342 PROCEEDINGS OP SECTION D. 



b. The oosperm undergoes fission, forming flagellulse (swarm 

 cells) which afterwards germinate. Coleochcete. 



3. Ovum produced by rejuvenescence of part, or the whole of 

 the protoplasm of a unicellular ovary. No sperms developed, 

 but the micro-gamete is represented by part of the unicellular 

 spermary. Pevonosporeoi. 



4. Ovary multicellular producing one or more ova by differentia- 

 tion of one or more of its cells. Spermary multicellular, 

 sperms formed from the nucleus and a portion of the proto- 

 plasm of certain of its cells. Zygote gives rise to the adult, 

 or to the blastobium in cases of meta-genesis, by repeated fission. 



i. One ovum to each ovary : sperms always ciliate. 

 Characece, Muscinece, Vascular Cryptoganes. 



ii. Ovary usually produces more than one ovum : 

 sperms visually ciliate, but may be amceboid or 

 non-motile. Metazoa. 



jS. Ovary more or less degenerate, producing a single 

 ovum. Spermary degenerate, producing no sperms, 

 but efiecting fertilization by one of the products of 

 division of its nucleus. Zygote an oosperm, forming 

 the adult organism (blastobium) by repeated fission. 



Phanerogams. 



y. The protoplasm of the ovary does not become differ- 

 entiated into an ovum, and in consequence the 

 zygote never assumes the form of a distinct oosperm. 



1. The ovary is provided with a reception portion (trichogyne) : 

 the spermary gives rise to non-motile sperms. 



i. Ovary and spermary unicellular : zygote divides 

 into amoebulee w'hich come to rest and ger- 

 minate. Baiigiacece. 



ii. Ovary and spermary unicellular : zygote divides 

 repeatedly forming spores. JVemalion. 



iii. Ovary multicellular : after fertilization two of 

 its cells become zygotes, which divide forming 

 spores. Sjierniothajiinium. 



iv. Ovaries dimorphic, some beiug provided with 

 trichogynes and receptive, others devoid of 

 trichogynes and non-receptive ; fertilization of 

 the latter takes place by their fusion either 

 with a receptive ovary, or with a conducting 

 tube given out from it. Zygotes are formed 

 by the non-receptive ovaries only : they un- 

 dergo division forming spores. 



CoraUina, Dudresnaya. 



