The American Naturalist

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Essex Institute, 1921 - Biology

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Page 91 - It is well to avoid the introduction of new generic names which differ from generic names already in use only in termination or in a slight variation in spelling which might lead to confusion. But when once introduced, such names are not to be rejected on this account.
Page 134 - Myricaceae) and one that occurs under decaying bark of chestnut, but cites no zoophagous forms. Janetiella occurs in Europe and both North and South America. The parasites proved to be of much greater interest than had been 1 Contribution from the Entomological Laboratory of the Bussey Institution, Harvard University, No. 196. anticipated, due not only to their strangely modified egg-laying apparatus but on account of a type of variation which they exhibit that appears to be quite different from...
Page 288 - Illustrated magazine, established in 1872, devoted to the diffusion of science, publishing articles by leading authorities in all departments of pure and applied science, including the applications of science to education and society. Annual subscription...
Page 192 - A weekly journal, which began publication on January 2, 1915, covering the field of education in relation to the problems of American democracy. Its objects are the advancement of education as a science and the adjustment of our lower and higher schools to the needs of modem life.
Page 109 - Taking into account the method of embryological development, however— the relation of lens, optic cup and choroid fissure— the defects are probably all attributable to the early injury of the lens. In some cases, both among originals and descendants, an eye microphthalmic at birth may undergo further degeneration such as collapse of the ball and what appears to be a resorption as if some solvent were operating upon it. The eyes of the mothers apparently remained unaffected. This is probably due...
Page 109 - ... through breeding. So far we have succeeded in passing it to the sixth generation. There seems to be no reason why it will not go on indefinitely since the imperfection tends to become worse in succeeding generations and also to occur in a proportionally greater number of young. The transmission was not infrequently of an irregular unilateral type, sometimes only the right, at others only the left eye showing the defect. In later generations there was an increasing number of young which had both...
Page 249 - Notice of a Collection of Nudibranchiate Mollusca made in India by Walter Elliot, Esq., with Descriptions of several New Genera and Species.
Page 169 - Next he proceeded to put three great baskets' into a boat, one at each end and the third in the middle, and then he let the water-fowl loose. Straightway they began to dive into the water, catching great numbers of fish, and ever as they caught them putting them of their own accord into the baskets, so that before long all the three baskets were full. And mine host then took the cord off their necks and let them dive again to catch fish for their own food. And when they had thus fed they returned...
Page 12 - The appearance of chromosomes is not to me suggestive of strings of beads of extreme heterogeneity, but rather of strands of some more or less homogeneous substance ; and in so far as numerical and geometrical order is exhibited by them, it would, in my opinion, be more proper to compare this regularity with that seen, for example, in drying mud or in the formation of prisms of basalt than to attribute to it a more fundamental meaning.
Page 109 - ... in not one of the forty-eight controls obtained from mothers which had been treated with unsensitized fowlserum or with fowl-serum sensitized to rabbit tissue other than lens, was there evidence of eye-defects, and I may add, that among the hundred or more young obtained later from mothers which were being experimented upon with various types of sera or protein extracts, for other purposes, not a single case of eye-defect has appeared.

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