Cryptogamia Cryp`to·ga"mi·a noun ;
plural Cryptogamiæ (-...). [ New Latin , from Greek
krypto`s hidden, secret +
ga`mos marriage.]
(Botany) The series or division of flowerless plants, or those never having true stamens and pistils, but propagated by spores of various kinds. » The subdivisions have been variously arranged. The following arrangement recognizes four classes: -- I.
Pteridophyta , or
Vascular Acrogens . These include
Ferns ,
Equiseta or Scouring rushes,
Lycopodiaceæ or Club mosses,
Selaginelleæ , and several other smaller orders. Here belonged also the extinct coal plants called
Lepidodendron ,
Sigillaria , and
Calamites . II.
Bryophita , or
Cellular Acrogens . These include
Musci , or Mosses,
Hepaticæ , or Scale mosses and Liverworts, and possibly
Characeæ , the Stoneworts. III.
Algæ , which are divided into
Florideæ , the Red Seaweeds, and the orders
Dictyoteæ ,
Oösporeæ ,
Zoösporeæ ,
Conjugatæ ,
Diatomaceæ , and
Cryptophyceæ . IV.
Fungi . The molds, mildews, mushrooms, puffballs, etc., which are variously grouped into several subclasses and many orders. The
Lichenes or Lichens are now considered to be of a mixed nature, each plant partly a Fungus and partly an Alga.
Crystallization Crys`tal·li·za"tion (krĭs`t
a l*lĭ*zā"shŭn)
noun [ Confer French
cristallization .]
1. (Chem. & Min.) The act or process by which a substance in solidifying assumes the form and structure of a crystal, or becomes crystallized. 2. The body formed by crystallizing; as, silver on precipitation forms arborescent crystallizations . » The systems of crystallization are the several classes to which the forms are mathematically referable. They are most simply described according to the relative lengths and inclinations of certain assumed lines called axes; but the real distinction is the degree of symmetry characterizing them. 1.
The Isometric, or Monometric, system has the axes all equal, as in the cube, octahedron, etc. 2.
The Tetragonal, or Dimetric, system has a varying vertical axis, while the lateral are equal, as in the right square prism. 3.
The Orthorhombic, or Trimetric, system has the three axes unequal, as in the rectangular and rhombic prism. In this system, the lateral axes are called, respectively,
macrodiagonal and
brachydiagonal . -- The preceding are erect forms, the axes intersecting at right angles. The following are oblique. 4.
The Monoclinic system , having one of the intersections oblique, as in the oblique rhombic prism. In this system, the lateral axes are called respectively,
clinodiagonal and
orthodiagonal . 5.
The Triclinic system , having all the three intersections oblique, as in the oblique rhomboidal prism. There is also: 6.
The Hexagonal system (one division of which is called
Rhombohedral ), in which there are three equal lateral axes, and a vertical axis of variable length, as in the hexagonal prism and the rhombohedron. »
The Diclinic system , sometimes recognized, with two oblique intersections, is only a variety of the
Triclinic .