1897] NOTES AND COMMENTS 13 
its brilliant golden hue to a pigment called carotin (from its presence 
in the carrot root), “ which is amassed in discoidal bodies that nearly 
fill up the cells of the epidermis, especially towards the base 
of the petal; in other parts, especially when the flower is fully 
expanded, it seems diffused in oily droplets or amorphous granules.” 
In either case the starch grains in the subjacent tissue act as a 
reflector, and contribute greatly to enhance the effect. The flower- 
heads contain a considerable amount of sugar, starch, calcium oxalate, 
and soluble phosphates, in these respects approaching more to the 
character of leaves than is usual. The stem and root of this butter- 
cup (Ranunculus bulbosus) are remarkable for the presence of an 
acrid camphoraceous body easily decomposed into a volatile bitter 
principle (anemonin) and an acid, even during the drying of the 
plant, so that its original poisonous character disappears. 
Bird’s-foot trefoil (Lotus corniculatus), with the brilliant orange 
and crimson tints of its little papilionaceous flowers, is known to 
everyone. To produce this vividness and lustre the epidermal cells 
are swollen into papillae, and contain no less than three distinct pig- 
ments. There are the solid carotin corpuscles, and also two colour- 
ing-matters in solution in the cell-sap. One is a clear, yellow juice, 
the other is identical with the anthocyan of the rose. Where the ~ 
latter predominates we get the deep red colour. 
The tiny flowers of the cheerful little yellow bedstraw (Galiwm 
verum) contain carotin, much yellow resinous matter, and “a curious 
purplish substance (possibly purpurin) insoluble in cold alcohol or 
benzene after purification.” The flowers also contain a species of 
ferment which, like rennet, has the power of coagulating boiling 
milk. A substance known as rubichloric acid is present, not only in 
the flowers but in the stem and root. It forms.a colourless solution 
in water, but when boiled with a few drops of hydrochloric acid, 
suddenly produces a deep blue, then a green colour, and deposits a 
dense, dark green precipitate soluble in ammonia. The disc florets 
of the daisy are tinged with carotin granules; the crimson of the 
ray florets is due to a soluble pigment described as a tannin anhy- 
dride. The blue of the harebell and chicory is again a tannin 
derivative. 
Two colouring matters are engaged in the decoration of the 
primrose. At the base of the petal-limbs, where the tint is more 
deeply orange, carotin granules are present; the rest of the corolla 
contains a pale yellow, soluble pigment. Although the tints are 
comparatively feeble, chemical analysis shows that the plant is 
capable of “an infinitely richer wealth of coloration” than it shows 
in our climate, since “it seems almost impossible to exhaust the 
flower heads of substances which yield vivid and powerful orange 
and yellow dyes.” 
