OF SOiJTHEEN INDIA. 215 



116-142.— Meek mentions the following in his Check-list of invert, cretaceous fossils of North 

 America^ (Smiths. Misc. Coll.,, No. 177, 1864^, p. 12)^ — C. ahruptunij Coloraclense, congestum, curtuin, 

 Mtfalense, hemicydum^ mediale, muUiradlatum, Ripleyense, speciosum, Tlppanum, ArJcansense, Brazoense, 

 Choctawense, filosum, mtdtutriatum, pertenue, rarmn^ scUiduniy suh-quadratiim, Texanum, Spillmani ; 

 the last eleven species belong* to Protocardium, the others to the sub-genus Acanthocardmm. Besides 

 these are noticed Pappidea elegantula, hella, (not Card, helium, Con.) ^protexta, rostrata, and sancti- 

 aahce ; the first four being" referred to the sub-g-enus LiopistJia, but I have already (p. 208) observed 

 that it appears doubtful whether these forms are correctly placed in the Cardiidje ; some other 

 externally closely allied species undoubtedly belong to Pholadomya, and the same may be the case 

 with these few species. 



143-149. — C, Pemondiamim, Cooperii, Brewerii ; C, (Lcevicardium) linteum, annulatum, C. (Pro- 

 tocardium) Placer ense and transluciduwi are recorded by Grabb from the cretaceous rocks of California 

 (Pal^ont. Calif., ii, p. 242). 



150-152. — C. suhtentum, Protocardium gamhrinum, and Virginianum are from the so-called 

 lower eocene beds (see Conrad^s Check-list, &c., Smiths. Misc. Coll., No. 200, 1866, p. 6). 



153-154. — C. Columhiamim, and acuticostatitm, d^Orb., (Pal. Am. Merid., pp. 82 and 120) ; the 

 last was first described from beds on Quirquina, said to be tertiary ; it has rather a recent aspect and 

 appears to belong to Cardium proper, but subsequently d''Orbigny (Prod, ii, p. 242,) referred the 

 species to Sen on ien 



155. — C. australinum, d^Orb., Prod, ii, p. 242, is also from Chili. 



156-157. — C. pedernale and transversale from Texas are stated by Romer to be rather in- 

 sufficiently characterised from existing materials (Kreideb. von Texas und ihre org. Einschliisse, 

 Bonn, 1852, pp. 49 and 50) ; the former is a Protocardium, 



158-159. — C. sahdosum and C. (Prot,) granuliferum are described from Mexico by Gabb, (Pal. 

 of Calif., ii, p. 267). For the first a new sub-genus, Granocardium, has been proposed, which 

 appears quite unnecessary, as already mentioned (p. 207). 



160-161. — The Indian species are as follows: — C. incomptum, exidans, productum. belong to 

 T r achy car dium ; C. (Acantliocardium) pullatum ; C, (Cerastoderma) pilatum; C. ( ? Pectunculus) 

 scrohicidatumy Protocardium hillanum, delicatulum, Pondicheriense, altum and hiseotum ; Fragum 

 prrdcurrens. Of this only G. productiirn and Protoc. liillanum are identical with European species. 



Looking at this large list of species of cardiin^ from cretaceous rocks, we find that the 

 sub-generic forms Acanthocardium, PectnnculuSy and Tr achy car dium are the most common ; next 

 comes the peculiar more ancient type Protocardium, and then its close ally Lcevicardium ; of Cerasto- 

 derma there are no more than one-twentieth of the whole number ; of Serripes and Fragum only 

 one or two of each, while Cardium as restricted, Lunulicardium and Hemicardium are not at all 

 represented. As to geographical distribution the list shows that the above noted sub-genera are 

 found wherever cretaceous rocks have been met with, and thus the geographical distribution was 

 then much the same as it is now, of course with the exception of the present arctic regions. 



