1865.] DUNCAN ASIATIC ECHINODERMATA. 357 



those types which, foreshadowing the fauna that attained its maxi- 

 mum of development in early Tertiary times, complicate the palaeon- 

 tology both of the South-Indian and North- American Chalk. 



The nearest Cretaceous strata to the south of Bagh are those which 

 were noticed by Messrs. Kaye and Cunliffe, and whose fossils were 

 described by Edward Forbes and Sir Philip Egerton*. The collec- 

 tion from Pondicherry has no species in common with those at Bagh 

 and South-eastern Arabia, and its fossUs, according to Forbes, belong 

 to a lower horizon ; but the Trichinopoly beds yielded fossils which 

 have a slight community of facies with the northern ; there are, 

 however, no identical species. If those species which Edward Forbes 

 considered to be unusual in the Cretaceous fauna be removed from 

 the collections from Trichinopoly and Verdachellum, this community 

 of facies becomes stronger, and it is evident that it is produced by 

 the forms which are common to the European and South-Indian Cre- 

 taceous faunae. 



The vaiieties of Hemiaster similis at Eas Sharwen and Bagh are 

 remotely allied to Forbes's Brissus ranaf; and Hemiaster Cenoma- 

 nensis from Bagh is allied to Brissus expansus, Forbes, both the 

 Brissi being really Hemiasters. 



Here the similarity ends ; and the northern beds, being on an 

 horizon inferior to those at Trichinopoli and VerdacheUum, are pro- 

 bably the equivalents of the Ootatoor beds^. 



The other Cretaceous rocks of India, as yet described§, belong to 

 the Upper Chalk, and their organic remains point clearly to a higher 

 horizon than those of Bagh and S. E. Arabia. The great Cretaceous 

 deposits of Sinai, Egypt, Syria, Palestine, Asia Minor, and the Cau- 

 casus, whose fossils are comparatively unknown, do not ally the 

 strata under consideration with the Crimean, Russian, and Eastern 

 European Chalk, except in a general sense. The few Echinodermata 

 from Sinai and Egypt |] have no affinity with those just described; 

 but the ubiquitous Pecten quadricostatus is common in the Chalk in 

 Northern Asia Minor at the Kara-dagh^. Von Buch and Abich** 

 determined a Neocomian and an Upper Greensand, with a doubtful 

 Gault, in the Caucasus : although there are many species common to 



* Trans. G-eol. Soc. 2nd ser. vol. vii. p. 97. 



•f- The student of some of the great French works on the Eclunodermata may 

 perhaps be astonished at my referring this fossil to Edward Forbes. It is referred 

 to Desor by D'Orbigny without any notice being taken of the original describer. 

 The manner in which these little mistakes (which, however, are never made to 

 the detriment of Pi'ench observers) are brought about is instructive. Forbes 

 described the species as Brissus rana ; long afterwards Desor (Catal. Rais. p. 125) 

 altered the generic name to Hemiaster, and subsequently D'Orbigny, dropping 

 Forbes's name, calls the fossil Hemiaster rana, Desor. The same thing occurred 

 with regard to Forbes's Brissus expansus and B. incequalis. In fact, the reader of 

 D'Orbigny's ' Pal6ontologie Fran^aise' naturally I'efers all these species to M. 

 Desor, who honourably gives the synonyms in his ' Synopsis des Echinides,' 1858. 



\ For information about these beds, see H. F. Blanford, Memoirs of the Geol. 

 Survey of India, vol. iv. ; also infra, p. 407. 



§ Oldham, Quart. Journ. Geol. Soc. vol. xix. p. 526. 



II Desor. Synopsis des Echinides Fossiles. 



•II Bull, do la Soc. G6ol. de Fr. 2nd ser. vol. xvi. p. 398, 1850 (Tchihatcheff). 



** Zeitschrift der deutsch. geol. Gesell. vol. iii. p. 15, 1850-51. 



