MICROSCOPIC OBJECTS. 20 



Fig. 39. Petal of Fritillary (Fritillaria meleagris) , x 120. 



The petal of this flower is rather remarkable for the irre- 

 gular formation of the cells of the cuticle, which will be 

 remarked on looking at the drawing. The flower is named 

 from the Jj&tmfritillus, a dice-box, the coloured markings on 

 the petals slightly resembling the board upon which dice are 

 thrown. 



The petal, or rather the cuticle of the petal, of this flower 

 shows best when mounted dry. 



Fig. 40. Pollen of Convolvulus (Convolvulus sepium), x 200. 



The drawing illustrates the spherical form of pollen, men- 

 tioned at p. 21 (fig. 42). Many of the spherical pollens have 

 spiny processes proceeding from the outer cuticle as the pollen 

 of the Mallow, the Hollyhock, &c. A great many are also 

 furnished with ridges, as in the above drawing. Other ex- 

 amples may be found in the pollens of the Dandelion, Cobaa 

 scandens, &c. 



Before mounting pollens in fluids, they should be placed in 

 a solution of gum or sugar, as this tends to mitigate the 

 endosmotic action. 



In the case of this pollen, it is best when mounted in a 

 dry opaque cell. 



