78 Prof. H. Karsten on the Fecundation of the Fungi. 



as it appears to be, from analogy with Ccenogonium. I could 

 ascertain from it only that the outermost envelope of mycelium- 

 filaments which forms over the central cell, and is comparable 

 to the outer cortical layer of the apothecium of Ccenogonium ^ 

 becomes the general veil (velum universale) of the Agaricus 

 vaginatus ; further_, that with the first development of the young 

 fruit, which is soon of a globular form, the portion destined to 

 form the peduncle of the developing fruit is produced by the 

 increase and interlacing of the mycelium-filaments, especially 

 those beneath the ovicell; and that the greatest accumulation 

 of plasma occurs in the elongated cells which are here present; 

 so that, probably, the most active formation of new cells takes 

 place at first at the apex of this part of the peduncle (which is 

 situated beneath the general veil), and soon afterwards a little 

 below its apex. 



Whether this cambial tissue is produced somewhat as in 

 Ccenogonium, from the nuclear cell which was contained in the 

 ovicell, is a question which cannot yet be solved with cer- 

 tainty, although it will most probably be answered in the 

 affirmative. 



If this be the mode of development of the fruit in the Hy- 

 menomycetes, it will present the following difi'erences from 

 that of Ccenogonium : — 



In the apothecium of these Lichens (which, until it opens at 

 the vertex and becomes expanded into a nearly flat disk bearing 

 the hymenium, likewise forms a globular and completely closed 

 body), the new generations produced in the fecundated central 

 cell of the naked archegonium, which finally contain the spores 

 as the last member of this series of cell- developments, are so 

 arranged in the centre of the young fruit that all the spore- 

 tubes lie in a radial direction. 



Each of these numerous tubes produced from the fecundated 

 germ-cell of the Lichen becomes united at its base (hitherto 



the archegonium, which, even in the Algae, generally occurs without an 

 envelope. Hence this primitive mother cell of the Fungus-fruit, if we do 

 not apply to it the general denomination of '' ovicell," must be named the 

 " archegonium," or perhaps, to distinguish it from that concealed in a 

 simjjle stratum of cells, the " naked archegonium," as I have already ex- 

 plained (Bot. Untersuchungen, p. 91). 



To give the name of " oogonium " to this organ on account of its want 

 of an envelope, is just as unnecessary, and therefore unscientific, as to 

 name the naked nucleus differently from that with one envelope, and this, 

 again, differently from that with several coats. Who would now approve, 

 if some one were to give different names to the simple scale-like leaf of 

 the mosses, and to the linear grass-leaf, or the simple pedunculated leaf 

 of a myrtle, and, again, a different name to the latter and to the composite 

 leaf of the Leguminosae, &c. 



