364 Mr. J. Y. Buchanan [May 29, 



this is the true explanation we ought to be able to find traces of free 

 sulphur in the mud, although the finely divided sulphur which is pro- 

 duced in this class of reaction is easily oxidised. Acting on this 

 idea, and connecting it with Oscar Peschel's brilliant application of 

 the JRelicten fauna of lakes and rivers in the diagnosis of morpho- 

 logical terrestrial changes, I treated a series of oceanic muds and 

 manganese nodules with chloroform for the extraction and deter- 

 mination of any sulphur that they might contain. The experiment 

 was successful in every case, and the results are given in a paper * 

 on the occurrence of sulphur in marine muds, read before the Royal 

 Society of Edinburgh. When surveying the Gulf of Guinea in 1886 

 in the Buccaneer, I found this coprolitic character of the mud near 

 the mouth of the Congo so highly developed that in the reports of the 

 soundings I had to introduce a new designation for this class of mud, 

 namely coprolitic mud. Returning, however, to the first cruise of the 

 voyage, namely that from Tenerife to Sombrero, it was firmly 

 established that the nature of the deposits in the open ocean varies 

 in a definite way according to the depth of the water. Between 

 1000 and 1500 fathoms we have the pteropod shell. At greater 

 depths they disappear and the calcareous portion of the mud consists 

 of shells of foraminifera to a depth of about 2500 fathoms. Be- 

 yond this depth the foraminifera rapidly disappeared, and at a 

 depth of over 8000 fathoms the mud consisted almost entirely of 

 red ochreous and argillaceous matter. During the second year of 

 the voyage the diatomaceous ooze of the Antarctic ocean was dis- 

 covered, and later still in the Pacific the radiolarian ooze. Starting 

 therefore with the expectation of finding a more or less universal 

 chalk formation at the bottom of the ocean, the result of the 

 Challenger's work in the first two years was to open up a new geo- 

 logical world and to show its dependence on the physical condition 

 of the oceans. 



Bathybius. — When the Challenger started on her voyage, it was 

 not only expected that the bottom of the sea would be found 

 everywhere covered by a calcareous deposit, but it was believed that 

 it had been shown that the mud at the bottom of the ocean was 

 everywhere associated with an all-pervading organism to which 

 Huxley ,t its discoverer, had given the name of Bathyhius. 



The following extract from Wyville Thomson's ' Depths of the 

 Sea,' p. 410, gives a description of a mud in which this mysterious 

 being was believed to be present. 



" In this dredging, as in most others in the bed of the Atlantic, 

 there was evidence of a considerable quantity of soft gelatinous 

 organic matter, enough to give a slight viscosity to the mud of the 



* 'Oil the Occurrence of Sulphur in Marino Muds and Nodules, and its 

 bearing on their Mode of Foriiiatioii.' By J. Y. Buchanan, F.K.S., Proceedings 

 of Koyal Society, Edinburgh (1890), vol. xviii., pp. 17-39. 



t Journal of Microscopical Science (1868), vol. viii., p. 1. 



