560 
The older fronds are often beset with warts which have nothing to do with 
the fructification, nor do they seem to be undeveloped young branches, for they 
do not show the anatomical differentiation of the latter and must be considered 
as luxuriations of the cortex and may show stratification like this. Sometimes a 
cavity produced apparently by some parasite was found at the bottom of it, having 
its base at the inner limit of the cortex, and partly filled with what seemed to be 
decayed remains of the cells of the host which took a deep blue stain by methylen 
blue. They had an opening at the top of the wart and had been left by the parasite. 
It seems doubtful, however, whether the warts had really been caused by the 
supposed parasite, for in other warts no cavity seemed to be present, and similar 
cavities were found without causing such warts. In other warts the cavity was 
found filled with a granular matter which seemed to be small bacteria. The first 
described cavities have perhaps also been in- 
habited by bacteria which have left them later. 
The bacteria observed were very small; there 
seemed to be cocci and short rods. SCHMITZ has 
described tubercles containing bacteria in several 
other Florideæ (Botan. Zeit. 1892). 
Tee Fig. 5519 s Reproduction. The reproduction of Ahn- 
Ahnfeltia plicata. First origin of nemathecia. 
September. 670 : 1. feltia has been imperfectly known and disputed 
until quite lateiy. From the beginning of the 
ninetienth century, at least, cushions on the frond have been described and 
usually considered as the fructification of the species. LyNGByEe (Tent. 1819, p. 42) 
observed them in spring but did not meet with any spores. C. AGARDH (Spec. alg. 
1822, p. 313) stated that they were composed of articulate filaments and named them 
nemathecia. Kitzinc (Tab. phyc. 19, tab. 66, 1869) thought that the nemathecial 
filaments were transformed into seriate spores, but that has not been confirmed. 
The spores were first described by BurrHam (1893, p. 302) and Schmitz (1894, 
p. 397) who found that the spores are only produced in the end-cells of the nema- 
thecial cell-rows, these cells each giving rise to one monospore. SCHMITZ submitted 
the nemathecia to an anatomical investigation and arrived at the conclusion that 
these bodies were not organs of the Ahnfeltia but that they were parasites, which 
he called Sterrocolax decipiens, growing on the surface of Ahnfeltia and penetrating 
into the cortex of the latter by numerous “Senker”. But this inference was only 
founded on the presence of the said processes and not on the study of the develop- 
ment of the nemathecia or of the “Senker”. Hence ScHmiTzs inference is not 
conclusive, and it would lead to the absurd conclusion that no kind of reproduc- 
tive organs had ever been observed in Ahnfeltia plicata. To elucidate the question 
of the nature of the nemathecia I have examined their development and the ger- 
mination of the spores. The results of my investigations have been published in a 
particular paper (1931) where 1 have also mentioned two smaller papers of GREGORY 
and CHEMIN treating the same question and published shortly before the publication 
