175 



88. nassula, Conrad. 



89. Niagarensis, Lea. 



90. Nickliniana, id. 



91. nitens, id. 



92. nodulosa, id. 



93. obovata, Say. 



94. obtusa, Lea. 



95. occata, Hinds. 



96. occidentalis, Lea. 



97. Ocooensis, id. 



98. ohvata, Conrad. 



99. ornata, Philippi. 



100. Papuensis, Q?<oy. 



101. perpiuguis, Hinds. 



102. picta, Hinds. 



103. pilula, Zea. 



104. plicatula, ^a 7 . 



105. Plutonis, Hinds. 



106. Potosiensis, Zea. 



107. prasinata, Conrad. 



108. prserosa, /Say. 



109. pugibs, Hinds. 



110. pyramidata, «?. 



111. Kangii, Deshayes. 



112. regularis, Lea. 



113. rufa, ia*. 



114. rugosa, id. 



115. salebrosa, Conrad. 



116. Sayii, Desliayes. 



117. scabra, Ferussac. 



118. scalaris, Wagner. 



119. seruicarinata, £ay. 



120. semigranosa, P/m7. 



121. setosa, Swainson. 



122. sordida, Zea. 



123. spinosa, z'a*. 



124. striatula, id. 



125. strigosa, z'a*. 



126. subcylindracea, id. 



127. subglobosa, Say. 



128. subsolida, Zea. 



129. subulata, Deshayes. 



130. sulcosa, Zee. 



131. Taitiana, id. 



132. tenebrosa, id. 



133. terebra, Philippi. 



134. terebralis, Zea. 



135. teres, w?. 



136. testudinaria, Phil. 



137. tirouri, Ferussac. 



138. torquata, Philippi. 



139. trilineata, /Say. 



140. Troostiana, Ze«. 



141. truncata, Lamarck. 



142. truncatula, id. 



143. tubereulata, Wagner. 



144. tubereulata, Zm. 



145. tympanorum, Zes/«. 



146. undulata, Say. 



147. uniformis, Quoy. 



148. variabilis, Benson. 



149. varicosa, Ward. 



150. veuusta, Zw. 



151. verrucosa, Hinds. 



152. vngata, Zea. 



153. Virginica, /Say. 



154. virgulata, Ferussac. 



155. viridis, Zea. 



156. Warderiana, id. 



157. Winterii, Philippi. 



158. zouata, /a*. 



Figures. 



Melania asperata. PI. 18. Pig. 97. Shell, illustrating the typical 

 form of the genus, with aperture entire. 



Melania spinosa. PI. 18. Pig. 98. Shell, illustrative of the Io sec- 

 tion of the genus, in which the aperture is attenuated at the base 

 into a canal. 



Genus 3. PALUDOMUS, Swainson. 



Animal ; similar to that of Melania. 



Shell ; ovate, somewhat ventricose ; spire short, sometimes de- 

 pressed, sometimes exserted ; columella a little excavated, ra- 

 ther broad, flat, entire at the base, rounded ; aperture large, 

 somewhat semicircular, slightly channelled at the upper part ; 

 lip simple. Epidermis olive, brown, or black. 



