The mutation theory; experiments and observations on the origin of species in the vegetable kingdom . ndiflova, and as I shalldescribe later in greater detail in the case of Celosia cris-tata. (See Part II of this volume.) In conclusion, we see that in nature as well as incultivation (especially in the case of horticultural vari-eties and other anomalies) intermediate forms betweenthe original species and its constant variety are oftenmet With. The two commonest are the half race and themiddle race or eversporting variety. The former hasa half curve, the latter a bilateral one. Both occur in ^
The mutation theory; experiments and observations on the origin of species in the vegetable kingdom . ndiflova, and as I shalldescribe later in greater detail in the case of Celosia cris-tata. (See Part II of this volume.) In conclusion, we see that in nature as well as incultivation (especially in the case of horticultural vari-eties and other anomalies) intermediate forms betweenthe original species and its constant variety are oftenmet With. The two commonest are the half race and themiddle race or eversporting variety. The former hasa half curve, the latter a bilateral one. Both occur in ^Vol. T, Part I, § 14, p. 122. 36 Latent and Scuii-Latcnt Characters. numerous species and genera, either together, or sepa-rately. Both are easily influenced by high nutrition andselection, hut are usually quite distinct and only appar-ently connected by transitional forms. § 5. TRIFOLIUM PRATENSE QUINQUEFOLIUM, AN EVER-SPORTING RACE. Four-leaved clovers are notoriously rare in nature,but it is perfectly easy to have many hundreds of them,provided a hereditary race can be obtained. Isolated ex-. Fig. 3. Trifolium pratensc quinqiicfolhini, five-leaved andseven-leaved leaves of clover. The left leaf, A, showsa transition towards the 6-merous leaf in the splitting ofone of its leaflets. amples of this race seem to occur sporadically in nature;all that has to be done is to find, to isolate, and to multiplythem. (Fig. 3.) In the following section I shall describe the historyof a particular race. I shall do so largely with a view toemphasizing the contrast between a middle race and a Trifolhmi Pratensc Quiiiqucfoliiim. 37 half race. In a half race the latent or semi-latent characteris very seldom visible, perhaps in one leaf or on one plantamongst many thousands, and after several years of se-lection it is only on isolated individuals that two or threespecimens of the anomaly may be found. In the middle race, or eversporting variety as I callit in contradistinction to the half race
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