CURREY, ON THE HIGHER CRYPTOGAMIA. 71 
the spores. In these orders species nearly allied to one another are 
partly moneecious and partly dicecious. Certain species amongst the 
Chare, Muscinee, the Ferns, and the Equiseta,* produce both kinds of 
sexual organs, archegonia and antheridia, upon the same individual of 
the generation preceding impregnation: the latter are always produced 
before the former. In other Characeze, Muscinex, and Equiseta, the 
male and female sexual organs are distributed upon different individuals 
—a separation which is very complete in certain species of mosses, and 
not in others. The spores from which, in the Characee, Muscinee, and 
Equiseta, dizvious prothallia are developed, exhibit no indication of the 
sex of the individual to be produced from them. But there is often a 
marked difference in the complete form between the male and female 
individuals: the former are much smaller than the latter; they are 
dwarfish, Extreme instances of this are to found, amongst mosses, in 
Dicranum undulatum and Hypnum lutescens. In the Equiseta also the 
male prothallia are always smaller than the females. 
Lastly, the reproductive cells of the Rhizocarpee, Lsoetes, and Selagi- 
nella exhibit, according to their sex, the most remarkable differences in 
their mode of development, size, and form, so long as they continue in 
vital connexion with the organism belonging to the generation following 
impregnation. In the Conifere the reproductive cells differ in their 
origin and formation but little from those of phenogams; they differ 
only in the nature of the vegetative growth subsequent to their formation 
—which growth in the Coniferz is in a high degree independent—in the 
formation of the row of cells in the interior of the pollen-grain, as well as 
in the formation of the endosperm, and of the corpuscula in the interior 
of the embryo-sac. 
There are so many essential points of agreement between the Conifere 
and the phzenogams, that it is more to the point to get rid of the marked 
differences in their respective processes of embryo-formation, than to 
indicate in what they agree. One of these differences is the cell-forma- 
tion inside the pollen-grain, but the principal one is the development of 
the endosperm and of the corpuscula, a process exactly analogous to the 
formation of the prothallia and archegonia of the vascular cryptogams, 
and which is entirely wanting in the phenogams. The whole series of 
developmental processes which occur in the Conifere between the filling 
of the embryo-sac with the cellular tissue of the endosperm and the pro- 
duction of the germinal vesicles in the corpuscula, is entirely passed over 
in the phenogams. Here the germinal vesicles are formed immediately 
in the embryo-sac. In the phenogams there is no vital phenomenon 
analogous to the development of the prothallia and of the endosperm of 
gymnosperns, just as in the cryptogams and the Conifer there is no ana- 
logue to the endosperm-formation which takes place in so many phenogams 
after the arrival of the impregnating organ at the embryo-sac. The 
breaking up of the pro-embryo of the Coniferee into a number of inde- 
pendent suspensors is a phenomenon of the most peculiar kind, to which 
nothing amongst the vascular plants bears any resemblance,f and to 
which the division of the spore (i. e., the mother-cell of the oospores) of 
* The greater number of the Charz and Muscinezx, a few only of the 
Equiseta, and all the known forms of Ferns and Ophioglossex. 
} The formation of the pro-embryo of Loranthus Europeus out of four 
longitudinal rows of cells may be looked upon as a slight indication of 
this. One only of these cells, the terminal cell, becomes transformed 
into an embryonic globule. (Hoffmeister, in‘ Abh, Kon. Sachs. Ges, d. 
Wiss.,’ vi, 543.) 
