776 CELL-DIVISION.—GEMMATION OR BUDDING. 
1131), by which the plant is increased in length ; or on the side 
of the primary cell when branches are produced, as in some 
Conferve (jig. 1132), in the fibrilliform cells of Fungi and 
Lichens, and in other cases, probably, much more frequently 
than is commonly supposed. The mode in which this budding 
occurs may be thus described. At a certain point the proto- 
plasm or primordial utricle appears to acquire a special develop- 
ment, for it is seen to bulge out, carrying the cellulose wall of 
the cell before it, by which a little prominence is produced 
externally (fig. 1132, b) ; this continues to elongate until it forms 
a tubular projection, c, on the side of the primary cell. The cavity 
of this projection is at first continuous with that of the cell from 
whence it sprung, but after the projection has acquired a certain 
definite size, its protoplasm becomes constricted at the point of 
contact with the primary cell, d, and ultimately a cellulose par- 
tition forms between them, as in the ordinary process of cell- 
division. This process of cell-division is usually termed gemmation 
or budding. In some cases, as in the formation of the fibrilliform 
cells of Fungi and Lichens, no partitions are formed, but all 
the branches communicate with each other (jig. 48). 
b. Cell-division with absorption of the walls of the parent celi, 
and the setting free of the new cells.—The pollen cells of all 
Fic. 11388. Fre. 1134: 
89 @@ 
c d 
Fig. 1133. a. Cylindrical cell from which are formed the parent cells of the 
spores of Marchantia polymorpha. p. Protoplasm of the parent cells. 6. 
The same cell converted into a string of cells. c. Oneof the parent cells 
isolated. d. The four sporesfree. (After Henfrey. )——/%g. 1134. For- 
mation of zoospores in Achlya, A. Zoosporangium, still closed. B, The 
same burst, with the discharged zoospores. (After Carpenter.) 
Flowering Plants, and the spores of the higher Flowerless Plants, 
are formed by this process, which only occurs in connexion with 
the organs of reproduction. The manner in which it commonly 
