. A text-book of botany for secondary schools. Botany. ALG^ 127 little fruit (Fig. 119, 5 and C, and Fig. 120). The spores it contains produce the alga plants again. Such a life-history is more complex than any thus far given. During the growing season the tetraspores multiply the plant; and the life-history may be indicated as follows, P designating the ordinary plant body: P—tetraspore—P—tetraspore—P—tetraspore, etc. Such a series, however, does not continue indefinitely; for it is stopped by the coming of an unfavorable period, such a period as winter represents to many plants. In the life-


. A text-book of botany for secondary schools. Botany. ALG^ 127 little fruit (Fig. 119, 5 and C, and Fig. 120). The spores it contains produce the alga plants again. Such a life-history is more complex than any thus far given. During the growing season the tetraspores multiply the plant; and the life-history may be indicated as follows, P designating the ordinary plant body: P—tetraspore—P—tetraspore—P—tetraspore, etc. Such a series, however, does not continue indefinitely; for it is stopped by the coming of an unfavorable period, such a period as winter represents to many plants. In the life-history of our red alga this unfavorable period is bridged by the fruit-like body, just as in the other Algse it is bridged by the heavy-walled oospore. Such. Fig. 119.—Cue of the red Alga;: A, sexual branches, showing antheridia (a), oogonium (o) with its long neck (0 to which are attached two sperms (s); B and C, development of the fruit-like body.—After Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Coulter, John Merle, 1851-1928. New York, D. Appleton


Size: 1276px × 1957px
Photo credit: © The Book Worm / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: ., bookcentury1900, bookdecade1900, booksubjectbotany, bookyear1906