SCIENTIFIC COMMITTEE, OCTOBER 15. 



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Bud on Cotyledon. — Mr. Chittenden also showed a seedling of 

 Bryophyllum sp. having a small shoot bearing two leaves growing 

 from the petiole of the cotyledons, and another in the notch of the 

 apex of the same cotyledon, being produced in much the same way 

 as buds are in the angles of the crenations of the ordinary leaves. 



Scientific Committee, October 15, 1907. 



Mr. E. A. Bowles, M.A., F.L.S., in the Chair, with twelve members 

 present and numerous visitors. 



The Up-country Tea-root Disease of Ceylon. — Dr. C. B. Plowright 

 sent specimens of bark and roots of tea plants, illustrating the following 

 note : " Mr. T. Petch, the Government mycologist of Ceylon, sends 

 specimens of this disease. It is due to Polyporus hypolateritia of 

 Berkeley, a species which is now allocated to the genus Poria. It 

 is most prevalent above 4,000 feet, and is easily distinguished from the 

 disease caused by Bosellinia. If a dying bush be uprooted, the roots 

 are seen to be covered with small white raised patches or knobs of 

 mycelium about one- twelfth of an inch in diameter with reddish raised 

 margins. From these nodules a mycelium spreads to other roots, white 

 at first, but subsequently forming a thick cord with a tough red coat, 

 while the mycelium between the bark and the wood forms a thin con- 

 tinuous white sheet. The fructification (the Poria) is generally formed 

 on the stem just above the ground, but it may be formed on the surface 

 of the soil. In one experimental culture it was produced on the under 

 side of a flower-pot, an illustration of the travelling power of the fungus. 

 The fungus is white with a red edge and under-surface ; hence the specific 

 name which was given by Berkeley to specimens from India. Its life- 

 history as a parasite has been worked out by Mr. Petch." 



Hybrid Orchids. — Mr. F. W. Moore, V.M.H., made some interesting 

 remarks upon two hybrid Orchids sent by Mr. H. J. Chapman. The first 

 was the result of intercrossing the two albinos Cattleya intermedia alba 

 and C. Schrdderae alba. The flowers of the cross had the three sepals 

 and two of the petals with a rosy tinge, while the lip was at the edges 

 of the basal portion a little deeper in colour, and had the terminal portion 

 magenta with a stripe of the same colour running towards the throat, the 

 only portion of the flower that was pure white being the inner part of the 

 throat on each side of this stripe. The colour, therefore, showed reversion 

 to the typical form ; the shape, however, of the flowers showed traces of 

 both parents. , The second flower was the result of a cross between the 

 so-called albino forms, Cypripedium insigne Sander ae and C. callosum 

 Sanderae. This, like the first, showed distinct traces of the coloration 

 of the typical forms of both parent species, thus again reverting. These 

 two specimens seem to illustrate in another group of plants that 

 phenomenon which has been pointed out by the Mendelian workers 

 with Sweet Peas, where the colour-producing factors that were present 

 separately in the two parents, so that they were albinos, meet in the 

 offspring and produce colour. As Mr. Moore pointed out, not all albino 

 Orchids when crossed produced coloured flowers, but albinos may be 



