CULTIVATION'. 
367 
much in habit, chiefly as regards the nature of the roots, 
which are thickened and fleshy, and generally pene- 
trating deeply into firm soil. In their general character 
they present much resemblance to the roots of 
Cycadece, Cyclanthece , and other allied endogens; also in 
venation the remarkable genus Stangeria connects them 
through Dancea with Cycadece ; and their compound 
fronds are represented in the same family through the 
new genus Boicenia. The species of Marattia and 
Angiopteris grow freely in a loamy soil, requiring 
plenty of water. Some species of Angiopteris require 
much space, for although the caudex does not rise 
much above the ground, yet a plant at Kew produced 
fronds that reached the height of twelve feet, spreading 
outwards, forming a diameter of thirty-four feet. The 
species of Dancea and Kaulfussii are, -however, not 
such free growers; they require a moist and high 
temperature. 
I have now gone through a few of the principal genera 
requiring special kinds of treatment ; the next consider- 
ation is good management as regards temperature, 
watering, airing, and keeping free from insects. Much 
depends on the size and nature of the house ; the larger 
it is, the less fluctuations of temperature take place, 
especially in a house of the ordinary construction of 
glass roof and sides, whether lean-to or span. The 
maintenance of a proper condition of the air in plant- 
houses depends much on the nature of the interior 
fittings. White or polished, reflecting and radiating 
surfaces, should be avoided as much as possible, such 
as iron pillars, rafters, spandrels, polished slate or 
smooth stone, iron or stone floors, &c. These kinds of 
material are often introduced in superabundance, for 
