MOLLUSCA. 77 



A species of rather slight structure, distinguished by its remarkably elongated form, 

 the posterior extremity being sharply acuminated. 



2. IsOCARDIA MoLTKIANA. PL XXII. Pig. 3. 



Two specimens of this beautiful red-spotted variety of the true Chama Moltkiana of 

 Chemnitz were collected at Corea, both amply distinguished from the common species, 

 I. vulgaris, by their solid cordate form and bold development of the ribs. 



81. CARDIUM, Linnceus. 



1. Cardiusi Adamsii. PI. XXII. Fig. 2. Card, testa subquadrato-cordata, postice oblique truncata, 

 angulata, subasquilatera, alba, rubro variegata, costis ad sex et triginta, elevatis, squamulis aculeatis confertis 

 regularibus undique dense arniatis. Beeve, MSS. 



Hab. Shores of Borneo. 



Several examples of this most exquisitely sculptured species were collected on the coast 

 of Borneo. 



2. Cardiuit atjrantiactjh. PI. XXII. Fig. 4. Card, testa subcordata, gibba, glabra, nitida, albo 

 aurantiaco ruboque variegata, longitudinaliter striata, latere postico lsevi, antico striis transversis concentricis 

 elevatis subdistantibus exsculpto. 



Hab. China Sea. 

 A fine species, allied to C.pectinatum. 



3. Caedium modestum. PI. XXII. Pig. 6. Card, testa subquadrato-cordata, tenuicula, flaveola, radiis 

 tribus rufescentibus subobsolete picta, radiatim subtilissime et creberrime costellata et coneentrice striata, 

 area, postica subclathrata, margine crenulato. 



Hab. Eastern Seas. 



A thin and minutely-sculptured species, comparatively smooth except on the pos- 

 terior area. 



4. Cardium. Kalamantanum. PL XXII. Pig. 7. Card, testa subcordata, gibbosa, glabra, nitida, 

 lateo-aurantiaca, umbonibus rosaceo-albis, radiatim substriata, latere antico liris obliquis distantibus ex- 

 sculpto, postico lsevi, margine dentato. 



Hab. Shores of Borneo. 



Another species of the C.pectinatum type, apparently distinct from C. aurantiacum. 



5. Cakdhjji speciosusi. PL XXII. Pig. 9. Card, testa subcordata, crassiuscula, tumida, postice 

 peculiariter concavo-truncata, albo rufoque tessellata, radiatim costata, costis ad sex et viginti, convexis, 

 squamato-granulatis, interstitiis transvershn striatis. 



Hab. China Sea. 



Very distinctly characterized from any species known hitherto. 



