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Comparison with 1866
Text in this page (from paragraph 5300, sentence 010, word 1 to paragraph 5300, sentence 010, word 11) is not present in 1866
The meaning of rudimentary organs is often quite unmistakeable: for instance, there are beetles of the same genus (and even of the same species) resembling each other most closely in all respects, one of which will have full-sized wings, and another mere rudiments of membrane; and here it is impossible to doubt, that the rudiments represent wings. Rudimentary organs sometimes retain their potentiality, and are merely not developed: this seems to be the case with the mammæ of male mammals, for many instances are on record of these organs having become well developed in full-grown males, and having secreted milk. So again there are normally four developed and two rudimentary teats in the udders of the genus Bos; but in our domestic cows the two sometimes become developed and give milk. In plants of the same species the petals sometimes occur as mere rudiments, and sometimes in a well-developed state. In some plants with their sexes separated, the male flowers include a rudiment of a pistil; and Kölreuter found that by crossing a species of this kind with another hermaphrodite species, the rudiment of the pistil in the hybrid offspring was much increased in size; and this clearly shows how essen- tially alike in nature the rudiment and the perfect pistil are. .. .. .. ..
Text in this page (from paragraph 5300, sentence 510 to paragraph 5300, sentence 540, word 5) is not present in 1866
Rudimentary organs declare their origin and plain meaning in various ways. ... There are beetles belonging to closely allied species, or even to the same identical species, which have either full-sized and perfect wings, or mere minute rudiments of membrane, not rarely lying under wing-covers firmly soldered together; and in this case it is impossible to doubt, that the rudiments represent wings. Rudimentary organs sometimes retain their potentiality: this occasionally occurs with the mammæ of male mammals, for they have been known to become well developed, and to secrete milk. So again ... in the udders in the genus Bos, there are normally four developed and two rudimentary teats; but the latter in our domestic cows sometimes become well developed and yield milk. In regard to plants the petals are sometimes rudimental, and sometimes well-developed in individuals of the same species. In certain diœcious plants Kölreuter found that by crossing a species, in which the male flowers included a rudiment of a pistil, with an hermaphrodite species, having of course a well-developed pistil, the rudiment in the hybrid offspring was much increased in size; and this clearly shows that the rudimentary and .. perfect pistils are essentially alike in nature. An animal may possess various parts in a perfect state, and yet they may in one sense be rudimentary, for they are useless: thus the tadpole of the common Salamander or newt, as Mr. G. H. Lewes remarks, "has gills, and passes its existence "in the water; but the Salamandra atra, which lives "high up among the mountains, brings forth its young "full-formed. This animal never lives in the water. "Yet if we open a gravid female, we find tadpoles "inside her with exquisitely feathered gills; and when "placed in water they swim about like the tadpoles of the "water-newt. Obviously this aquatic organisation has