GROWTH OF FUNGI. 



427 



somewhat enlarged at c, to the right above : the apex of this consists of a growing- 

 point, while the lower portion is already in process of elongation. The somewhat 

 older fructification represented at II 

 and /// is commencing to form the 

 umbrella-like expansion {pikus) at its 

 apex, the elongation at the top ceasing 

 meanwhile; hence the mass of tissue 

 becomes extended radially all round 

 the growing-point, as shown still fur- 

 ther developed at IV. The embryonic 

 character of the fungal tissue now dis- 

 appears at the apex and on the upper 

 side generally of the developing pileus, 

 but is maintained for some time longer on 

 its lower surface, from which very nu- 

 merous thin lamellae now grow out, radi- 

 ating from the stem to the periphery 01 

 the pileus. From these the reproductive 

 organs are developed. It is not diffi- 

 cult to recognise in the processes ot 

 growth briefly indicated in Agaricus, 

 relations similar in the main to those 

 which we meet with in the more highly 

 organised plants, which is in this case 

 so much the more remarkable since the 

 mycelium and the fructification of the 

 Fungus consists of single filaments or 

 hyphos, each individual one of which 

 represents as it were an independent 

 growing plant, in which growing-points 

 and the various phases of growth are to 

 be observed, as in the Mould-fungi. 

 In the mycelium and fructification of 

 the present Fungus, however, hundreds 

 and thousands of such hyphse are com- 

 bined in such a manner that all their 

 growing-points become united in the 

 growing-point of a branch of the my- 

 celium, or that of an organ of repro- 

 duction. 



It would not be difficult to find 

 dozens of other cases among the Fungi 

 andAlgse in which the typical processes of 

 growth still make their appearance^ it is 



true, here and there, but in which they yet are replaced more or less by widely different 

 arrangements. As a particularly striking example in this direction, I may mention one 



Fig. ■zS^.—Agaytcus variecolor. I Mycelium 

 ( w) with young fructification a and * (nat. size) ; c one 

 of the latter in longitudinal section (magii.). // older 

 fructification, the pileus is beginning to be formed. 

 /// the same in longitudinal section. IV the pileus 

 further developed ; -v velum. The lines in the longi- 

 tudinal sections indicate the course of the hypliee. 



tical section of a young fructification 

 npudiciis (cf. the text— i nat. size). 



