This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1921 Excerpt: ...(s5).--By variability is understood the fact that the individuals belonging to any species are not all alike. Frequently the variability is only apparent, the species not having been properly denned. Thus in Rosa, Riibus, Draba verna, etc., there are many species that closely resemble one another. The impression given ...
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This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1921 Excerpt: ...(s5).--By variability is understood the fact that the individuals belonging to any species are not all alike. Frequently the variability is only apparent, the species not having been properly denned. Thus in Rosa, Riibus, Draba verna, etc., there are many species that closely resemble one another. The impression given of a "varying" species is in these cases a completely false one; each of the "ELEMENTARY SPECIES," of which the "COLLECTIVE SPECIES" is composed, proves to be constant and does not exhibit transitions to the other elementary species. Such cases are to be left out of consideration here. We are concerned with the most strictly limited species, if possible with the descendants of a single self-fertilised plant constituting what is known as a pure line (JOHANNSEN). It is found that these also vary. The process of variation and the varieties can be traced to two causes and are therefore distinguished as MODIFICATIONS and MUTATIONS. To these must be added the combinations originating from crossing. Modifications.--This name is given to variations which have gated into pure red and pure white sexual elements. In the process of fertilisation the union producing a hybrid, red x white (white $ x red, red 9 x white $ ), will occur twice as frequently as the union red x red or white x white, which give rise to pure forms. 2. Rule Of Dominance.--The characters in which the parents differ do not, however, always blend so that the hybrid exhibits an intermediate character. More usually the hybrids completely resemble in this respect either the paternal or maternal parent, the character of the one parent being dominant in the hybrid while the Fin. 269.--The hybrid between Vrtica piluHftra and Urtim Dotlnrtii in three gener...
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Add this copy of Strasburger's Text-Book of Botany to cart. $30.01, new condition, Sold by Ingram Customer Returns Center rated 5.0 out of 5 stars, ships from NV, USA, published 2022 by Legare Street Press.
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Add this copy of Strasburger's Text-Book of Botany to cart. $115.03, new condition, Sold by Bonita rated 4.0 out of 5 stars, ships from Newport Coast, CA, UNITED STATES, published 2022 by Legare Street Press.
