222 Scientific Intelligence. 



Only a small proportion of the material is of organic origin. 

 "The siliceous remains of Diatoms, Kadiolarians and Sponges, 

 together with arenaceous Foraminifera and glauconitic casts ot 

 Foraminifera, make up sometimes 4 or 5 per cent, of the deposit. 

 In 41° 13' 53" N. and 65° 57' 25" W., the depth 810 fathoms (4860 

 feet), there were 5*08 per cent of calcareous material consisting 

 of Coccoliths, Coccospheres, fragments of Echinoderms (these 

 including a few pinnules of Crinoids), and a dozen Foramin- 

 ifera of which the Pelagic kinds included Globigerina bulloides, 

 G. inflata, G. Dutertrei, Puivinulina Menardii, P. Micheliniana 

 and P. Canariensis, and the Bottom-living species were Haplo- 



phragmlum Ca?iariensis, Textidaria ? Bidimina marginata 



Uvigerina pygmcea, Truncatulina lobata, ida and Puivinulina ele- 

 gans. The rest of the bottom material was a mud of mineral char- 

 acter, partly argillaceous, containing Diatoms, Radiolarians, and 

 spicules of sponges. In another dredging in 41° 34' 45" N. and 

 65° 35' 30" W., the depth 1242 fathoms (7452 feet), the calcare- 

 ous portion was 7*25 per cent of the whole. Nearer the coast, 

 in 466 fathoms (2796 feet), 39° 50' 45" N., 70° 11' W., the gray 

 mud was similar to the last and contained 3*46 of calcareous ma- 

 terial. Again at a greater depth, 1394 fathoms (8364 feet), the 

 gray mud was plastic and contained 16*81 per cent of calcareous 

 material ; 40 per cent of mineral grains, that is as above stated of 

 quartz, feldspars, mica, hornblende, magnetite, olivine, glauconite, 

 glassy fragments ; 5 per cent of Diatoms, Radiolarians and Sponge 

 spicules, and 38*19 per cent of argillaceous nature with fragments 

 of siliceous organisms. 



(2.) Beticeen Cape Hatter as and Lat. 31° 48' N. — The materials 

 brought up from depths under 1000 fathoms (with two excep- 

 tions) were green muds or sands, and were situated beneath the 

 Gulf Stream or along its inner margin. The mineral particles in 

 the mud are like those north of Cape Hatteras, but finer (seldom 

 exceeding 0\4mm. in diameter) and evidently have not been 

 transported by ice; they consist of quartz, feldspar, augite, horn- 

 blende, magnetite and a few fragments of glassy rocks. There is 

 frequently an abundance of glauconitic grains and also grains of 

 manganese peroxide. 50 per cent or more of the deposit is 

 usually calcareous, consisting of dead shells of pelagic Foramin- 

 ifera and Mollusks, fragments of Echinoderms, Bryozoa and Coc- 

 coliths. All the tropical species of pelagic Foraminifera occur 

 here while rare north of Hatteras ; 10 or 12 p. c. consist of 

 siliceous organisms, as Diatoms, Radiolarians, Sponge-spicules 

 and glauconitic casts of Foraminifera, etc. The finer washings 

 are greenish owing to some material not yet investigated, like 

 those obtained by the " Challenger " from similar depths on the 

 coasts of Africa, Australia, Japan and China. Many of the de- 

 posits might be called Globigerina oozes. Besides these materials 

 there are concretions of calcium and manganese phosphate every- 

 where ; and one such from a depth of 333 fathoms, in 31° 57' N. 

 and 78° 18' 35" W., from over a hardish bottom, was nine inches 



