JULY, 190S.] 



51 



MISCELLANEOUS. 



THE DIFFERENCES BETWEEN WILD 

 AND CULTIVATIED PLANTS. 



By R. H. Lock. 



That the cultivated products of Ceylon, or 

 indeed of any other tropical country, do not 

 exhibit anything like so marked a contrast 

 with its wild vegetation as would be shown 

 by the corresponding plant-life in Europe or 

 North America, is a fact which maybe regard- 

 ed as a measure of the relative development 

 of the art of plant improvement in the two 

 regions thus compared. If we were to con- 

 sider the products of the tropics generally, the 

 contrast between wild and cultivated would 

 be still less noticeable than if we confined 

 our attention to Ceylon, for the reason that 

 so many of the plants cultivated in Ceylon 

 are introductions from other tropical coun- 

 tries, whilst some have been introduced from 

 subtropical and even temperate regions. In 

 Ceylon therefore the difference between wild 

 and cultivated plants depends rather on the 

 latter having been brought from distant 

 countries than on any inherent character- 

 istics of the cultivated plants themselves. 



In any limited tract of country, whether 

 temperate or tropical, the presence of intro- 

 ductions will naturally affect the character 

 of the cultivated vegetation to a more or 

 less marked extent ; but this feature of cul- 

 tivation is not the one to which I wish to 

 draw particular attention at present. The 

 point which it is now desired to discuss 

 relates rather to the differences in form and 

 structure between wild plants generally on 

 the one hand and those of their relatives on 

 the other, which have endured man's modify- 

 ing influence for considerable periods of time. 

 From this point of view we shall be compelled 

 to draw our examples chiefly from temperate 

 agriculture and horticulture, whilst reference 

 may be made in passing to the numerous 

 excellent instances of an analogous nature 

 which are to be found among domestic 

 animals. 



One of the best instances which can be 

 found of the changes associated with cultiva- 

 tion is afforded by the various kinds of 

 cabbage, all of which are almost certainly 

 descended from one or a few closely allied 

 species, none of which show any hint of the 

 remarkable features now to be described. 

 Odinary cabbages, red and green, have the 

 terminal bud developed into an enormous 

 fleshy head. In Brussels-sprouts all the buds 

 have undergone the same modifications, and 

 a number of little heads is the result. 

 Broccolis and cauliflowers have most of their 

 flowers aborted and incapable of producing 



seed, the whole mass of flowers being swollen 

 up into a great edible fleshy mass. Savoy 

 cabbages, again, have the leaves very much 

 wrinkled. Finally, in the Kohlrabi it is the 

 stem which is enlarged and edible. Notice 

 that in every case the difference from the 

 original wild form is one which is useful 

 to man, but highly prejudicial to the plant 

 itself from the point of view of its survival 

 in a natural habitat. No instance has ever 

 been recorded of a cauliflower or a Brussels- 

 sprout running wild, or even continuing to 

 exist without the gai'dener's constant assis- 

 tance. 



If now we consider a part of the cabbage 

 plant which is not made any use of by the 

 cultivator, we shall find that it shows scarcely 

 any difference from the same part in the 

 original wild plant. This is the case for 

 instance with the flowers and seeds. These 

 organs in all the different types of vegetable 

 enumerated above are almost exactly alike, 

 and also scarcely distinguishable from those 

 of the wild Brassica oleracea, this being in 

 fact the reason for supposing the latter plant 

 to be the original ancestor of all of them. 



If we now turn to consider a plant, the 

 seeds of which are used as a source of food, 

 we shall find the most marked diversity in 

 these organs, but very little in other 

 parts of the plant. This is the case, for 

 instance, with maize or Indian corn. The 

 leaves, stems and roots of the different 

 varieties of corn show only the slightest 

 differences, the seeds exhibit an extraordinary 

 diversity. Take first the differences in size. 

 Among samples of only a dozen kinds which 

 I lately recieved from America, I find that 

 five grains of a variety of pop-corn are re- 

 quired to balance one grain of a variety of 

 dent corn. The colour of the grains may be 

 white, pale yellow, orange, dark red, violet 

 or black, and may be either uniform or 

 mottled. The shape may be pointed, rounded, 

 indented or wrinkled at the apex. Great 

 differences also occur in the hardness, con- 

 sistency, and chemical composition. By 

 crossing together different varieties any con- 

 ceivable combination of the above characters 

 can' be obtained in a stable form. Nothing 

 remotely approaching this diversity is to be 

 found in the seeds or grains of any wild 

 plant. In wild plants differences infinitely 

 less than these are constantly associated 

 with some degree of sterility on crossing, 

 whereas all the varieties of maize which 1 

 have had an opportunity of testing are 

 perfectly fertile together. 



A precisely similar state of things is to 

 be observed when wild and domesticated 

 animals are compared together. Highly 

 bred strains of pigs, or sheep, or cattle are 

 extraordinarily ill-adapted for existence 



