Download or read book Catalog of Books and Reports in the Bureau of Mines Technical Library Pittsburgh Pa written by United States. Bureau of Mines. Technical Library, Pittsburgh and published by . This book was released on 1968 with total page 778 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The National Union Catalog Pre 1956 Imprints written by Library of Congress and published by . This book was released on 1968 with total page 710 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book On the Aims and Methods of Biological History and Biography written by Charles Albert Browne and published by . This book was released on 1944 with total page 498 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book An Introduction to Pollen Analysis written by G. Erdtman and published by Read Books Ltd. This book was released on 2013-04-18 with total page 424 pages. Available in PDF, EPUB and Kindle. Book excerpt: It has long been the custom among those making pollen surveys to expose microscope slides coated with a suitable adhesive and examine them for the pollen grains caught. The counts of the various species are tabulated each day and at the end of the season drawn into a graph or pollen spectrum, as it is called , which gives a clear picture of the relative amounts of the different kinds of pollen which are floating in the air from day to day throughout the growing season If done in the north temperate zone such a spectrum will show the pollen of the early flowering trees, at first a trickle, as the junipers, alders and hazels flower, then a deluge as the birches, oaks and pines and many other trees cast their pollen to the air. This is generally followed by a long stream of grass pollen, fluctuating from week to week as the various species come into flower, reach their zenith, then die out giving way to succeeding species And toward the end of the summer pollens of the late flowering weeds make their appearance, nowadays in most places completely dominated by that of the ragweed. If the record is repeated the following year the spectrum will be nearly the same The succession can be counted on to repeat itself with subtle change from year to year for many years to come, unless some cataclysm changes the surrounding vegetation which contributes to the pollen spectrum, for it is always a faithful representation of the surrounding vegetation.
Download or read book Chronica Botanica written by and published by . This book was released on 1935 with total page 496 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Research Catalogue of the American Geographical Society written by American Geographical Society of New York and published by . This book was released on 1962 with total page 1034 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Science written by John Michels (Journalist) and published by . This book was released on 1944 with total page 622 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Journal of Paleontology written by Hans Ernst Thalmann and published by . This book was released on 1944 with total page 696 pages. Available in PDF, EPUB and Kindle. Book excerpt: Vols. 7-10, 12-13, 15-17 include section "Bibliography and index to new genera, species and varieties of Foraminifera" (varies) by H. E. Thalmann.
Download or read book Research Catalogue of the American Geographical Society General topical numbers 5 9 Human Geography History of Geography Geographical Teaching Aids to Geographical Study History written by American Geographical Society of New York and published by . This book was released on 1962 with total page 1038 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Geology of the Green River Desert cataract Canyon Region written by Arthur Alan Baker and published by . This book was released on 1946 with total page 858 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Research Catalogue written by American Geographical Society of New York and published by . This book was released on 1962 with total page 1036 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Chronica Botanica written by Frans Verdoorn and published by . This book was released on 1947 with total page 134 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The National Union Catalog written by and published by . This book was released on 1961 with total page 652 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Garden Flowers of China written by Hui-Lin Li and published by . This book was released on 1959 with total page 524 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Catalog of Books and Reports in the Bureau of Mines Technical Library Pittsburgh Pa written by United States. Bureau of Mines. Technical Library, Pittsburgh and published by . This book was released on 1968 with total page 792 pages. Available in PDF, EPUB and Kindle. Book excerpt:
