On the Microscopical Siliceous Polycystina of Barbados. 115 



XIV. — The Microscopical Siliceous Polycystina of Barbados, and 

 their relation to existing Animals, as described in a Lecture 

 by Professor Ehrenberg of Berlin, delivered before the Royal 

 Academy of Sciences on the 11th February 1847. By Sir 

 Robert H. Schomburgk. 



[With two Plates.] 

 Professor Ehrenberg's examination of the different specimens 

 of rock which I transmitted to him from Barbados, proved to 

 him that the geological structure of the district called Scotland 

 in that island owed its origin to submarine organic life, a for- 

 mation which Ehrenberg designated by the term halibiolithic. 

 These forms of minute organic life were so interesting and sur- 

 prising, that Professor Ehrenberg gave a preliminary abstract of 

 the discovery in December 1846 to the Royal Academy of Sci- 

 ences in Berlin, when he described above a hundred species pre- 

 viously quite unknown, and exhibited drawings of eighty species. 

 In the monthly report of the Academy he described 140 new 

 species, divided into twenty-six new and five known genera. 

 Professor Ehrenberg observed at the same time, that the short 

 period which had elapsed since he had commenced the investi- 

 gation of the rocks of Barbados, rendered it improbable that the 

 prolific source of the new organic forms was exhausted. This 

 multiplicity of new forms was unparalleled in the science of natural 

 history ; and he considered it more than probable, that further 

 investigations would make him acquainted with double the num- 

 ber of new forms which he then described. He observed also, 

 that it appeared to him unlikely that the island of Barbados 

 should only contain these peculiar microscopical animals ; and he 

 expected that this would prove to be a new page in the book of 

 science ; but he scarcely could at that time have supposed that 

 in the space of two months he should be able to announce to the 

 Academy that the number of new forms he had examined so far 

 surpassed his expectation, as to lead him to consider this disco- 

 very an intimation that our globe still contains a greater abun- 

 dance of forms than we had previously any idea of. 



Professor Ehrenberg described in 1839, under the name of 

 Polycystina (Zellenthierchen, ' minute cellular animals '), a section 

 of organic forms which belong to the order of Polygastric ani- 

 malcules with siliceous shields, containing the genera Cornutella, 

 Flustrella, Haliomma and Lithocampe*. They had been found 

 hitherto in the chalks and marls of Sicily, in Oran in Africa, 

 and in Greece, and were ascribed to the tertiary period of geolo- 

 gists. At a later period the genus Lit hobo try s was added, 

 which Ehrenberg discovered in the Tripoli of Richmond in Vir- 

 ginia, and in Bermuda. The number of genera and species de- 

 * See Taylor's Scientific Memoirs, Parts X. and XI. 



