MARcflim] MIYAKE.—GAMETOPHYTES ETC. OFCUNNINGHAMIA. '49 



peculiar free cell-formation proceeding the formation of the per- 

 manent prothallial tissue as reported b\' Lawson^^ in Cryptomeria 

 has not been observed. 



The archegonial initials were observed at the micropjdar 

 end of the prothallium, even before the prothallial tissue was 

 thoroughlv organized. The de- 

 velopment of the archegonia 

 agrees, on the whole, with that 

 has been observed in Taxodium 

 and Cryptomeria. The process 

 is rather rapid and at the end of 

 June the archegonial complex is 

 fully formed (Fig. 8). The number 

 of the archegonia in the complex 

 varies usualh' from 13 to 16, the 

 smaller and larger numbers being 

 sometimes observed. Unlike those 

 of Cryptomeria and Taxodium 

 the archegonial complex has a 

 sterile prothallial tissue at the 

 centre and the archegonia are 

 arranged around it completely 

 enclosing the former (Fig. 9). 

 The archegonia are, in turn, sur- 

 rounded by a common la^-er of 

 jacket-cells. 



The central cell of the vounof archegonium has vacuolated 

 cytoplasm and a nucleus situated close to the neck. The cyto- 

 plasm gradually becomes densely granular, and soon the nucleus 

 undergoes a division (Fig. 10). Of the two nuclei thus formed, 

 the upper one, the ventral canal-nucleus, soon degenerates, and 

 the lower egg-nucleus enlarges rapidh' and comes down towards 

 the centre of the egg (Fig. 11). The division occurs about the 

 3rd of July, and the fertilization takes place about between the 

 3rd and the 5th of July. The only one sperm-cell of the pollen- 



Fig. 10. Division of tlie central 

 cell of archeajoniurn.- — Fig. 11. Mature 

 pcrw — Fig. 12. Fusion of two sexual 

 nuclei.— Fig. 13. The first segmentation- 

 spindle. — Fig. 14. Proeij:bryo. x 145. 



2) 1. c. p. 427 



