1917] CHAMBERLAIN— LYCOPODIUM 53 



i together with the results of DeBary, who had described early 



stages of L. inundatum from cultures, made it possible to make a 

 general outline of the development from the germination of the 

 spore up to the adult pro thallium with sporelings attached. 



i Beck sowed the spores of various species under various condi- 



tions, but L. inundatum was the only one to germinate and the pro- 

 thallia did not get beyond the 10-cell stage. He asserted that 

 after 2 years the spores of L. clavatum showed chlorophyll and 

 looked as if they were about to germinate, but no cell division 



occurred. 



Fankhouser's DaDer aDDeared, i men have made 



contributions to our knowledge of these peculiar prothallia. In 



Treu 



Javanese species. In 



1885, Bruchmann (8) began his patient and persistent researches 

 upon the difficult temperate species with subterranean prothallia 

 which had baffled all previous investigators; and in 1887, Goebel 

 (10) found prothallia of L. inundatum, so that, with the stages 

 secured by DeBary, he was able to give a connected account of 

 this species. 



Treub began his series with an investigation of L. cernuum. 

 He germinated the spores of this familiar tropical species and some 

 of the prothallia reached the early antheridium stage before the} 

 died. However, he found abundant material growing wild, and 

 so had a complete series from the germination of the spore to the 

 adult prothallium with embryos and older sporelings. 



The prothallia are green and grow on the surface of the sub- 

 stratum, the largest reaching a height of 2 mm. When the spore 

 germinates, a more or less spherical body is formed, about 8 or 10 



cells in diameter. 



which Treub 



the "primary tubercle," an alga-like filament then develops, at 



divid 



cylindrical body is formed more 



primary 



The 



tip of the cylindrical portion is profusely branched, and at the base 



and 



The 



embryogeny is particularly interesting, since the fertilized egg does 





