398 BOTANICAL GAZETTE [NOVEMBER 
come from the brown algae, and even the Characeae showing more resemblance 
to the brown algae than to other green algae. The origin of antheridia and 
archegonia from a plurilocular sporangium is developed along the lines already 
presented by Davis and Hotrerty. To some of us, it would seem better to 
derive antheridia and archegonia from plurilocular sporangia of some hypothetical 
green alga than to refer them directly to the plurilocular sporangia of brown 
algae. The spore mother cells of archegoniates are compared with the unilocu- 
lar sporangia of the brown algae, and the sporophyte of archegoniates with 
the thallus of brown algae. ScHENCK does not believe the sporophyte of pterido- 
phytes can be derived from that of bryophytes. Even the complicated antheridium 
of the Characeae is referred to the plurilocular sporangium of the brown algae— 
CHARLES J. CHAMBERLAIN. 
Translocation in green tissues.—RywoscH points out*? that translocation 
must depend upon the concentration gradient from the peripheral cells sg the 
vascular bundle. This gradient is due in part to the excess of food mace n the 
cells best illuminated, and also to the fact that transpiration cooperates doubly, 
by reducing the amount of water and by determining the movement of water. 
Thus those cells next the bundle are first to receive the water supply and those 
nearer the periphery are driest. He shows that the emptying of leaf tissues 15 
not simultaneous, peripheral ones being emptied first, and that the whole process 
is greatly retarded when transpiration is checked. [Yet it must not be forgotten 
that there are plants in which transpiration cannot be invoked as an aid to trans- 
location, since it is practically non-existent for weeks or months at a stretch] 
The concentration is also kept low in the inner cells by the making of starch ae 
em. Rywosc# also adds a note on the function of the starch sheath, holding 
that its character as a reserve is very doubtful.—C. R. B. 
Hygroscopic living leaves. —HANNIG?3 reports what he says is the first recorded 
instance of the movement of living leaves produced by variations in the water- 
content of the cell walls. The leaves of various hardy species of ododendron 
Tise and fall, roll and unroll, according as they are subject to freezing and ers 
ing weather respectively, though the same movements may be produced by 0 
conditions which reduce or increase the water-content of the cell walls. one 
'S not concerned, HANNIG says, because dead or live, narcotized or unnarco 
si is not 
leaves exhibit movements equal in extent and kind. HANNIG’s argument 18 ™ 
convincing, and it seems unlikely that this conclusion is sound. In wee ons 
little is known of the physics of water and cell contents under the ieee 
. Loe : 
CRB to make it possible to state accurately the precise relations in 
eerie | 4 
22 Rywoscu, S., Sur Stoffwanderung im Chlorophyligewebe. Bot. Zeit. O° 
121-130. figs. 2. 1908. a 
ANNI rs ; Ein 
*3 Hanwic, E., Ueber hygroskopische Bewegungen lebender Blatter bet Ei 
von Frost und Tauwetter. Ber. Deutsch, Bot. Gessells. 26a: 151-106. © 
