CCXXviii PROCEEDINGS OF THE ROYAL HORTICULTURAL SOCIETY. 



and had been clamped, but not until after they had been some time 

 in the clamp had the trouble become evident. Nothing had been 

 seen of disease while the plants were growing. The tubers were sent 

 to Wisley for further examination, along with others from Hampshire. 



Pelargonium hybrids. — Mr. J. Fraser, F.L.S., showed further dried 

 specimens from the Wisley collection, and made remarks on their origin 

 from Pelargonium denliculatum, which appears to vary considerably 

 in the foliage. 



Seedlings from variegated plants. — Professor Bateson exhibited 

 leaves of Pelargonium illustrating the two types of leaf-variegation, 

 the mode of inheritance of which has been elucidated by Baur's classic 

 investigations. In the Pelargonium the nature of the sub-epidermal layer 

 — which layer gives rise to the germ-cells — determines the variegation or 

 non-variegation of the leaves of the offspring. If the sub-epidermal layer 

 contain chlorophyll, the offspring produced by self-fertilizing a varie- 

 gated Pelargonium have normal green leaves ; if, on the other hand, 

 the sub-epidermal layer lack chlorophyll, the plant on self-fertilization 

 gives rise to albino seedlings. Professor Bateson's experiments with 

 variegated forms of Chlorophytum elatum and C. comosum have led to 

 new and striking results. Chlorophytum elatum has leaves the 

 margins of which are white and the central parts green. Self-fertiliza- 

 tion of this type of variegated Chlorophytum results in the production 

 of seedlings with normal green leaves. In Chlorophytum comosum, 

 on the other hand, the variegation is reversed. A white stripe runs 

 down the middle of the leaf and the margins are green. The few 

 seedlings which have been obtained by self-fertilizing C. comosum of 

 this form of variegation are all albinos. Some conversation took 

 place with regard to the meaning of the phenomenon exhibited by 

 the Chlorophytum. Other examples in which albino seedlings were 

 produced were mentioned, and analogous cases of variegation were 

 referred to. It would be interesting to cross the white-edged form of 

 C. elatum with a form having a median white stripe to the leaf if such 

 is at present in existence. One was known at one time under the name 

 of medio-pictum, but appears to be rare if not extinct. The Com- 

 mittee would be glad to hear of its occurrence. It may be noted that 

 the white-edged Chlorophytum has no chlorophyll-less sub-epidermal 

 layer. 



Evolution of the Winter-flowering Begonia. — Sir Harry Veitch 

 showed a series of Winter-flowering Begonias to illustrate the evolution 

 of these useful and beautiful plants from the original forms. Begonia 

 socoirana, a species discovered in Socotra by Prof. I. Bayley Balfour, 

 and brought to England by him under some difficulties owing to the 

 Phylloxera orders in existence on the Continent, was crossed with one 

 of the tuberous forms, which had been retarded for the purpose, by Mr. 

 John Heal. B. socoirana, which was shown (fig. 198), flowers normally 

 at this season, and it imparted this character to the seedling of the 

 cross. The first of these was ' John Heal,' a very floriferous variety with 

 rather small flowers. This was crossed again with tuberous forms, and 



