MARTNE BIOLOGICAL STATION AT PORT ERIN. 55 



12.000) that could be obtained from various expeditions, 

 and published in the " Challenger " series a most authoritative 

 report, which will be for long the standard work on the subject. 

 Omitting terrigenous deposits, which are formed close to 

 the shore and are made up chiefly of matters washed down 

 from the land or worn off from the coast, the deep-sea " oozes," 

 as they have come to be called, are divided into various kinds, 

 such as Globigerina ooze, Radiolarian ooze, Diatom ooze, 

 Pteropod ooze, according to the nature of their chief con- 

 stituents, while another most extensive deposit, occupying 

 over 50 million square miles on the floor of the ocean at depths 

 of over 2,000 fathoms, contains comparatively few conspicu- 

 ous organisms and is known as Red Clay because of the 

 alumina and iron and manganese which it contains. In some 

 places associated with the Red Clay are found great deposits 

 of manganese nodules, ear-bones of whales, and gigantic 

 sharks' teeth apparently belonging to extinct species. It was the 

 "Challenger" observations that first enabled oceanographers 

 to map out the distribution of these pelagic oozes on the 

 floor of the ocean, and which first gave us a rational explanation 

 of their nature and process of formation. 



In connection with deep-sea deposits, it may be appro- 

 priate to point out that it was the naturalists on the 

 f Challenger " who pricked the bubble of " Bathybius " 

 and made known the real nature of that mythical organism. 

 Some eminent biologists of the past, from an examination 

 of some of the earlier deep-sea dredgings, had come to the 

 conclusion that a grey gelatinous material, sometimes found 

 in such deposits, was the remains of a primitive protoplasmic 

 living slime covering the ocean bottom as a nutrient pabulum 

 upon which, in the absence of plants, the more highly organised 

 animals could graze — reminding one of the good old days in 

 Ireland when — 



*'*' The streets of Kilkenny were paved with penny loaves, 

 And the houses were thatched with pancakes." 



