34 THE CANADIAN NATURALIST. [Feb. 



and that probably some day, at no very distant period, we shall 

 know in a spontaneous state the immense majority, perhaps the 

 totality of our cultivated species. 



M. Alphonse de Candolle gives a list of 157 j)lants, which he 

 selects, because most commonly cultivated by man, and of these 

 eighty-five have been found wild— that is to say, identical with the 

 cultivated plant, or at least with some of its varieties. If to these 

 species are added those which are most probably wild, or about 

 which hardly a doubt remains, we may consider 117 as having 

 been identified in a spontaneous state. In short, the species which 

 we historically know to have been first cultivated in Europe, have 

 been found wild in Europe ; and those cultivated species of which 

 the wild form has not yet been found, are all foreign plants culti- 

 vated abroad, and in countries which have not yet been explored. 



Having made these introductory remarks, we now confine our- 

 selves to an inquiry into the origin of the kitchen-garden plants of 

 the United Kingdom. We select for this purpose such vegetables 

 as are in ordinary use during winter ; in fact, our common Christ- 

 mas vegetables will furnish an abundance of interesting material 

 for discussion. 



Our kitchen-garden plants may be sub-divided into — 1 . Those 

 plants which are cultivated for the nutritive material in their rhi- 

 zome, as the potato, parsnip, carrot, turnip, and horseradish. 

 2. Those plants which are cultivated for their stems, leaves, and 

 flowers, as celery and the different varieties of the garden cabbage. 

 We begin with that well-known vegetable, 



The Potato (Solanum tuberosum, L.) — This plant belongs to 

 the natural order Solanaceae, and is closely related to the tobacco- 

 plant, belladonna, henbane, nightshade, and other poisonous nar- 

 cotics. But although the same poisonous principle exists in the 

 potato-plant, it is confined to its stem, foliage, and fruit, and is 

 wholly absent from its roots or underground tubers, the part of the 

 plant used as food. When potatoes still attached to the growing 

 plant become exposed to the light, the epidermis assumes a green- 

 ish color, and the poisonous principle then develops itself. Such 

 potatoes are totally unfit for human food. The potato-plant has a 

 stem from one and a half to two feet high, with interrupted pin- 

 nate leaves, which are composed of from five to seven pairs of lan- 

 ceolate oval leaflets, having lesser ones between them; the flowers 

 are bluish-white, with orange yellow, slightly cohering anthers, 

 which are succeeded by a green globose berry, about half an inch 



