76 



THE MICROSOOPIST. 



Seeds are generally opaque objects, and present a great 

 variety of beautiful and interesting forms. 



Hard Tissues, the stones and shells of nuts, &c., are pre- 

 pared like bone, &c., by cutting and grinding. Some require 

 the lapidary's wheel. 



Rapliides, or crystals from the interior of plants. If the 

 leaf or bulb of a common hyacinth be wounded, a discharge of 

 fluid ensues ; if this be received on a slide and submitted to 

 the microscope, a number of minute acicular bodies will be 

 observed floating in the liquid. They are called raphides. They 

 are common in many plants. Fig. 26, a. represents cells of 



Fig. 26. 



the beet-root, containing conglomerate raphides ; b, octohedral 

 and prismatic crystals of oxalate of lime in the cells of an 

 onion. By scraping hickory, or other bark, on to a slide, 

 moistening it with the breath, and blowing off the woody par- 

 ticles; or by placing a part of the ashes of a burnt maple leaf, 

 coat of an onion, &c., on a slide, such crystals may be seen. 

 They may be mounted dry or in balsam. 



Mosses are supposed to be destitute of woody fibre and vas- 

 cular tissue. When a leaf is carefully examined, the septa 



