77 



TETRASPORE LIKE STRUCTURES ON SEXUAL PLAITE . 



As stated a"bove, one individual lias "been found v/liich 

 produced normal antheridia on the niajority of its f ilaiaents, 

 but v/}iicii produced on a considerable niunber of filauents 

 structures resembling the sori of tetraspores . As this case 

 is of considerable theoretical interest at the present 

 time, I sliall nov; give sorae of the details of the structure 

 of this plant. 



The portion of the plant berring antheridia './asper- 

 foctly norinal in appearance. The cells v/ere of the usual 



size and siiape, and bore antheridia of the normal t^^pe in 

 abundance. The munber of chromosomes appearing in Liitoses 

 in the antheridial fila::ients v/as found to be about seven 

 (the reduced nxnaber, characteristic of the ga-metophyte. 

 Mitosis has a.s yet been seen in only a single nucleus of 

 the portion of the plant bearing the tetraspore-like struc- 

 tures. In this case, in the dividing nucleus of the stalk 

 cell, the number of cliromosomes was seen to be seven (see 

 fig. 14^. 



The branches bearing tetraspore-like structures are 

 of the saxae ti^e as those of the normal tetrasporic plant, 

 but are composed of cells tliat are on an average a good ^«- 

 deal smaller. 



