MICROSCOPE IN THE GARDEN. 33 



In figures 44 and 46 tliey are represented from 

 the wheat and the aloe. In the latter plant the 

 cells of the cuticle are very much thickened. 

 They can also be seen on the cuticle of the fruit, 

 as shown from the holly in figure 241, plate 8, 

 and also on the organs and petals. These form a 

 beautiful object under the Microscope. The petal 

 of the common scarlet geranium {Pelargonium) 

 affords a beautiful instance of the way in which 

 the cells of plants become marked, by their pecu- 

 liar method of growth. This is illustrated in the 

 cells of the common red-flowered geranium at 

 figure 45, in plate 2. 



The vascular tissue of plants is either plain or 

 marked in its interior. If we examine the ribs of 

 leaves, the green stems of plants, or a longitudinal 

 section of wood, elongated fibres, lying side by side, 

 are observed, as is seen in the case of the elder, at 

 figure 53, plate 2. This is what is called " lig- 

 neous" or "woody" tissue, and the greater part 

 of the w^ood and solid parts of plants are com- 

 posed of this tissue. Such tissue is seen upon 

 the shoots of the young v^ine in figure 249, 

 plate 8. The fibres mostly lie in bundles, and are 

 divided from each other by cellular tissue. This 

 latter, in the woody stems of trees, constitutes the 

 " medullary rays," which are seen in transverse 

 sections of stems, extending from the pith to the 

 bark. The difference observable in the distribution 

 of the woody fibres and the medullary rays renders 

 the examination of transverse sections of the stems 

 of plants a subject ot much interest ; figure 54 

 and the following figures in plate 3, present the 

 appearances of thin sections of various kinds of 

 wood (figures 54, 55, 5Q, 51, plate 3). In the 

 transverse sections of stems of most plants, 

 large open tubes are observed. This is seen la 



