But whether the [>ii>ment was actually brought to or 

 developed in the petals' cells, would really make but little 

 difference to the analogy, inasmuch as there would be an 

 actual movement of sap in either case. In our example 

 however not even this possibility was suggested. 



Mr. Bergen alludes to "the development of color in cells 

 of plants," a sul)ject not mentioned in my text, but in pass- 

 ing I will point out some resemblances in plant and animal 

 as to color. Cells, of course, and the develo})ment of color 

 in them, are not i)eculiarities of plants : the bodies of ani- 

 mals as well, are com[)()sed of cells, and even the i)lood 

 vessels are only lengthened cells. As pure and brilliant 

 colors are derived from red blood as from j^olorless saj). 

 These colors are more conniion among those lower animals 

 which in sim})licity of organization are nearer to the vege- 

 table. Many sjjecies of worms have colors of much beauty ; 

 the criisfacece are remarkable for the l)rilliancy of their 

 coloring ; reptiles are highly colored ; there are green frogs, 

 black and yellow salamanders, snakes and lizards of innu- 

 merable tints : "in insects the colors of the two stagi^s larval 

 and adult are often strongly contrasted, and such beauty of 

 pattern and design cannot be found in the tioral kingdom " : 

 birds and fishes have both structural and pigmental colors, 

 while mammals are rarely remarkable for brilliant pigments ; 

 the different races of man have quite a range of color, 

 white (?), red, brown, and black, and disease of the liver 

 may produce a yellow color, but the principal display of 

 color is contined to the hair and the visual organs, which 

 contain real pigments liable to change of tints as in flowers, 

 and the internal organs have various tints. These colors 

 are separated in the animals from the nourishing constitu- 

 ents of the blood, by dialysis, chemical action, and to some 

 extent by the effect of solar light closely similar to the de- 

 velopment of color in vegetable cells from the colorless sap. 

 Moreover some lipochromes identical in character are pro- 

 duced in the animal and the vegetal)le I 



