98 



LECTURE VII. 



show at once that a certain relation exists between the form of the organ in 

 which growth and cell-division are taking place, and the direction, curvature, 

 and general arrangement of the newly arising cell-walls — a relation of which 

 we shall speak more in detail later on, when considering growth in its relation to 

 cell-formation. 



The relations just mentioned are partly or entirely wanting in the develop- 



FlG. 97 —Peziza convexuta. A vertical section tlirougli the 

 whole Fungus (X 20); h Hymenium, i. e. the layer in which the 

 spore-producing asci are situated ; j the tissue body which 

 surrounds the hymenium at the margin (?) like a cup. Fine 

 filaments proceed from the base and penetrate into the soil. 

 B Small portion of hymenium (X 550) ; sh sub-hymenial layer of 

 densely interwoven hyphae ; n—f asci, with spores in various 

 stages of development ; between are thinner filaments— para- 

 physes— containing red granules. 



Fig. 98.— Zoosporangia of Aclüya (X S5o)- 

 A still unopened; B the zoospores are escap- 

 ing; a zoospores just emitted; b membranes 

 left behind, from which the swarming zoo- 

 spores (f) have escaped ; c a lateral bud. 



ment of reproductive cells, such as oospheres, spores, and pollen-grains : for, in the 

 majority of such cases, the formation of new cells appears as if it did not depend 

 upon a mere cutting-through by means of a new partition wall. The cell- 

 formation gives here the impression of being not a mere division into chambers 



