1912| LEWIS—ALTERNATION IN FLORIDEAE 239 
nion, and Cystoclonium are found. In other cases, as Chondrus 
and Agardhiella, growth of the sporelings was so slow that they 
became covered and killed by the growth of exotic spores. In still 
others, the sporelings failed to become established, even the short 
time in which they were under laboratory conditions being sufhi- 
cient to cause them to cease growing. Strange to say, some of 
these, as Ceramium rubrum and Chondria tenuissima, seem to be 
quite hardy, and are abundant and luxuriant in Situations similar 
to those in which the shells were planted. Still others, including 
Champia and Lomentaria, were early discarded because of the 
frequency with which these species establish themselves on any 
suitable solid support. 
Record of — 
I. Agardhiella tenera.—Tetraspores and carpospores sown July 
18, 1910, transferred to Spindle Ledge July 19. Shells collected 
August 10, and found to be much overgrown with foreign algae. 
Search revealed hundreds of small sterile Agardhiella plants, of 
which the average length was 0.5 mm. Some were of good color 
and apparently vigorous, but the great majority had ceased grow- 
ing and were beginning to become discolored. The most interest- 
ing point about this culture was the fact that the sporelings from _ 
carpospores and tetraspores were of exactly the same size and 
conformation. 
II. Grinnellia americana.—Treatment like that of Agardhiella. 
Hundreds of sterile specimens were found, 3-4 mm. long, vigorous 
and of good color. The fact that the amount of growth in 24 days 
at the height of the growing season was so slight would seem to 
indicate that this species, like the preceding one, is biennial, the 
-sporelings of one summer reaching maturity the next year. 
III. Polysiphonia violacea.—Tetraspores and carpospores sown 
July 18, 1911, transferred to piles at end of Fay Wharf July 20, 
collected August 14. The shells sown with tetraspores were acci- 
dentally destroyed before being collected. On examination, the 
shells sown with carpospores were found to be pretty thickly over- 
grown with Polysiphonia variegata, mostly sexual. Scattered 
among these plants, however, were 29 individuals of P. violacea, 
varying in length from 1.0 to 3.1 cm. The color of all was darker 
