76 CALIFOKNIA ACADEMY OF SCIENCES. 



MOLLUSC A (Continued). 



Genus Semele 165 



111. decisa CoxR-iD 165 



112. pulchra SowERBY 166 



113. pulchra Sowerbt, var. montereyi, var. hot 166 



Genus Cumiugia Soweebt 167 



114. californica Conrad 167 



Family XXX II. Psammobiidce 167 



Genus Psammobia (Lamarck) Bowdich 167 



Subgenus Psammobia, s. s 167 



115. (P.) edeutula Gabb 168 



Genus Sanguiuolaria Lamarck 168 



Section Nuttallia Dall 168 



116. (N.) nuttalli Conrad 168 



Genus Tagelns Gray 169 



117. californianus Conrad 169 



Family XXXIII. Donacidce 169 



Genus Donax (Linne) Lamarck 169 



118. californica Conrad 170 



119. laevigata Deshayes 170 



SUPERFAMILT iiOLEXACEA, 171 



Family XXXI V. Solenidte 171 



Genus Solen Linne 171 



120. rosaceus Carpenter 171 



121. sicarius Gould 172 



Genus Siliqua Megerle 172 



122. lucida Conrad 172 



123. patula D:xoN, var. uuttaUi Conrad 173 



SUPERFAMILT MACTRACEA 174 



Family XXX V. Maclridw 174 



Subfamily Maclrince 174 



Genus Mactra Linne 174 



124. californica Conrad 174 



125. exoleta Gray 175 



126. hemphilli Dall 175 



Subgenus Spisula Gray 175 



127. (S.) catilliformis Conkad 176 



128. (S.) falcata Gocld 176 



Subfamily Pleropsidina 177 



Genus Labiosa (Schmidt) MSller 177 



Subgenus Kieta Gray 177 



129. (R.) undulata Gould 177 



Subfamily Lulrariince 178 



Genus Tresus Gray 178 



130. nuttaUi Conrad 178 



SUPERFAMILY MTACEA 179 



Family XXX VI. Myacidce 179 



Genus Platyodon Conrad 179 



131. caucellatus Conrad 179 



Genns Cryptomya Conr.\d 179 



132. californica Conrad 180 



Family XXX VII. Corbulidce 180 



Genus Corbula (Bruguiere) La.marck 180 



133. luteola Carpenter 181 



GeuuB Nesra Gray 181 



134. pectiuata Carpenter 181 



Family XXX VIII. Saxicavida; 182 



Genus Panopea Menard 182 



135. geuerosa Gould 182 



