OF CONFERV.E. 



141 



in which the reproductive process is confined to one part of the 

 organism ; that is, certain regions are specialized and devoted to a 

 different office from that of the other merely vegetative portions, 

 and by this specialization a reproductive organ is produced. 

 Commonly, this organ is the terminal cell of the plant among the 

 lower grades of sea-weeds and their fresh-water relatives. The 

 one which I have represented here, (fig. 83, A,) in 

 its natural size, grows like a white mould over 

 dead flies and other insects which may happen 

 to fall in the water. You may very readily raise 

 it in a few days by throwing 

 some flies into a jar of water, 

 and letting it stand quiet in a n z\ 

 warm place, w r hen a white film 



F\ 



of fine threads gradually makes 

 its appearance all over the de- 

 caying body of the insect. These 

 threads, if examined soon after they become clear- 

 ly visible, will be found to be mere tubes with a 

 sharp point at the free "end. and a broad base 



where attached. After a while their tips lose their 



IA 



transparency and become whitish. If now they 

 are examined, it will be found that this part of 

 the plant is partitioned off from the rest, as in this figure, (fig. 

 83, B,) and the contents are little yellowish, globular bodies 

 crowded together as close as they can lie. Presently this whole 

 mass begins to be agitated, and the globular bodies tremble 

 from an apparently invisible cause, reminding one of a commu- 



Fig. 83. Saprolegnaferax? A, a group of plants growing on a dead fly; 

 B, the tip of a plant magnified 250 diameters ; a, its terminal aperture ; s, zo- 

 ospores ; C, zobspores just escaped from the plant. Original. 



Fif. 84. Saprolegna ferax ? Same as fig. 83. Various stages of growth 

 after the escape of the zobspores; A, a ripe zobspore; n 1 , its body; /, its vi- 

 bratory lash. B, the first stage of the plant-growth; n, its nucleus. C, sec- 

 ond stage ; n 2 , its nucleus. D, the young plant just attaching itself; p, the 

 basal end. 500 diam. Original. 



Fig. 83. 



