MICROSCOPIC OBJECTS. 



Fig. 41. Pollen of Hyacinth (Hyacinthus orientalis), x350. 



This drawing illustrates the elliptical form of pollen, men- 

 tioned below (fig. 42). The granular protoplasm, which, in 

 the case of pollens, is called the fovilla, appears to be of a less 

 dense character than in most of the elliptical pollens, and is 

 therefore not so much affected by endosmosis on the applica- 

 tion of fluids. The skin or cuticle also appears to be tolerably 

 thick. It will therefore be advisable to mount this pollen 

 in fluid. The colour of the pollen is yellow. 



Fig. 42. Pollen of the Evening Primrose (CEnothera 

 biennis), x 120. 



This form of pollen is rather uncommon, the general forms 

 being chiefly spherical, elliptical, &c. In some plants, as in 

 the Orchids, the pollen coheres in waxy masses. The remark- 

 able characters and forms of the ridges, furrows, &c. which 

 appear on most pollens, seem to be caused chiefly by the 

 contractions of the outer skin or cuticle ; these contractions 

 may often be noticed to have disappeared on the application 

 of liquids, such as water &c. Hence it is advisable to mount 

 pollens, when sufficiently transparent, dry, as the best way 

 to retain their natural forms. 



