CARPOPHYTA. 151 
gone, but the actual entrance of the former has not yet 
been seen. After fertilization the protoplasm in the car- 
pogone increases considerably in size, and forms a cellulose 
coat of its own. The cells which support the carpogone 
send out lateral branches, which grow up and closely sur- 
round it, finally covering it entirely (excepting the tricho- 
gyne) with a cellular thick-walled “ pericarp” (B,r). The 
whole mass, including the fertilized carpogone and its in- 
vesting pericarp, constitutes the simplest form of spore- 
fruit (the sporocarp). 
311. The further growth of the spore-fruit takes place 
the next spring by the swelling of the protoplasmic con- 
tents, and the consequent rupture of the pericarp; the 
inner portion divides into several cells, C (the proper fruit- 
spores), which give rise to zodspores closely resembling 
those developed from the vegetative cells. From each 
zodspore a new plant eventually arises. 
Practical Studies.—(a) These little plants occur in fresh-water pools 
as little green masses adhering to leaves, sticks, etc. According to 
Wood, we have probably two species. 
(5) The sexual process and the development of the sexual organs 
occur in May, June, and July. 
Crass I. FiLormwnz (the Red Seaweeds). 
312. The plants of this class, which are almost without 
an exception marine, are among the most beautiful and in- 
teresting members of the vegetable kingdom. All have 
some shade of red or purple which sometimes becomes ex- 
ceedingly rich; while for beauty of outline and delicacy of 
branching they stand unrivalled among plants. 
313. To a great extent they grow in the deep water 
below low-water mark, far beyond the reach of the ordi« 
