1906] CURRENT LITERATURE 157 
Aponogetonaceae, Juncaginaceae, Alismaceae, Butomaceae, and Hydrochari- 
daceae. From an investigation of, adult structure and manner of development, 
he has concluded that the axillary scales found at the bases of the leaves in the 
plants of these genera are homologous with the more specialized and solitary 
stipules of Selaginella and Isoetes. It will be recalled that Grsson regards the 
ligule as a sort of specialized ramentum, protecting and keeping moist the young 
leaves and growing apex of Selaginella and Isoetes.—FLORENCE Lyon. 
Reserve food of trees.— NiKLEWSKI?4 confirms by macrochemical methods 
the observation of Russow and of FiscHeER, that in winter the fat-content of 
trees first increases and. then dimirishes. The process cannot be reversed by 
temperature changes. While a rise of temperature accelerates the formation of 
fat, no change affects its solution. The transformation of fat and of starch are 
not related. Low temperatures promote the enim: of sugar from starch. 
Complex phenomena result from a rise of temperature. So great is the loss of 
reserves by the sedis a that ee seems = ba sone a other 
than starch or fat share it Ca 
‘ Conjugation of yeasts.—GuILLIERMOND’S has extended his studies on the 
conjugation of yeasts to several additional forms of the Schizosaccharomyces 
and Zygosaccharomyces. The union of the cells is followed by the fusion of the 
two nuclei, after which the fusion nucleus divides and the two cells separate or 
spores are formed in the fusion cell. In some forms conjugation takes place with 
the germination of the spores. GUILLITERMOND regards this cell and nuclear 
fusion as a sexual act, but of course chiefly on physiological grounds. Since we 
do not know the history of the yeasts, it is a matter of speculation whether or 
not these conjugating cells are phylogenetically gametes.—B. M. Davis. 
Amphispores in Uredineae.—ArTHuR has given an account of all species of 
rusts which have amphispores,”° 7. e., as defined by CARLETON, one-celled spores 
which resemble the teleutospores of Uromyces in appearance, but have two or 
more germ-pores, and in germination behave like uredospores, their function 
seeming to be to tide the fungus over unfavorable conditions. This account 
includes one species of Uromyces and eight of Puccinia, one of which, P. Garrettit, 
is new. All the forms are American, for thus far no cases of the occurrence of 
-amphispores have been reported from other parts of the world_—H. HassELBRING. 
Photosynthesis | extra vitam.—BERNarD has again examined carefully the 
24 NIKLEWSKI, B., Untersuchungen iiber die Umwandlung einiger stickstoffreier 
Reservestoffe wahrend der Winterperiode der Baume. Beihefte Bot. Centralbl. 
gt: 68— 
UILLIERMOND, M. A., Recherches sur la germination des . et la con- 
siti chez les lévures. Rev. Gén. Bot. 1'7:337-376. pls. 6-9. figs. IT. 10905. 
26 ArtHuR, J. C., Amphispores of the grass and sedge rusts. Bull. Torr. Bot. 
Club 32°35-42. figs. g. 1905. 
