Milneria minima Dall. Last Milner-shell. [Fig. 38.]
Aula (Nucula) casternsis Hinds. Camp Nut-shell. [Fig. 39.]
FRESH-WATER AND LAND SHELLS UNIVALVES
Physa heterostropha Say. Laguna stream. [Fig. 40.]
Physa occidentalis Tryon. Aliso Lake. [Fig. 41.]
Limnophysa palustris Mull. [Fig. 42.]
Planorbis (Helisoma) trivolvis Say. [Fig. 43.]
Helix aspera Mull. [Fig. 44.]
Epiphragmophora Sp. [Fig. 45.]
MARINE UNIVALVES