the Nomenclature of the Foraminifera, 215 



them, with a corrected nomenclature, into correlation with the 

 great mass of species and varieties, fossil and recent, now to be 

 seen in numerous publications at home and abroad, and thus 

 aid in working out the life-history of some, at least, of these 

 remax-kably persistent and widely diffused Protozoa. 



It is difficult to follow Dr. Ehrenberg in his correlation of 

 the several deposits from which he obtained the figured Fora- 

 minifera, because his identifications of Foraminiferal species 

 and marked varieties are often incorrect, both among those of 

 his own gathering and of these with such as had been figured 

 or mentioned by D'Orbigny. And not merely are there diffi- 

 culties as to species^ but his generic groups are often discordant 

 with the names they bear, and sometimes comprise two or more 

 different genera (see Appendix). Nevertheless, taking a broad 

 view of the results of his laborious, if not very discriminating, 

 work among the recent and fossil Foraminifera, Ave may well 

 congratulate him on having shown that several living species 

 are also to be found fossil in Tertiary and Cretaceous deposits, 

 though both his " species " and his geological conclusions are 

 in many instances open to con-ection. Thus, throughout his 

 interesting memoirs on the subject of the persistence of certain 

 protozoan species, he uses the words " Chalk " and " Chalk- 

 marl " for some Tertiary limestones and siliceo-calcareous 

 earthy deposits ; and, with respect to the zoological determi- 

 nations of the Microzoa, we refer to the following observations 

 on his figures and to the conclusions we arrive at concerning 

 them, as showing the great discordance noticeable between 

 his views and those of other rhizopodists. Yet through- 

 out the work there truly appear numerous such persistent 

 forms, belonging to the Cretaceous, Tertiary, and Recent 

 periods, as his experienced eye really detected and in many 

 instances his lists show, but which, for some occult reason, he 

 failed generally to characterize by description and nomencla- 

 ture, though often grouped naturally on his plates. As with 

 his classification of the Foraminifera among his " Bryozoa " 

 (1839)*, so with his ' Mikrogeologie ' (1854), he failed to seize 

 the clue to the right understanding and disentanglement of 

 these many-featured E-hizopods. Ehrenberg's truthful plates, 

 however, in the magnificent work last mentioned, supply the 

 rhizopodist with a storehouse of beautifully prepared speci- 

 mens, mostly seen by transmitted light, from various fossil 

 deposits ; and from these, for by far the most part, good and 

 useful conclusions can be drawn, as from fresh specimens, 

 except that, being viewed only in one manner (transparent), 



* AbLandl. Bed. Akad. fiir 1838 ; Ann. & Mag. Nat. Hist. vol. vii. 

 pp. 302, 303. 



