GeneticaJohannes Paulus Lotsy, Marius Jacob Sirks, Havik Nicolaas Kooiman Springer Netherlands, 1922 Includes section "Boekbesprekingen." |
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Стр. 8 - ... in a chromosome without disturbing its integrity, the number of chromosomes in related species thus remaining the same. On the other hand such additional genes may disturb the existing complex and cause the whole mass of genes to be entirely redistributed, thus causing a change in chromosome number in nearly related species. Should a certain group of genes be placed in one chromosome in one species and in two in another, there would not be necessarily any difference in these two species. It would...
Стр. 390 - ... If so, the astonishing variations of almost all cultivated plants must be due to selection and breeding from the varying individuals. This idea crossed my mind many years ago, but I was afraid to publish it, as I thought that people would say, " how he does exaggerate the importance of selection.
Стр. 386 - DEDICATION of a work entitled "Evolution — A Menace," by the Rev. JW Porter of Springfield: Dedicated to my beloved and womanly wife, on whose brow is stamped the likeness of Him in whose image she was created, and whose pure and noble blood is untainted by that of insect, reptile, fowl, or beast.
Стр. 524 - The correlation between length and breadth is not an expression of a biological relation between the two measurements, but an effect of the changes which both undergo when the capacity of the skull increases or decreases.
Стр. 457 - The interaction between two closely linked lethals in Drosophila as the cause of the apparent constancy of the mutant
Стр. 99 - ... one received the recessive character of the white colour, while in Pisum this occurs on the average in every fourth plant. Even these enigmatical results, however, might probably be explained by the law governing Pisum if we might assume that the colour of the flowers and seeds of Ph. multiflorus is a combination of two or more entirely independent colours, which individually act like any other constant character in the plant.
Стр. 18 - ... However, it is equally apparent that other numbers not resolvable into these factors are also of frequent occurrence. In using the present tabulation for any generalizations or conclusions, several facts must be taken into consideration. Many of the observations recorded are of too early a date to be of much value. Other observations are contradictory and in many cases it is impossible to judge which is correct; this is largely due to difficult material and is especially true for the mammals,...
Стр. 8 - type number.' The type number of a class of animals is the most frequently occurring number and may be considered tentatively as the fundamental chromosome group. One or more chromosomes of this group or of a group derived from it may split into two (or more) parts, or they may fuse, thus causing the differences in number which occur in related forms. Whether the double groups which occur in closely related forms in many plants (eg Oenothera gigas and O.
Стр. 8 - ... animals for the genes to segregate out according to some definite pattern. If, therefore, we make a list of all the chromosome numbers which have been reported for all the species of a certain class13 of Metazoa, leaving out of account results which are conflicting or are too old to be accurate, we find that a certain number of chromosomes is characteristic of that class; that is, there are considerably more species having that number of chromosomes than any other number. This I will call the...
Стр. 524 - ... both factors of the capacity of the head. So we find as a tendency, that an increasing length is accompanied by a relatively narrowing, an increasing breadth by a relatively shortening of the head (See also p. 522). TSCHEPOURKOWSKY (1905, p. 286) remarks that we do not find between the lengths and the breadths of skulls in the same race a relation which is in accordance with the principle of compensational growth. I suppose that in the sense as is illustrated here, he will not deny, that it is...