188 BOTANICAL GAZETTE [ SEPTEMBER 
detailed account will not be necessary. The whole leaves pro- 
duced protonemata from the basal portion, and the cut leaves 
from all of the cut edges. The character of the growth from 
the leaf cells was practically the same. The formation of buds 
occurred in abundance in the light cultures, but none in the 
dark. The formation of protonemata was due to the separation 
of the leaf from the stem, and not to the mere cutting. 
An abundant protonema production occurred from the defol- 
iated stems, the growth taking place from the region of the leaf 
axil. The protonemal nature was generally suppressed in the 
dark cultures, only in a few cases long, unbranched, protonema- 
like growths being noted. The protonemata in the light pro- 
duced buds in great abundance, and often as lateral branches of 
the first cell of the protonemal filament. No buds whatever 
were formed in the dark. The protonema production was called . 
forth by defoliation, since whole plants only produced rhizoids, 
and not in the abundance which was noted in defoliated stems. 
As opposed to the other species studied, the defoliated stems 
did not produce new shoots as lateral branches, while whole 
plants under exactly the same conditions did. This is presum- 
ably explained by the small weak stem, which when robbed of 
its leaves is not able in itself to afford material for the growth 
of new shoots, in addition to what is used to produce the abun- 
dant growth of rhizoids and protonemata. 
5. BARBULA MURALIS, 
The leaves of Barbula produce protonemata with great readi- 
ness. Cultures of the detached leaves were made for both light 
and dark, and the best results were obtained from those upon 
pieces of flowerpot. After a lapse of about a week an abun- 
dant growth had appeared in the cultures in the dark as well as 
in the light. The first growth was colorless, with slightly 
oblique cross-walls, and no chlorophyll except what was derived 
from the leaf cell. Those which remained in the light for the 
entire period soon showed a very vigorous growth, with luxurl- 
ant branching and the absence of any bud formation. The walls 
