OEGANS OF BEPKODrCTION. 383 



Fig. 834. Fig. 835. 



nisj?!=P:. jRHiin 



Fig. 838. 



Fig. 834. Section of the 

 frond of Rhynchococcui 

 coronopifolius, with te- 

 traspores immersed in 

 its substance. After 



Henfrey. Fig. 835. 



Section of a concep- 

 tacle of Eildenbrandtia 

 sanguinea, containing 

 tetraspores. After 



Henfrey. Fig. 836. 



Stlchidium of Dasya 

 Kntzingiana, contain- 

 ing tetraspores. After 



Henfrey. Fig. 837. 



Two favellcB of Callithamnion tetragonum, containing spores. 



Fig. 838. Ceramidium of Bonnemais(mia asparagoides, 



containing spores, and terminated by a pore. 



Fig. 836. 



the cells of articulated threads, situated commonly in the concep- 

 tacles. They consist of at least two coats of a somewhat gelatinous 

 nature, enclosing a dense clustered granular mass. Whether 

 these spores are gemm<s or true generative spores has not yet 

 been determined (see Tetraspores). 



3. The Antheridia. — But little is known of the structure of 

 the antheridia of this sub-order of Algse. They are collections 

 of little cells of various forms, and variously arranged, in each 

 of which a peculiar body, called a spermatozoid or antherozoid, 

 is ultimately formed ; these do not, however, exhibit the spon- 

 taneous motion as is usually the case with ordinary antherozoids. 

 According to Berkley, "the spermatozoids vary a little in shape. 

 Derb^s and Solier figure many of them with a delicate appendage ; 

 but Thiu-et has in vain sought for such an appearance. There 

 can, however, be little doubt that they are truly impregnatory 

 organs. The flagelliform appendage cannot certainly be con- 

 sidered as essential to their functions." 



Zoospores have not at present been found in this division of 

 the Algae. 



3. Melanos])ore<8, Fncoidea, or Brown-coloured Alga. — The 

 sexual natiu'e of these Algse is generally considered esta,blished, 



