 | 1837 - 468 Seiten
...in the animal kingdom. This law requires that a heterogeneous or special structure, shall arise only out of one more homogeneous or general ; and this by a gradual change. The importance of this law appears to have been insisted on chiefly by Von Bär, who arrived at it... | |
 | William Gifford, Sir John Taylor Coleridge, John Gibson Lockhart, Whitwell Elwin, William Macpherson, William Smith, Sir John Murray IV, Rowland Edmund Prothero (Baron Ernle) - 1851 - 570 Seiten
...Animals, 1843, pp. 248, 371. The proposition by Von Baer — ' A heterogeneous or special structure arises out of one more homogeneous or general, and this by a gradual change' (Ueber Eatwielielungsqeschichte der TTiiere, 1837), is a principle which is illustrated in a remarkable... | |
 | William Benjamin Carpenter - 1838 - 530 Seiten
...by Von Bar, who first announced it in its present form. " A heterogenous or special structure arises out of one more homogeneous or general ; and this by a gradual change." The details which will be given in the second division of this work, — relative to the evolution... | |
 | J.C. LOUDON, F.L.S. H.S. & C - 1843 - 750 Seiten
...are more homogeneous, the higher more heterogeneous. A heterogeneous or special structure arises thus out of one more homogeneous or general, and this by a gradual change. When the different functions, however, are highly specialised, the general structure retains more or... | |
 | John Claudius Loudon - 1843 - 716 Seiten
...are more homogeneous, the higher more heterogeneous. A heterogeneous or special structure arises thus out of one more homogeneous or general, and this by a gradual change. When the different functions, however, are highly specialised, the general structure retains more or... | |
 | 1848 - 584 Seiten
...rather prematurely, although their correctness has been fully borne out by the subsequent discoveries. In the first of these papers, he works out the important...of the embryo, pointing out at the same time (as M. MilneEdwards has subsequently done) that this fact completely negatives the idea that the vertebrated... | |
 | 1848 - 602 Seiten
...important principle of Von Baer, — that "a • imuk- des Sciences Naturelles, NS Zool., loin, i, p. 65. heterogeneous or special structure can only arise...the history of the embryo, pointing out at the same fime (as M. MilneEdwards has subsequently done) that this fact completely negatives the idea that the... | |
 | 1848 - 486 Seiten
...the important principle of Von Baer, — that 'a heterogeneous or special structure can arise only out of one more homogeneous or general, and this by...pointing out at the same time (as M. Milne Edwards hns subsequently done) that this fact completely negatives the idea that the vertebrated animal ever... | |
 | William Benjamin Carpenter - 1851 - 1126 Seiten
...words of Von Bar, who first enunciated the doctriue,t — " A Jieterogeneom or special structure arises out of one more homogeneous or general, and this by a gradual change." In the subsequent portion of this treatise, there will be found such ample illustrations of this law,... | |
 | Robert Chambers - 1853 - 458 Seiten
...words of Yon Bar, who first enunciated the doctrine, " A heterogencous or special strueture arises out of one more homogeneous or general, and this by a gradual change." Thus, also, it must be clearly seen, the embryo of each grade of being passes through the general conditions... | |
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a heterogeneous or special structure can only arise out of one more homogeneous or general, and this by a gradual change ;' and applies this to the different directions of development, which present themselves in the primary subdivisions of the animal... 
