THE PROTHALLUS OP FERN?, ' . \ '. <ioi 



liver-wort or Marchantia it is called the Marchantia-like 

 growth. 



The botanists of some two hundred years ago (such 

 as John Ray [1670], who ridiculed a botanical friend for 

 trying to catch fern seed on a sheet spread out on Mid- 

 summer's Night, when the spore-cases have not yet come 

 into existence) raised these flat green growths from spores 

 sown on damp mould, and were at first puzzled by getting 



A 



FIG. 8. A. Underside of the prothallus of a fern showing rh., root- 

 filaments ; an., sperm-sacs or antheridia, and ar., .egg-pits or 

 archegonia. Magnified about four times linear. B. A prothallus 

 showing the young fern (b.) springing from it ; w., root-axis of the 

 young fern ; rh., root-filaments of the prothallus. 



no further result. It, at any rate, was clear that there was 

 some excuse for the rustics who found no obvious connection 

 between the contents of the spore-cases and the production 

 of a new generation of ferns, for the thing which grew 

 from the spore was not a fern ! But then the observations 

 were carried further, and it was shown first in 1715, 

 and again later in 1785, that from the substance of the 

 flat green expansion or prothallus, after an interval of time 



