3 eee 
1900] CURRENT LITERATURE 287 
2, In monocotyledons, conifers, and 68 per cent. of the observed dicotyle- 
dons no characteristic limit of the cortex is recognizable. The ring of 
mechanical tissue in the monocotyledons is from no point of view allied to 
the pericambium.— C. R. B 
Dr. F, Czapex describes™ a thermostat for use in experiments involving 
the use of a clinostat. The apparatus consists of a rectangular iron sand 
bath on four legs with leveling screws. This is heated by a microburnerand 
over it is seta copper box sheathed with asbestos and equipped with the usual 
thermoregulator and thermometer. The ends of the box are slit to pass over 
the axis of the clinostat which carries the experimental plants. These slits 
tan be closed by slides, except a circular aperture, which can be centered 
about the axis of the clinostat by means of the leveling screws of the base. 
Temperatures may be maintained constant within a degree for several days. 
The apparatus may easily be modified to furnish one-sided or uniform illu- 
mination by making part or all of the box of glass. A saturated atmosphere 
can be obtained by using water instead of sand in the pan.—C. R. B. 
CHARLES PALMER Nott has published an account* of the species of 
ee “lum of California, The paper is more than a description of the 
c for it contains a general discussion of the generic characters and of 
: seographical distribution. It seems that this genus of the red alge has 
ag distribution throughout the oceans of the globe. About seventy 
aes are known, ten of which occur on the west coast of North America, 
; eight of these are limited to California or neighboring shores. 4. corad- 
how th is described as a new species. The plates are photolithographs, and 
* plant forms and even the texture excellently.—J. M. C. 
* Ber, d, deutsch. bot. Gesells, 18: 131. 1900, 
ap : 
106. Calif. Acad. Sci. III. 2:1-46. is. 1-9. 1900. 
