358 PROCEEDINGS OF THE GEOLOGICAL SOCIEIT. [Marcll 8, 



these last strata and those of the basin of the Loire and at "War- 

 minster, still none of them are found in the collections presented by 

 Dr. Carter. The geology of Abyssinia is so little known that the 

 existence of Cretaceous rocks has been both asserted and doubted. 

 An Holectypus very closely allied to the common species at Eas 

 Sharwen is found in the Constantino Cretaceous beds* in North 

 Africa ; and the Chalk in the Balearic Isles has yielded the Salenia 

 jpersonata. The German Planer (doubtless, from its having been 

 so well examined) presents the first indications of a close affinity 

 with the Arabian and Bagh series ; and this affinity becomes nearly 

 complete in the districts of the French Cenomanien, at Le Mans, I'lle 

 d'Aix, and Yilliers sur Mer, &c., which contains no less than thirteen 

 out of the eighteen Asiatic species, either as identical species or as 

 varieties. The Irish Upper Greensand contains Epiaster distindus 

 and the same variety of Ithynclionella dejpressa, Sow., which is found 

 at Bagh ; and the Salenia personata with Pecten cequicostatus are 

 common to the English Upper Greensand and the strata in South- 

 eastern Arabia and at Bagh. 



The North-American Chalk has but a small palseontological affinity 

 with the distant Asiatic series : a portion of it by no means well- 

 defined has a certain similarity of facies, and in Texas there is a 

 community of species. Eoemer's Holectypus planatus is clearly the 

 species previously described as H. Cenomanensis by Gueranger from 

 Condrecieux, and which is also a characteristic form in the South- 

 eastern Arabian Chalk. Pecten quadricostatus is also a Texan species. 

 Here the affinity between the two series ends, as far as America is 

 concerned ; for the Arabian and Bagh series is on a higher horizon 

 than the Neocomian of the Andes and of Trinidad f. It must be con- 

 ceded that the affinity of the Asiatic species with those of the neigh- 

 bouring Cretaceous deposits will most probably appear greater as new 

 forms are collected, and that the remarkable association of so many 

 familiar species will then become less striking, but not the less true. 



8. The Impossibility of establishing a close Synchronism between 

 the Asiatic and other Cretaceous Strata. — It has been noticed that the 

 red strata of Bagh and South-eastern Arabia, whence the fossils col- 

 lected by Capt. Keatinge and Dr. Carter were derived, rest on un- 

 fossiliferous sandstones. The white limestone which rests conform- 

 ably on the Arabian red strata has yielded no satisfactory series of 

 fossils ; and it may be of Nummulitic age, for the only Echinoderm 

 from it is an Echinocyamus allied to Eocene rather than to the Up- 

 per Cretaceous species. 



The red strata thus stand alone as regards stratigraphy ; but their 

 palaeontology clearly determines them to possess the homotaxis of 

 the typical Upper Greensand strata of Western Europe. 



To determine their contemporaneity is impossible, even relatively ; 

 for the vertical range of so many of the species is so great, and the 

 parallelism of the allied European Cretaceous beds is not exact. 



* Desor, op. cit. 



t Duncan and Wall, " On the Geology of Jamaica," Quart. Journ. Geol. Soc. 

 Tol. iii. p. 1. 



