318 BIOLOGY. [BooK iv. 



furnished with vibratile cilia; consequently they are in every 

 respect similar to the zoospores of the algae. But definitively, 

 the spores are formed at the expense of certain cells, and if they 

 are multiple they result from a repeated bipartition of this proto- 

 plasm. What matters it, after this, that they are produced or 

 not on the filaments of a mycelium, that they are gathered 

 together or not in the cavity of a receptacle, or sporangium, of 

 this form or of that ? 



The system of reproduction by oospheres and mobile anthero- 

 zoids exists also in the characese, the muscineae, and the ferns. 

 The form of the antherozoid varies, but usually it is a filament 

 more or less elongated, mobile, furnished or not with vibratile 

 cilia. Always the antherozoid is formed at the expense of the 

 protoplasm of special cells or antheridia whose wall is torn or 

 reabsorbed. Before the dehiscence or disappearance of this wall, 

 each antherozoid, habitually alone in the mother cell, is rolled two 

 or three times on itself (Fig. 45). As to the apparatus containing 

 the female corpuscules, they vary much in form, and have for that 

 reason received diverse names ; but generally the antherozoid s do 

 not penetrate into the receptacles of the oospheres (archegons) 

 except through a soft mucilaginous substance. Once in contact 

 with the oosphere or oospore, the antherozoid confounds itself 

 with it, and as happens usually after all fecundation, the oospore 

 segmentises itself by bipartition, and the embryonary develop- 

 ment follows its course. 1 



The phenomena of reproduction and fecundation are manifestly 

 the same in the phanerogams. We have already spoken of the 

 embryonary sac, of the embryonary cells which it contains. The 

 fecundating agent is no longer here an antherozoid ; it is the 

 granulated viscous substance (favilla) contained in the particles 

 of pollen. These particles are of very varied form, but have all 

 a double enveloping membrane (endhymenine, exhymenine). It 

 is well known that from contact with the humidity of the stigma, 



1 J. Sachs, loc. tit., pp. 391, 318, 401, 439. 



