CHAPTER VII. 



VEGETABLE STRUCTURE VITAL AND CHEMICAL CHARACTERISTICS THE 



VEGETABLE CELL FUNGI ALGJ2 MOSSES VOLVOX DESMIDACEvE 



-STRUCTURE OF PLANTS FUNGOID DISEASES ADULTERATION OF 



ARTICLES USED FOR FOOD PREPARATION FOR MICROSCOPIC EXAMI- 

 NATION CUTTING SECTIONS WARINGTON's MICROSCOPE MAGNIFY- 

 ING POWER OF THE EYE CONCLUSION.* 



INGE fhe introduction of the achromatic micro- 



scope, we have obtained nearly the whole of the 

 valuable information which we now possess re- 

 lative to the minute structure of vegetables. 

 Before that time, although some progress had 

 been made in vegetable physiology, yet the 

 means of distinguishing one structure from an- 

 other, with their several external characters, 

 comprehended the amount of our botanical know- 

 ledge. " The vegetation which every where 

 adorns the surface of the globe, from the moss 

 that covers the weather-worn stone, to the cedar 

 that crowns the mountain, is replete with mat- 

 ter for reflection. Not a tree that lifts its 

 branches aloft, not a flower or leaf that expands 

 beneath the sunlight, but has something of ha- 

 bit, of structure, or of form, to arrest the atten- 



* DESCRIPTION OF PLATE XV. DESMIDACE.E, AFTER RALFS. 



Euastrum oblongum 

 Micrasterias rotata 



,, denticu] 

 Desmidium quadran: 

 Didymoprium Grevillii 



' Borreri 

 Sphserozosma vertebratum 



Staurastrum, tumidum 

 dilat 



hirsu 



Cosmarium Ralfsii 



Closteria 



