178 BOTANICAL GAZETTE [MARCH 
SEX ORGANS © 
Antheridia appear in about forty days and the points made in the 
case of Lygodium may be repeated here: The first wall is not always 
flat; instances are occasionally found of several cells in the stalk; 
and the sperm number (156) is large. The archegonia appear about 
ten days later, and have two neck canal nuclei, as do those in 
Lygodium. 
Summary 
SPORE COATS 
The spores of Aneimia and of Lygodium have three distinct 
coats. ‘The exine is formed first, and as it broadens its composition 
changes from cellulose, so that with safranin it stains red, and then 
red and yellow. The change may be from cellulose to suberin, 
which stains red, and then to suberin and pectin, as pectin stains 
yellow. The exine of Aneimia hirsuta has ridges on the outer 
surface. 
The intine is the second coat formed, and is the one which covers 
the filament when it emerges from the spore. It remains a delicate 
cellulose wall. 
The epispore is the last to form, and in both Aneimia and Lygo- 
dium is produced by the activity of the tapetal protoplasm. In 
Lygodium granules appear in the protoplasm, increase in size, and 
adhere to the exine. In Aneimia hirsuta spines are formed on the 
ridges of the exine. The protoplasm forms a thin sheet over these 
projections and over the intervening surface of the exine. 
DEVELOPMENT OF THE THALLUS 
The first wall of the spore does not separate the rhizoid and first 
prothallial cell, but the spore contents divide into two cells of unequal 
size, from the smaller of which the rhizoid is produced. 
The apical cell of Lygodium is terminal, appears early, and is 
remarkably persistent. In Aneimia it appears later and is lateral. 
The lobes of the heart-shaped thallus are at first unequal. In 
Aneimia hirsuta this inequality is permanent, but in Aneimia 
Phyllitidis and in Lygodium the lobes become later of the same 
size. 
