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. — The 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 •[ 

 38 1;.) 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.— The 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 



e.xists 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 ■ 1 1 " tube (a branch of the 



grows into the ovary, through winch the spermap,-i into the egg. 



, ' Magnified 3^0 diani. — 



sperm passes to the egg (fig. 307). After iicKan". 



A simple spermary arises either by the differentiation of 

 one of the ordinary cells, or of a special lateral branch, as in 



