. Botany for high schools and colleges. Botany. 238 BOTANT. The steps in the process in Mucor stolonifer are briefly as follows : two hyphae come near each other, and send out small branches, which come in contact with each other {a, Big. 160) ; these elongate and become club-shaped, and at the same time they become more closely united to each other at their larger extremities {i, Fig. 160); a little later a trans- verse partition forms in each at a little distance from their place of union (c. Pig. 160) ; the wall separating the new terminal cells is now absorbed, and their protoplasmic con-
. Botany for high schools and colleges. Botany. 238 BOTANT. The steps in the process in Mucor stolonifer are briefly as follows : two hyphae come near each other, and send out small branches, which come in contact with each other {a, Big. 160) ; these elongate and become club-shaped, and at the same time they become more closely united to each other at their larger extremities {i, Fig. 160); a little later a trans- verse partition forms in each at a little distance from their place of union (c. Pig. 160) ; the wall separating the new terminal cells is now absorbed, and their protoplasmic con- tents unite into one common mass {d. Fig. 160); the last stage of the process is the secretion of a thick wall around the new mass, thus forming a zygospore (e. Fig. 160, and z, Fig. 161). It is interesting and instructive to note here the close simi- larity between the zygospore of Mucor stolonifer and that of Mesocarpus, briefly described above (par. 314). In both the zygospore is formed in the lateral branches of the ordinary filaments. 320.âIn Piptocephalis the for- mation of the zygospore is essen- tially like that in Mucor, with some minor differences. The uniting hypha-branches are large and curved, and are smaller at their points of union; the zygo- Fig. ,«, of Mv. spore is formed at first in the «»â ; m, Praoti. ^^^^^l neck formed by the union of the tips of the branches, but it soon grows so much as to appear to be external {Z, Fig. 162). In this, as in all other cases, however, the zygospore is strictly an endogenous for- mation. " The zygospore does not gei'minate until it has under- gone desiccation, and has experienced a certain period of rest,"* when, if placed in a moist atmosphere, it sends out hyphae which bear sporangia. The zygospores appear never * "Researches on the Mucorini," by Ph. Van Tieghem and G. Le Monnier (translated in Quarterly Journal of Microscopical Science, 1874, p. 49), upon whiol
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