Introduction to the study of fungi : their organography, classification, and distribution for the use of collectors . own of them half a century ago. In somecases the fertile branch, or sporangiophore, isprolonged into the interior of the sporangium and becomes acolumella. The sexual reproduction of the Mucoraceae is accomplishedby zygospores, resulting from conjugation, and hence they aresometimes characterised as Zygoiiiycctes. In many of the speciesthis form of reproduction has never been traced, but has beenaccepted from analogy. Two lateral branches resembling eachother, and termed archic
Introduction to the study of fungi : their organography, classification, and distribution for the use of collectors . own of them half a century ago. In somecases the fertile branch, or sporangiophore, isprolonged into the interior of the sporangium and becomes acolumella. The sexual reproduction of the Mucoraceae is accomplishedby zygospores, resulting from conjugation, and hence they aresometimes characterised as Zygoiiiycctes. In many of the speciesthis form of reproduction has never been traced, but has beenaccepted from analogy. Two lateral branches resembling eachother, and termed archicarps, are concerned in the resemble at first ordinary branches, which approach eachother until the tips meet, Ijut as they increase in size they become clavate, andare densely filledwith lengtli the ex-treme portion ofeacli archicarp isseparated from thebasal portion by atransverse septum,each portion acquir-ing a distinctivename, the basal cellbeing termed thesuspensor, and the apical cell the//amc^^e (Fig. 105). At thepoint where the two gametes meet the separating cell-walls are ///. Fig. 105.—Formation of Zygospore. After De Baiy. 230 INTRODUCTION TO THE STUDY OF FUNGI soon dissolved, so that the contents coalesce, and a single cell isconstituted from the union of the two gametes, which is, ineffect, the young zygospore. Henceforward the cell-wall ofthe zygospore becomes thickened, and coloured, so that itusually acquires a brown colour, and is warted or spinulosewhen mature. The zygospores thus formed are also character-ised as resting spores, because they are capable of resting, orremaining in a dormant condition for months before germina-tion takes place, usually through the winter, becoming activein the spring. It may sometimes happen that the two gametes, instead ofcoalescing, remain distinct; or in rare cases only one archicarpis produced; yet in such instances a body resembling azygospore is developed, without conjugation, and therefore t
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