Thallogens,] 



FUNGALES. 



33 



crusts of Tinea favosa and Porrigo lupinosa to be accompanied by moulds, Comjytes 

 Rend. Aug. 1841 ; and these observations have been extended by Dr. Bennett Trans. 

 Roy. Soc. Ed., vol. xv., Part 2, p. 277, who has also observed a mould growing' on the' 

 lining membrane or cheesy matter of tubercular cavities in the lungs of man ; as 

 also the development of a mould on the skin of living gold-fish. Much information 

 will be found on the subject in the place above quoted. 



In their simplest form Fungi are little articulated filaments, composed of simple 

 cellules placed end to end ; such is the mouldiness that is found upon various sub- 

 stances, the mildew of the Rose-bush, and, in short, all the tribes of 

 Mucor and Mucedo ; in some of these the joints disarticulate, and 

 appear to be capable of reproduction ; in others, spores collect in 

 the terminal joints, and are finally dispersed by the rapture of the 

 cellule that contained them. In a higher state of composition, 

 Fungi are masses of cellular tissue of a determmate figure, the 

 whole centre of which consists of spores attached, often four to- 

 gether, to the cellular tissue, which at length di-ies up, lea\'ing a 

 dust-Hke mass intermixed more or less with flocci, as in the puff- 

 balls, or sporidia contained in membranous tubes or asci, hke the 

 thecse of Lichens, as in the Sphserias. In their most complete state 

 they consist of two surfaces, one of which is even and imperforate, 

 like the cortical layer in Lichens ; the other separated into plates or ceUs, and called 

 the h\-menium, to whose component cells, wMch form a stratum resembling the pile of 

 velvet, the spores are attached by means of Httle processes, and generally in fours, 

 though occasionally the numl^er is either less or greater. ]Many of these cells remain 

 barren ; but after a time there 

 is a succession of fertile cells 

 constantly making its appear- 

 ance above the sui'face of the 

 h^-menium ; and, what is more 

 remarkable, the spicules or 

 sterigmata, which support and 

 give rise to the spores, have 

 been observed by Corda to pro- 

 duce a succession of fruit, a 

 new spore being produced where 

 the old one had fallen. This, 

 he informs us, is very easy of 

 observation in Agaricus plu- 

 teus. Besides the barren and 

 fertile cells, other bodies are 

 -observed which have been sup- 

 posed by authors to perform 

 the office of anthers. These 

 have long been known in the 

 dunghill Agarics, but they appear to be pretty generally distributed. The true struc- 

 ture of the more perfect Fungi has only been recognised within a few years, though 

 Miiller, half a century since, gave a correct figure of it m Agaricus comatus, and there 

 are indications of it scattered through many works. Leveille''s Memoir in Annales des 

 Sciences Naturelles, that of Berkeley in the Annals of Nat. History, of Phoebus in Nova 

 Acta Cses. Leop., and those of Berkeley and Tulasne in the Ann. of Nat. Hist, and 

 Ann. des Sc. Nat. on the fructification of Lycoperdons, as also that of the Messrs. 

 Tulasne on H^-pogaeous Fungi, may be consulted on this subject. 



Upon this kind of difference of structure. Fungi have not only been divided into 

 distinctly marked tribes, but it has been proposed to separate certain Orders from them 

 under the name of Byssacese, Gasteromyci, and Hypoxyla : the first comprehending 

 the filamentous Fungi found in cellars, and similar plants ; the second Lycoperdons 

 and the like ; and the third species which approach Lichens in the formation of a dis- 

 tinct nucleus for the sporules, such as Sphteria. But Fries considers the first as a 

 distinct group, and the two last as Fungi. 



Some writers have questioned the propriety of considering Fungi as plants, and 



Fig. XXI.— Botrj-tis curta. 



Fig. XXII. — 1. Spore-stalk of Agaricus elixus, with its four long sterigmata and small spores ; 2. 

 spore-stalks of Ag. semiovatus, with spores in various states of development ; 3. asci and sporidia of 

 Helvella elastica ; 4. sporidium of Tuber magnatum (Piedmontese Truffle), /Voh! a sketch hy Dr. Mon- 

 tague ; 5. sporidium of Peziza aurantia, with its two nuclei ; 6. single sporidium of Helvella elastica, 

 with a large globose nucleus. 



D 



