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



The supposition that the mode of development ascertained, 

 indeed, only from this single example occurs also in the other 

 composite fruits of the Lichens and Fungi, is supported by the 

 analogous development of the fruits of the leafy cellular Cryp- 

 togamia. 



In Mosses and Liverworts the germ-cell contained in the 

 archegoniura, after fecundation by means of antherozoids in the 

 same way as in vascular Cryptogamia, multiplies into a great 

 number of seeds and at the same time becomes developed into 

 an envelope for these, constructed with so many modifications 

 that until recently it could be almost exclusively employed for 

 the classification of these plants. In like manner, if the result 

 obtained in the case of Ccenoffonium be found to apply also to 

 the other Lichens and Fungi, the fertilized germ-cell of these 

 also grows into a fruit of complicated structure, usually serving 

 as an envelope to innumerable seeds, and here also presenting 

 itself in such multifarious forms that it has likewise been em- 

 ployed in systematic botany for the arrangement of the Fungi 

 in genera and families. 



Between the two great divisions of the Cryptogamia esta- 

 blished in accordance with their histological structure and the 

 formation of their fruits, the vascular and cellular Cryptogamia, 

 the Algse, hitherto likewise but imperfectly known as regards 

 the development of their fruit, would apparently take their 

 place. 



In order to test these ideas, as soon as I had completed the 

 investigation of Coenogonium, I undertook the dissection and 

 observation of the developmental history of the fi-uits of Fungi, 

 although in their earliest stages these organs (which, from their 

 great delicacy, elude dissection, and by the inclusion of air in 

 all the larger interstices of their loose tissue become opaque) 

 present to the anatomist even greater difficulties than the fruit 

 of the lichens, which from their smallness alone are so difficult 

 to dissect that several recent authors have been unsuccessful in 

 performing this operation. 



In Agaricus campestris, Linn., by gradually going back from 

 the forms recognizable with certainty as the youngest states of 

 the cap to smaller ones, I found an organ which, from its pecu- 

 liar form and texture, I could not but regard as the first com- 

 mencement of the fruit. This was an oval, almost egg-shaped 

 simple cell, standing upon a short peduncle of the thickness of 

 the mycelium, and of from three to four times the diameter of 

 this, filled with albuminous matter and overgrown by filaments 

 of the mycelium, which were at first single, but by continually 

 increasing in number, at last form a thick rind (peridium, velum) 



