532 FUNGI gress of knowledge was comparatively small for a period of nearly 250 years. But in 1821 ap- peared the Sy sterna Mycologicum of Elias Fries, a work of the most learned and profound char- acter, evincing a comprehensiveness and thor- oughness far surpassing all that had preceded it. It is even now the great work to which all students refer, though since that time a host of observers have been exploring this obscure field, and collecting a vast array of facts con- cerning the laws which govern these minute organisms. Montagne, L6 veille, Tulasne, Berke- ley, Desmazieres, and many others have of late years been engaged in the elucidation of their structure. The latest system given to the world is that in Berkeley's "Introduction to Oryptogamic Botany," which is essentially similar to that of Fries. The two principal divisions are : sporidiiferi, spores contained in special sacs called asci ; and sporiferi, spores naked, not enclosed. These are again subdi- vided into six principal orders, all formed on the mode in which the spores are borne, viz. : 1. Ascomycetes (Berk.), spores produced in little sacs (asci), and formed out of the protoplasm they contain. This order comprises a vast number of the black, pustular growths, abun- dant on dead wood, bark, twigs, leaves, &c. They are generally formed of a mass of carbon- ized cells arranged in the form of hollow spheres or cups called peritJiecia. Within these grow the asci containing the spores, which escape either from a pore in the perithe- cium or by its breaking up irregularly. The basal cells bearing the asci are collectively termed the Jiymenium. Among these are the mildews (erysiphe) and the black mildews (cap- nodiuni), and the whole great tribe of sphcerice. The truffles (tuber) also belong here. They are subterraneous, fleshy forms, whose substance is intersected by veins which are inward folds of the hymenium, covered by the expanding growth of the fleshy receptacle. The morels (morchella) and the helvellce are carnose, bulky forms, which have their asci on the outer sur- face of a variously folded, wrinkled, and pitted hymenium. The cyttaria is akin to these, of a sub-gelatinous consistence. These are all made up of compacted cells, forming horny, carbon- ized, or heavy, fleshy masses. 2. Physomycetes (Berk.), spores growing in bladder-shaped cells on the end of delicate, individual, scattered fibres, composed of cells applied to each other in a linear series. A small group comprising the true moulds (mucor). 3. Hyphomycetes (Fr.), spores naked, simple, or aggregated on the ends of fertile threads. These differ from the last in the naked growth of the spores. Here belongs the great host of minute moulds which cover almost every substance exposed to dampness with their floccose fibres. Nothing organic is free from their attacks. Their colors are sometimes extremely beautiful. To this order belong the mould of the potato rot (bo- trytis infestans), and many which induce decay in fruit (oidium), the bread and cheese moulds (penicillinm, aspergittus), the rigid black moulds (cladosporium, helminthosporium), and the yeast and vinegar plants, which are sub- merged mycelia of pencillium. (See FERMEN- TATION.) 4. Coniomycetes (Fr.), spores naked on the ends of filaments or vesicles ; hymenium 3 C 1. Wheat straw attacked by mildew, a, a. The stem, on which is the swelling &, from which has grown the sheath- like leaf c, o. 2. Cluster of spores of corn mildew magni- fied. 3. Single spore of corn mildew magnified 300 times. sometimes obsolete, sometimes contained in a perithecium. This order differs from the last in having scarcely any filamentous growth, and in having the spores produced in the utmost pro- fusion, greatly disproportionate to the rest of the plant. It comprises an infinity of minute pustular forms, which infest the tissues of every variety of plant, many presenting to the eye but a mere speck on their surface. Here belong the whole family of rusts, smuts, and bunt 1. Cluster of cups from the barberry magnified. 2. Same, from above. 3. Leaf of barberry, with a similar cluster. (puccinea, uredo, ustilago, tilletia, cecidium, &c.), which creep through the tissues of living plants, and finally burst forth on the exterior and fructify in dense, dusty masses, which cover their whole surfaces. Different species affect different organs, some being on stems and
