1896 | CURRENT LITERATURE 183 
trib. of 1888); Callicarpa Pringle? is a new species from San Luis Potosi 
(Pringle 3094); Vitex Hemsley? is a new species from near Oaxaca (/urgen- 
sen 68), referred to by Hemsley in Biol. Centr.-Am. Bot. 2 1540; Citharexylum 
Jurgenseni is a new species from near Oaxaca (Jurgensen 259); and the 
remaining nine species are mostly from northwestern South America.— J. M. C. 
ABOUT A YEAR and a half ago Askenasy suggested that the vexed question 
of the ascent of water in plants was explicable by the force of imbibition of 
the cell-walls of the leaves and the cohesion of the water columns in the 
ducts.° He has devised an ingenious apparatus to illustrate the physical 
principles involved, which imitates fairly well the conditions in the plant. 
The fault common to the apparatus used by Jamin, Naegeli, and Strasburger 
is that the conducting portion consisted of porous material and was not 
essentially different from the evaporating and lifting portion, Askenasy’s 
@pparatus consists of a glass tube 90™ long and 2.2—3.5°" in diameter, 
ending in a small funnel which is plugged with gypsum or even has the 
Sypsum spread over its whole inner surface. The ypsum corresponds to the 
membranes ‘of the leaf, the tube to the wood vessels in which the water 
ascends, With certain precautions the tube is filled with water, its open end 
'mmersed in mercury, and fastened upright. In one experiment in 33 hours 
the mercury rose to $2, and in another in 26 hours to 89%, z. é., into con- 
tact with the gypsum. In the first its complete ascent was hindered by the 
formation of an air bubble. (Cf Bot. Centralb. 66: 379. 1896)—C. R. B. 
Dr. MAXWELL T. MASTERS has published from time to time the results 
* his researches among the Coniferze. His most recent contribution deals 
with the genus Cupressus," which he has reexamined with fuller material and 
“sistance. The genus he regards as well-defined among its allies by the pel- 
tate expansion at the free end of the cone-scales, but the species are very dif- 
ficult of limitation on account of the great inconstancy of the characters used, 
= ope as the long cultivation of many of them. They are remarkably poly- 
re ai 4 certain well-known “stage of growth” in some species having 
dig ris to the old genus Retinospora. The author regards Chamacyparts 
Nea “as generic rank, and is inclined to believe that the closely allied 
tion of ay oo “us might well be merged under Cupressus. His presenta- 
to pas alliances represents two divergent lines from Cupressus ; one leading 
. vus; the other, through the Chamecyparis forms, leading to Thuya, 
iol “ala and /itzroya. The varieties of foliage are discussed, but no phys- 
Bis ad Phylogenetic significance suggested as explanatory of their 
PNR. Hat Rist ic: F ‘ Cent. 
Giiay. ie ist.-med. Ver. zu Heidelberg N. S. 5 : (1-23). 1895. ( Bot. Cen 
tM ie A 
ASTERS, MAXWELL T.— A general view of the genus Cupressus. Jour. Linn. 
Pee Bot. 31 * 312-363. 1895. 
