1912] CURRENT LITERATURE 273 
in the spring. The maximum for carbohydrate reserves for deciduous trees 
appears to be at the period of leaf-fall, while that for evergreens is at the open- 
ing of buds in the spring. There seems to be insufficient evidence that cellulose 
acts as a winter reserve.—GEo. D. FULLER. 
Lens cells in plants.—The position of the investigators who contend 
that the lens cells occurring in the epidermis of various plants are not essentially 
organs of light perception will be strengthened by the results of SuMMERs,‘S 
for in the plants studied phototropic movement occurred only before the 
development of the lenslike cells. The plant studied is a native of Cape Colony, 
Africa, where it grows under conditions of intense insolation. The character 
of the epidermis changes with the age of the-leaves, which, at the time the lens 
cells differentiate, are quite rigid. An incrustation of calcium oxalate is 
found upon the epidermis, and this, we are assured, functions as a protection 
when solar illumination becomes too strong for the plant—Gro. D. FULLER. 
Embryo sac and embryo of Garcinia.—A series of investigations on 
the embryo sac and embryo of angiosperms, by the late Dr. TREuB, has begun 
to appear, the first paper dealing with two species of Garcinia (Guttiferae), 
G. Kydia, and G. Treubii. The details of embryo sac formation are described 
and illustrated, the variations being “st minor importance and all referable to 
categories recorded among angiosperms. The most noteworthy statement is 
that in reference to the evidence for prthenogensis which may be said to be 
suspected rather than proved. The paper. adds another angiospermous genus 
to those that have been aaa am still further emphasizes the remark- 
able uniformity of this great group in its essential morphology.—J. M. C. 
Nuclear extrusion among Fucaceae.—GARDNER" has ouicseiatn on 
the nuclear extrusion of six different forms of Fucaceae: Fuc 
typicus Kjellm., Hesperophycus Harveyanus Setchell and bude Pia: 
limita Gardner f. typica and f. lata, Pelvetia fastigiata Décne, and Cystosira 
Osmundacea Ag. Many irregularities were noted; for example, in the case of 
Hesperophycus the contents of the oogonium finally divided into two eggs, one 
of which included a single nucleus and the other seven nuclei; the fate of the 
eggs after escape from the oogonium was not followed. In the case of Pelvetia, 
the six es nuclei are cast out between the eggs instead of on the surface.— 
S. YAMANOUCHI. 
sdermic of A, h i] 
48 SUMMERS, F., On the occurrence of lens cells in th 
mum pseudoiruncatellum. Ann. Botany 25:1137-1145- 1911. 
4 Trevus, M., Le sac embryonnaire et l’embryon dans les angiospermes. I. Gar- 
cinia Kydia Roxb., Garcinia Treubii Pierre. Ann. Jard. Bot. Buitenzorg 2421-17. 
pls. 1-5. IQII. : 
47 GARDNER, NATHANIEL Lyon, ergo in gees extrusion among Fucaceae. 
Univ. Calif. Publ. Bot. 4:121-136. ple. 16, 17. 
