532 



NATURE 



[October i, 1891 



a species when it seems to be peculiarly susceptible to the 

 influences of surroundings. A species, like a carefully laden 

 ship, represents a balancing of forces within and without. 

 Disturbance may come through variation from within, as from a 

 shifting of the cargo, or in some cases from without. We 

 may suppose both forces to be active in producing variation, 

 a change in the internal condition rendering the plant more 

 susceptible to any change in its surroundings. Under the 

 influence of any marked disturbance, a state of unstable equili- 

 brium may be brought about, at which times the species as such 

 is easily acted upon by very slight agencies. 



One of the most marked of these derangements is a consequent 

 of cross-breeding within the extreme limits of varieties. The 

 resultant forms in such cases can persist only by close breeding 

 or by propagation from buds or the equivalents of buds. Dis- 

 turbances like these arise unexpectedly in the ordinary course of 

 nature, giving us sports of various kinds. These critical periods, 

 however, are not unwelcome, since skilful cultivators can take 

 advantage of them. In this very field much has been accom- 

 plished. An attentive study of the sagacious work done by 

 Thomas Andrew Knight shows to what extent this can be 

 done. But we must confess that it would be absolutely im- 

 possible to predict with certainty how long or how short would 

 l)e the time before new cereals or acceptable equivalents for 

 them would be provided. Upheld by the confidence which I 

 have in the intelligence, ingenuity, and energy of our experi- 

 ment stations, I may say that the time would not probably 

 exceed that of two generations of our race, or half a century. 



In now laying aside our hypothetical illustration, I venture to 

 ask why it is that our experiment stations, and other institutions 

 dealing with plants and their improvement, do not undertake 

 investigations like those which I have sketched ? Why are not 

 some of the grasses other than our present cereals studied with 

 reference to their adoption as food grains ? One of these species 

 will naturally suggest itself to you all — namely, the wild rice of 

 the lakes. Observations have shown that, were it not for the 

 difficulty of harvesting these grains, which fall too easily when 

 they are ripe, they might be utilized. But attentive search 

 might find or educe some variety of Zizania, with a more 

 persistent grain and a better yield. There are two of our sea- 

 shore grasses which have excellent grains, but are of small 

 yield. Why are not these, or better ones which might be 

 suggested by observation, taken in hand ? 



The reason is plain. We are all content to move along in 

 lines of least resistance, and are disinclined to make a fresh 

 start. It is merely leaving well enough alone, and so far as 

 the cereals are concerned it is indeed well enough. The 

 generous grains of modern varieties of wheat and barley com- 

 pared with the well-preserved charred vestiges found in Greece 

 by Schliemann, and in the lake-dwellings, are satisfactory in 

 every respect. Improvements, however, are making in many 

 directions ; and in the cereals we now have, we possess far 

 better and more satisfactory material for further improvement 

 both in quality and as regards range of distribution than we 

 could reasonably hope to have from other grasses. 



From the cereals we may turn to the interesting groups of 

 plants comprised under the general term 



II. Vegetables. 



Under this term it will be convenient for us to include all 

 plants which are employed for culinary purposes, or for table 

 use, such as salads and relishes. 



The potato and sweet potato, the pumpkin and squash, the 

 red or capsicum peppers, and the tomato, are of American 

 origin. 



All the others are, most probably, natives of the Old World. 

 Only one plant coming in this class has been derived from 

 Southern Australasia— namely. New Zealand spinach [Telra- 

 gonia). 



Among the vegetables and salad-plants longest in cultivation 

 we may enumerate the following : turnip, onion, cabbage, 

 purslane, the large bean (Faba), chick-pea, lentil, and one 

 species of pea (garden-pea). To these an antiquity of at least 

 4000 years is ascribed. 



Next to these, in point of age, come the radish, carrot, beet, 

 garlic, garden-cress, and celery, lettuce, asparagus, and the 

 leek. Three or four leguminous seeds are to be placed in the 

 same category, as are also the black peppers. 



Of more recent introduction the most prominent are : the 

 parsnip, oyster-plant, parsley, artichoke, endive, and spinach. 



NO. I 144, VOL. 44] 



From these lists I have purposely omitted a few which 

 belong exclusively to the tropics, such as certain yams. 



