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SUMMARY OF CURRENT RESEARCHES RELATING TO 
greater solubility and of its more rapid osmosis to and from the cysts ; 
or it may be due to such unknown factors as the partial pressure of the 
gases in the mixture, or the varying pressures to which the plants 
are subjected with the periodic rise and fall of the tides. The source of 
variation in quantity of both gases is to be traced to the processes of 
metabolism in the plants. The pneumatocyst not only raises the plant 
to the light, but serves also as a reservoir in the gas exchange of the 
metabolic processes, and this ready supply of essential gases may have a 
bearing on the enormous annual growth of these plants. E. S. G. 
Gas Pressure in Nereocystis. — T. C. Frye {Puget Sound Marine 
Station Publications , 1916, I., 85-8). Among the results obtained by 
investigation are the following : The gases within the air cavity of the 
cyst average about 77 mm. of mercury below air pressure. The loss of 
fronds causes a rise of pressure within the air cavity until it approaches 
or even exceeds that of the atmosphere. There is also a fall of pressure 
at night, and a lower pressure in submerged plants. These reductions 
are probably due to changes in temperature. A. G. 
Seasonal Development of Bladder Kelp. — George B. Rigg ( Puget 
Sound Marine Station Publications , 1917, I., 309-18). A record of 
observations made during a number of years. Nereocystis is an annual 
plant. Young plants are found in the spring, fruiting plants in the 
summer, and drifting old plants in the winter. Some survive till the j 
following year. Mortality is great among the sporelings, through j 
desiccation, excessive, light, wave violence. These and other factors are 
discussed. A. G. 
North Pacific Coast Species of Besmarestia. — Yinnie A. Pease 
{Puget Sound Marine Station Publications , 1917, 1., 383-94, 2 pis.). A 
preliminary study of the subject, with a history of the genus. Of the 
species recorded for the region, Besmarestia aculeata is fairly common, 
D. media is considered to deserve specific rank, D. viridis probably does \ 
not occur there, D. ligulata is rare, D. herbacea is abundant and deserves i 
specific rank, D. tabacoides is a curious undivided species described from 
Japan by K. Okamura in 1908, and now discovered in Puget Sound by L 
the author. A key and some photographic figures add to the value of 
the paper. A. G. 
The Germination and Development of some Marine Algae. 
II. Phyllitis. — K. Yendo {Bot. Mag. Tokyo , 1919, 33, 171-84, 1 pi.). 
The alga under consideration in this report is Phyllitis Fascia , the 
young shoots of which begin to appear late in October in the vicinity of ! 
Otaru Bay. Spores are discharged from late December to the following 
April. At the end of June the plants are mostly broken away from | 
their attachment, and in July they are no more to be found. Early in 
April fronds with mature sori were placed under observation in Sapporo 
Laboratory, and within twenty -four hours the spores were massed on 
the side of the glass towards the light, being strongly heliotaxic. Two 
cultures were made, but one only, the more successful, is here described. 
After losing the flagella, the spores become spherical and sink to the ; 
bottom of the glass vessel, to which and to each other they adhere by a 
