire a little elevated; whorls four, 

 suture deep; umbilicus wide. Diameter 1.4 

 mm. 



PI. 71. Fig. 18 



Greenland to Florida; Europe 



GENDS ADEORBIS Wood 1842 



Shell depressed, base flattened, 

 white and often subtranslucent; aperture 

 rounded, lip simple. Operculum corneous, 

 smooth externally, the spire visible in 

 middle of inner side. 



ADEORBIS BEADI Fischer. Shell white, acute- 

 ly keeled at periphery, an equally strong 

 keel below; about six fairly strong spiral 

 ribs above periphery on last whorl with 

 three to four much finer ones between these; 

 upper surface diill but ribs usually shin- 

 ing; nucleus glassy; umbilicus wide and 

 deep; base shining and with numerous fine 

 spiral lines. Breadth 9 mm. 



Beautiful examples have been taken 

 at Sanibel and Palm Beach, Florida, upon 

 the beaches. It is a rather rare shell. 



PI. 44, Fig. 9 



Cedar Keys, west Florida to West 



Indies; Palm Beach, Florida 



ADEORBIS SUPRANITIDDS Wood. A small edi- 

 tion of the preceding species; upper sur- 

 face more shining, also an additional keel 

 near the lombllicus. Breadth 2.5 mm. Depth 

 range 15-25 fathoms but also sometimes 

 found on the beaches. 



PI. 65, Figs. 7, 7a 



North Carolina to Gulf of Mexico 



Family Architectonicldae (Solarlidae ) 



Shell widely and remarkably umblll- 

 cated, the umbilicus bordered with a crenu- 

 lated keel; solid, depressed; nucleus 

 sinistral, oblique and with sculptured 

 whorls; columella vertical; operculum horny 

 and with a tubercle upon Its inner side. 



GENUS ARCHITECTONICA Roeding 1798 

 Solarium (SUNDIAL) 



ARCHITECTONICA BISULCATA Orblgny. Double- 

 furrowed Dial, Shell small, umbilicus wide; 

 spire hardly raised; whorls flat and with 

 revolving grooves cut by furrows into 

 granules, the rows nearest the suture being 

 the strongest, also two rows on periphery; 

 about same sculpture on base. Color dirty 

 white. Diameter 10 mm. Range 55-440 fath- 

 oms. 



All of the four species described 

 have been taken upon the Florida beaches. 



PI. 37, Fig. 1 



•^•ape Cod to West Indies 



ARCHITECTONICA GRANULATA Lamarck (S, verru- 

 cosum Phil.). Granulated Sundial. Whorls 

 spirally sulcate, four prominent sulcations 

 and traces of others; growth lines of spire 

 breaking surface into granules; ximbilicus 



