— 43 — 



— T. ovata, subcordata, postice lungior, ventricosa, teriuls, con- 

 centrice substriata, purpureo-fusca, intus nitida; umbones ln 

 -} ant. siti; lamina cardinalis anguMa, sub umbuno prominens, 

 sinuosa; cardo v. d. fossa lunuJari parum profunda, d. Iunulari 

 subtrigono, valido, fossa cardinali angusta, profunda, subtrigona, 

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

 nore, rotundato; v. sin. d. Iunulari minuto, antrorsura obliquo, 

 fossa lunulan magna, frigona , d. cardinali valido, fossa card. 

 magna, sat profunda; dentes lalerales parum prominuli, Jongi- 

 ludinales; impressio muscularis antica duplex, superior minuta, 

 inferior ovalis, verticalis, postcrior ovalis, superne emarginata; 

 impi'essio palliaris \ix discernenda integra videlur. — A Mon- 

 tacuta (Lesaea) plane diversa Cyamio antarctico appropinquare 

 videtur habitu, cardinis deniibus, facie testae inferna vesiculosa, 



— af ligamenlum internum detegere non potui. Boh. — Finm. 



Moniacttta Tukt. 



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

 oppusito alterius valvae sensim discedentem, cui inseritur ligamentum 

 triangulare, postice latissimum, aniice 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 



Jongior et aliquantum altior, tunbonibus in £ sitis, ternussima, 

 fragilis, cunvexa, dente anticu v. d. minuto, lOtundafo, promi- 

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

 tudinali; |$, |^|. — Specimina anglicana M. ferruginosa3 Mont. 

 differunt forma magis eJongala, postice nonnihil angustiore, rnar- 

 gine dorsali et ventrali subrectis, dentibus validioribus, crista 

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

 detur "denlibus omnibus erectis'' , Tellimya glabra Brown car- 

 dinis structura. Sed cavendum ne ligamentum exsiccatum pro 

 dente describatur. Boh. 



308. M. substriata (Ligula) Mont., (Montacuta) Turt., Macg. 



Boh. — Finm. 



Kellia Turt. 



Bornia Piiil. Poronia Rhcl. 

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

 sub ipso umbone situs; pone eum incipit foveu Jigamenti interni an- 

 gusta, obliqua, retrorsum vergens, jam (in sp. infra enumeratis) in 

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

 nii Kkcl ) apophysi suffulta promineute, cristam formante; dens late- 

 ralis pOsticus elongatus, remotns; v. d. dens card. unicus magnus, 



