897 



FUNGI. 



FUNGI. 



experimental observer may indeed discover that Fungi will regularly 

 develop in one kind of chemical mixture and not in another. Dutro- 

 chet, for example, found that, if he acidulated a weak solution of 

 white of egg, different species of Manilla rapidly formed upon it ; 

 while, if he rendered such a solution slightly alkaline, the genus 

 Jiat t'ijtis made its appearance ; and that the solution in its simple state, 

 neither alkalescent nor acidulated, produced no Fungi a remarkable 

 circumstance enough. But it would be too much to infer from such 

 an experiment " that invisible germs of a filamentous plant may be 

 created by the chemical action of an acid or an alkali on organic 

 matter dissolved in water, and that they develop by virtue of the 

 vital action which would be the necessary attribute of the chemico- 

 organic molecular compound." On the contrary, the experiment only 

 showed that the seeds of Funyi, like those of other plants, require 

 special soils in which to grow ; that Botrytii will not grow in acid 

 mucilage, nor Manilla in alkaline, nor either in mucilage in a neuter 

 state. This ia only what happens in plants of a more highly-organised 

 nature. Who ever saw the horned-poppy of the sea-shore growing 

 spontaneously in an inland field, the marsh-marigold on a dry heath, 

 or the reindeer-lichen of Lapland on a heath in Italy ? Let any one 

 take a few different kinds of seeds, and commit them all to the ground 

 in the same place ; some will spring up and flourish, others will just 

 appear above ground and then perish, others will make an attempt to 

 germinate. This, an every-d:iy event, is a sufficient explanation of 

 the fact elicited by SI. Dutrochet's experiment. Every kind of seed 

 has something specific in its nature, in consequence of which it requires 

 particular kinds of soil, and some special combination of heat, light, 

 and moisture, to be roused into a state of vegetation. As to the 

 presence of the seeds of Hulrytit and Manilla in the vessels in which 

 M. Dutrochet's experiments were conducted, it is perfectly easy to 

 conceive that the seeds of such common plants exist everywhere sus- 

 pended in the air or adhering to the cleanest vessels ; they are so 

 numerous as to baffle all powers of calculation ; they are so minute 

 as only to become visible when aggregated in masses of many 

 thousands ; and so generally dispersed that it is difficult to con- 

 ceive a place in which they may not be reasonably supposed to exist. 

 Tin: very genenil existence of dry-rot is no weak evidence of this. 

 [DRY-HOT.] - 



Fiwji are among the most numerous of all plants in regard to 

 genera and species. Mr. Berkeley gives the number of genera "as 598, 

 and the species as 4000 ; but new forms are constantly being added 

 to those already known. It is generally asserted that they are uncom- 

 mon iu tropical countries, but it is doubtful whether this is true, as 

 recent travellers have brought home collections as well as indicated 

 the existence of many forms in tropical climates. 



They usually prefer damp, dark, un ventilated places, such as cellars, 

 vaults, the parts beneath decaying bark, the hollows of trees, the 

 denser parts of woods and forests, or any decaying matter placed in 

 a damp and shaded situation ; and are most especially averse to dry- 

 ness and bright light. Even when they appear upon the live leaves 

 of trees, the stems of corn, or in similar situations, it is either at the 

 damp and wet season of the year, late in the autumn, or in damp and 

 shaded places ; and M. Audouiu has shown experimentally that when 

 live injects are attacked by them it is only when they are confined in 

 damp unventilated places. (' Comptes Kendus,' 1837.) In stations 

 favourable to their multiplication they often commit extensive ravages, 

 attacking and destroying timber, and producing decay in all kinds of 

 vegetable matter of a soft and succulent nature ; nor is it to dead 

 matter that their ravages are confined. They sometimes fix them- 

 selves upon live insects, producing great havoc among the silkworms 

 in the manufactories of Italy, and are probably the cause of a more 

 extensive destruction of such animals than we at present have any 

 idea of. Under the name of mildew and blight they commit excessive 

 damage among living plants, as the farmer and orchardist know too 

 well to their cost. 



There is frequently considerable difficulty in distinguishing Fungi 

 from the other forms of C'ryptogamic Plants. They are distinguished 

 from Lichens by their more fugitive nature, their more succulent 

 texture, their want of a thallus or expansion independent of the part 

 that bears the reproductive matter, but more particularly in their 

 never containing germs distinct from the fructifying bodies of a 

 vegetable germ so constant in Lichens. 



From some forms of Alga: they differ very little, but the most 

 obvious distinction is th'eir mode of growth. The Alijte like the 

 Lichens do not derive their nutriment from the bodies on which they 

 grow, which is the case with all the Fungi. There are however 

 certain free forms of Fungi which it is difficult to distinguish from 

 Alyce by this character ; such are the moulds which are developed in 

 ink, milk, and other liquids. 



It has been stated that Fungi are distinguished from Algir by the 

 absence of spontaneous movements. It is no doubt true that the 

 nii'litiun of the protein which is the motile agent in all plants is 

 dill'erait in Fungi from what it is iu Alga-, but this is no general 

 : :tion. In those Fungi which are developed in water, in one 

 instance at least, the A Mi/a prolifera, or Sajiraleynia fera.c [Aciu.vA ; 

 H.\i'iioi.K<;su], tin; movements of the spores are as active as in any 

 of the A tijit. 



