1898] BRIEFER ARTICLES 281 
othe gum-bearing tissue of Canna a schizogenous origin. It cer- 
uinly presents an aspect very suggestive of gum secreting cavities. 
The fact is, however, that very little of the gum makes its first 
ippearance upon the cell walls. It forms in thick layers in the cell 
interior, and, gradually condensing, forces the cytoplasm and its con- 
nts into the center. Little by little this alteration extends into 
wighboring cells. The condensation of the protoplasm is constantly 
increased in the central cells, whose walls seem to thicken as the 
membrane increases in volume. At a certain point the protoplasm 
ad the thickened membrane surrounding it blend into a mucilagi- 
‘ousmass. This transformation may appear at first either in a single 
ell, or in a little group of cells always placed near the center of the 
In no case did I notice any such intercellular space sur: 
roanding the secreting cells as occurs in the ordinary method of for- 
"ation of secreting canals. The gum of Canna is formed in a lysigen- 
ws Way, just as are those of the acacias, of fruit trees, and especially 
of the aralias. As gelatinization continues the gum-bearing region 
spreads, and tends to form pockets of varying form and dimension. 
Formations of the same kind may occur in the fibrovascular bun- 
Gelatinization is produced first in the wood and woody paren- 
the i he then penetrates into the vessels, probably by —— 
bende i n ’ vessels become gelatinized in their turn, and the whole 
There ae into a gum bearing cavity. ae 
‘tereighbori, also be noted the extreme diminution of amidon i 
"kg ood, which immediately succeeds the mucilaginous mod! 
Thave studied the same point ina large number of stems of other 
taken from dried specimens in the Museum d'Histony 
* and from the Ecole supérieur de Pharmacie de Paris. ip 
Lutz, Parts, 
Aone 
% ie found an analogous formation.— M. L. 
