DEEP SEA VEGETAL DEPOSITS 519 



noteworthy deposits of plants in marine sediments are the deep- 

 sea accumulations of leaves and driftwood of terrestrial origin. 

 In the Caribbean, on the lee side of the West Indian Islands, the 

 Blake dredged "masses of leaves, pieces of bamboo and of sugar 

 cane^ dead land shells, and other land debris" at a depth of over 

 1,000 fathoms, and ten or fifteen miles from land. (Agassiz-i : 2gi.) 

 The Albatross in its dredging expedition on the west coast of Cen- 

 tral America between the Galapagos Islands, the west coast of Mex- 

 ico, and the Gulf of California, found nearly everywhere a muddy 

 bottom or one composed of Globigerina ooze, and generally con- 

 taining terrigenous matter. Scarcely a single haul of the trawl 

 was made which did not bring up a "considerable amount of de- 

 cayed vegetable matter, and frequently logs, branches, twigs, seeds, 

 leaves, fruits," much as found by the Blake on the east coast, but 

 in vastly greater quantities. Even at a depth of over 2,000 fathoms 

 these remains were found. (Agassiz-2 : //, 12.) 



The Challenger also found twigs, woods, and seeds at a depth 

 of 800 fathoms near Ki Island, and also within 20 fathoms off the 

 coast of Amboina Island, both west of New Guinea. South of 

 Mindanao, at a depth of 2,150 fathoms, palm fruits, and fragments 

 of wood and bark were found, while about 50 miles off the coast 

 of Luzon at a depth of 1,050 fathoms were dredged fragments 

 of leaves, stems and wood, the latter overgrown with Serpula. 



The distance from shore to which material is carried by flota- 

 tion is often indicated by the state of preservation of the mate- 

 rial. White says: 'Tf the material is macerated, corroded, rolled, 

 defoliated, skeletonized, incrusted. or bears other signs of having 

 been for some time in the water it is liable to have been trans- 

 ported for some distance. ... If long in sea water the frag- 

 ments are likely to bear the marks of abundant marine organisms, 

 particularly if in tropical sea water. On the other hand, the occur- 

 rence of clean, unbroken, smooth leaves, and particularly of large 

 segments of fern fronds, with their full complement of carbonace- 

 ous residues, is prima facie evidence of minimum exposure to water 

 and of the least subjection to the action of swift currents or waves." 

 (White-60.) 



BIBLIOGRAPHY XI. 



(See also Bibliography X.) 



1. AGASSIZ, ALEXANDER. 1888. Three Cruises of the Blake, Vol. I. 



2. AGASSIZ, A. 1892. General Sketch of the Expedition of the Alba- 



tross^ from February to May, 1891. Harvard College, Museum Com- 

 parative Zoology, Vol. XXIII, pp. 1-89. 



