THE DEVELOPMENT OF THE GAMETOPHYTE AND THE DISTRIBUTION OF SEXUAL CHARACTERS INFUNARIA HYGROMETRICA(L.) SCHREB

The conflicting statements published concerning the sexual conditions in Funaria hygrometrica suggested the problem of determining by experimental methods the range of possibilities in the distribution of sex organs in this species. The reproductive organs of the Bryophytes were first clearly recognized as such by Hedwig (I782). He designated the sexual conditions found in the mosses, by analogy with those of the higher plants, as hermaphroditic, monoecious, and dioecious. This classification has been retained until the present time with the addition of several new terms. Schimper (i86o, P. I3) added the term polygamy, applicable to that condition in which the male and female organs of a moss may be borne on the same plant or on different ones. Lindberg (I882) characterized those hermaphroditic species in which the archegonia are scattered among the antheridia and the entire group is enclosed by bracts as synoicous; he gave the designation paroicous to those in which the archegonia are isolated at the apex of an axis and the antheridia are borne in the axils of the leaves. He applied the term autoicous to monoecious mosses in which the sex organs are borne on separate branches of the same plant. He recognized four conditions of autoicism known as cladautoicism, rhizoautoicism, gonoautoicism, and pseudoautoicism. Combinations of synoicism, paroicism, and autoicism have been observed in some species. Such a combination is designated as heteroicism. When, within a species, the condition of dioecism is combined with any of those above mentioned, such a moss is said to be polyoicous. Polyoicism was early known as polygamy. Limpricht (I890) and Ruhland (I909) use the same terms but group them in a slightly different way in their classification. Physiologically there are but two categories of first importance: monoecism, in which the spores, protonemata, and leafy axes (gametophores) are bisexual in their potentialities; and dioecism, the spores, protonemata, and leafy axes being strictly unisexual. In the Bryophytes these terms apply to the gametophyte, whereas in the Spermatophytes the same terms are applied to the sporophyte. Blakeslee (I906) proposed the substitution of the terms homothallic and heterothallic respectively for monoecious and dioecious when used in connection with the gametophyte. There is some confusion in the literature as to what constitutes dioecism 387