Osborn.— Some Observations on the Tuber of Phylloglossum. 495 
almost reached maturity, while in Text-fig.’ 14 the cell- mass stage only had 
been attained by the injured leaf. 
An attempt to effect regeneration from portions of cone peduncles 
gave a negative result. The fragments, about 1 cm. long, were laid (July 
21) on the same sod of soil as the leaves of Series C. They remained 
green and turgid for over two months, but early in October began to look 
unhealthy. On October 21 one only was noticed to have formed a minute 
swelling near the middle on the upper side, but this peduncle fragment, 
like the others, had completely collapsed by the end of the month. It is 
remarkable, as will be seen below, for what length of time a broken frag- 
ment of Phylloglossum will remain green and apparently healthy on damp 
soil. On the other hand, once decay sets in it is very rapid, and in a day 
or two, since there is no hard tissue in the plant, little but the cuticle 
is left. 
(i) Series B. 
It will be convenient to consider this series first in some degree of 
detail, since it gave a high percentage of positive results. 
On July 11, 1918, a sod of soil containing many Phylloglossum plants 
was brought into the laboratory and placed in a glass dish. Eight leaves 
were broken off various well-developed plants growing in it and laid on the 
soil. The dish was covered and placed in the strong diffuse light of a south 
window. 
During the first month no growth was apparent ; the leaves remained 
turgid and green, the only visible change being a curving of some of the 
leaves in the vertical plane. This curving, however, was much less apparent 
than in some of the other series, especially A. 
I was unavoidably absent from the laboratory for the fortnight 
August 15 to 31. Before leaving, the leaves of this and the other series 
were examined under a hand-lens and the note made that none showed any 
growth. It was feared that all the experiments were failures (Series A 
had then been running for two months without apparent result). However, 
every leaf appeared healthy, turgid, and almost as bright green as when first 
laid upon the soil. 
Returning to Adelaide, it was surprising to find, on August 31, that 
every leaf of the series showed a distinct protuberance at or near the 
proximal end (Text-figs. 16-22). Three of the leaves were still lying hori- 
zontally ; two had the proximal end slightly elevated ; the three others were 
curved crescent-wise with both ends elevated. 
The development after this date was comparatively rapid. On 
September 16 four of the leaves were removed, sketched under the dissect- 
ing microscope, and carefully replaced in their original positions (Text-figs. 
16 A, 17 A, 18 a, and 19 a). They all showed irregular, greenish-yellow cell 
