80 
Druce^ on Confervoidea. 
are never sporangia^ altliougli those unimpregnated may 
remain in the condition of encysted gonidia^ or^ under 
favorable circumstances^ subdivide at once into zoospores. 
Thirdly, that the trae spores are fecundated by antherozoids 
developed in capsules, at first themselves motile, and after- 
wards either inside the parent cell, as in Spirogyra, or outside, 
as generally in CEdogonium, freeing their contents either by 
the rupture of the cell-wall or the dehiscence of a definite 
lid. Fourthly, that the antheridia may become encysted 
in the autumn, as well as the resting spores, and impregna- 
tion take place either before the formation of the envelopes 
of the spore in the autumn, or in the spring, when these are 
ruptured. (See Plate YI.) 
In conclusion, I am conscious how little I have performed 
towards the fulfilment of my programme at the outset, and 
how easily I may be condemned upon my own premises; but 
I proposed it to myself rather as an indication towards right 
investigation, than with any hope of completing it myself on 
the present occasion. Finally, I lay claim to very little novelty 
in the foregoing observations, my object having been rather 
the attempt to consolidate and connect together facts already 
known, than to proclaim a new thing ; and I do desire to call 
the attention of microscopists who have no special study, to 
these lowly organisms, not merely that it is a favorable 
field for research, off'ering the charm of novelty and ever- 
changing beauty, but also because the study is full of the 
highest physiological interest; for from unicellular organisms 
is there the greatest chance of discovering the great funda- 
mental, and as yet hidden, laws of life. 
