464 



BOTANY 



PART II 



like depressions, or deep winding passages, or covered with a layer of tubes, closely 

 fitted together and lined by the hymenium. To this family belongs the genus 

 Boletus, occurring on the soil of woods, which has a large, thick-stalked pileus, 



FIG. 414-. Boletus Satanas. (After KROMBHOLZ, A nat. size.) Poisonous. 



covered on the under side with a layer of narrow dependent tubes. Although 

 many species of this genus are edible (e.g. B. edulis, B. badius, B. elegans, and 

 B. luteus), others are exceedingly poisonous, in particular B. Satanas (Fig. 414). 



Fm. 415. Femes igniarius. Section through an old FIG. 416. Psalliota campestri* ( = Aga- 



fructification, showing annual zones of growth, o, news campestris). Mushroom. To 



Point of attachment. ( nat. size.) the right a young fructification. 



(Reduced.) 



The stalk of the latter fungus is yellow to reddish-purple, or has red reticulate 

 markings, while the pileus, which may be 20 cm. wide, is yellowish-brown on its 

 upper surface, but on the under side is at first blood-red, becoming later orange- 

 red. B. felleus is unpleasant on account of its bitter taste ; it differs from B. edulis 

 in having bright rose - coloured tubes. Of the numerous species of the genus 



