390 Mayer-Eymar, Diagnoses Ostrearura novarum 



rugata et striata ; costae radiantes numerosae, insequales, 

 pro parte maxima superficiales, interruptae, evanescentes, 

 paucae majores, fornicatae, raro ad lamellas subspinosae; 

 umbo sensim angustatus, plerumque acutus ; cardo majiis- 

 culus, triangularis, rectus vel obliquus, cauali sensim 

 angustato, paulum profunde, areis latis, planis ; cicatri- 

 cula musculi magna, late semilunaris, lateralis ; margines 

 intus Iffives vel ad cardinem pauci scrobiculati ; valva 

 superior minor ; plana vel plano-concava, tenuis, lamellosa, 

 leviter multiradiata. — Long. 90, lat, 60, in alteris, 

 long. 65, lat. 50 mm. 



Langhianum I, a; Carry prope Massiliam (3 — 4) 

 Mus. Tur. 



Ostrea Descartesi, May.-Eym. 



Testa oblonga, recta, subtenuis ; valva inferior sub- 

 pentagonalis, profunda, irregularis, superne leviter dila- 

 tata, subbialata, inferne rotundata, multilamellosa: lamellae 

 irregularissimae, pro parte rugiformis ; costae longitudi- 

 nales irregularissimae, obscurae ; umbo prominens, rectus, 

 triangularis, acutus ; cardo angustus, canali lato, paulum 

 profundo, areis validis, planoconvexis ; cicatricula musculi 

 maxima, late semilunaris, leviter obliqua; margines ex 

 toto la3ves ; (valva superior minor, plano-convexa, lamel- 

 losa, marginibus Isevibus). — Long. 82, lat. 64 mm. 



Helvetianum I: Manthelan prope Turones (1) 

 Mus. Tur. 



Ostrea Fontanesi, May.-Eym. 



Testa parva, elongata, angusta, leviter arcuata, in- 

 ferne subgeniculata, subtenuis ; valva inferior paulum con- 

 vexa, umbone affixa, dorso subplana, irregulariter lamellosa; 

 costae non multae, superne obscurae, inferne latiores, 

 ■ depressae ; umbo obliquus, leviter incurvus ; cardo longius- 



