. A textbook of botany for colleges and universities ... Botany. 56 MORPHOLOGY Nemalion. — This marine form will serve to illustrate the simpler red algae. It is a branching filament, and probably produces no tetra- spores. Anlheridia. —The antheridia occur in clusters at the ends of short branches (fig. 146), each antheridium being a single cell, which at first contains a single nucleus. This nucleus divides, so that the protoplast of the mature antheridium contains two male nuclei. Physiologically, therefore, the an- theridium contains two sperms, but they are not organ- ized as morpho- logi
. A textbook of botany for colleges and universities ... Botany. 56 MORPHOLOGY Nemalion. — This marine form will serve to illustrate the simpler red algae. It is a branching filament, and probably produces no tetra- spores. Anlheridia. —The antheridia occur in clusters at the ends of short branches (fig. 146), each antheridium being a single cell, which at first contains a single nucleus. This nucleus divides, so that the protoplast of the mature antheridium contains two male nuclei. Physiologically, therefore, the an- theridium contains two sperms, but they are not organ- ized as morpho- logically distinct sperms. This bi- nucleate protoplast is discharged from the antheridium, and not being cili- ate it is carried by water currents to the female _ organ. This non-motile sperm, or sperm complex, is usually called a sperma- tium, but there is Figs. 146-148. — Nemalion: 146, branch showing antheridia no special ad van- forming at the tips; 147, the procarp, consisting of trichogyne fg^gg jjj multiolvinff and carpogoniura (in the latter the male and female nuclei are observed, the former having passed in from the trichogyne); '•"^ names 01 a also shov»ing two other cells with the broad cytoplasmic con- male cell. The nectidns; 148, a cystocarp, showing the carpospores being cut cr^ppjol name was off at the tips of short branches, which have arisen from the fertilized carpogonium. felt to be necessary when motile sperms were called spermatozoids or antherozotds, but the general term sperm can be applied to non-motile as well as to motile male cells. Female sex organ. —The female sex organ of Nemalion illustrates, perhaps in its simplest form, this remarkable structure among the red algae, which usually consists of several cells and is called the procarp. In Nemalion the procarp consists of what may be regarded as two cells. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - colora
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