Mr. E. H. L. Schwarz on Coccoliths. 341 



XLTI. — Coccoliths. By Eenest H. L. Schwakz, A.R.C.S. 

 (From the Geological Research Laboratory, Royal College 

 of Science.) 



Coccoliths were first discovered by Ehrenberg * in chalk, 

 and described as inorganic bodies like those constituting 

 " agaric-mineral " (calcium carbonate precipitated from solu- 

 tion in natural mineral water) or kaolin ; according to him 

 they were flat bodies having concentric rings on their surface, 

 and later he gave them the name of " chalk morpholiths " f« 

 Huxley + and Wallich § declared these bodies occurring in 

 the chalk to be the same as those existing in the sea at the 

 present day ; the former called them, " for convenience," 

 coccoliths — a term which has supplanted Ehrenberg's 

 morpholith. Huxley || distinguished two forms, one simple, 

 the other double, and called them respectively discoliths and 

 cyatholiths, which Hajckel ^ later rechristened monodiscs 

 and amphidiscs. In both the latter papers they were described 

 as being formed as crystalloids in a giant Amoeba — Bathy- 

 bius — which had all the appearance of protoplasm, fibrillar 

 network, &c, but which Murray and Buchanan ** proved to 

 be gelatinous calcium sulphate precipitated by the alcohol in 

 which the soundings were preserved. Up to this point they 

 were not considered to be organisms themselves ; but Sorby j"f 

 put forward this idea, which was stoutly contested by 

 Barrois JJ, who, with many others, e. g. Harting §§, considered 

 them to be mineral concretions. Giimbel |||| and Carter ^ffl 

 considered them to be connected with the reproduction of 

 calcareous algae — Melobesia &c. — and the former described 



* Monatsber. Berlin Acad. 1836; Poggendorffs 'Annalen,' 1836, 

 vol. xxxix. pi. i. fig. 2 B. 



t ' Microgeologie,' Leipzig, 1854, pi. xxv. fig. B, 16. 



X Appendix to Capt. Dayman's Report of Soundings taken in Il.M.S. 

 1 Cyclops,' 1858. 



§ Ann. & Mag. Nat. Hist. 1868, ii. p. 317. 



|| Quart. Journ. Micr. Sci. viii. 1868. 



*[ Biol. Studien, Beitrage zur Plastidentheorie, p. 85 (1870). 



** Proc. Roy. Soc. Lond. vol. xxxiv. p. 605. 



ft Ann. & Mag. Nat. Hist. 1861, viii." p. 193. 



XX Ann. des Sci. Nat., Zoologie, 6 se"r. t. iii. p. 70 (1876) ; ' Recherches 

 sur les terrains anciens des Asturies,' Lille, 1882. 



§§ ' Recherches de Morphologie synth^tique,' Haarlem, 1872. 



Illl " Ueber Cocc. et Nullipores,'' Wien. Verbandl. Geol. 1870, p. 201 • 

 also Neues Jahrbuch, 1870, p. 752, 1873, p. 299. 



^% I quote this on the authority of Barrois, having looked through most 

 pf Carter's papers in vain. [Mr. Carter's paper here referred to appeared in 

 Ann. & Mag. Nat. Hist. ser. 4, vol. vii. 1871, pp. 184-189, " On Melobesia 

 unicellularis, &c." — Eds.] 



