The manner in which the tubers are arranged on the so-called roots or rhizomes is different; thus, in the gurken-kartoffeln they form a pyramid with the apex downwards, and in another variety they bury themselves deep in the ground. The roots themselves run either near the surface or deep in the ground. The tubers also differ in smoothness and colour, being externally white, red, purple, or almost black, and internally white, yellow, or almost black. They differ in flavour and quality, being either waxy or mealy; in their period of maturity, and in their capacity for long preservation.
As with many other plants which have been long propagated by bulbs, tubers, cuttings, etc., by which means the same individual is exposed during a length of time to diversified conditions, seedling potatoes generally display innumerable slight differences. Several varieties, even when propagated by tubers, are far from constant, as will be seen in the chapter on Bud-variation. Dr. Anderson (9/100. 'Bath Society Agricult. Papers' volume 5 page 127. And 'Recreations in Agriculture' volume 5 page 86.) procured seed from an Irish purple potato, which grew far from any other kind, so that it could not at least in this generation have been crossed, yet the many seedlings varied in almost every possible respect, so that "scarcely two plants were exactly alike." Some of the plants which closely resembled each other above ground, produced extremely dissimilar tubers; and some tubers which externally could hardly be distinguished, differed widely in quality when cooked. Even in this case of extreme variability, the parent-stock had some influence on the progeny, for the greater number of the seedlings resembled in some degree the parent Irish potato. Kidney potatoes must be ranked amongst the most highly cultivated and artificial races; nevertheless their peculiarities can often be strictly propagated by seed. A great authority, Mr. Rivers (9/101. 'Gardener's Chronicle' 1863 page 643.) states that "seedlings from the ash-leaved kidney always bear a strong resemblance to their parent. Seedlings from the fluke-kidney are still more remarkable for their adherence to their parent stock, for, on closely observing a great number during two seasons, I have not been able to observe the least difference, either in earliness, productiveness, or in the size or shape of their tubers."
CHAPTER 1.X.
PLANTS continued--FRUITS--ORNAMENTAL TREES--FLOWERS.
FRUITS.
GRAPES. VARY IN ODD AND TRIFLING PARTICULARS.
MULBERRY.
THE ORANGE GROUP. SINGULAR RESULTS FROM CROSSING.
PEACH AND NECTARINE. BUD-VARIATION. ANALOGOUS VARIATION. RELATION TO THE ALMOND.
APRICOT.
PLUMS. VARIATION IN THEIR STONES.
CHERRIES. SINGULAR VARIETIES OF.
APPLE.
PEAR.
STRAWBERRY. INTERBLENDING OF THE ORIGINAL FORMS.
GOOSEBERRY. STEADY INCREASE IN SIZE OF THE FRUIT. VARIETIES OF.
WALNUT. NUT.
CUCURBITACEOUS PLANTS. WONDERFUL VARIATION OF.
ORNAMENTAL TREES. THEIR VARIATION IN DEGREE AND KIND. ASH-TREE. SCOTCH-FIR. HAWTHORN.
FLOWERS. MULTIPLE ORIGIN OF MANY KINDS. VARIATION IN CONSTITUTIONAL PECULIARITIES. KIND OF VARIATION. ROSES. SEVERAL SPECIES CULTIVATED. PANSY. DAHLIA. HYACINTH. HISTORY AND VARIATION OF.
[THE VINE (Vitis vinifera) (Grapes).
The best authorities consider all our grapes as the descendants of one species which now grows wild in western Asia, which grew wild during the Bronze age in Italy (10/1. Heer 'Pflanzen der Pfahlbauten' 1866 s. 28.), and which has recently been found fossil in a tufaceous deposit in the south of France. (10/2. Alph. De Candolle 'Geograph. Bot.' page 872; Dr. A. Targioni-Tozzetti in 'Jour. Hort. Soc.' vol 9 page 133. For the fossil vine found by Dr. G. Planchon see 'Nat. Hist. Review' 1865 April page 224. See also the valuable works of M. de Saporta on the 'Tertiary Plants of France.') Some authors, however, entertain much doubt about the single parentage of our cultivated varieties, owing to the number of semi-wild forms found in Southern Europe, especially as described by Clemente (10/3. Godron 'De l'Espece' tome 2 page 100.) in a forest in Spain; but as the grape sows itself freely in Southern Europe, and as several of the chief kinds transmit their characters by seed (10/4.