16 THE UNCOILING FRONDS. 
discoveries.” And again: “The production of perfect 
germinating seeds contained in capsules.... is as 
clear in ferns as in mosses though nothing is certainly 
known of their stigmas any more than of their anthers. 
We are nevertheless content to plead ignorance on the 
subject and to presume by analogy that such parts exist, 
rather than to assume the idea of some other mode of 
impregnation, hitherto unknown, which would be going 
contrary to the first principles of Philosophy.” 
What really happens in the generation of new ferns, 
and the way it is accomplished, is as follows. About 
mid-summer, there appear upon the underside of the 
fronds of most species, numerous small dots very reg- 
ular in size and shape. These are the “ fruit-dots” or 
sort (singular, sorws) and under a simple lens are seen 
to be collections of tiny stalked globes. 
In the majority of cases, each sorus is 
a covered with a membrane called an 
HR 2 until nearly ripe. In these globes, 
iN + collectively called sporangia, are pro- 
“duced many smaller one-celled bodies 
known as spores. At maturity these 
keer esi “spore-cases’”’ open, and with a snap 
scatter the spores upon the wind. Ordinarily they 
germinate soon after leaving the capsules if a suitable sit- 
uation is encountered, but failing in this, some species 
are able to retain their vitality for nearly twenty years. 
Spores must not be mistaken for seeds, however. In no 
way do they resemble them except that they may serve 
to carry the species through a resting stage, as seeds do. 
When a seed is planted, a plant like the parent will 
come up, but a germinating spore does not give rise toa 
