MOLLUSCA OF PORTO RICO. 
507 
Systematic catalogue of the molhusks of Porto Rico — Continued. 
Family Rissoida:. 
Genus Rissoa Freminville. 
Rissoa epi/tna Dali & Simpson. 
Rissoa portoricana Dali & Simpson. 
Genus Rissoina d’Orbigny. 
Rissoina decussata Montagu. 
Rissoina browniana d’Orbigny. 
Rissoina chesnelii Michaud. 
Rissoina cancellata Philippi. 
Subfamily Hydrobiin a:. 
Genus Potamopyrgus Stiiiipson. 
Potamopyrgus coronatus Pfeiffer. 
Potamopyrgus coronatus var. crystallinus 
Shuttleworth. 
Family Cyclopiiorida. 
Genus Megalomastoma Guilding. 
Megalomastoma croceum Gmelin. 
Megalomastoma croceum var. curtum Dali 
& Simpson. 
M egalom astom a hja Imarsoni Pf e i ffe r. 
Megalomastoma verruculosvm Slnittlew. 
Family Cyclostomatidas. 
Genus Ciioanopoma Pfeiffer. 
Choanopoma decussatum Lamarck. 
Ciioanopoma senticosum Shuttleworth. 
Chocmopoma sulculosum Pfeiffer. 
Genus Cistula Gray. 
Vistula riisei Pfeiffer. 
Cistula aguadillensis Pfeiffer. 
Cistula lineolata Lamarck. 
Genus Ciiondropoma Pfeiffer. 
Chondropoma terebra Pfeiffer. 
Ciiondropoma blauneri Shuttleworth. 
Chondropoma swifti Shuttleworth. 
Ciiondropoma newtoni Shuttleworth. 
Family Truncatellida. 
Genus Truncatella Risso. 
Truncatella caribceensis Sower by. 
Truncatella subcylindrica .Lin me us. 
Trim catella pulchella Pf e i ff er . 
Truncatella clathrus Lowe. 
Family Calyptraada;. 
Genus Cheilea Modeer. 
Clieilea equestris Linnaeus. 
Genus Calyptraa Lamarck. 
Calyptroea candeana d’Orbigny. 
Genus Crepidula Lamarck. 
Crepidula aculecda Gmelin. 
Crepidula riisei Dunker. 
Crepidula protea d’Orbigny. 
Family Amaetheida. 
Genus Amalthea Schumacher. 
Amalthea antiquata Linnaeus. 
Amalthea subrufa Lamarck. 
Family Xenophorida. 
Genus Xenophora Fischer de Waldheim. 
Nenophora caribcea Petit. 
Family Naticida. 
Genus Natica Scopoli. 
Natica canrena (Linnaeus) auctorum. 
Natica sagraiana d’Orbigny. 
Section Stigmaueax Morch. 
Natica sulcata Born. 
Genus Polinices Montfort. 
Subgenus Payraudeautia Bucquoy, 
Dautzenberg & Dollfus. 
Polinices nubila Dali. 
Subgenus Mamilea Schumacher. 
Polinices uberina d’Orbigny. 
Polinices lactea, Guilding. 
Polinices mamillaris Lamarck. 
Genus Sigaretus Lamarck. 
Sigaretus martinianus Philippi. 
Superfamily Docoglossa. 
Family Acmaida. 
Genus Acmaa Eschscholtz. 
Acmcea candeana d’Orbigny. 
Acmcea punctulata Gmelin . 
Acm cea punct ulata var. pulcherrima Guil- 
ding. 
Acmcea leucopleura Gmelin. 
Superfamily Rhipidoglossa. 
Family Cocculinida. 
Genus Cocculina Dali. 
Cocculina portoricensis Dali & Simpson. 
