. Introduction to the study of fungi, their organography, classification, and distribution for the use of collectors . ion, and serve to infectfresh hosts. ^ Infection results from contact of one of the conidia whichadheres to the surface of the host, germinates there, and thegerm-thread enters the body. Afterentering, growth proceeds rapidlyand forms liyphal bodies (), which are short thick fragmentsof variable size and shape, continuallyreproduced by budding, until thebody of the host is more or lesscompletely filled with them. Havingabsorbed the contents of the body,these hyphal bodi
. Introduction to the study of fungi, their organography, classification, and distribution for the use of collectors . ion, and serve to infectfresh hosts. ^ Infection results from contact of one of the conidia whichadheres to the surface of the host, germinates there, and thegerm-thread enters the body. Afterentering, growth proceeds rapidlyand forms liyphal bodies (), which are short thick fragmentsof variable size and shape, continuallyreproduced by budding, until thebody of the host is more or lesscompletely filled with them. Havingabsorbed the contents of the body,these hyphal bodies germinate, eachone producing one or more threads,which proceeds directly into theouter air, and bears its conidia, orit branches indefinitely, each branch-let producing spores at the extremity(Fig. 111). These are the conidia-bearers, and their results the simpleasexual reproduction. Conidia areformed by constriction or budding,and when fully matured are forcibly ejected to a considerabledistance. The discharged conidium germinates at once, but, 1 Thaxter On the Entomophtlwreac of the United States, 4to, Fiu. 111.—Conidiopliores ofEiitomophtlioi-a. S. P. C. K. 236 INTRODUCTION TO THE STUDY OF FUNGI failing to reach a suitable host, a secondaiy conidium is formed,resembling that from whence it was derived (Fig. 112).Should this second fail in finding a suitable host, a third isformed from the second in the same manner. The other form of reproduction is by means of restingspores, which may be sexual orasexual, and proceeds also from thehyphal bodies. The latter, orazygospores, are formed by theconversion of a hyphal body into aresting spore, or by direct buddingtlierefrom (Fig. 113). They areusually spherical, rather large, sur-rounded by triple walls. Sexualresting spores, or zygospores, areproduced as the result of conjuga-tion of opposite threads. Threadseither within or without the bodyof the host produce lateral ovit-growths, at opposite points of twodifferent th
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