. Plant life, considered with special references to form and function. Plant physiology. SEXUAL KEPKODUCriOX. 2/7 the form of the S]ierm is usually that of the cell in which it is produced. If it is set free, it may become globular, and have slo\\' amceboid movements, or it may be entirely im- motile. In the latter case it must depend upon the move- ments of the water into which it escapies for transference to the vicinity of the egg. The sperm may be ovoid and fur- nished at the end with one or more cilia; or elongated and bent or coiled one or more times. The elongated forms have almost iiiv
. Plant life, considered with special references to form and function. Plant physiology. SEXUAL KEPKODUCriOX. 2/7 the form of the S]ierm is usually that of the cell in which it is produced. If it is set free, it may become globular, and have slo\\' amceboid movements, or it may be entirely im- motile. In the latter case it must depend upon the move- ments of the water into which it escapies for transference to the vicinity of the egg. The sperm may be ovoid and fur- nished at the end with one or more cilia; or elongated and bent or coiled one or more times. The elongated forms have almost iiivarialilv two to many cilia (fig. 306). 381. The spermary.âThe organ in which the sperms are produced is the spei'mavy or antheridium. It is either simple or comjiound. A simple spermary consists of a single cell whose contents is transformed into one or more sperms. Simple spermaries occur only in algre and fungi, and by reduction among seed plants. (See â¢[ 381;.) If more than one sperm is to be formed, the nucleus, originalh' single, becomes di\ided into as man^⢠parts as there are to be s]ierms (sometimes into more than become mature). The total number of sperms produced by a plant is \ \ / related somewhat to the number of eggs, \ (^ ///^ but ijarticularlv to the chances of the ^\ sperms reaching the egg. ''' .,. , .":"." ^ Fig. 307.âThe sex organs It there is but a single sperm formed of /v>-,.«M/,.r,i. h, , , -11 1 r hvpha which has de\-el- Dy each spermary, either the number of oped at the end the , . o\an". 0. containing a spermaries is great or some adaptation single egg (the ceinral ^ , *" . p ^ . dark sphere*. //'. h^'pha lor the certain transfer of the sperm which has developed the _ -^ .... sperinar\'. /^ whose pro- tO the tgS,. In (. ystnpUS and its allies, toplasm: constituting a . , - , single sperm, is passing for instance, a branch of the spermary through the fertilizing , 1 1 â 1 1 " tube (a branch of the gr
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