CELLS. SCLEROGEN. 
65 
pores is well shown, A curious point in this section 
is, that cells appearing so truly different in structure, 
should occur so close to each other, and that there 
should be no gradual transition from one to the other. 
In the cells of some plants the deposit takes place in 
concentric layers. In a section of the Snake-wood, 
Brosimum guianensis , a wood not unfrequently used 
in the manufacture of bows for the archer, there are 
many large ligneous cells, in which the deposit has taken 
place in concentric laminae, the pores running through 
them being small and few in number ; and the central 
spot, although of very minute size, is occupied by a mass 
of rich brown resinous matter. These cells have been 
already described, and one of them is represented by 
D, Fig. 4 ; the same kind of tissue is found in the 
cones of the Common Fir, which consist of elongated 
cells, nearly full of deposit. Four of these, divided verti- 
cally, are represented by g, in Fig. 4, and a mass of the 
same in transverse section by H, in the same figure. In 
the old ligneous cells of the bark of the Beech , the con- 
centric deposit is remarkably well seen with scarcely any 
trace of pores, as illustrated by Fig. 49. A singular 
form of laminated deposit, combined with a branched 
condition of the pores or canaliculi, is found in the seed 
of the Star-anise represented in Fig. 50. It is best 
seen in specimens mounted in Canada balsam, and 
when the central cavity and pores of the cell are full of 
air. The laminae are well shown in sections of the 
cells, but the branching of the pores, which are very 
F 
