The American Naturalist, Volumul 11Essex Institute, 1877 |
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Pagina 24
... course in search of food . In this way large broods may migrate a long distance , from perhaps twenty to fifty miles . In about six or seven weeks they acquire wings . Experience shows that the western locust as soon as it is fledged ...
... course in search of food . In this way large broods may migrate a long distance , from perhaps twenty to fifty miles . In about six or seven weeks they acquire wings . Experience shows that the western locust as soon as it is fledged ...
Pagina 25
... course of their travels may be unconsciously stimulated by the sexual instincts and the desire to discover suitable places for egg - laying , a long and tedi- ous operation . It has been sufficiently shown that a swarm of locusts ...
... course of their travels may be unconsciously stimulated by the sexual instincts and the desire to discover suitable places for egg - laying , a long and tedi- ous operation . It has been sufficiently shown that a swarm of locusts ...
Pagina 26
... course of certain swarms from their breeding - places , and their probable destination , so that when a swarm starts from Montana or Wyoming , its arri- val in Colorado a week or a fortnight later may with some cer- tainty be predicted ...
... course of certain swarms from their breeding - places , and their probable destination , so that when a swarm starts from Montana or Wyoming , its arri- val in Colorado a week or a fortnight later may with some cer- tainty be predicted ...
Pagina 27
... course of their migrations is quite dependent on the direc- tion of the winds , while the course of the winds depend more or less on the season of the year . We may expect that future re- search over sufficient territory will show that ...
... course of their migrations is quite dependent on the direc- tion of the winds , while the course of the winds depend more or less on the season of the year . We may expect that future re- search over sufficient territory will show that ...
Pagina 41
... course at Cambridge , are probably new to the majority of those who purchase the present work . If Mr. Sprague has made the Wild Flowers of America a work which will be sought by all lovers of the beautiful , Professor Goodale has done ...
... course at Cambridge , are probably new to the majority of those who purchase the present work . If Mr. Sprague has made the Wild Flowers of America a work which will be sought by all lovers of the beautiful , Professor Goodale has done ...
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Termeni și expresii frecvente
abundant Algæ American ancient animals antennæ appear archæology Arctic birds bones butterflies cañons cells character coast color Colorado contain Coryphodon Cretaceous Crustacea deposits distribution domestic turkey east eggs ELLIOTT COUES Eocene exhibited existence exploration fact fauna feet female Figure fishes flora flowers formation fossil genera genus Geographical geological geologist glacial habits hundred imaginal discs inches Indians insects interesting Island Key West Killingworth Lake land larvæ Lepidoptera living locust male mammals mass microscope migrations miles Miocene Mountains Museum NATURALIST northern O. C. Marsh object observed organs origin paper peculiar period plants plates Pliocene portion present probably Prof Professor recent region River rocks sand scientific seen sepals shells side Society species specimens stone structure surface Survey Tertiary theory tion trees tribes uniformitarian valley vegetation W. H. Dall
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Pagina 219 - I do not wish to particularise, but I dare say many of you, seeking knowledge, or in the laudable desire to employ a holiday usefully, have visited some great natural history museum. You have walked through a quarter of a mile of animals, more or less well stuffed, with their long names written out underneath them; and, unless your experience is very different from that of most people, the upshot of it all is that you leave that splendid pile with sore feet, a bad headache, and a general idea that...
Pagina 276 - The people are somewhat white, they wear apparel, and lie in beds, their weapons are bows, they have emeralds and other jewels, although they esteem none so much ,as turquoises, wherewith they adorn the walls of the porches of their houses, and their apparel and vessels, and they use them instead of money through all the country.
Pagina 467 - I look at the geological record as a history of the world imperfectly kept, and written in a changing dialect; of this history we possess the last volume alone, relating only to two or three countries. Of this volume, only here and there a short chapter has been preserved ; and of each page, only here and there a few lines.
Pagina 214 - In an Englishman's mouth it generally means that by which we get pudding or praise, or both. I have no doubt that is one meaning of the word utility, but it by no means includes all I mean by utility. I think that knowledge of every kind is useful in proportion as it tends to give people right ideas, which are essential to the foundation of right practice, and to remove wrong ideas, which are the no less essential foundations and fertile mothers of every description of error in practice. And inasmuch...
Pagina 719 - Darwin as to the display of color and ornaments by the male birds, there is a total absence of any evidence that the females admire or even notice this display. The hen, the turkey, and the pea-fowl, go on feeding while the male is displaying his finery, and there is reason to believe that it is his persistency and energy rather than his beauty which wins the day.
Pagina 715 - ... colour-variations either to one sex only or to both sexes ; the difference depending on some unknown law, and not being due to natural selection. I have long held this portion of Mr. Darwin's theory to be erroneous ; and have argued that the primary cause of sexual diversity of colour was the need of protection, repressing in the female those bright colours which are normally produced in both sexes by general laws ; and I have attempted to explain many of the more difficult cases on this principle....
Pagina 9 - After much consideration, and with assuredly no bias against Mr. Darwin's views, it is our clear conviction that, as the evidence stands, it is not absolutely proven that a group of animals, having all the characters exhibited by species in Nature, has ever been originated by selection, whether artificial or natural.
Pagina 446 - The International Exhibition to be held at Paris in 1878 will furnish such an occasion, and it is proposed to invite to that end governmental geological surveys, learned societies and private individuals throughout the world, to send to Paris such collections as will make the geological department of that exhibition as complete as possible. In order to take advantage of the collections which may thus be brought together, it is moreover proposed to convoke an International...
Pagina 467 - ... circumstances, and the blank intervals between the successive stages as having been of vast duration. But we shall be able to gauge with some security the duration of these intervals by a comparison of the preceding and succeeding organic forms. We must be cautious in attempting to correlate as strictly contemporaneous two formations, which include few identical species, by the general succession of their forms of life.
Pagina 114 - The Rocky Mountain locust or grasshopper, being the report of proceedings of a conference of the Governors of several Western States and Territories, together with several other gentlemen, held at Omaha, Nebr., on the 25th and 26th days of October, 1876, to consider the locust problem ; also a summary of the best means now known for counteracting the evil.