. Introduction to the study of fungi; their organography, classification, and distribution, for the use of collectors. Fungi. are parasitic on living vegetables. The Saprolegniaceae are aquatic. And the Entomophthoreae are entomogenous. The Mucoraceae might be mistaken for moulds if not more closely examined. The erect threads are not conidia-bearers, but sporangiophores, because they support sporangia at their tips; and these sporangia are nearly globose cells of thin membrane, which enclose the spores, or reproductive bodies (Fig. 104). When fully matured the sporangium is ruptured and the e
. Introduction to the study of fungi; their organography, classification, and distribution, for the use of collectors. Fungi. are parasitic on living vegetables. The Saprolegniaceae are aquatic. And the Entomophthoreae are entomogenous. The Mucoraceae might be mistaken for moulds if not more closely examined. The erect threads are not conidia-bearers, but sporangiophores, because they support sporangia at their tips; and these sporangia are nearly globose cells of thin membrane, which enclose the spores, or reproductive bodies (Fig. 104). When fully matured the sporangium is ruptured and the enclosed spores escape. This is the ordinary asexual repro- duction of the Mucors, and all that was really known of them half a century ago. In some ,, . ... . J s . , . Fia. 104.— Mucor. cases the fertile branch, or sporangiophore, is prolonged into the interior of the sporangium, and becomes a columella. The sexual reproduction of the Mucoraceae is accomplished by zygospores, resulting from conjugation, and hence they are sometimes characterised as Zygomycetes. In many of the species this form of reproduction has never been traced, but has been accepted from analogy. Two lateral branches resembling each other, and termed archicarps, are concerned in the process. They resemble at first ordinary branches, which approach each other until the tips meet, but as they increase in size they become clavate, and are densely filled with protoplasm. At length the ex- treme portion of each archicarp is separated from the basal portion by a transverse septum, each portion acquir- ing a distinctive name, the basal cell being termed the suspensor, and the apical cell the gamete (Fig. 105). At the point where the two gametes meet the separating cell-walls are. Fig. 105.—Formation of Zygospore. After De Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not p
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