DESCRIPTION OF THE PLATE. 



Ail the figures were drawn with the help of Zeiss's caméra lucida, the paper 

 being placed on the table, and inclined at an angle of 20 . Except for figs. 1 and 

 13 Leitz's 1/12 oil immersion objective ivas used with Zeiss's N° 4 ocular. For 

 figs. 1 and 13 Leitz's 1/12 oil immersion objective with Zeiss's ocular N° 2 iras 

 employed. 



LIST OF ABBREVIATIONS. 



a. — cell showing sénescence. 



b. — withered cell. 



c. — burst cell. 

 pr. — protoplasm. 



n. — nucleus. 



ni. — nucleolus. 



e. — endonucleolus. 



v. — vacuole, 



nv . — ■ nuclear vacuole, 



cr. — crystalloid. 



crk. — granular crystalloids. 



FIG. 1. From young ovary, 3 millemetres in length. Hair cell, a, at 

 the stage when it is first distinguishable from other epidermal 

 cells. 

 FIGS. 2-3. Hairs from ovary 5 millemetres 'long. No erythrophilous bodies 

 outside the nucleus. 



Fig. 2 shows 4 nucleoli in the nucleus. 



Fig. 3 exhibits characteristic dumb-bell shaped nucleus, containing 

 3 nucleoli. 

 FIGS. 4-5. From an ovary 7 millemetres in length. 



Fig. 4 is a very typical hair cell of this stage with numerous 

 small erythrophilous granules in the cytoplasm, crk. 

 Fig. 5 shows slender crystalloids, cr, as well as granules, crk. 

 FIGS. 6-10. Mature hair cells from the ovary of an opening flower. 



Fig. 6. The nucleus lias a peculiar, almost pear-shaped outline : 



9 small crystalloids are seen in the cytoplasm. 



Fig. 7 shows a group of large and small elongated crystalloids. 



