Zoological Sociehj. 511 



but not so angular, and having the ribs richly ornamented by vaulted 

 imbrications in the centre, and very minute crenulations raised into 

 points at the sides. Unfortunately, we possess no information re- 

 specting the locality. 



Cardium imrricatum. Conch, Illustr. f, 48. Card, testa crassd, 

 ventricosn, antice rotundatd, jwsticc suhquadratd, angulatd; 

 albd, intus aurantiacd, purpurea tnaculatd : co.stis 28, quarum 19 

 anterior'ibus valde imbricatis,postrenns suhlcevibus, subangulatis, 

 imbr'tcatis propc umbones, angulat'is, fornicatis, inope marginem 

 ventralem obtusis. 



Long. 1-20; lat. 1-05; alt. 1-30 poll. 



Hab. ad oras AustralicE (Swan River). 



Like C. medium in general form, but having vaulted imbrications 

 on the ribs. These are much thicker and larger than in C fornica- 

 turn, and the sides of the ribs are not crenulated as in that species. 



Cardium subretusum. Conch. Illustr. f. 24. Card, testa albd, ob- 

 lique subquadratd, ventricosd, postice subcarinatd, acuminatd ; 

 antice subrotundatd ; post angiilum complanatd, leviier sulcatd; 

 costis ante angulum sex, tuberculatis ; interstitiis 2}unctatis ; 

 ante umbones cavernuld cordlformi, intus leviter callosd. 

 Long. 0-90; lat. 1'20; alt. 1 30 poll. 

 Hab. 



Thus we have three species presenting the character in common, 

 of having a callosity within a heart-shaped cavity, close under the 

 umbones, namely, the true C. retusum ; the var. " (2.) testa punctis 

 sanguineis picta" of Lam., which has been named C. auricula by 

 Forskiill, and the present species, which resembles the original C re- 

 tusum in general appearance, but it is more elongated and smoother 

 behind the angle, the cavity is not so deep, and the callosity is more 

 strongly marked. 



Cardium fragile, Conch. Illustr. f. 68. Card, testa rotrtndatd, 

 tenui, Icevi, subequilaterd, postice jyauld injlatd, albd,fusco-lineatd, 

 epidermide fulvd indutd ; i7itus albd ad marginem rtibescente ; 

 ad umbones Jlav a ; margine leviter sulcato. 



Long. 1-05; lat. 0-65; alt. 1' poll. 



The only specimen at present known is in the collection of the 

 Rev. F. J. Stainforth. We have no information as to its locality. 



Cardium foveolatum, Conch. Illustr. f. 65. Card, testa subro- 

 tundato-ovali, compressd, albd, costis 43, quarum 25 anterioribus 

 rotundatis, crenulatis, deinde p)osterioribus 10 Icevibus, subangu- 

 latis, extremis concavis, ad latera crenulatis. 

 Long. 1-45; lat. 0-90; alt. 1-55 poll. 

 Hab. ad oras Australiae (Swan River). 



The last ribs on the posterior side are hollow, with crenulations 

 crossing them so as to form little pits. This species belongs to the 

 same section as C. muricatum, but it is much flatter and has a greater 

 number of ribs. 



