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them in abundance earlier in the year. From an examination of 
the American species it would seem that the greater number 
possess two or more distinct or confluent glands situated where 
the blade and petiole join, and in these few species where none 
were discovered, it is quite possible that a closer examination 
in the spring time may show that they exist. Thus on P. tremula, 
the weeping variety, a careful examination in early May failed 
to show a single gland ; but a week or two later, after several 
days’ rain, the young branches grew very rapidly for a short 
time, unfolding many new leaves, and the first three or four of 
these on each branch bore large and active glands. The nectar 
_ is greedily gathered by insects, chiefly Hymenoptera and Diptera. 
The most numerous were the ants, who, as is usual in such cases, 
would fight rather than give up a good position near a nectar- 
secreting gland. The author regards these glands as protective. 
(The Botanical Gazette, Crawfordsville. November, 1881.) 
FAUNA AND FLORA OF THE WHITE SEA.—At a meeting 
of the Natural History Society of St. Petersburg (April 23, 
1881) Dr. Chr. Gobi gave a sketch of Prof. Cienkowski’s report 
on his expedition to the White Sea, which appears in the Pro- 
ceedings of the Society, in the Russian tongue, and is illustrated with 
three coloured plates. The bathymetrical distribution of the 
algze seems to show a connection between the marine flora of the 
Solowezk Islands and that of the Scandinavian and Arctic 
coasts. Inthe White Sea there is a distinct though fully deve- 
loped littoral zone, chiefly marked by the presence of Fucoids, 
with a few Chlorophycez and Floridez. As new to the White 
Sea flora may be mentioned Bu/bocaulon piliferum, Pringsh., 
and Glocothamnin palmelloides,Cnk. The sea was by no means 
Tich in microscopical organisms, but still a few new and inter- 
esting forms were found, and are described and figured, such as 
Wagneria mereschkowskit, a new genus and species of Protista, 
somewhat between Haeckeliana and Clathrulina ; several new 
Flagellata, Afulticilia marina, new genus and species having a 
protoplasmic body of protean form without nucleus or contractile 
vesicle, but having several cilia; Zauviaella marina also new, with 
an ovum-like body, flattened horizontally at the top, with two cilia 
and one ortwo round marks (Schildchen) ; Daphnidium boreale n.g. 
and sp., with a spherical body, prolonged into a curved beak, giving 
origin to one long cilium. In the dead cells of Pylaicella and 
other Phzospores there was found a colourless form of a Laby- 
rinthula which had previously been found thriving in the cells of 
a Lemna ; Finally, a new Moner, Godiella borealis, which shows 
a great resemblance to Vampyrella, but the green contents seem 
never to extend into the pseudopodia (Aotanische Zeitung, 
January 13, 1882.) 
THE GROWTH OF PaLMs.—In a paper (Russian) recently 
read before the Botanical Section of the St. Petersburg 
Natural History Society, Mr. K. Friderich describes in detail 
the anatomical structures to be met with in the zrial roots 
of Acanthorhiza aculeata, these roots presenting a remarkable 
example of roots being metamorphosed into spines. Supple- 
menting this, E. Regel made the following remarks :—Palm 
trees, grown from seed, thicken their stems for a succession 
of years, like bulbs, only at the base. Many palms continue this 
primary growth (7.e. the growth they first started with) for fifty 
to sixty years before they form their trunk. During this time 
new roots are always being developed at the base of the stem, in 
whorls, and these always above the old roots. This even takes 
place in old specimens, especially in those planted in the open 
ground which have already formed a trunk. In such cases the 
cortex layer, where the roots break through, is sprung off. In 
conservatories, under the influence of the damp air, this root- 
formation, on which indeed the further normal growth of the 
palm depends, takes place without any special assistance. When 
the palm is grown in a sitting-room, one must surround the base 
of the trunk with moss, which is to be kept damp, in order to 
favour the development of the roots. When the base of the 
palm-trunk has almost reached its normal thickness, then begins 
the upward development of the trunk which takes place more 
slowly in those species whose leaves grow close together than in 
those whose leaves are further apart. In specimens of many species 
of Cocus and Syagrus, whose leaves are particularly far apart, 
the stems grow so quickly when planted in the open ground that 
they increase by five to six feet in height per annum, The stem 
of those palms which develop a terminal inflorescence have ended 
their apical growth by doing so, and wither gradually. In addi- 
tion to this (withering) in the case e.g. of Arenga saccharifera, 
new inflorescences are developed from the original axils (Blattach- 
seln) from aboye downwards, so that one sees at last the already 
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leafless trunk still developing inflorescences in the direction 
towards the base of the trunk, Almost all palms with this latter 
kind of growth develop off-hoots in their youth at the base of 
their trunks which shoot up again into trunks after the death of 
the primary trunk, if they are not taken off before. As to 
the structure of the palm-trunks out of unconnected wood- 
bundles, the assertion has been made that the palm-stem does 
not grow thicker in the course of time, and that this is the 
explanation of the columnar almost evenly thick trunk. But 
careful measurements that were made for years have led Regel 
to the conclusion that a thickening of the trunk actually takes 
place, which probably amounts to an increase of about a third over 
the original circumference of the trunk. 
