Zoological Society. 221 



tning ; Loven, Moll. Scatid. 30 ; Forbes ^ Hanley, Brit. Moll. 334. 

 t. 5Q ; Wood, Index Test. t. 10. f. 10, not Chemn. 



Squama Magna, Chemn. Conch, vii. 87. t. 77. f. 697. 



Anomia Squama, Gmelin, S. N.; Schumacher, Essai. 



Ostreum striatum, Da Costa, Brit. Conch. 162. t. 11. f. 4. 



Anomia undulatim striata, &c., Chemn. Conch, viii. 8. t. 17 . f. 699. 



Anomia undulata, Gmelin, Sj/st. Nat. i. 3346 ; Mont. Test. Brit. 

 1 57. t. 4. f. 6 ; Maton (^ Racket, Trans. Linn. Soc. viii. 103 ; Tnrton, 

 Conch. Diet. 4. Bivalves, 230. t. 18. f. 8, 9 ; Dillio. R. S. i. 289 ; 

 Wood, Index Test. t. 1 1, f. 9. 



Ostrea striata, Pulteney in Hist. Dorset, 36 ; Donovan, B. Shells, 

 ii. t. 45 ; Mont. T. B. 153, 580. 



Anomia striata, Loven, Index Moll. Scand. 29 ; Forbes ^ Hanley, 

 Brit. Moll. 336. t. 55. f. 1, 6. t. 53. f. 6. 



Hab. Coast of Europe. British Seas, Lister. North Sea, Sars, fide 

 Mus. Cuming, n. 51. 



This species is easily known from the other European species by 

 being generally thicker and regularly radiately ribbed, and greenish ; 

 but the number and position of the muscular scars at once separate it 

 from all the multiform varieties of that species. Some authors, over- 

 looking the latter character, have been inclined to regard it as a mere 

 variety. 



I may remark, that the large series of this species which I have 

 examined has shown that the position of the two muscles is liable to 

 a slight variation ; in by far the larger number of specimens the small 

 lower muscle is quite close to and confluent with the scar of the upper 

 larger muscle, but in a few specimens it is separated from the upper 

 larger one by a small interval or space. This has induced me to be- 

 lieve that probably the three West Indian species of the genus may 

 prove, when a larger series of specimens have been collected and com- 

 pared, only varieties of the same species. 



fff Australian. 



9. Placunanomia zealandica. 



Suborbicular, white, smooth ; upper valve with distant radiating 

 grooves ; internally dark green. 



Upper valve with two confluent scars ; upper oblong, longitudinal, 

 lower rather small and more transverse. 



Anomia Zealandica, Gray, in DieffenbacK s New Zealand, ii. 261, 

 1843. 



Hab. New Zealand ; on the inside of mussel shells. 



10. Placunanomia ione. 



Shell white, laminar ; edge of the laminae with small, slender, elon- 

 gated processes ; internally green. 



Lower muscular scars small, round, on the lower hinder edge of 

 the larger one ; sinus or perforations large. 



Hab. Australia, Sydney ; on rocks, Mr. Strange. 



Mus. Cuming; three specimens. ?Van Diemen's Land. 



Dr. Sinclair, Brit. Mus., a single dorsal valve. 



