422 baker's north YORKSHIRE. 
It has hitherto escaped detection in North Yorkshire, but 
should be looked for in the dry limestones of that district. 
In 1753 Linneus introduced his artificial classification 
of plants. By it all flowering plants are arranged into 
23 classes by the number and position of the stamens and 
pistils, the reproductive organs of the flowers. Linneus 
named his 24th class Cry ptogam la, in which was included 
all non or hidden flowering plants, such as Ferns, Mosses, 
Fresh water weeds and Sea-weeds, Lichens and Fungi. 
Cryptogamic plants far exceed in number the flowering or 
Phanerogamic plants of the British Islands. By the more 
natural arrangement these numerous forms of vegetable 
life have been divided into three main groups. 
The ist group. — ThaM'ophyta. The vegetative body in 
these plants is a thallus or simple grouping of cells, without 
separation into stem, leaf, and root ; or if at all in a 
very rudimentary condition. This section contains the Sea- 
weeds and fresh-water Algae, the Lichens and the Fungi. 
The 2nd group. — Bryophyta. The plants forming this 
group are the Urn Mosses (Muscineae), the Sphagnums or 
Bog Mosses (Sphagnaceae), and the Liver-worts or Scale 
Mosses (Hepaticae). 
The 3rd group— Pteridophyta (Vascular cryptograms) 
contains the Ferns, Horsetails (Equisetums) and the Club 
Mosses (Lycopodiums) and are included with the Phanero- 
gams or flowering plants in Baker's ''North Yorkshire." 
The artificial system of classification adopted by Linneus 
was in some measure applied to Mosses by early Continental 
authors; thus Hedwig's works (1782 to 1801) and Bridel's 
works (1798 to 1826). The chief character b}- which the 
mosses were arranged into genera was by the number and 
arrangement of teeth or peristone around the mouth of the 
urn-like capsule. This method was to a great extent 
followed by Hooker and Taylor in their Muscologia 
Britanica," (181 8, a second edition, 1827) which was a 
