244 Transactions of the Canadian Institute. [Vol. VII. 



(1880, p. 313) was exhaustive, and he thought he had settled the 

 question of water-absorption ; and, as he says, he thought he had settled 

 it in the affirmative. Lindley in his early work (1866, p. 193) referring 

 to stomata, says : — " It is by means of this apparatus that leaves absorb 

 water and gaseous matter from the atmosphere." In Lindley's "Theory 

 of Horticulture," (1859), the belief is expressed that leaves do absorb 

 fluid from the air ; and it is stated that the stomata are well adapted to 

 this purpose. Lindley refers at some length to the work of Knight 

 (1886), in which it is stated that leaves may absorb to the extent that a 

 descent of sap is produced in the alburnum, and also that one leaf may 

 be made to supply its neighbour below it with water. Gregory (1886) 

 proved that leaf hairs of many plants contributed actively to the supply 

 of water in the plant. 



Since this time but little work of importance has been done, though 

 the question seems farther from being settled now than it was a 

 hundred years ago. Of the later works on the subject, two of them are 

 deserving of mention, — Burt (1893), and Ganong (1894, p. 136). The 

 former concluded that leaves and cut shoots may absorb water, while 

 the latter concluded that leaves do not function as water absorbers to 

 an extent sufficiently great to be worthy of note. 



As to the text books on botany and on plant physiology, other than 

 those mentioned, commencing with Pfefifer, one finds that the positions 

 taken, though varied to some extent, are generally and rather uniformly 

 on the side of non-absorption ; at least one might say, judging from the 

 attention paid to the matter, it was considered of little or no physio- 

 logical importance. It is interesting to notice further that of those 

 works, such as Pfeffer (1881) and Detmer (1883), that have been 

 recently revised, there is little modification of the view rather cautiously 

 expressed in the early editions ; and, with a proviso or two, practically 

 the same stand is taken in the latest editions as in the first. This is as 

 might be expected, for no work of any importance had been done in 

 this line in the meantime. Sachs, in his "Plant Physiology" (1887) 

 takes the ground that the question has not been at all satisfactorily 

 settled. In Goodale's Physiology almost no attention is given to the 

 matter. Van Tieghem (1884) states that water vapour is readily 

 absorbed by the plant. Vines (1886) gives some attention to the 

 subject, but leaves one to infer rather than to read his conclusions. He 

 admits that under peculiar circumstances water and dilute solutions 

 may be absorbed, but holds generally to the idea that this, if it be a 

 function at all, is of but little consequence. In both works of Pfeffer 



