FUNGI. 



[ 345 ] 



FUNGI. 



mycelium ; but their spore-bearing cells ap- 

 pear as definite groups of vesicles or sacs of 

 elongated form, producing spomles (usually 

 eight but sometimes two, multiples of two, 

 or multiples of eight) in their cavities. In 

 the Truffles (Tuber, Elaphomyces, fig. 185), 

 &c. the sporidia are found in twos, fours, or 

 eights, in sacs in the internal convoluted 

 substance ; while in the Puff-balls, except 

 Scleroderma, where the internal mass finally 

 breaks up into powder, the spores are deve- 

 loped free, as in the Agarics &c. More 

 minute accounts of these structures will be 

 found under THECASPORES and the various 

 genera. 



It was long imagined that these two 

 modes of producing the spores afforded a 

 firm basis for the classification of the Fungi ; 

 but recent discoveries seem to indicate that 

 characters derived from the fructification 

 are as unsafe here as in the Alga3. Thus, 

 if De Bary's observations on Agancus are 

 correct, an asciferous structure occurs in the 

 highest group ^of the basidiosporous classes. 

 It is now, however, pretty certain that the 

 ascigerous structure which he found on 

 Agaricus mellem was a species of Hypho- 

 myces. The orders Coniomycetes and As- 

 comycetes also are confounded together by 

 the numerous genera which exhibit both 

 asci and sfy/ospores, although the latter may 

 perhaps be regarded as merely a modifica- 

 tion of the ascosporous structure. Tulasne 

 has also pointed out a peculiar structure 

 analogous to the so-called spermatozoids of 

 the Lichens, namely very minute cylindrical 

 bodies growing upon free points from the 

 fructifying surfaces of the Fungi; these 

 bodies, quite distinct from the basidiospores 

 and thecaspores, are called spermatia (PI. 26. 

 figs. 3, 4, 17 s). According to Cornu, these 

 germinate. 



Certain more recent observations on the 

 sexual reproduction of the Fungi require 

 special notice. 



In the Saprolegniae, this has been de- 

 scribed under ACHLYA. In Cystopus, the 

 conidia are stated to be formed at the ends 

 of the branches. Subsequently sporangia 

 or oogonia are produced by the swelling 

 of the ends of branches of the mycelium ; 

 while on another branch, a shoot grows to- 

 wards the sporangium, swells, and forms 

 an antheridium. A fine tube from this 

 bores through the sporangium, and pro- 

 duces fertilization. 



In the Ascomycetes, a mycelium is formed 

 from the true spores ; on this are produced 



conidia, which again produce mycelium. 

 On this are ultimately produced sexual 

 organs, consisting of the pollinodium or 

 antheridium, and the carpogonium or spo- 

 range : these are often much alike, but the 

 latter is usually larger, and composed of 

 more numerous cells. The pollinodium 

 forms a slender branched cell, not contain- 

 ing spermatozoids. It comes in contact at 

 the apex or through its whole length with 

 the sporange, which it fertilizes by diffu- 

 sion, as in the pollen-tube of the embryo- 

 sac ; but there is no fusion of contents. 



In Ascobolus, the carpogonium or spo- 

 range consists of a curved row of cells. 

 The slender branches of the pollinodium 

 become closely applied to and fertilize it. 

 After this, one of the middle cells of the 

 carpogonium grows more than the others, 

 and produces buds which ultimately form 

 the asci. 



In Peziza, the end-joints of the carpogo- 

 nial branches form ovate vesicles with an 

 apical appendage. The slender wedge- 

 shaped pollinodium arises on the same 

 branches beneath the carpogonium, with 

 which it becomes connected. Numerous 

 filaments then spring from the base of the 

 sexual organs, forming a dense network 

 the hymenial layer, in which the asci are 

 subsequently produced. It appears that 

 Botrytis cinerea is a conidiiferous form of 

 Peziza (Fuckeliana). A remarkable pecu- 

 liarity in the sexual formation of spores in 

 many Fungi, as in some Algae is, they are 

 frequently not formed in the directly ferti- 

 lized cell, but in the newly formed cells 

 springing from its sides or base. 



The sexuality of the Ascomycetes, how- 

 ever, is disputed. 



Zoospores have now been discovered in 

 PERONOSPORA and CYSTOPUS. 



The minutiae of the structure of the Fungi 

 may be treated most satisfactorily under the 

 heads of the orders (ASCOMYCETES, CONIO- 

 MYCETES &c.), since the elements are very 

 similar in all, while the modes of combina- 

 tion are very varied, and in most cases 

 peculiar to the families. 



In consequence of the numerous disco- 

 veries of Tulasne, De Bary and others, the 

 older arrangement of the Fungi, based upon 

 the views of Fries, is not at present satis- 

 factory. We adopt, therefore, that of Sachs, 

 slightly modified; retaining, however, in 

 great measure the nomenclature for those 

 Fungi which are manifestly merely states 

 of higher forms, and are not autonomous. 



