132 Canadian Record of Science. 



At the February meeting, a paper on the " Occurrence of 

 Arctic Plants " in New Brunswick from the pen of Eev. Prof. 

 Fowler, of Queen's University, Kingston, was read. Quite a 

 large proportion of the Arctic plants are found in New Bruns- 

 wick and the paper from Prof. Fowler was accompanied by a 

 list showing their distribution and occurrence. 



Movement of Tendrils. — D. P. Penhallow contributes an import- 

 ant paper to the American Journal of Science (xxxi. 46, 100 and 178,) on 

 the movement of tendrils in Cucurbita maxima and pepo, incidentally 

 dealing with other phenomena of growth in these plants. The results 

 obtained are based upon observations covering a period often years, 

 the original and principal facts having been obtained in 1875 by a 

 series of experiments which involved almost continuous observa- 

 tion through night and day, for a period of one week. He fully 

 discusses the relation which meteorological conditions bear to 

 growth, and confirms previous observations concerning the stimu- 

 lating influence of combined heat and moisture, but the retarding 

 effect of the former, when acting alone. The daily periodicity in 

 growth, dependent upon alternation of day and night, is shown to 

 be quite marked, the influence of conditions during the day being 

 found to be greater in promoting the general growth than the 

 retarding influence of sunlight, so that the general extension of 

 parts during the day exceeds that for the same number of hours of 

 night as 44.4 to 34.3, a result whi^h confirms that previously 

 obtained by Rauwenhoff. The most important facts, however, are 

 those relating to the mechanism of movement. This is found to 

 depend primarily upon the presence of three active bands of paren- 

 chyma tissue, which traverse the tendril throughout its entire 

 length, and by their more rapid rate of growth produce, through 

 unequal tension of the various tissues, all the phenomena of torsion 

 and circumnutation usually noticed. These bands, which the 

 author calls Vibrogen, in allusion to their peculiar relation to move- 

 ment, are found, one on the upper side of the tendril arm, and one 

 on each side, somewhat above the horizon of the major and trans- 

 verse axis of the section. Their direct connection with the circum- 

 nutation is most ingeniously obtained from the figures described 

 by the circumnutating tip of the tendril. Each figure is shown to 

 exhibit changes of direction in movement, which are exactly 

 reversed or follow an intermediate course, accordingly as any one 

 band is directly succeeded by greater activity of its opposite or the 

 remaining two bands ; the direction thus taken being the direct 

 expression of more vigorous growth in one band, or representing 

 the resultant of activity in two bands at the same time. He next 

 shows that the total latitudes of movement are one-half the total 

 departures, thus bringing out in a more conclusive manner the pre- 

 cise relation of vibrogen to motion. 



