THE ALG^E. 109 



these on each antheridium. Each of these circles is the 

 outer end of a cylindrical cell which extends inward 

 towards the center. These eight cylindrical cells are the 

 manubria or handles. Draw an antheridium, taking pains 

 to represent clearly the circular cells and the polygonal 

 cells which surround them. 



By pressure on the cover glass crush an antheridium. 

 Find a manubrium. (Fig. 60, D.) On its inner end 

 notice an irregularly spherical cell, the capitulum ; smaller 

 spherical cells, the secondary capiiula, project inward from 

 the capitulum, and from each of these grow long filaments 

 composed of minute cells. (Fig. 60, (7.) Each of these 

 cells produces an antherozoid (Fig 60, .F), a motile cell 

 which bears two long flagella at its anterior pointed 

 end. Each antheridium bears between 20,000 and 40,000 

 of these antherozoids. If the antheridium is of the right 

 degree of maturity, the antherozoids can be seen in the 

 cells of the filaments, or swimming about free in the 

 water. Find them if possible. Stain with iodine after 

 they are found, to bring their very delicate transparent 

 flagella into view. Under the cover of another mount 

 run a very little gentian violet and look for the anthero- 

 zoids in the cells of the filaments. This treatment will 

 also frequently show the divided nuclei in cells near the 

 ends of the filaments that are undergoing division. Draw 

 all that you have seen. 



9. Study the archegonium. This also may be recog- 

 nized by the naked eye or magnifying glass as an ovoid 

 brown, green, or black body situated in the axils of the 

 leaflets or bracts. (Fig. 60, A.) Find archegonia in dif- 

 ferent stages of development. Under high power notice 

 the spiral cells that envelop the egg cell. Focus below 

 the spiral cells on a young archegonium and make out all 

 you can of the egg cell. Notice the crown of cells at the 

 apex of the archegonium. If possible, examine the crown 



