MR. S. HANLET ON THE LINNEAN MS. OF THE ' MUSEUM ULRICA.' 55 



C. OBLONGA. Sp. oblongus, antice angulatus, dentibus anticis acutis. 



" Unico " (error for " unicus ") originally preceded " in altera valvula." 



C. coRDiFORMis. Buc. subrotundum laeve, umbonibus recurvatis. 



The brief description in the ' Systema ' had evidently been copied in the 

 manuscript by our author himself, who cited Gualt. t. 71. f. E. as the sole 

 synonym. The specimen had apparently been added to the collection, 

 subsequently to the drawing up of the first catalogue. 



ARCA. 



Testa crassa, umbonibus distantibus intus fornicatis. Cardo planus, 

 masticatus dentibus numerosis minimis sequalibus transversis. 



A. TORTUOSA. A. oblonga obliqua, valvula altera oblique carinata. 



" Nates, &c." and " Cardo, &c.*' were the printed additions to the earlier 

 description. The * Systema' synonyms of Klein (t. 8. f. 16) and Bonanni 

 (2. f. 128) were present in the manuscript. 



A. No^. A. oblonga angulata hians. 



This manuscript furnishes us with the additional synonyms of 



" Aldrov. 3. p. 613." and " Sloan. Hist. 2. p. 257. Musculus Matthioli," 

 besides the previously published references to Lister (368. n. 208) and 

 Bonanni (2. t. 32). The formation of the hinge was not, however, indicated, 

 and the passage commencing with " Nates " has been enlarged from " Um- 

 bones remotissimae, area interjecta concava, ad angulura rectum striata. 

 Margo exterior in medio hians, apertura barbata.'* 



The intended specific epithet was A. Noemi. 



A. ANTiauATA. A. testa oblique cordata, transversim sulcata, antice 

 angulo compresso, rima intra rhombum transversim striata. 



The admixture of two species (at the least) in the published edition 

 resulted from the amalgamation of two earlier descriptions. To the above 

 diagnosis belonged the printed details with the following important changes. 

 In place of " extus striata longitudinaliter sulcis crenatis," the reading was 

 simply " intus striata longitudinaliter,'* and in lieu of " interjecto spatio 

 rhombeo piano," merely " rima patens." 



The proposed name for this shell, from a supposition of its identity with 

 the Pecten virgineus of Rumphius, was A. virginea. The other species 

 which Linnaeus referred to the same numerals of the ' Systema ' was not 

 named, but was thus characterized : — 



A. (Sys. n. 144). A. cordata, sulcis nodosis, rima decussatim striata. 



List. Hist Pecten polyleptoginglymus, &c. 



Gualt. t. 87. f. C. 



Testa reliquis magis gibba, albido-flavescens, sulcis xxx obtusis, trans- 

 versim nodosis : nodis transversis, obtusissimis, imbricatis. Intus albida. 

 Margo dentibus xxx argutiusculis. Rima sulco rhombeo circumscripta, 

 disco decussatim vix manifeste striato. Umbones distantes ad neutrum 

 latus flexi. 



A. SENILIS. A. oblique cordata, octosulcata, laevis, antice hians. rima 

 obtusangule striata. 



