^be pilgrims ot tbe lear 153 



diamond. Now each of these diamond-shaped 

 spaces is a distinct through and through division of 

 the liverwort exj^ansion, and the dot in the centre 

 represents the throat or mouth of this portion, being 

 the ojDcning by which so much of the plant as one 

 diamond represents breathes out oxygen and other 

 elenaents of which the space desires to rid itself, and 

 breathes in the carbonic acid gas upon which, in 

 common with other plant life, it feeds. In fact, this 

 dot, which to the unaided eye appears to be merely 

 ornamental, under the magnifying glass reveals itself 

 as a tubular orifice, a ventilating chimne}^ Having 

 investigated the under surface, with its spun-glass 

 hairs serving as roots for mooring, not for nourish- 

 ing this plant, and the diversified upper surface with 

 its air holes, let us make a crosswise section, and 

 magnifjdng it many diameters we shall see that upon 

 the under surface are laid several rows of cells ; each 

 diamond-wise division is elevated at the centre, 

 something like a house roof, the dot, composed of 

 minute cells built into a tube, being at the centre. 

 The surface of the liverwort is composed of a layer 

 of small l3ead-like cells, and between these and the 

 lower cells grow tiny fleshy-branched objects like 

 cactus-plants reduced by a million fold. Dropping 

 the lens we observe tlie liverworts with our* naked 

 eyes, and we see that thej^ liave growing upon the 



