THE FLORAL WORLD AND GARDEN GUIDE. 311 



the forcing-house as wanted. The young growth must be inured to 

 the light in a gradual manner, and the plants kept near the glass. 

 After they are well started into growth, water liberally, and let them 

 have a breath of fresh air during the warmest part of the day ; but 

 it must be admitted without chilling the tender growth. 



The bulbs must not be left in the .plunge bed long enough for 

 the foliage to grow long and become blanched. Therefore, when 

 the flowers are not wanted until late in the spring, lift them out of 

 the plunging material and place them in a .cold frame or pit, where 

 light and air will have free access to them. Those for early flower- 

 ing must not be exposed to too great a heat, or the flower-spikes and 

 foliage will be drawn up weak and spindly ; and at all times keep as 

 close to the glass as possible, because neat, properly-developed 

 foliage that will maintain an erect position without support is nearly 

 of as much importance as good spikes of flowers, and will tell with 

 equal eflect in competitive groups. 



Do Plants absorb Moisture through thetr Leaves ? — Two French 

 botanists, Prillieux and Duchartre, have recently turned their attention to this 

 question, and their experiments lead to the conclusion that it must be answered, 

 contrary to the belief of all the older botanists, in the negative. M. Duchartre's 

 experiments were made for the most part on epiphytes, plants having no direct 

 communication with the soil, and which are yet found to contain potash, soda, 

 alumina, and other ingredients which plants whose roots grow in the earth derive 

 from that source. It these plants derive their sustenance from the moist vapour 

 by which they are surrounded, it is difficult to understand how they can procure 

 these materials. But if they absorb not aqueous vapour, but water itself, we can at 

 once account for the possession of these inorganic materials. To ascertain how 

 far this conclusion is just, M. Duchartre placed several of these epiphytes, provided 

 with their aerial roots, in closed vessels filled with muist vapour; the result was to 

 confirm the observation of Prillieux, that under these circumstances the plants lost 

 weight. If, however, from any cause the plants came into contact with liquid 

 water, it was absorbed readily, and the plants increased in weight. When leaves, 

 flaccid from undue evaporation, are suspended in moist air, they recover their fresh- 

 ness, though they do not gain in weight; hence the inference is drawn that the 

 renewed vitality of the leaves is due, not to the absorption of vapour, but to the 

 transference of fluid from one portion of the branch to another. When leaves, how- 

 ever, are actually plunged in liquid water for a considerable time, ttiey do absorb 

 it in considerable quantities. * 



Self-Fertilization a>d Cross-Fertilization of Plants. — Mr. A. W. Ben- 

 nett reports in the Journal of Botany for October a series of observations on this 

 subject. He states that there are now known to be three modes by which cross- 

 fertilization is especially favoured:: — the phenomena of dimorphism and trimorphism, 

 to which Mr. Darwin has called attention ; special contrivances for effecting the 

 transference of pollen by insects from one flower to another ; and the fact, which 

 has not yet received so much attention, that in the same flower the pistil and 

 stamens frequently arrive at maturity at different times. By observing a number of 

 British plants, he Iihs come to the conclusion that the most usual order is for the 

 stamens to ripen before the pistil (protandry) :: the simultaneous maturing of the 

 two organs (s\ naciue) is nearly equally common : while the ripening of the pistil 

 before the stamens (protogyny) is far more rare. Although protandry and protogyny 

 do not, in most cases, actually foibid the possibility of self-fertilization, they render 

 cross-fertilization far more likely. The most striking contrast was found to exist 

 between the common harebell (Campanula rotundifolia), in which the pollen is 

 discharged and the anthers wither up long before the stigmata are developed ; and 

 the Scrophularia aguatica, in which the pistil is mature very much earlier than the 

 stamens. 



