B6G Geological Society: Anniversary Address, 1842. 



by analogies worked out in the South of France. If our adversaries 

 should prove correct, the microscope of Ehrenberg has done more 

 than the eyes of the geologist ; for whilst in the case of Gosau* the 

 number of tertiary-like genera, such as Volutes, Cerithia, Mitra, 

 <S:c., and the absence of all Ammonites and Belemnites constituted 

 our case, the discovery of the Prussian microscopist goes to prove, 

 from specific forms, that the Eocene or dawn of the present fauna 

 had its germ in rocks as old as our chalk ; and thus if we should be 

 led to adopt his views, which however we can only do after some 

 time and with great caution, the otily barrier line which was abruptly 

 placed between two formations as a general phaenomenon, would be 

 shaded off so as imperceptibly to connect the Secondary and Tertiary 

 states of organic life. 



In our OAvn country this department of the science, which is in 

 a state of great advancement through the labours of Owen, Brown, 

 Stokes, and other naturalists, has been cultivated with mvich zeal in 

 one department by Mr. Bowerbank. Having formerly shown that 

 the flints and cherts of the cretaceous system were originally com- 

 posed (at least in great part) of sjionges, he has lately pointed out, 

 that the fossil bodies in question did not differ as he had supposed 

 from the horny sponges of comnicrce, having recently discovered 

 siliceous spicula in the latter. After a detailed and laborious exa- 

 mination of moss-agates and jaspers from Oberstein, Sicily, and 

 Hindostan, he sees in them all the proofs, more or less distinct, of 

 tubular fibres — of what he believes to be gemmules — and the exist- 

 ence of vascular structure, and hence he infers, that sponges have 

 had a still greater share than he originally supposed in the produc- 

 tion of the solid strata. In the Egyptian jaspers Mr. Bowerbank 

 detects between the layers composing a specimen hundreds of 

 foraminifercE, often difficult to distinguish from species known in 

 the calcaire grossier of Paris. Though as geologists and mineralo- 

 gists we may be startled by the announcement of signs of former 

 life in the geodes of Oberstein, because they are certainly, like our 

 trap nodules of Scotland, inclosed in rocks of plutonic origin, I am 

 quite prepared to admit, with Mr, Bowerbank, that in many jaspers, 

 at all events, the microscope should develope former types of life. 



• In regard to Gosau I must in candour state, that M. d'Orbigny has 

 discovered iu the upper greensand, " Craie diloritee," at Uchaux near 

 Vaucluse, thirty-one species of Ammonites associated with some of the 

 same species of Corals and Univalves, which occur at Gosau, and M. Mi- 

 chclin had indeed previously discovered other Gosau forms of corallines 

 supposed to he of the age of the " gault" deposits, and thus no doubt seems 

 to remain that the myriads of tertiary -liha shells, and the absence of Am- 

 monites and Belemnites on which Professor Sedgwick and myself rested 

 our chief conclusions, cannot be assumed as proofs of the age of the Gosau 

 rocks. It still, however, remains to be ascertained, whether this peculiar 

 tlevelopment of the cretaceous system of the Alps (in which one Am- 

 monite only has been discovered and no Belemnite) is not after all a link 

 between what has been called Tertiary and Secondaiy. At all events, the 

 sections on the flanks of the Alps at Kressenberg, &c. lead to this con- 

 clusion. 



