The American Naturalist, Volume 30Essex Institute, 1896 - Biology |
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Page 48
... species . A complete skeleton ( number 11,022 ) and a second specimen with the most of the limb bones and a skull lacking the man- dible ( number 11,372 ) , both in the Princeton Museum , enable me to determine the skull of this species ...
... species . A complete skeleton ( number 11,022 ) and a second specimen with the most of the limb bones and a skull lacking the man- dible ( number 11,372 ) , both in the Princeton Museum , enable me to determine the skull of this species ...
Page 49
... species of Machairodonts , it is taken as representative of H. primaevus . In the Princeton collection there is a fairly complete skull ( number 11,013 ) and two nearly complete skeletons ( numbers 10,741 and 10,934 ) , with the latter ...
... species of Machairodonts , it is taken as representative of H. primaevus . In the Princeton collection there is a fairly complete skull ( number 11,013 ) and two nearly complete skeletons ( numbers 10,741 and 10,934 ) , with the latter ...
Page 71
... species , distributed as follows ; Chel- onia 10 , Loricata 3 , Sauria 57 , Ophidia 74 , Batrachia 41. Of the spec- imens described , 62 species and varieties belong exclusively to the fauna of Angola and Congo . In order to better ...
... species , distributed as follows ; Chel- onia 10 , Loricata 3 , Sauria 57 , Ophidia 74 , Batrachia 41. Of the spec- imens described , 62 species and varieties belong exclusively to the fauna of Angola and Congo . In order to better ...
Page 80
... species larvæ of all sizes down to 2 % of the normal were found . 2. When pieces that contain no nucleus , as far as could be seen under the microscope , were isolated and fertilized with sperm of the same species they developed into ...
... species larvæ of all sizes down to 2 % of the normal were found . 2. When pieces that contain no nucleus , as far as could be seen under the microscope , were isolated and fertilized with sperm of the same species they developed into ...
Page 103
... species type , which by no means precludes the presence of anatomical differences . And these anatomical differences may indicate little relation- ship , in spite of the general resemblance of the species con- cerned , or they may have ...
... species type , which by no means precludes the presence of anatomical differences . And these anatomical differences may indicate little relation- ship , in spite of the general resemblance of the species con- cerned , or they may have ...
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acid adaptations Amer American animals appear augite bacteria beds beets birds body bones Botany brain Bull cells characters color containing Cope described diabases Diplopoda disease eggs embryo Eocene evidence evolution experiments Extr fact fauna fishes formation fossil gabbro gastrula gelatine genera genus Geol Geological gneisses heredity hornblende Hyracotherium insects known Lacertilia larvæ latter legs length less limestone mass ment method mineral molars movements Museum mushroom bodies natural NATURALIST North observed occur organism original orthoclase ovum Paleontology paper paroccipital phenocrysts plagioclase plants plates porphyritic premolar present probably Prof Professor protoplasm quartz recent region relation rocks Science segment selection side skull species specimens spores sporophylls squamosal stage stain stem structure subspecies substance surface tail tion tissues University upper variations vegetative
Popular passages
Page 911 - Its power of inducing fermentation in a solution of sugar was entirely destroyed, although no perceptible change in the appearance of the yeast cells could be detected under the microscope. This experiment was repeated several times, and always with the same result, although when the yeast was simply washed in water it readily induced fermentation.
Page 189 - Consequently, if the theory be true, it is indisputable that before the lowest Cambrian stratum was deposited, long periods elapsed, as long as, or probably far longer than, the whole interval from the Cambrian age to the present day; and that during these vast periods the world swarmed with living creatures.
Page 552 - Does the organism learn to make new adjustments, or to modify old ones, in accordance with the results of its own individual experience? If it does so, the fact cannot be due merely to reflex action in the sense above described, for it is impossible that heredity can have provided in advance for innovations upon, or alterations of, its machinery during the lifetime of a particular individual.
Page 431 - Their houses are mats or barks of trees, set on poles in the fashion of an English barn, but out of the power of the winds, for they are hardly higher than a man.
Page 169 - Illustrations of the dynamic metamorphism of anorthosites and related rocks in the Adirondacks...
Page 862 - Assistant Secretary of the Smithsonian Institution and Director of the National Museum, died in Washington, Sept.
Page 409 - Triarthrus. No traces of any special organs for this purpose have been found in this genus, and their former existence is very doubtful, especially in view of the perfection of details preserved in various parts of the animal. The delicacy of the appendages and ventral membrane of trilobites and their rarity of preservation are sufficient demonstration that these portions of the outer integument were of extreme thinness, and therefore perfectly capable of performing the function of respiration. Similar...
Page 544 - Naturalist. [July, ments) — but by the reinstatement of it by a discharge of the energies of the organism, concentrated as far as may be for the excessive stimulation of the organs (muscles, etc.) most nearly fitted by former habit to get this stimulation again (in which the " stimulation " stands for the condition favorable to adaptation).
Page 994 - We must therefore picture to ourselves a fertile plain occupying the whole of the Bristol Channel, and supporting herds of reindeer, horses, and bisons, many elephants and rhinoceroses, and now and then being traversed by a stray hippopotamus, which would afford abundant prey to the lions, bears, and hyaenas, inhabiting all the accessible caves, as well as to their great enemy and destroyer, man."* III.
Page 940 - In reviewing the results of these investigations and comparing one species with another, without losing sight of the fact that comparative good is not necessarily positive good, it appears that of 7 species considered the Downy Woodpecker is the most beneficial. This is due in part to the great number of insects it eats and in part to the nature of its vegetable food, which is of little value to man. Three-fourths of its food consists of insects, and few of these are useful kinds. Of grain, it eats...