SCHIZOPHYLLUM COMMUNE 113 



3. The upper surface of the pileus is usually hairy or woolly. 

 A means is thus provided for the rapid absorption of water on 

 the advent of rain. Free water placed at one edge of the pileus 

 quickly passes by capillarity over the entire upper surface. Since 

 in many species the fruit-bodies more or less overlap one another, 

 this arrangement may be of advantage in hastening recovery after 

 desiccation. The hairs, like those on the leaves of certain xero- 

 phytic Phanerogams, are doubtless of some service in diminishing 

 the rate of transpiration in dry weather. Direct evidence of this 

 is afforded by an experiment made by Miss J. S. Bayliss,^ who 

 found that the removal of the hairs from the upper surface of a 

 pileus of Polystictus versicolor increased the rate at which the 

 process of drying took place. 



4. They are able to withstand prolonged and severe frost (such 

 as occurs at Winnipeg). 



5. They shed their spores at low temperatures. A number of 

 them can perform this function even at 0° C.^ 



6. Their attachment is unilateral. This is connected with the 

 fact that they grow on stumps, sticks, and fallen logs. The 

 dimidiate form of the fruit-bodies is as well adapted to the posi- 

 tion of the woody substratum as the radial form is to the position 

 of the earth in the Mushroom and Boleti, &c. 



The Genus Schizophyllum. — The genus Schizophyllum is unique 

 among the Agaricinete in that it is characterised by possessing 

 gills which are either partially or completely divided down their 

 median planes into two parts. We shall now proceed to interpret 

 this remarkable morphological fact in the light of observations made 

 upon Schizophyllum commune. 



Schizopliyllain coTnmune is a species comparatively rare in 

 England but extremely common in Manitoba, where it is found 

 on sticks, logs, and stumps. The fruit-bodies, which are usually 

 attached laterally, attain a width of about o cm. They occur 

 singly or, more frequently, in imbricated groups. Their general 

 appearance is shown in Fig. 41, A and B, and Fig. 42. The gills 

 are in distinct fasciculi, each pair of deeper and longer ones being 



^ Miss J. S. Bayliss, loc. cit., p. 17. 

 * Vide infra, Chap. X. 



H 



