13 



from the eyes, disappearing under the shell, black ; a gamboge 

 colored vitta is visible through that part of the shell which is 

 opposed to the mouth. 

 ><■ Polyphemus glans. — This shell furnished De Montfort with . 

 the type of his genus Polyphemus ,; he refers to Bruquiere as 

 the first describer of it, under the name of Bulimus glans in the 

 Encycl. Method. The animal has not been described, but wo are 

 informed that it lives in the immense marshes, formed by the over- 

 flow of the great rivers that water the vast country of Louisiana. 

 In the sea islands of Georgia, we found them numerous in the 

 marshy districts immediately behind the sand-hills of the coast, in 

 Florida in similar situations, and also on the Oyster-Shell Ham- 

 mocks, and generally in such situations as are tenanted by Succinea 

 campestris. The color of the shell on the spire is chestnut brown, 

 which gradually and very perceptibly becomes paler to the aper- 

 ture ; aperture occupying about half the length of the shell. On 

 elevated situations they are small, almost transparent, and of a 

 fragile consistence. It is only in low, marshy situations that they 

 attain their greatest size. 



Length two inches and two-fifths, breadth one inch nearly. 



Animal elongated, as long again as the shell, granulated, tenta- 

 cula four, superior ones oculiferous, abruptly deflected at tip, be- 

 yond the eyes ; inferior ones much shorter and deflected at tip ; 

 lips beneath the tentacula elongated, palpiform, almost as long as 

 the superior tentacula, retractile, generally more or less recurved, 

 compressed, attenuated, and acute at tip, and forming a considera- 

 ble interval between their prominent bases. 



When the animal is in motion, the elongated lips are used as 

 tentacula to feel the way. 



Genus Olygyra. 

 Shell rounded ; aperture longer than broad, semiorbicular, 

 emarginated by a projection of the penultimate whorl ; external 

 lip reflected; pillar-lip with obsolete calcareous deposit; umbilicus 

 none ; columella slightly angulated at base. 



Animal terrestrial, operculated ; tentacula two, filiform ; eyes 

 prominent, placed at the external base of the tentacula ; rostrum 

 bilabiated at tip, shorter than the tentacula ; foot simple. 

 (^ 0. ORBICULATA. — Shell subglobular ; spire not prominent, but 



