CAEDIUM.— Plate VII. 



The half Cockle. Shell cordate, swollen, obliquely 

 quadrilateral, posteriorly compressed, radiately ribbed, 

 ribs about six and twenty in number, flatly convex, 

 interstices peculiarly closely punctured, posterior ribs 

 smooth, anterior ribs tubereularly crenated, divided 

 from the posterior by a prominent keel running down 

 from the umbone to the margin in each valve ; white, 

 posterior area sometimes stained with small pink 

 spots. 



Linn;eus, Syst. Nat. (Gmelin edit.), p. 3216. 

 Hemicardium ? Cuvier. 



Hai. St. Nicolas, Island of Zebu, Philippines (found in 

 sandy mud at low water) ; Cuming. 

 The little tubercles which adorn the anterior ribs of this 



species are always worn away towards the umbones. 



Species 39. (Mus. Cuming.) 

 Cardium auricula. Card, testa subquadrato-cordatd, 

 raid:- tumidd, postice concavo-depressd, radiatim indi- 

 stinote costatd, costis phuudatis, inier&titiis enliter 



hrribux, anticix hie il/ic tuber- 



""■.'!'- 



punctahs, costis 



culato-crenatis, carina svbobtmd ah umbone ad 



nem decurrente divisis, lunula profundi excavatd, cat- 



loso intrudo ; lutescente-alid, maculis rosacek partis 



ehganter tinetd. 



The ear Cockle. Shell somewhat squarely cordate, very 

 much swollen, posteriorly concavely depressed, indi- 

 stinctly radiately ribbed, ribs flattened, interstices 

 faintly punctured, posterior ribs smooth, anterior ribs 

 here and there tubereularly crenated, separated from 

 the posterior by a rather obtuse keel running down 

 from the umbone to the margin; lunule deeply ex- 

 cavated, with a callosity intruding; yellowish white, 

 elegantly stained with pink spots. 



Forskael, Fauna Arabica, f. 122. 



Hull. Suez, north-west extremity of the Bed Sea ; Buppell. 



There appears to be about the same number of ribs in 

 this as in the preceding species, but being rather indi- 

 stinctly developed they cannot be enumerated with accu- 

 racy. The lunule is hollowed out with remarkable force. 



