20 



PRINCIPLES OF PLANT-TERATOLOGY. 



The margin of the cap had then extended beyond this, 

 forming a new set of gills ; hence the presence of the 

 lower " ring." 



It was stated above that the abnormal growth in the 

 dark of certain Agaricacse and Polyporacese was often 

 largely clue to extreme extenuation of the stipes ; this 

 may, in fact, occur without any branching whatsoever. 

 In the case of the Polyporacese it would seem, as in 

 the case of the Ganoderma described by van Bambeke, 

 that the cap also forms part of the proliferated portion, 

 and represents a persistence of the embryonic condition 

 of the spore-bearing tissue. 



Brefeld describes four-foot long proliferations of the 

 stipe of Coprinus stercorarivs when grown in the dark. 

 Buller also describes proliferation of the stipe, in 

 correlation with non-formation of the cap, in Lentinus 

 lepideus (PI. II, fig. 6). This type of proliferation is 

 obviously the simplest of all. It may be compared with 

 the extreme cases of vegetative proliferation of the 

 inflorescence in the higher plants. It doubtless repre- 

 sents an attempt on the part of the stipe to reach the 

 light. 



We must next mention those cases in which prolife- 

 ration takes place at the reverse end, viz. from the 

 base of the stipe. Where the upper surface of the caps 

 of two individuals become fused at an early stage, 

 owing to their growing in very close contiguity, the 

 stronger of the two sometimes wrenches the weaker, 

 stipe and all, away from attachment to the mycelium 

 in the substratum, and at the same time, owing to the 

 expansion and upturning of the cap of the larger 

 specimen, the smaller one comes eventually into a 

 completely inverted position with its stipe directed 

 upwards (PI. I, fig. 2). 



Now Trog observed, in a case like that just described, 

 in Agaricus ahttaceus, that from the basal end of the 

 inverted stipe a new cap developed. Hence the curious 

 object presented of three caps one above the other. 

 Biers describes a similar case in Boletus edulis, and he 



