44 Macfarlane. — Dioncea Muscipula, Ellis. 



The relatively large number of leaves provided with more 

 than six hairs, that the writer has encountered, probably points 

 to a condition when the hairs were more diffuse in their 

 distribution; while the close similarity in development and 

 structure between the brown stellate leaf hairs and the 

 secreting glands, favors the view that the latter are merely 

 specialized examples of the former. 



EXPLANATION OF PLATE IV. 

 Illustrating Dr. J. M. Macfarlane' s paper on Dioncea. 



Fig. i. Surface view of lower part of sensitive hair, a, base of hair; 

 b, sensitive joint ; c, shaft. The cell wall surfaces of b exhibit minute pit 

 areas. X 400 . 



Fig. 2. Longitudinal median section of lower part of sensitive hair ; 

 X 400 . 



Fig. 3. Transverse section of hair at junction of base and joint cells ; 

 X 400 . 



Fig. 4. Outline surface view of secreting gland; X 400 . 



Fig. 5. «, b, c and d. Forms of hair from lower leaf surface ; X 400 . 



Fig. 6. Vertical section of gland parallel to secondary leaf bundles ; 

 X 400 . 



Fig. 7. Vertical section of gland at right angles to the last. 



Fig. 8. Surface view of epidermal cells, after slight treatment with 

 dilute sulphuric acid and eosin staining ; X "750. 



Fig. 9. Surface view of epidermal cells after iodine and sulphuric 

 solution treatment and eosin staining. The continuity of the intercellular 

 protoplasmic threads is traceable ; X 750 . 



Fig. 9a. Portion of swollen cell wall penetrated by intercellular pro- 

 toplasmic threads. The thickened areas in the three figures are rather 

 exaggerated in amount. 



