A. Henfrey on the Higher Cryptogamous Plants. 29 
large spores are found in great numbers, not merely four ina 
Sporangium as in the Lycopodiacew. The development of the 
Spores was little known until the publication of an essay on the 
subject in 1848, by Dr. C. Miiller,* forming a sequel to his re- 
searches on the Lycopodiaceee. Here, as in the other case, his 
observations on the earlier stages were imperfect ; but he indica- 
ted the existence of the structures which have since been recog- 
nized as the so-called ovules; as also did Mr. Valentinet in his 
essay on Pilularia. 
‘In his essay Dr. C. Miiller compares the complete large spore, 
as discharged from the sporangium, with the ovule of flowering 
plants; and he describes it asa globular sac enclosed by three 
coats, which he names the primine, secundine, and the nucleus. 
The outermost coat, or primine, is stated to be composed of a 
thick cellular membrane exhibiting a raised network of lines, 
which give it the aspect of acellular structure, but are-in reality 
aualogous to the markings on pollen-grains. The outer surface 
exhibits the lines indicating the tetrahedral arrangement of the 
Spores in the parent cell, as in Sedaginella, and it is at the point 
of intersection of these that the membrane gives way in germina- 
tion. The next coat, or secundine, is another simple membrane 
lining the first. The nucleus is a coat composed of delicate par- 
enchymatous cells, but among these are found groups of a pecu- 
liar character. These are described as consisting of a large cell 
divided by two septa crossing each other at right angles, project- 
Ing from the general surface, being either oval in the general out- 
line, or having four indentations opposite the cross septa, so as to 
Sive the appearance of the structure being composed of four spher- 
leal cells. The cells surrou nding them are of irregular form, dif- 
ferent from the generally six-sided cells of the rest of the nucleus. 
any of these groups occur on the nucleus, always at the surface 
of the coat where the primine and secundine afterwards give way, 
Scattered without apparent order over it, but one always near the 
Point of the opening. ‘To these structures Dr. Miller did not 
attribute any important function, explaining them merely as pro- 
duced by peculiar thickenings of the tissues to protect the pro- 
embryo during germination. The contents of the nucleus were 
Stated to resemble those of the cavity of the spore of Selanginella, 
In these contents, which become dense and mucilaginous, a 
Sree cell is developed near the ppper part of the cavity; this is 
the rudiment of the embryo, and by cell-multiplication becomes 
@ cellular mass, which soon begins to exhibit growth in two direc- 
Hons, producing the first leaf and the first rootlet, projecting from 
4 lateral cellular mass, which the author calls the “reservoir 0 
i ‘toatttiate Zeitung, April and May, : 848; Annals of Nat. bape pea ser. vol. 
