124 BtTLBIIiS AND GEMMiE. 



But perhaps the most pertinent evidence of the sympathy 

 which prevails between bulbils and flowers is furnished by the 

 Lily tribe. Most amateur gardeners may know that the quaint 

 old Tiger-lily, a favourite with our grand-parents, propagates 

 itself by bulbils, and produces seed but rarely; but to what 

 extent the presence of the one is connected with the absence of 

 the other may not be equally apparent. Evidence is not wanting 

 that the old-time ancestors of this lily,bore perfect hermaphrodite 

 flowers, and that the repeated demands of certain conditions of 

 environment have eventuated in the abortion of the pistil in 

 some flowers, and of the stamens in others, the result being that 

 pollen has to be transported from the stamens of one flower to 

 the pistil of another in order to bring about a fertilization of the 

 ovary. Now, if the pollen ripened simultaneously with the 

 attainment of functional activity by the pistil, and its transit to 

 the pistilliferous flower were guaranteed, fertilization would be 

 insured and seed would follow. But, knowing as we do, that a 

 rise or fall of temperature, the absence or presence of certain 

 elements in the soil, and a high or low vitality at the critical 

 time of flowering may ripen the stamens and pistil at periods 

 sufficiently removed to preclude fertilization, we can easily see 

 that the production of seed is a very uncertain affair, and that, 

 oftener than not, none will be formed at all. Considering this, 

 need we ask for weightier reasons for the presence of such purely 

 vegetative organs of reproduction as bulbils ? 



This same Lily -tribe has other excellent examples of bulbil- 

 bearing plants. The genus Allium alone, which, by the way, 

 furnishes us with such useful culinary herbs as the onion and 

 leek, contains no fewer than five. What in these instances most 

 forcibly strikes the student is that, unlike the foregoing plants, 

 the bulbils in these several cases appear at the extremity of the 

 flower stalk among the flowers, if there are any, which, however, 

 is not always the case. If there are bulbils the flowers are fewer 

 pro rata, and again and again does it happen that the entire 

 umbel of flowers is replaced by a head of bulbils. More cogent 

 evidence than this in support of Charles Letourneau's dictum, 

 — "The faculty of reproduction. . . .is only a simple extension of 

 the nutritive property,"*— it were difficult to find. Elsewhere the 

 * Biology, p. 30. 



