CURRENT LITERATURE. 355
strains of the common castor bean {Ricinus communis). The paper is of great interest because it calls attention to the fact that the plant is very favorable material for genetical work. There is a large number of contrast- ing and easily recognizable characters, such as color of stem, foliage, and seed coats ; presence or absence of glaucescence ; dehiscent or indehis cent capsules ; height of plant ; size and compactness of fruiting spike ; time of maturity ; size and shape of seeds ; oil and "acid" content of seeds, etc. The ordinary Indian field presents a hopeless mixture of these characters. Since the plant is monoecious, and the staminate and carpellate flowers are segre- gated in the inflorescence, it is quite easy to conduct controlled pollination experiments. Ricinus should prove very useful for demonstrating to college classes the outstanding facts of inheritance.
Winfield Dudgeon.
Hepaticae
Campbell, D. H. Studies in some East Indian Hepaticae. (Calo- bryum Blumei). Annals of Botany, Jan. 1920.
The writer describes the structure and development of the curious liver- wort Calobryum Blumei. The plant has a much branching prostrate stem like a rhizome without rhizoids which gives rise to erect aerial leafy shoots sym- podially. The leaves are arranged radially in three rows, though one of the rows has often smaller leaves. The leaves are thicker at the base than higher up. The stem grows by means of a tetrahedral apical cell, and it has a large celled cortex and a central cylinder with narrow and elongated cells. Mucilage hairs are present in almost all parts of the plant. Antheridia and archegonia occur separately in clusters and are surrounded bj< large leaves. Development of both is very variable. That of the antheridium is as a rule astonishingly like the development of the archegonium. The stalk of the antheridium consists of four rows of cells and the structure of the latter is like that of other liverworts. The development of the sperms is as usual in liverworts. The apical cell is used up in the formation of the archegonia. The venter is formed of two layers of cells in the mature archegonium, and the neck consists of four rows of cells. The conclusion is drawn that the male and the female organs are homologous. The development of the embryo, so far as seen, was like that in the other Jungermanniales. There is a long seta, and an elongated capsule with a single layer of cells forming its wall and a beak at the apex. Dehiscence by a long slit along one side. Elaters with a double spiral. There is a massive calyptra.
The conclusion is that the separation of Calobryum along with Haplomitr- ium into a family, the Calobryaceae, is entirely justified. The distribution of the genus shows that it was more generally distributed in former times.
S. R. K.
Mosses
Brown, Mabel M. The development of the gametophyte and the
distribution of sexual characters in Eunaria hygrometrica. Am. Jour.
Bot. 6: 387-400. pi. 1. 1919.
Conflicting statements have been made in the literature about the distri- bution of sex organs in this moss. Many have claimed that it is strictly
