SPORTS IN PLANTS, a term in biology denoting an individual which differs more or less markedly from the type or parent species; an aberrant form. It is distinguished from gmonstrosityl by its ability to transmit its aber rant character either sexually or asexually to offspring; whereas monstrosities properly so called lack this power, their offspring, if any, reverting to the general type. The origin of sports has furnished much food for speculation, some biologists assuming that aberrations are freaks which nature destroys, while others de clare that the transmutation of species is de pendent upon them through the processes of natural selection of the adaptive ones. If the term is to be used as an approximate synonym of monstrosity the first hypothesis is probably true; but if used in its broadest sense the latter is more nearly correct. The matter hinges mainly upon the extent of observation; for, while sports among undomesticated animals are comparatively rare, they are numerous among uncultivated plants, but have been commonly overlooked because biologists have been more awake to the animal than the plant. Each leaf bud of a plant is capable of producing leaves and branches which differ from those produced by any other bud, and every flower-bud may produce a flower unlike any of its fellows; nay, further, the individual seeds which follow any flower in a single fruit may produce plants unlike one another in many respects and also unlike the parent. But unless these departures are striking enough to attract the attention of the ordinary observer as distinct they are un noted and hence not calculated upon; hence the popular opinion that sports appear °suddenly,* since only the remarkable cases are observed.
They can be no doubt that sports result from unusual or complex stimuli or unaccount refrangibility of vegetative force, and for these reasons may be, usually are, unstable when normal conditions are again operative. However, this does not oppose but it rather en forces the statement that sports result from the same causes as underlie all variation• in the plant kingdom, bud-variation being one of the most important and significant phenomena of plantlife. But though the causes are usually un
known in plants and vertebrate animals, sports have been produced artificially with diverse lepidopterous insects by varying the humidity, dryness and temperature of the air during the process of growth or pupation. The crossing of the sports with the type-species does not usu ally result in an intermediate form but in two main groups, in one of which the offspring re semble the male parent and in the other the female.
From a practical standpoint, selection and breeding of sports has long been widely em ployed. Among domestic animals one of the most striking instances is that of Ancon or otter sheep, the ancestor of which was a long bodied, crooked-legged freak which was bred to sheep of normal character. Only the in dividuals which resembled the aberrant parent were used for subsequent breeding. With do mesticated plants the practice of breeding from the sports is still more striking, because it can be practised either sexually or asexually. The initial sport may appear as a seedling or as a ((bud-variation.* In the former case the gar dener usually progagates by means of seed, rigorously discarding all specimens that depart unfavorably from the apparent intent of the primal sport, and carefully saving those speci mens that approximate or accentuate the acters. If the sport is a bud-variation the gardener usually propagates it by means of i cuttings, practising a careful suppression of n dividuals which seem to retrogress and select ing desirable ones for further propagation, as in the former case. It may seem expedient to practise asexual methods with a plant pro duced sexually or vice-versa; in each case, however, the after-selection is imperative. Some bud-varieties fail to "come true" even from cuttings, and failure in this respect is common among seed sports. Bud-variation and seed-variation are the same kind since the same means of improvement can be used in each case.