Feldspar is sparingly present, and includes both monoclinic and triclinic forms, whose crystallographic boundaries are invariably lacking. Treatment of the sand with dilute acid produces effervescence, which is not due to incrustations of sodium carbonate. By persistent search among particles separated in a heavy solution, a few grains were discovered which, from their complete solubility with offervescence in very dilute acid, as well as their optical properties, left no doubt as to their being calcite. The mica group has only one representative, biotite, and this occurs most sparingly. Though much of the sand was examined, but few fragments were found. Its foliated character renders it easily transported by water and explains its absence from among the heavy minerals. Shaly, slaty and schistose material forms the major part of the coarser grains. Thin sections from the largest pieces plainly indicated hornblende schist. A region of glaciers would seem to be favorable not only to the collertion of meteoric material, but also to the destruction of the country rocks, the setting free of their mineralogic constituents in a comparatively fresh state, and their transportation to the sea. It was hoped that this sand would yield some of the rarer varieties of minerals, but tests for native iron, platinum, chromite, gneiss, and the titaniferous minerals proved ineffectual. Titanium is present, but in such small quantities that it could only be detected by means of hydrogen peroxide. The use of acid supersulphate and the borotungstate of calcium test of Lasaulx failed to reveal the presence of native iron. It will be seen from the foregoing enumeration that the sand is made up of grains of gold, magnetite, garnet, hornblende, pyroxene, zircon, quartz, feldspar, calcite and mica, associated with fragments of a shaly, slaty and schistose character. While the information at hand is hardly sufficient to warrant much speculation concerning the rock masses of the interior, still there is no doubt that the sand is derived from the destruction of metamorphic rocks. APPENDIX D. REPORT ON FOSSIL PLANTS. BY LESTER F. WIRD. a DEPARTMENT OF THE INTERIOR, Washington, D. ('., Varch 12, 1891. Mr. I. C. RusSELL, United States Geological Surrey. My Dear Sir: The following report upon the small collection of fossil plants made by you at Pinnacle pass, near Mount St. Elias, Alaska, and sent to this division for identification has been prepared by Professor F. H. Knowlton, who gave the collection a careful stuly during my absence in Florida. Previous to going away I had somewhat hastily exaniined the specimens and seen that they consisted chiefly of the genus Salid, some of them reminding me strongly of living species. I have no doubt that Professor Knowlton's more thorough comparisons can be relied upon with as much confidence as the nature of the collection will permit, and I also agree with his conclusions. “The collection consists of seven small hand specimens, upon which are impressed no less than seventeen more or less completely preserved dicotyledonous leaves. “These specimens at first sight seem to represent six or eight species, but after a careful study I think I am safe in reducing the number to four, as several of the impressions have been nearly obliterated by prolonged exposure and cannot be studied with much satisfaction. “ The four determinable species belong, without much doubt, to the genus Salir. Number 1, of which there is but a single specimen, I have identified with Salix californica, Lesquereux, from the auriferous gravel deposits of the Sierra Nevada in California.* The finer nervation of the specimens from the auriferous gravels is not clearly shown in Lesquereux's figures, nor is it well preserved in the Mount St. Elias specimens; but the size, outline, and primary nervation are identical. "Number 2, of which there are six or eight specimens, may be compared with Salix racana, Heer,f a species that was first described from Greenland and was later detected by Lesquereux in a collection from (ooks inlet, Alaska. The Mount St. Elias specimens are not very much like the original figures of Heer, but are very similar, in outline at least, to this species as figured by Lesquereux. They are also very similar to * Mem. Mus. Comp. Zool., vol. VI, no. 2, 1878, p. 10, pl. i, figs. 18-21. | Flor. focs. Arct., vol. I, 1868, p. 102, pl. iv, figs. 11-13; pl. xlvii, fig. 11. Proc. Nat. Mus., vol. V, 1882, p. 447. è loc. cit., pl. viii, fig. 6. some forms of the living S. rostrata, Richardson, with entire leaves. It is clearly a willow, but closer identification must remain for more complete material. “ Number 3, represented by four or five specimens, is broadly elliptical in outline, and is also clearly a Salir. It is unlike any fossil form with which I am fimiliar, but is very similar to the living I. nigricans, For., var. rotundifolia, and to certain forms of S. silesiaca, Willd. The nervation is very distinctly preserved, and has all the characters of a willow leaf. “Number 4, represented by three or four very fine specimens, is a very large leaf, measuring 1:3 cm. in length and 3 cm in width at the broadlest point. It may be compared with Sulir macrophylla, Heer,* but it cannot be this species. It is also like some of the living forms of S. nigra, Marsh., from which it cliffers in having perfectly entire margins. “While it is manifestly impossible, on the basis of the above identifications, to speak with confidence as to the age or formation containing these leaves, it can hardly be older than the Miocene, and from its strong resemblance to the present existing flora of Alaska it is likely to be much younger." [F. II knowlton.] Very sincerely yours, LESTER F. WARD. * Tert. Fl. Helv., vol. II, 1836, p. 29, pl. Ixvii, fig. 4. Puge. 50 1447 73 175 176, 180 75 89, 114 92, 105 196, 197, 198 145, 155 63, 64 Page. 75 140 60 163 50 of.. 79 63 95, 115 75 146 85, 158, 159, 160, 162 55 60, 62 68, 69 Farenholt, Lieutenant Commander 0. F., Commander of U.S.S. Pinta..... 79 83, 136 118 105, 108 140 199, 200 Baie de Monti... 50 58 80 94, 109 by..... 75 75 56 75 75 79 166 75 1-14 73 140 06 113, 123, 162 75 163 181, 182 130 67 76 96, 103, 122, 125, 151 131, 135, 139 60 ....... 70, 72 73 107 75 Gabbro on the Marvine glacier 123 63 89, 90 ploration fund by 194 190, 191, 174 193, 19+ 187 183 183, 184 67 64, 65, 97 67, 68 176 187 75 73 Haerke, D. Tadeo, Haenke island 65 96, 103 75 Page. 75 110, 111 tion fund by...... SO, 83 112 112 1:33 118 56, 100 75 X3 70 75 99 Page. 71, 72 120, 121, 162 118, 119 62, 63 75 87 195 134 191 14.5 117 65 92 72 92 60 141 117 72 146 72 78, 79 GO National Geographic Society, Instruc- 194 180, 181, 182 154) 75 78 75 Oil stoves, Use of........ 164 70 69 165 95, 115 Kerr, Mark B., Assiyned as an assist- 75 79, 80 75 68 199, 200 58 58 73 119, 120 116 75 72, 73 76 149, 150, 153, 157, 158, 164 55 192 78 Panax horridum 76 158, 159, 162 176, 185, 186 120, 121 137 132 ............. 130, 132 130 131 GO 137 69 56 GO 75 79, 81 Malaspina, of....... Alejandro, Explorations 62, 66 |
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