"In tin! simplest form Funyi are little articulated filaments com- 



H AT. HIST. DIV. VOL. II. 



posed of simple cellules placed end to end. Such is the mouldiuess 

 that is found upon various substances, the mildew of the rose-bush, 

 and in short all the tribes of Mucor and Mueeda. In some of these 

 the joints disarticulate, and appear to be capable of reproduction; iu 

 others spores collect iu the terminal joints, and are finally dispersed 

 by the rupture of the cellule that contained them. Iu a higher state 

 of composition Fungi are masses of cellular tissue of a determinate 

 figure, the whole centre of which consists of spores attached, often 

 four together, to the cellular tissue, which at length dries up, leaving a 

 dust-like mass intermixed more or less with flocci, as iu the puff-balls, 

 or sporidia, contained in membranous tubes or asci, like the thecse of 

 Lichens, as in the Sphserias. In their most complete state they con- 

 sist of two surfaces, one of which is even and imperforate, like the 

 cortical layer of Lichens ; the other separated into plates or cells and 

 called the hymenium, to whose component cells, which form a 

 stratum resembling the pile of velvet, the spores are attached by 

 means of little processes, and generally in fours, though occasionally 

 the number is either less or greater." (Lindley.) 



The following is Schleiden's account of the development of the 

 organs of reproduction in the Fungi : 



" The most simple (Hyphomycetes, filamentous Funyi) form, at the 

 end of the thread-like cells, narrower protuberances, in each of which 

 a spore is developed : this at length separates, having consequently a 

 double membrane, the cell of the spore itself and the covering 

 (sporangium) arising from the parent cell, as, for instance, in Pent- 

 cUlium and Jiott-ytis. In others the thread-like cells form a spheric.il 

 swelling at the extremity, from which project a number of such. 

 prolongations, each of which contains a spore, while the whole forms 

 a divided sporangium, as for instance, in Mucor and Penicillium. 



"In others (Ooateromycetet, the ventricular Fungi) the tlireail-likc 

 cells combine into pointed, or non-pointed, variously-shaped sporo- 

 carps ; in or upon which are spores, of the development of which we 

 know nothing. After the scattering of the spores, the thread-like 

 cells often remain as tender wool, as iu the Ti-ichiacete, or as a delicate 

 network (capillitium), as, for instance, in Stemonitis, Oribraria ; and 

 the external capsule (uterus peridium) generally composed of. fine 

 filamentous cells, is then dissolved, or bursts in different regular 

 ways, as in Arcyria and Getalrum. 



" In the most highly developed Fungi(Ifi/menomi/cetcs, membranous 

 Fungi), elongated pouch-like cells (probably only the ends of the 

 interwoven filiform fungus-cells, developed into the sporocarps, or 

 cells formed at the ends of these cells) combine by arrangement side 

 by side so closely as to form a membrane (hymeniuin). Sorno of the 

 cells of this membrane enlarge considerably (sporangia), and send 

 out from one to six points at their free extremity, in each of which a 

 spore is developed. The filiform cells of the fungus then either form 

 round masses, closed in all round (sporocarps), with cavities in their 

 interior, the walls of which are clothed by the hymenium, or they 

 form definitely arranged columns in Merisma, tubes iu Polyporut, or 

 lamella; in Dcedalea and Ayaricus, which are clothed by the hyme- 

 nium, as in the Hymenomycetes. Of the latter we only know, with 

 any amount of accuracy, the law of development relating to the Toad- 

 stools, and more especially that of the Ayaricinete. Iu these latter 

 there are formed, at definite parts of the flocculent mycelium, small 

 hollow heads (volvjc), at the bottom of the cavity of which there grows a 

 corpuscle, shortly pedunculated below, .and enlarged into a spherical 

 form at the top. In the lower part of this protuberance a horizontal 

 circular cavity is formed, to the upper surface of which are attached 

 the tubes, lamellae, &c., which bear the hymeuiiun. The bottom of 

 the cavity is only formed by a membrane (indusium), which is either 

 separated from the pedicel on its further development, or, loosening 

 itself from it and the upper part at the same time, remains as a 

 membranous ring (annulus) upon the stalk. The upper part, which 

 supports the hymenium on its lower surface, dilates subsequently, 

 and appears as an umbrella-like expansion, called the cap (pileus). 

 The whole then breaks through the volva, which is very soon 

 dissolved." 



During their growth the same Funyi assume very different forma 

 and appearances. It thus happens that the same species has not only 

 been described under different specific names, but even referred to 

 different genera. Fries states that he has traced no less than eight 

 genera of different authors to mere degenerations or imperfect states 

 of Tkdep/iora sulphured. Nees von Esenbeck also states that the same 

 fungoid matter which produces Sclerotium mycctospora in the winter, 

 developes Agaricus volvaceus iu the summer. Professor Henslow has 

 also shown that some of the supposed species of Undo are forms of 

 Puccinia, Arcgma, &c. Kiitzing, in an essay on the ' Transformations 

 of Plants,' carries his views on this subject very far, and maintains 

 that according to different circumstances the same species will 

 produce A lg<t, Fungi, Lichens, or Mosses. 



In the article ENTOFHYTA will be found an account of the plants 

 growing on man and living animals. Many of these are Fungi. 

 Professor Balfour, in his ' Class-Book of Botany,' gives the following 

 account of diseases in plants produced by Funyi : 



"The attacks of Parasitic Fungi cause extensive injury and disease 

 in plants. Some think that the spores of Funyi coming into contact 

 with the plant act both as the predisposing and exciting cause of 

 disease ; others, perhaps more correctly, think that some change is 



3 M 



