. The cyclopædia of anatomy and physiology. Anatomy; Physiology; Zoology. The same, containing four vesicular nuclei, each cell the nucleus disappears, and is re- placed by two others, between which a per- pendicular septum is formed. From a repeti- tion of the same process, there results a cylindrical body consisting of a series of four cells, the fully formed elater. 64. No sooner are the spores of the upper part of the capsule ripe, than it splits into two valves; dehiscence commences at the apex, leaving, as it proceeds, the columella with the loosely attached spores and elaters. 65. Junge
. The cyclopædia of anatomy and physiology. Anatomy; Physiology; Zoology. The same, containing four vesicular nuclei, each cell the nucleus disappears, and is re- placed by two others, between which a per- pendicular septum is formed. From a repeti- tion of the same process, there results a cylindrical body consisting of a series of four cells, the fully formed elater. 64. No sooner are the spores of the upper part of the capsule ripe, than it splits into two valves; dehiscence commences at the apex, leaving, as it proceeds, the columella with the loosely attached spores and elaters. 65. Jungermannicefrondosee:—From Antho- ceros we pass to a group of plants, which, while they resemble it in their mode of growth, differ from it considerably in the form of their antheridia and archegonia, and still more in that of the organs in which they are contained. Here as in Anthoceros we follow the descrip- tion of Hofmeister (Pellia epiphylla).* 66. First period.—Germination of the spores. —The spore is an ovoid cell, divided into four by three transverse septa, and enclosed in a finely granular external membrane. Of the four cavities, one of the terminal ones dis- tinguishes itself from the rest by the small quantity of chorophylle which it contains. This cavity, or rather the cell which it represents, develops in germination, to the first hair-like roots; while the others, by successive divisions by septa in the direction of the long axis of the spore, form the rudi- mentary flattened stem of the young plant. 67. The antheridia.— The rudiments of the antheridia make their appearance as club- shaped projections of the upper surface of the young spring shoots. Each such projec- tion originates from a single cell of the super- ficial layer by a mode of division which cor- *. ». i . i i *» l soon place themselves in such a manner, that each would occupy one angle of a regular tetrahedron contained in the parent cell. Up MWTO „. w. „ „ .„„. _ to this point th
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