ma CURRENT LITERATURE 17 
sugar; coir, a commercial name for the fiber obtained from the husk of the 
coco-nut; copra, the desiccated kernel or oil-cake; and oil.—J. M. C. 
Cocoa.—The important cultural plants of the tropics are gradually becom- 
ing known from the modern standpoint, and the most recent contribution in 
this field is the large volume on cocoa by VAN HALL, director of the institute 
for plant diseases and cultures at Buitenzorg, Java. In the brief historical 
account it is stated that the first knowledge and use of the plant came to Europe 
graphical distribution and climatic conditions, Chemistry of cocoa and cocoa 
soils, Botanical characteristics of the cocoa plant, Varieties of cocoa, Cultiva- 
tion af cocoa, Fermentation, Diseases and enemies, Cocoa-growing countries.— 
J.M.C 
Flora of California.—Part 5 of A flora of California by JEPsoN® has just 
appeared. The first parts were noticed in this journal,’ attention being called 
to the general high character of the work. This part completes the Portula- 
caceae, includes the Caryophyllaceae, and begins the Ranunculaceae. A new 
genus of Caryo tine is since (Eremolithia), based upon Achyronychia 
Rixfordii Brandegee.—J. M. C. 
NOTES FOR STUDENTS 
The gases in the floats of marine algae.—This subject has attracted the 
attention of a number of investigators during recent years. The fact that it 
is being investigated from so many points of view gives hope that we may soon 
have fairly complete knowledge of the subject. Lucas* has investigated the 
subject from the point of view of the origin of the gas. The following Austral- 
ian marine algae have vesicles filled with gas: Sargassaceae (Sargassum, Car- 
pophyllum, Turbinaria, Cystophora, Cystosira, Scaberia, Phyllospora), Fucaceae 
(Hormosira), and Laminariaceae (Macrocystis and possibly Adenocystis). In 
young plants, and even in mature fruiting individuals in sheltered situations in 
shallow water, there are no vesicles. 
5 VAN ees Dr. C. J. J., Cocoa. 8vo. pp. xvit-515. figs. 140. London: Mac- 
millan. 1914. 
PSON, W. ae A flora of California. Royal 8vo. Part V, pp. 465-528. Jigs. 14. 
San Francisco: H. S. Crocker Co. IgI4. 
7 Bor. Gaz. 49:153. 1910. 
® Lucas, A. H. S., The gases present in the floats of certain marine algae. Proc. 
Linn. Soc. New South Wales 36:626-631. 1912. 
