226 DR. CARPENTER'S RESEARCHES ON THE FORAM1NIFERA. 



but probably a Lunulite. Of the species subsequently described by other authors, I 

 entertain no doubt that the O. disculus of M. LEYMERIE *, as well as in all proba- 

 bility the O. plana of M. D'ARCHIAC, is nothing else than a variety of O. complanata, 

 more especially as its young is said to be like the O. macropora of Maastricht. The 

 O.gensacica, O. set-u/ts, and O. socialis of M. LEyMERiE, are all undoubtedly Orbitoi- 

 des, and all belong, I believe, to the same species ; though on this point I could not 

 speak positively, without an examination of their internal structure. So, again, the O. 

 mamillata, O. Fortisii (O. gigantea of D'ORBIGNY), O. papyracea, O. stellata, O. sella 

 and O. radians (O. radiata of D'ORBIGNY) of M. D'ARCHIAC -f- are all probably Orbi- 

 toides, as he has himself subsequently recognized in regard at least to some of them J. 

 The O. elliptica of MICHELIN, so far as I can judge from the figure he gives of it 

 (pi. /I, fig. 1 1), is certainly not entitled to rank as a distinct species, its elliptic form 

 being utterly insufficient to separate it (^j 47.). And as I have already pointed out 

 (^| 49.), unless some distinctive character be furnished by the internal conformation 

 of the bodies which have been ranked in the genus Cyclolina by M. D'ORBIGNY, this 

 also should take rank merely as a variety of Orbitolites . 



VII. Concluding Remarks. 



71. It might be asked with some show of reason, what good purpose can possibly 

 be answered by such a minute and prolix description of a type of animal structure, 

 so mean and insignificant as that which has been occupying our attention. To such 

 a question I would reply First, that I hold it to be a worthy labour to learn, and to 

 place within reach of others, everything that can be learned respecting any form of 

 Organized Being ; that such a complete acquaintance is the great desideratum in 

 every department of Biological Science ; and that no works have ever exercised so 

 beneficial an influence on its progress, as those admirable Monographs of single 

 species, which, by thoroughly elucidating their structure and physiological history, 

 have served as a basis for all subsequent inquiry into the nature of the Plants or 

 Animals formed on a like plan: Secondly, that such an inquiry can scarcely be 

 otherwise than of peculiar utility, as relating to a tribe of Animals whose nature and 

 history are almost as unknown to us now, as those of Polypes were to the Naturalists 

 of a century ago, when TREMBLEY wrote his immortal ' Me" moires pour servir a 

 1'Histoire d'un Genre de Polypes d'eau douce;' what little is known respecting them, 

 being of a nature to mark them as distinct from every other type of living beings 



* Mem. Ge'ol. Soc. de France, 2 se'r., torn. v. pp. 190, 191. 



t Ibid. torn. ii. p. 178, and 2 ser., torn. iii. p. 4. 



J Description des Animaux Fossiles du groupe Nummulitique de 1'Inde, p. 350. 



For a recent description of a form of this reputed genus, which occurs in contiguity with typical Orbito- 

 lites, and which seems to me to correspond in every respect with those recent specimens of which Plate VII. 

 fig. 14 exhibits the external aspect, see Mr. CARTER'S Memoir on the Fossil Foraminifera of Scinde, in 'Ann. 

 of Nat. Hist.,' 2nd ser., vol. xi. p. 174. 