ACTION OF GASES AND LIQUIDS ON THE 
VITALITY OF SEEDS 
M Y experiments extend over a period of nearly three years. 
They were made principally with the seeds of Medicago 
sativa, these seeds resisting in a remarkable manner the action 
of chemical agents. The observations were very numerous and 
frequent ; but in the present abstract those results alone are given 
in which the action of the gases and liquids lasted longest. 
I. Action of Gases.—The chief difficulty in these experiments 
is an easy method of keeping many samples of seeds in the 
several gases the action of which is to be tested. I devised the 
following simple plan :—A thick glass tubing was heated in 
the middle and blown into a bulb of sufficient size to contain a 
certain quantity of seeds and a relatively large volume of gas ; 
after introducing the seeds into the bulb, the two extremities of 
the tube were heated, and drawn out, so as to form, on each side 
of the bulb, a nearly capillary neck; one end was left free, while 
the other was connected, by means of an india-rubber tube, with 
the generator of the gas that was to fill the bulb. The air was 
completely displaced in the latter by allowing the gas to pass for 
some time through the apparatus; after which, without pre- 
viously interrupting the passage of the gas, the bulb was sealed 
by fusing at the blowpipe the two capillary necks. 
I prepared a large number of bulbs with seeds and with dif- 
ferent gases; the greater number of bulbs contained air-dry 
seeds, while some contained seeds that had been moistened and 
swollen with water. On opening the bulbs the seeds were sown, 
and their vitality measured by the percentage of those that 
germinated on moist quartz sand. 
Experiments with air-dry seeds of Medicago sativa in dry 
gases :— 
Number of days in Percentage of seeds 
Gas. which the seeds re- that retained the 
orate in vase gas. germinating power. 
: 4 fore than 
Air (not in bulbs) ...4 42, years 83 
Air (not in bulbs—an- { More than = 
other sample)... | three years 5 
Nitrogen Aes nas 789 93 
Oxygen «e aes 758 59 
Hydrogen... Fa 1005 63 
Carbon monoxide ... 803 ¥- =) 93 
Carbon dioxide ame 1035 a mh 24 
” ” ane 408 73 
Marsh-gas_... en 550 58 
Nitrogen protoxide ... 214 jo 
s3 nodioxide= ess 776 48 
Ammonia... Fs 832 o's 
9 evs ae 398 ist Fe 1'2 
Sulphur dioxide ee 838 oe aed 4°5 
e $s ce 405 a oe 10°6 
Sulphuretted hydrogen. 976 5a = 58 
Arseniuretted _,, 02 5 87 
seeds, and destroy their vitality. 
seeds can resist for so long a time the action of nitric oxide, 
of sul; huretted hydrogen, and of sulphur dioxide, and how some 
can even survive the action of dry ammonia-gas. The percentages 
that represent the vitality of the seeds that have been under the 
action of the different gases cannot be compared, for the expe- 
riments were not all begun at the same time, nor extended over 
the same period, nor was the same sample of seeds used in all 
the experiments. 
Whenever seeds moistened with water are kept in the aboyve- 
named gases, their germinating power is very rapidly destroyed. 
