76 CALIFOENIA ACADEMY OF SCIENCES. 



MOLLUSCA (Continued). 



Genus Semele 165 



111. decisa CoNR.\D 165 



1 12. pulchra Sowerey 166 



113. pulchra Sowerey, var. mouteieyi, var. uov 166 



Genus Cumiugia Sowerey 167 



1 14. californica Conrad 167 



Family XXXII. Psatnmohiidie.. . . 167 



GeuTis Psammobia (L.\marck) Bowmen 167 



Subgenus Psammobia, s. s 167 



115. (P.) eilentula Gabb 168 



Genus Sanguinolaria Lamarck 168 



Section Nuttallia Dall 168 



116. (N.) nuttalli Conrad 168 



Genus Tagelus Gray 169 



117. californianus Co.nrad 169 



Family XXX I II . Donacidm 169 



Genus Donax (Linne) Lamarck 169 



1 18. californica Conrad 170 



1 19. l^vigata Deshayes 170 



SUPERFAMIL Y SOLENACEA 171 



Family XXXIV. Solenidce 171 



Genus Solen Linne 171 



120. rosaceus Carpenter 171 



121. sicarius Gooi.D 172 



Genus Siliqua Megerle 172 



122. lucida Conrad 172 



123. patula Dixon, var. nuttalli Conrad 173 



SUPERFAMILY MACTRACEA 174 



Family XXX V. Maclridai 174 



Subfamily Mactrinte 174 



Genus Mactra Linne 174 



124. californica Conrad 174 



125. exoleta Gray 175 



126. hempbilli Dall 175 



Subgenus Spisula Gray 175 



127. (S.) catilliformis Conrad 176 



128. (S.) falcata Gould 176 



Subfamily Pieropsidince 177 



Genus Labiosa (Schmidt) Moller . . 177 



Subgenus Rseta Gray 177 



129. (R.) uudulata Gould 177 



Subfamily Lulrariiiiat 178 



Genus Tresus Gray 178 



130. nuttalli Conrad 178 



SUPERFAMILY MYACEA 179 



Family XXX VI. Myacidce 179 



Genus Platyodon Conrad 179 



131. cancellatus Conrad 179 



Genus Cryptomya Conrad 179 



132. californica Conrad 180 



Fainily XXX VII. Corhulidie 180 



Genus Corbula (BROoniiiRE) Lamarck 180 



133. hitcola Carpenter 181 



Genus Nesera Gray 181 



134. pectinata Carpenter 181 



Family XXX VIII. Saxicavidw. 182 



Genus Panopea Menard 182 



135. generosa Goold 182 



