40 BULLETIN OF THE 



Residue, 96.54 per cent, gray, consists of Minerals [80.00], m. di. 0.4 mm., 

 fragments of milky and hyaline quartz 1 to 2 mm. in diameter, felspar, horn- 

 blende, mica, glaucouite, augite, fragments of ancient rocks, and fragments of 

 serpentine rocks much decomposed. Siliceous organisms [6.00], Sponge spicules, 

 a few Radiolarians and Diatoms. Fine washings [10.54], green argillaceous mat- 

 ter with glauconitic particles, fine minerals, and fragments of Sponge spicules and 

 Diatoms. 



Station 340. — Lat. 39° 25' 30" N. Long. 70° 58' 40" W. Depth, 1394 

 fathoms. Surf. temp. 76|°. Bot. temp. 38°. A gray mud, coherent, plastic, 

 dries into hard lumps. 



Carbonate of Calcium, 16.81 per cent, consists of coccoliths and coccospheres, 

 otoliths of fish, fragments of Dentalium and Echinoderms, and the following 

 Foraminifera : — 



Glohigerina. bulloides, few. Rotalia repanda, rare. 



G. inflata, few. Truncatulina lobatula, few. 



G. dubia, few. Uvigerina pi/gmaa, few. 



G. rubra, few. Bulimina marginata, rare. 



Puhinulina menardii (dwarfed), rare. Nonionina umbilicatula, rare. 



P. micheliniana, rare. Biloculina ringens (dwarfed), rare. 



P. elegans, rare. 



Residue, 83.19 per cent, dark brown, consists of Minerals [40.00], m. di. 

 0.3 mm.," quartz, felspar, mica, hornblende, magnetite, olivine, glauconite, glassy 

 fragments. Siliceous organisms [5.00], Diatoms, Radiolarians, and Sponge spi- 

 cules. Fin^ washings [38.19], argillaceous matter, fine mineral particles, and 

 fragments of siliceous organisms. 



2. Specimens of deposits procured off the Coast of the United States 

 between Cape Hatteras and Lat. 31° 48' N. 



These deposits are green muds or sands. They are with two excep- 

 tions under 1,000 fathoms, and are mostly under the waters of the Gulf 

 Stream, or along its inner margin. The mineral particles are much 

 the same as those in the deposits north of Cape Hatteras, but are all 

 very much smaller, and have evidently not been transported by ice. 

 The mineral particles, with the exception of the concretions formed at 

 the bottom, seldom exceed 0.4 mm. in diameter, and consist of quartz, 

 felspars, augite, hornblende, magnetite, and a few fragments of glassy 

 rocks. Glauconitic grains and casts are frequently very abundant, as 

 are also grains of manganese peroxide. 



The carbonate of lime makes up usually over 50 per cent of the 

 whole deposit, and consists chiefly of the dead shells of pelagic Forami- 

 nifera, along with shells of pelagic Mollusks, fragments of Echinoderms, 



