62 



CONCHOLOGIA CESTRICA. 



DIAGRAM OF THE SUB-FAMILIES, GENERA, SUB-GENERA, AND 

 SPECIES, OF THE FAMILY LIMNAEID^E. 



FAMILY. 



LIMNAEIDjE. 



SUB-FAMILY. 



LIMNAEIN.E. 



PHYSIN^E. 



PLANORBIN^E. 



ANCYLIN^E. 



Genus LIMN^A, LAMARCK, 1799. 



Animal of lAnmcea desidiosa. [W. G. B.j 

 Fig, 116, 



Shell, dextral, spiral, oblong, or ovate, translucent, 

 horn color ; spire acute ; last whorl ventricose ; aperture 

 large, wide, rounded below; inner lip with an oblique 

 fold ; outer lip simple. 



Animal, tentacles flattened, triangular; mantle thick- 

 ened in front ; foot short, rounded. 



Sub-genus RADIX, MONTFORT, 1810. 



Shell, sub-ovate, ventricose; aperture more than half 

 the length of the shell, greatly expanded. 



