114 SPECIES OF THE SYSTEMA. 
ascribed to that species; its recognition, consequently, was an 
easy task. ‘“ Radii tantum singulari ordine squamis fornicatis ” 
has been written in the revised copy of the ‘ Systema.’ 
Osirvea mallets. 
The Malleus vulgaris (Chemn. Conch. Cab. vol. vii. pl. 70, 
f. 655) remains in the Linnean cabinet, and alone agrees with 
the several descriptions of this species. Naturalists could not 
fail to identify the shell intended by Linneus, since the very 
remarkable shape is confined to two or three known recent 
shells, and of these M. vulgaris alone agrees with the colouring 
indicated in the ‘Museum Ulrice.’ The circuitous mode of 
referring to Lister, is modernised into “t. 219” in the manu- 
script of the younger Linné. 
The following addition to his description was written by our 
author in his interleaved copy of the earlier edition of the 
‘Systema :’ — “Testa rudis, nigra, oblonga, linearis, tunc 
flexuosa, lobi laterales transversi, subulati: cardo hians lacuna, 
cujus medio fossula transyersa cartilag(ine) parva.” 
Ostrea dilubtana, 
The marked type of this species in the Linnean cabinet 
proves to be the shell so denominated by Hisinger, Lamarck 
and D’Orbigny (Pal. Fr. 480). The French obtain it from the 
Lower Chalk formation (Sharpe MS.). The specimen agrees 
with the description. In the revised copy of the ‘Systema’ our 
author has referred us to “ List. t. 486,” a drawing which 
reminds one somewhat of the example, but which not being 
intended for the species (it is referred to O. carinata by Dill- 
wyn) was probably quoted as the nearest approach to it then 
extant. 
