Sea-bottom procured hy H.M.S. ^ Challenger.^ 291 



It may be taken as proved that there is no want of Foramini- 

 feral life in the ^Imlitorranean. Prof. W. C. Williamson long 

 ago pointed ont that the " white mud " of the Levant is mainly a 

 Eoraminiti'ral deposit; I found a similar mud covering the bottom 

 along the Tripoli coast; Mr. J. (xwyn JelYreys has dredged Fora- 

 minifera in al)undance in the liay of Spezzia, Captain Spratt in 

 the yEgean, Oscar Schmidt in the Adriatic, and I myself at various 

 points in the Western basin along the northern coast of Africa. 

 That Foraminifera, especially Glohi;/erin(n, abounti in its surface- 

 water at Messina, is testified by Hiickel in the passage cited by 

 Prof. Wyville Thomson ; and when it is considered how large an 

 influx of Atlantic water is constantly entering through the Straits 

 of Gibraltar, and is being diffused throughout the MediteiTanean 

 basin, and how fa\ourable is its temperature-condition, it can 

 scarcely be doubted that, if the doctrine now upheld by Prof. 

 Wyville Thomson were correct, the deposit of Glohi'jerinfi-shnWs 

 over the whole bottom-area ought to be as abundant as it is in 

 the Atlantic under corresponding latitudes. Yet I found the 

 deeper bottoms, from 300 fathoms downwards, entirely desti- 

 tute of Globigerine as of higher forms of animal Ufe ; and this 

 was not my own experience only, but was also that of Oscar 

 Schmidt, who made a similar exploration of the Adriatic. In my 

 first visit to the Mediterranean, in the ' Porcupine' (1870), many 

 hundredweight of the fine mud brought up by the dredge from 

 great depths in the Western basin were laboriously sifted, and 

 the sittings carefully examined, without bringing to light more 

 than a stray drift-shell here and there. And in my second ^'isit, 

 in the ' Shearwater' (1871), I examined all the samples of bottom 

 brought up by the sounding-apparatus from great depths in the 

 Eastern basin, with the same result — gi'viug all the more care to 

 this examination, because Capt. Xares (probably through not having 

 kept separate in his mind the results of the deeper and of the 

 shallower soundings which he had previously made in the Medi- 

 terranean) assured me that I slwuld find minute shells imbedded in 

 the mud. 



I can see no other way of accounting for the absence of Glohi- 

 gerina-ooze from the bottom of the Mediterranean, save on its 

 shallow borders, than by attributing it to the unfavourable nature 

 of the influences affecting the bottom-life of this basin — that is to 

 say, the gradual settling-dowai of the fine sedimentary deposit 

 which forms the layer of inorganic mud everywhere spread over 

 its deeper bottom, and the deficiency of oxygen and excess of 

 carbonic acid which I have shown to prevail in its abyssal waters 

 giving them the character of a staguaut pool — these mfluences 

 acting either singly or in combination. 



Another fact of which Prof. Wyville Thomson is fully cogni- 

 zant, and to which he formerly attached considerable importance 

 as indicative of the bottom-life of the Glob i'/eri nee, is unnoticed 

 in his recent communication : I refer to the singular limitation 

 of the Globif/erina-ooze to the '• warm area " of the sea-bed between 