The number of varieties of these vegetables is astounding. 

 It is, of course, impossible to discriminate between closely 

 allied varieties which have been introduced by gardeners and 

 seedsmen under different names, but which are essentially 

 identical, and we must therefore have recourse to a conserva- 

 tive authority, Vilmorin, from whose work a few examples 

 have been selected. The varieties which he accepts are suffi- 

 ciently well distinguished to admit of description, and in most 

 instances of delineation, without any danger of confusion. 

 The potato has, he says, innumerable varieties, of which he 

 accepts forty as easily distinguishable and worthy of a place in 

 a general list ; but he adds also a list, comprising, of course, 

 synonyms, of thirty-two French, twenty-six English, nineteen 

 American, and eighteen German varieties. The following 

 numbers speak for themselves, all being selected in the same 

 careful manner as those of the potato : celery more than 

 twenty ; carrot more than thirty ; beet, radish, and potato, 

 more than forty ; lettuce and onion more than fifty ; turnip 

 more than seventy ; cabbage, kidney-bean, and garden pea, 

 more than one hundred. 



The amount of horticultural work which these numbers 

 represent is enormous. Each variety established as a race 

 (that is, a variety which comes true to seed) has been evolved 

 by the same sort of patient care and waiting which we have 

 seen is necessary in the case of cereals, but the time of waiting 

 has not been as a general thing so long. 



In the case of the cabbage there are important morphological 

 changes like those to which Prof. Bailey has called attention in 

 the case of the tomato. Suppose we are strolling along the 

 beach at some of the seaside resorts of France, and should fall in 

 with this coarse cruciferous plant, with its sprawling leaves and 

 strong odour. Would there be anything in its appearance to 

 lead us to search for its hidden merit as a food-plant? What 

 could we see in it which would give it a preference over a score 

 of other plants at our feet ? Again, suppose we are journeying 

 in the high lands of Peru, and should meet with a strong-smell- 

 ing plant of the nightshade family, bearing a small irregular 

 fruit, of sub-acid taste and of peculiar flavour. We will further 

 imagine that the peculiar taste strikes our fancy, and we conceive 

 that the plant has possibilities as a source of food. We should 

 be led by our knowledge of the potato, probably a native of the 

 same region, to think that this allied plant might be safely trans- 

 ferred to a northern climate, but would there be promise of 

 enough future usefulness, in such a case as this, to warrant our 

 carrying the plant north as an article of food ? Suppose, 

 further, we should ascertain that the fruit in question was 

 relished not only by the natives of its home, but that it had 

 found favour among the tribes of South Mexico and Central 

 America, and had been cultivated by them until it had attained 

 a large size ; should we be strengthened in our venture ? Let 

 us go one step further still. Suppose that, having decided upon 

 the introduction cf the plant, and having urged everybody to 

 try it, we should find it discarded as a fruit, but taking a place 

 in gardens as a curiosity under an absurd name, or as a basis for 

 preserves and pickles ; should we not look upon our experiment 

 in the introduction of this new plant as a failure ? This is not a 

 hypothetical case. 



The tomato, the plant in question, was cultivated in Europe 

 as long ago as 1554; it was known in Virginia in 1781 and in 

 the Northern States in 1785 ; but it found its way into favour 

 slowly, even in this land of its origin. A credible witness 

 states that in Salem it was almost impossible to induce people to 

 eat or even taste of the fruit. And yet, as you are well aware, 

 its present cultivation on an enormous scale in Europe and this 

 country is scarcely sufficient to meet the increasing demand. 



Before asking specifically in what direction we shall look for 

 new vegetables, I must be pardoned for calling attention, in 

 passing, to a very few of the many which are already in limited 

 use in Europe and this country, but which merit a wider em- 

 ployment. Cardon, or cardoon ; celeriac, or turnip-rooted 

 celery ; fetticus, or corn-salad ; martynia ; salsify ; sea-kale ; 

 and numerous small salads, are examples of neglected treasures 

 of the vegetable garden. 



The following, which are even less known, may be mentioned 

 as fairly promising ; — 



(i) Arr acacia esculenta, called Arracacha, belonging to the 

 parsley family. It is extensively cultivated in some of the 

 northern States of South America. The stems are swollen near 



