274 EXPLANATION OF THE PLATES. 



Fig. 7. Ciliated zoospore or motile gemma of (Edogonium 

 vesicatum. 



Fig. 8. The same in germination. Having lost its crown of 

 cilia, it has begun to emit radical filaments from its base (p. 32). 

 (Both from Thuret). 



Figs 9 and 10 (from Thwaites and Berkeley), illustrate repro- 

 duction by androspores, or minute phytoids, formed by the ger- 

 mination of a kind of zoospores, and consisting of a pedicle and 

 two antheridial cells, containing each a single antherozoid. 

 In Fig 9, a filament of (Edogonium is shown, with several an 

 drospores, and in Fig. 10, a similar body is seen attached to a 

 spore cell of Bulbochcete crassa (p. 33). 



Fig. 11. Reproduction in Vaucheria (from Pringsheim) ; a, 

 the " hornlet," or antheridium ; 6, the sporangium, both at 

 first diverticula of the general cavity of the filament, but after- 

 ward shut off so as to form distinct cells ; c, micropyle or ter- 

 minal pore in the sporangium, by which the antherozoids gain 

 access, when liberated by the dehiscence of the point of the horn- 

 let. The germinal body is at first covered only by a layer of 

 mucus, penetrable by the spermatic particles, but after impreg- 

 nation, this becomes consolidated into the proper coat of the 

 spore (p. 34). 



Fig. 12. Reproductive organs of SporochnusAdriaticus (from 

 Kutzing), illustrating the arrangement in the higher Algse. a, 

 antheridial filament ; 6, sporangium. These parts are more 

 generally separated, and are frequently situated on different 

 plants (p. 36). 



Fig. 13. Antherozoid of Fucus vesiculosus (from Thuret) 

 (P- 32.) 



Fig. 14. (from Berkeley). Part of the hymenium of Agaricus 

 velutinus, illustrating the acrogenous fructification of the higher 

 Fungi, ct, basidium, with four stalked spores on its summit 

 (p. 42-45). 



Fig. 15. (after Currey). Compound spore of Phragmidium 

 bulbosum in germination, showing the production of threads of 

 mycelium from each of the compartments into which it has be- 

 come divided, and the secondary spores formed on these fila- 

 ments in the acrogenous way (p. 44). 



