502 Botanical Society of Edinburgh. 



fructification in order to avoid picking the one for the other. At the 

 head of Glen Dole, and above the path called Jock's Road, both ferns 

 grew luxuriantly. Polypodiiim alpestre descends much lower than 

 has been supposed. It was found at little more than 50 feet above 

 the Dole, on the bank below the Astragalus alpinus cliff. 



Mr. G. Lawson remarked that a statement similar to that of Mr. 

 Croall had been made to him last summer, and he was thus led to 

 pay particular attention to the point when he visited Clova as one of 

 Professor Balfour's party. The statement is not correct, the Athy- 

 rium being a frequent associate of Polypodium alpestre. This cir- 

 cumstance, together with the variability of both plants (whose re- 

 spective varieties are in some cases very similar to each other), ren- 

 dered it often difficult to distinguish the one from the" other, without 

 inspecting the sori. 



Mr. G. Lawson exhibited under the microscope preparations of 

 the colouring-matters of the flower of Strelitzia ReyincB, and draw- 

 ings of the same. This plant is interesting as presenting examples 

 of both the xanthic and cyanic series in the same flower, but still 

 more remarkable in the microscopical peculiarities of its colouring- 

 matters, which are referred to by Mohl in the "Vegetable Cell" 

 (p. 44). Mr. Lawson stated that in the blue (or purplish-blue) part 

 of the flower, the colouring-matter entirely consists of spherical gra- 

 nules of an intense blue or bluish-purple colour, with occasionally 

 cells containing similar shaped granules of bright crimson. All the 

 granules of any one cell appear to be constantly of the same colour. 

 In the yellow part of the flower, the colouring-matter appears in a 

 very different form. Instead of spherical granules, we have slender 

 filaments, which are more or less spirally twisted and rolled up in 

 various ways in the cell, resembling in their twisting the more delicate 

 spiral fibres in the external cells of the roots of Epiphytal orchids ; 

 but they are in many cases short, and form small round coils, giving 

 the outline of globular bodies, which likewise, however, occasionally 

 occur. "While red and blue colouring-matters usually occur in the 

 vegetable kingdom diffused in the cell-sap, we find them both in 

 Strelitzia in a globular form. Although deceptive appearances often 

 presented themselves, Mr. Lawson felt inclined to believe, from the 

 examination of numerous specimens, that diffused colour did not at all 

 occur in the flowers of Strelitzia. When the flower has attained its 

 maturity, the cells are often so completely filled with the deep blue 

 granules, that they appear as a dense mass of blue, apparently homo- 

 geneous, matter in the interior of the cell. The flower should there- 

 fore be examined in the young state, not only before it has expanded, 

 but long before the spathe has opened to expose it to the action of 

 the light ; even then the colouring of the flower will be found to 

 have far advanced, but the cells are not then so completely filled with 

 the blue globular granules as to disguise their character, and are 

 distinctly seen. The cells containing the yellow filaments are gene- 

 rally of larger size and more elongated in form than those containing 

 blue or red globules. 



