. A text-book of botany for secondary schools. Botany. HORSETAILS AND CLUB-MOSSES 203 as are the gametophytes (prothallia) of ferns and equi- setums, are subterranean tuberous bodies with no chloro- phyll, on which the antheridia and archegonia appear (Fig. 194). In some forms of Lycopodium the tuberous prothal- lium develops an aerial portion that is green and bears the sex-organs. This strange subterranean and saprophytic prothallium is in marked contrast with the prothallia of ferns in its habits and appearance.* 118. Selaginella.— The Selaginella forms are much more numer- ous than the Lyc
. A text-book of botany for secondary schools. Botany. HORSETAILS AND CLUB-MOSSES 203 as are the gametophytes (prothallia) of ferns and equi- setums, are subterranean tuberous bodies with no chloro- phyll, on which the antheridia and archegonia appear (Fig. 194). In some forms of Lycopodium the tuberous prothal- lium develops an aerial portion that is green and bears the sex-organs. This strange subterranean and saprophytic prothallium is in marked contrast with the prothallia of ferns in its habits and appearance.* 118. Selaginella.— The Selaginella forms are much more numer- ous than the Lyco- podium forms, being especially abundant in the tropics, and are often called the little club-mosses on ac- count of their smaller size and more delicate texture. It is these forms that are com- mon in greenhouses as decorative plants. There are often no strobili very distinct from the leafy stem, the solitary sporangia occurring in the axils of the upper leaves (Fig. 195). The most important fact in connection with Selaginella is that all the sporangia in a strobilus do not produce the * The gametophytes of Lycopodium are so rarely found that it is not expected that they will be seen by the Fig. 195.—Branch oi Selaginella bearing 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
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