117 



single specimen at St, George, Utah. In addition to my former note, 

 I have to add that I have since discovered several fruiting speci- 

 mens of Tricardia at Hawthorne and Candelaria, Nevada. The plant 

 occurs sparingly along the eastern base of the vSierras, from Reno to 

 the southern boundary of Nevada. 



Salt Lake City, July 24. Marcus E. 



J 



V 



Botanical Notes. — The Colors of Flo7vers.—^ln an interesting ar- 

 ticle by Grant Allen, in Nature^ on ' The Colors of Flowers, as illus- 

 trated by the British Flora/ the author says : 



The different hues assumed by petals are all, as it were, laid up 

 beforehand in the tissues of the plant, ready to be brought out at a 

 moment's notice. And all flowers, as we know, easilysport a little in 

 colon But the question is, do their changes tend to follow any regular 

 and definite order ? Is there any reason to believe that the modifi- 

 cation runs from any one color towards any other ? Apparently, 

 there is. All flowers, it would seem, were in their earliest iorm yel- 

 low; then some of them became white; after that, a few of them 

 grew to be red or purple; and, finally, a comparatively small number 

 acquired various shades of lilac, mauve, violet, or blue. 



§ome hints of a progressive law in the direction of a color- 

 change from yellow to blue are sometimes afforded us even by the 

 successive stages of a single flower. For example, one of our com- 

 mon little English forget-me-not^, Myosotis versicolor^ is pale yellow 

 when it first opens ; but as it grows older, it becomes faintly pinkish, 

 and ends by being blue like the others of its race. Now, this sort 

 of color-change is by no means uncommon; and in almost all known 

 cases it is always in the same direction, from yellow or white, 

 through pink, orange, or red, to purple or blue. Thus, one of the 

 wall-flowers, Cheiranthus chamaeleo, has at first a whitish flower, then 

 a citron-yellow, and finally emerges into red or violet. The petals 

 of Stylidiuni fruticosu??i are pale yellow to begin with, and after- 

 wards become light rose-colored. An evening primrose, Oenothera 

 tetraptera^ has white flowers in its first stage, and red ones ^t a later 

 period of development. Cobaea scande/is goes from white to violet ; 

 liibiscMS mutabUis from white through flesh-colored, to red. The 

 common Virginia stock of our gardens {^Malcolmia) often opens of 

 a pale yellowish green; then becomes faintly pink ; afterwards deep- 

 ens into bright red, and fades away at last into mauve or blue. 

 Fritz Miiller noticed in South America a Lantana^ which is yellow 

 on its first day, orange on the second, and purple on the third. The 

 whole family of Bojaginaceae begin by being pink, and end by being 

 blue. In all these and many other cases the general direction of 

 the changes is the same. They are usually set down as due to 

 varying degrees of oxidation in the pigmentary matter. 



If this be so, there is a good reason why bees should be specially 

 fond of blue, and why blue flowers should be specially adapted for 

 fertilization by their aid. For bees and butterflies are the most 

 highly adapted of all insects to honey-seeking and flower-feeding. 

 They have themselves on their side undergone the largest amount of 

 specialization for that particular function. And if the more special- 



