197 



T. ovata, subcordata, postice longior, ventricosa, tenuis, con- 

 centrice subslriata, purpureo-fusca, intus nitida; umbones in 

 ^ ant. sili; lamina cardrnalis angusta, sub umbone prominens, 

 sinuosa; cardo v. d. fossa Junulari parum profunda, d. lunulari 

 sublrigono, valido, fossa cardinali angusta, profunda, sublrigona, 

 d. cardinali fere sub medio umbone silo, lunulari paullum mi- 

 nore, rotundato; v. sin. d. lunulari minuto, antrorsum obliquo, 

 fossa lunulari magna, trigona , d. cardinali valido, fossa card, 

 magna, sat profunda; denies lalerales parum prominuli, longi- 

 tudinales; impressio muscularis antica duplex, superior minuta, 

 inferior ovalis, verticalis, posterior ovalis, superne emarginata; 

 impressio palliaris vix discernenda integra videtur. A Mon- 

 tacuta (Lesaea) plane diversa Cyamio antarctico appropinquare 

 videtur habitu, cardinis denlibus, facie testa? interna vesiculosa, 



at ligamentum internum detegere non potui. Boh. Finm. 





Montacuta TURT. 



Cardo: in utraque valva processus poslicus, cristam formans, ab 

 opposite alterius valvae sensim discedenlem, cui inseritur ligamentum 

 triangulare, postice latissimum, anlice sensim angustatum, demum 

 in foramine umbonum minuto exiens; lamina cardinalis ante foramen 

 in dentem unicum efformata. 



307. M. tenella n. T. exacte elliptica, alba, pellucida, antice 

 longior et aliquantum altior, umbonibus in ^ sitis, tenuissima, 

 fragilis, convexa, dente antico v. d. minuto, rotundalo, promi- 

 nulo, v. s. obsolete, crista ligamentali parum elevata, sublongi- 

 tudinali; ^f, |^|. Specimina anglicana M. ferruginosae MONT. 

 differunt forma magis elongata, postice nonnihil angustiore, mar- 

 gine dorsali et ventrali subrectis, dentibus validioribus, crista 

 ligamenti subverticali, elevatiore. M. oblonga TURT. diversa vi- 

 detur "dentibus omnibus erectis", Tellimya glabra BROWN car- 

 dinis structura. Sed cavendum ne ligamentum exsiccaturn pro 

 dente describatur. Boh. 



308. M. substriata (Ligula) MONT., (Montacuta) TURT., MACG. 



Boh. Finm. 



Kellta TURT. 



Bornia PHIL. Poronia RECL. 



Cardo: v. s. denies cardinales bini approximati, quorum posticus 

 sub ipso umbone situs; pone eum incipit fovea ligamenti interni an- 

 gusla, obliqua, relrorsum vergens, jam (in sp. infra enumeralis) in 

 fundo umbonis abscondita, jam (in K. rubra TURT., Poronia Adanso- 

 nii RECL.) apophysi suffulta prominente, crislam formanle; dens late- 

 ralis posticus elongatus, remotus; v. d. dens card, unicus magnus, 



Ofuers. af Kongl. Vet-Al;ad Fork. Ar%. 3. ff.-o 6. 3 



