TYPES OF CRYPTOGAMS; THALLOPHYTES 251 
can be detected. After making the 
microscopic examination which follows, 
note what correspondence of structure B 
with color has been observed. Cut very 
thin sections through fruiting tips from 
different plants, keeping those from each 
plant separate. Be sure that some of 
the cuts pass through the conceptacle as 
near the middle as possible. 
Examine with a power of about sixty 
diameters sections from different fronds, 
searching for one kind containing rather 
large egg-shaped cells and another con- 
taining bundles of numerous smaller yy, 194 —Rockweed rician: 
sac-shaped cells. With a power of 200 4 antheridia borne on branch- 
diameters study the details of the sec- _ ing hairs, x 160; B, anthero- 
tions. Note the character of the cells 7°18 from same, * 380. 
forming the surface of the frond, those 
of the inner structure, and those limit- 
ing the cavity of the conceptacle. Ina 
conceptacle cut through the middle note 
the form of the orifice. Examine the 
slender hairs or filaments ( paraphyses) 
which, arising at right angles, line the 
walls of the conceptacle. 
294. Oodgonia and Antheridia. — In 
conceptacles containing egg-shaped cells 
(odgonia) note the form, 
mode of attachment (ses- 
sile or stalked), and dif- 
ferent stages of develop- 
ment. At maturity the 
contents are divided, 
forming eight odspheres; 
but not all can be seen Fic. 185.— Rockweed (Fucus). 
at once, some bein g be- A, odgonium, its contents dividing into eight odspheres, 
x 160; B, an odsphere, escaped, surrounded by an 
neath the others. therozoids, x 160. 
