8o 



KE8EAKCHES ON FUNGI 



In still air, spores, after leaving the hymenial 

 surfaces, fall vertically downAvards at the rate of 

 aliout 1-5 jiiiii. per second.^ If, therefore, one 

 takes the precaution to eliminate small convec- 

 tion currents by covering the pilei placed on 

 paper ^vith small glass vessels, one can produce 

 a spore print of the gills or hymenial tubes, &c. 

 Such spore prints are shown in Figs, ol and 

 33. In the first one the white spores of Lepiota 

 vdckodes were collected on black paper, whilst in 

 the second the black spores of Anellaria separ- 

 ata were collected on Avhite paper. The radiating 

 spore lines correspond to spaces between the gills. 



The rate of accumulation of a spore-deposit 

 depends on various factors, such as the fungus 

 species, age of the pileus, temperature, &c. How- 

 ever, one may often obtain a recognisable spore 

 print in the short space of fifteen minutes 

 (Fig. 33, A). As the spores fall continuously, 

 usually for days together, the deposits become 

 denser and denser as time goes on (Fig. 33, B 

 and C). By moving a pileus from one place to 

 another every hour and thus procuring successive 

 spore prints, one may readily convince oneself of 

 the continuity and regularity of spore-emission. 



When a pileus is raised above the paper and 

 spore-deposition takes place under a beaker or 

 relatively large glass vessel, the spore-deposit no 

 longer gives a print of the gills but has a cloudy 

 appearance (Fig. 34, A). The reason for this is 

 that the air, through which the spores fall, is not 

 perfectly still but is undergoing slow convection 

 movements. The spores, therefore, are unable 

 to fall quite vertically. In Fig. 34, A, is shown 

 KiG. S2. — Anellaria sejxt- a cicposit froiii a pilcus of Ancllaria separata 



rata. After reiiiov;il of . 



the stiju-s. pilei of fniii- raiscd 2 ciu. abovc the paper. I he accumu- 



liodifs of tliis s])ccics 



were used for ol.tiiinini.' , ^,., . . „, .... -.^-^^t 



the si)oro-'leiiosits shown ^ Vide infra, (Jhaps. A\ . and X\ 1. 



in Kiys. 3:i;iii(l m. Ahout 



natural size. 



