FINDING OF THE BACILI.ARIAN BF:dS ON THE 

 OCEAN BOTTOM. 



BY ARTHUR M. RDWARDS, M. D. 



The finding of Bacillarian beds, in fact the layers of 

 diatoms, on the ocean bottom, is not new, although the 

 importance of it is just now shown. For as the Bacillaria 

 make up the clayey stones of vast regions in the world, they 

 are also seen in the rock that is forming now, called " recent " 

 by geologists, in the bottom of the sea. 



They have been observed since 1818. In fact Bacillaria, 

 or diatoms themt^elves, were not known much before then. 

 And the discovery that they are synonymous with the great 

 deposits of the world, those namely of Denmark, Spain, 

 Greece, Africa, North America, South America, Japan and 

 New Zealand, is likewise not new. In Denmark they are 

 placed, tentatively, in the Late Tertiary, near the Recent 

 strata containing living forms ; in Spain in the Miocene, or 

 still lower in the Oligocene Tertiary ; in Greece, by Ehrenberg, 

 who discovered them, below, in the Cretaceous; in Africa, 

 also by Ehrenberg, in the Tertiary ; in North America, by 

 Rogers, in the Tertiary ; in California, by Blake, who follows 

 Ehrenberg in this, in the Tertiary. But here they are first 

 studied thoroughly, and I put them in the Recent, because 

 holding Recent forms identical with those brought home by 

 the "Challenger" and "Tuscarora." In South America, 

 in the North, in Peru, where geology has not been studied, 

 they have not been placed at all. But from the South, in 

 Patagonia, they were sent by Darwin to Ehrenberg, and 

 placed by doubtful evidence in the Tertiary. Hatcher brought 

 back some rock which he thought was Tertiary. I have 

 examined this and I find Bacillaria in it. From Japan Pom- 

 pelley brought back some rock which he submitted to me, and 

 placed it doubtfully in the Tertiary. I reported on it at the 

 time in the "Smithsonian Transactions" and found it was the 

 same as the Virginian and Californian rock, in the way of 



