404 BOTANICAL GAZETTE [JUNE 
then seen, which gradually increases, and at the same time the 
outline of a stout rod, sometimes bent or irregularly swollen, 
becomes more and more distinct within the spore-wall ( fig. 35). 
The emerging rod elongates with considerable rapidity, until it 
becomes about twice as long as the diameter of the spore. In 
several cases it was then seen to slip out free from the spore 
wall ( fig. 35, #, and, four minutes later, z) which remains for a 
time as an empty shell, but gradually dissolves and disappears. 
More commonly, however, the emerging rod does not escape 
from the spore wall, but remains attached to the latter, being 
apparently fixed within it, elongating and dividing as is indi- 
cated in the series of figures (c—g) which represent the succes- 
sive stages in the development of sucha rod. In very many 
cases the emerging rod may be seen, as in 7 and 4, to have 
penetrated the spore wall on both sides, so that two free ends 
project and continue to grow and divide as usual till the old 
spore wall disappears through absorption. That such appear- 
ances do not represent accidental superpositions, I have been 
able to determine to my own satisfaction. 
The addition of the following species, the number of which 
might be augmented by others that from lack of proper material 
I have been unwilling to publish, more than doubles the num- 
ber of representatives of the group formerly enumerated and 
serves to enforce with even greater emphasis than was before 
possible the fact that the course of development of these organ 
isms forms a distinct departure from that of other Schizomy- 
cetes, in that their life cycle, as has been pointed out, is divided 
into two distinct periods; the one of vegetation, the other of 
fructification or pseudo-fructification resulting from the con- 
certed action of many independent individuals toward this very 
definite end. This view is here reiterated for the reason that in 
one of the few references to the group that have come to my 
notice since the publication of my first paper, it is held that the © 
aerial character of the cysts, and not the circumstance just Men~— 
_ tioned, should be regarded as the crucial point of difference 
between the Myxobacteriacee and other Schizomycetes. AS 4 
