Plate IX. Electron micrographs of flagella and haptoneniata 

 from algae. 



(a) The cell body and the bases of the two flagella of a 

 spermatozoid of Fucus serratiis. The anterior flagellum (on the 

 right) carries two rows of mastigonemes, while the posterior 

 flagellum is bare. The two flagella diverge from their bases 

 near the anterior end of the cell, and the posterior flagellum 

 returns to the cell surface near the middle of the body where it 

 adheres to the surface of the eyespot. From the region of the 

 flagellar bases the fibrils that make up the " proboscis " run out 

 to form a flat loop at the anterior end. From Manton and 

 Clarke (1951). - 15,000. 



(b) The distal end of the anterior flagellum of Himanthalia. 

 The two rows of mastigonemes which occur on the main part 

 of the flagellar shaft are absent beyond the large spine, x 7,500. 



(c) The tip of a dismembered anterior flagellum of Himan- 

 thalia. Eleven fibrils can be distinguished, one of which carries 

 a large spine. Mastigonemes can also be seen, but their 

 relationship to the fibrils is uncertain. : 5,500. 



(6) and {c) are from Manton, Clarke and Greenwood (1953). 



{d) A whole cell of Chrysochromidina strobilus showing the two 

 flagella and the long coiled haptonema. ;: 1,800. 



(e) Transverse section of a haptonema of C. strobilus showmg 

 the six internal fibrils surrounded by three concentric mem- 

 branes. >: 92,000. 



(d) and (e) are from Parke, Manton and Clarke (1959). 



