THE SPORE COATS OF SELAGINELLA. 
CONTRIBUTIONS FROM THE HULL BOTANICAL LABORATORY. 
LXXX. 
FLORENCE LYON. 
(WITH PLATES X AND XI) 
Since the development of the modern technique in botany, com- 
paratively little has been done in investigating the mode of formation 
of cell walls or of spore coats, and botanists are still much in the 
dark as to the nature, as well as the morphology, of certain complex 
sttuctures protecting the protoplasm of spores. A recent contribu- 
ton to this subject by Firrrnc* is of special importance, because 
=* result of his study of the development of the spore coats of cer- 
tain species of Selaginella, he advanced a theory that they grow 
quite independently of the protoplasm of the spore, with which during 
the time of their greatest increase in bulk they have no organic con- 
nection except at one point. This, of course, is revolutionary and 
ees at variance with all previous ideas of the growth of membranes; 
= . it is true that protoplasm ‘can act at a distance,” and without 
®rganic connection can build massive structures, the fact is of the 
Sreatest importance. 
“ the time that Frrrrnc’s paper appeared, I was investigating 
aes Phases in the life history of two native species of Selaginella— 
ie S. rupestris. In the main the peculiar phenomena 
ek ed with the formation of the spore coats of the first named 
seemed to agree with those described by Frrtmnc; but the 
dev. 
it — of the spores of S. rupestris differed so completely that 
distj ame a matter of interest to determine whether there were two 
n 
ence Ct types of spore formation in this genus or whether the differ- 
S 
taken ads More apparent than real. The present work was under- 
dite th a view to throwing some light upon this question. The 
€s which all investigators have encountered at every stage 
1 Fr 
Isoetes aoe ° Ss; Bau und Entwickelungsgeschichte der Makrosporen von 
icher Zellm aginella und ihre Bedeutung fiir die Kenntniss des Wachsthums pflanz- 
see) embranen. Bot. Zeitung 58':107-164. 1900. 
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