1 78 Dr. P. P. Carpenter on new Forms of Mollusca 



recta, extus et intus rosacea; epidermide tenui, valde nitente. 

 Long. -27, lat. '5, alt. -32 poll. 



Hab. Sta. Barbara (Jewett) • S. Pedro (Cooper). 



74. Subgenus Amiantis*. 



Callista : dente postico utraque valva ruguloso. 



Type : Amiantis callosa, = Cytherea callosa, Com*., = Dosinia 

 callosa, Brit. Assoc. Rep. 1857 (from fragments) : non Venus cal- 

 losa (as of Conr.), Sow., Rve., Desh. 



Hab. Sta. Barbara (Nuttall, Jewett) ; S. Pedro (Cooper) • Cape 

 St. Lucas (Xantus). 



This section differs from the typical Callistce as does Merce- 

 naria from Venus. Whether the other peculiarities of the spe- 

 cies (redescribed by Reeve as Cytherea nobilis) are coordinate, 

 cannot yet be stated, as it stands alone. In sculpture and colour 

 it resembles Dosinia ; in its ponderous growth, Pachydesma. 



110. Lazaria subquadrata. 



L. testa extus Cardites variegatce jun. simili ; pallida, castaneo tincta; 

 subquadrata, antice truncata, subregulariter ventricosa, dorsaliter 

 tumida ; costis radiantibus circ. xiv.-xvi., tumidis, nodosis, dia- 

 gonalibus majoribus ; interstitiis plus minusve insculptis : intus, 

 valva dextra dente cardinali triangulari, inter duas fossas sito, haud 

 elongato ; dent. lat. a cardine separatis, ant. extante, post, obsoleto, 

 calloso : v. sinistrali dent. card. ii. angustis, subsequalibus, radi- 

 antibus ; lat. ant. et post, extantibus : cicatr. adduct. subrotun- 

 datis. Long. '37, lat. *25, alt. *34. 



Hab. Sta. Barbara (Jewett) ; Monterey, and along the coast to 

 S. Pedro (State Coll. no. 403) (Cooper). 



The outside of this remarkable little species is typically Car- 

 ditoid; the hinge is intermediate between Lazaria and Cypri- 

 cardia. 



132. Modiola fornicata. 



M. testa curta, lsevi, latiore, maxime fornicata; pallide carnea, epi- 

 dermide rufo-fusca, rugis incrementi et incrustatione densissime 

 pilosa induta ; umbonibus maximis, spiralibus, antice torsis, per 

 tres quadrantes totse latitudinis devectis ; area ligamentali curtis- 

 sima, arcuata; margine dorsali antice nullo, postice longo, arcuato; 

 margine ventrali recto, vix propter byssum hiante ; postico lato, 

 antico angusto ; altitudine dorsaliter valde elevata, ventraliter 

 plane declivi, cuneiformi ; umbonibus trans marginem anticum per 

 sextantem totius longitudinis excurrentibus : intus, sub umbonibus 

 excavata ; cicatr. adduct. ant. ventraliter sita. Long. T4, lat. '76, 

 alt. -95. 



Hab. Sta. Barbara (Jewett) ; Monterey (Taylor). 



* Th. afilavTos, 6 ko\ f/, unpolluted. 



