FUNGI. 



17 



as having been observed in Agaricus Aueri by De 

 Seynes (PL It, fig, 3). 



Planchon observed in Agaricus ostreatus, grown in 

 the dark, an excessive formation of crowded twisted 

 branches, giving rise to botrytic and coralloid forms. 

 Klebahn describes and figures a somewhat similar case 

 in Triclioloma conglobatiim. 



Martelli figures what is perhaps one of the most 

 complex and copiously branched specimens ever seen. 

 This was in Agaricus coalescens var, cladonioides, in 

 which occurred fasciated branches of all grades, the 

 ultimate branches of all being in the form of small 

 stipes bearing tiny caps. He attributes the form to 

 lack of light and moisture. 



This same phenomenon occurs in the Polyporacese 

 when subjected to similar conditions. There is a 

 specimen in Kew Herbarium of Polijporus squamosus 

 forking palmately at the apex of the stipe, and another 

 one forking in stag's-horn fashion. Buller describes 

 good instances of the latter (PI. II, fig. 4), and Grillot 

 of P. umbellatus. 



The darkness in all these cases appears to induce 

 the outward manifestation of otherwise latent ancestral 

 features. For we find these abnormal forms occurring 

 elsewhere in the Fungi as perfectly normal structures, 

 viz., in the Clavariaceaa and Xylariaceas, and these 

 groups are regarded as simpler and older than the 

 Agaricaceae and Polyporaceas. 



There is one form, found for the first time in 

 Belgium, the branching of which is not due to darkness, 

 as it occurs in the light ; this is described by Roume- 

 guere under the name Boletus ramosus ; it is the 

 Polyjyorus imbricatus var. ramosus of Fries. It has 

 many cylindric branches covered with tubes. 



Fasciation. 



The occurrence, side by side with simple dichotomy, 

 of the more complex phenomenon of fasciation is met 

 vol. i. 2 



