386 SECTIONAL TRANSACTIONS.—K. 
Dr. G. Bonp.—The influence of illumination on the development of the 
Casparian strip (3.0). 
Observations made by Priestley and his collaborators on a small number 
of plants suggest that the deposition of Casparian strips in the shoot of these 
plants is influenced by illumination. This matter has been further investi- 
gated in members of the Leguminosz. The above authors’ statements 
have been confirmed and extended to a number of related types, all of the 
sub-division Viciee. In the normal shoot of these plants a primary 
endodermis is present in the basal internodes only, while in the etiolated 
shoot the endodermal cylinder extends up to shortly behind the apex, and 
probably develops continually behind the latter. It is suggested that in 
these plants, although the shoot is potentially endodermis-forming, the 
secretion of the Casparian strip by the endodermal protoplast is suppressed 
by illumination. The reason for the development of the basal endodermis 
under normal conditions is as yet uncertain. 
A less marked response to etiolation was obtained with the other types 
investigated, although certain species displayed a definite approach to the 
Viciee group. 
Dr. S. WitL1aMs.—Regeneration in the Lycopodiales (3.30). 
Regeneration of various organs has been observed in all the genera of the 
Lycopodiales. ‘The author has experimentally induced regeneration in 
Selaginella grandis, Lycopodium Selago and Isoetes lacustris. Such pheno- 
mena will be described from the point of view of their bearing on various 
morphological problems and their relation to the intrinsic problems of 
regeneration only briefly mentioned. In Selaginella grandis regeneration 
of the shoot can be induced by removing the stem apices ; in these circum- 
stances rhizophore rudiments become transformed into leafy shoots. In 
other species regeneration of roots from decapitated rhizophores has been 
recorded. Such results have a bearing on the interpretation of the rhizo- 
phore. In Lycopodium Selago various types of regenerative growths have 
been induced on the stems and leaves of young plants grown from bulbils. 
The facts relating to these have a bearing on various problems such as 
the nature of the normal bulbils, the significance of the protocorm and the 
factors underlying vascular tissue formation. Similar adventitious growths 
have been recorded by Holloway and Goebel for other species of Lyco- 
podium. Osborn has described regenerative growths from isolated leaves 
of Phylloglossum which show features of interest for comparison with 
those described for Lycopodium spp. 
Prof. R. J. D. Granam.—The work of L. B. Stewart (4.0). 
It was Laurence Baxter Stewart’s brilliant work on vegetative propaga- 
tion by means of cuttings which attracted most attention. His success was 
achieved through careful observation and ingenious experiment. 
Results attained may be summarised as relating to: 
(1) Selection of Cutting—Determined by character of plant (1912), 
position of severing cut (1912) and season (1927). 
(2) Preparation and Insertion of Cutting —Blanching (1923), treatment 
for resin and latex (1912), retention of leaves (1912). 
(3) Creation of Environment.—Control of rooting medium (1912), aeration 
(1912), acidity (1922), water supply (1912), temperature (1912), disease. 
(4) Special Features—Response of cutting (1912), paring of callus (1912), 
cuttings without buds (stem internode, leaf, root), plants with horizontal 
branching (1927), inverted stem cutting (1927). 
