36 Mississippi Valley Horticultural Society. 



These illustrations show conclusively, we think, that the doctrine oi the 

 "descent of the sap" is a fallacy. To cause an upward jl()U',\\%\\i,m.o\ii\.\\ve 

 and heat are necessary, for if these be excluded, exhalation is entirely pre- 

 vented. And we conclude that in the case of those portions of the grape- 

 vine, cherry, tig and flowering shrubs growing inside of a hot-house and bay 

 window, exposed to these three influences, these caused their buds to swell, 

 unfold leaves and bear flowers and fruit, whilst the trees and shrubs outside, 

 of which they were a part, were in a dormant state. These illustrations also 

 prove that the " flowing sap" begins to move in the upper branches long be- 

 fore the ascending sap commences its upward flow from the roots. 



Of all the many divisions of natural science, vegetable physiology is of in- 

 calculable value to the practical horticulturist. The principle upon which it 

 rests point to every operation within his province, and show him, unerringly, 

 as no other system can, the errors and mistakes of his daily practice; and as 

 the finger-board by the roadside assists the benighted traveler, so does the 

 study of plant life open up new ideas and suggest new modes of culture, 

 based upon truths that can not be combatted. 



The number of horticulturists are too few who to-day can explain the va- 

 rious functions which roots, stems, leaves and flowers have to perform, or 

 what action or changes t^ike place during the growth of these organs of vege- 

 tation; and yet, a i)erfect knowledge of these principles will render more 

 valuable assistance to the diligent inquirer after truth than all else besides. 



Botanical science, unai)plied, is of no value whatever to the horticulturists 

 of the Mississippi valley. But this science, applied for practical purposes, is 

 the best science, the only science, that will aflford us help in carrying forward 

 the great work in which we are all engaged. 



In pursuit of truth, the student must accept of Dame Nature as his teacher. 

 Let him take her by the liand and enter her temple; there he will make the 

 best of her and she of him. They will get on together rarely, she as his ever 

 beneficent mother, he as her mouthpiece, her conscious self, her minister 

 and interpreter. 



DISCUSSION ON VEGETABLE PHYSIOLOGY.* 



President Earle, of Illinois — I am pleased that our meeting .should 

 open with .such an able and exceedinjj^iy interesting pai)er. A few 

 minutes will now be devoted to the discussion of Prof. Robson's 

 paper. 



3fr. il/mi.son, of Texas — It is a fatal mistake to trim oil' the young 

 linib.s, as they are a source of supply to the older portions of the 



*NoTi:. — The Secretary regrets that he can not give a better report of the able 

 discUKsionsof tliis and the sueceeding session. This is due to the al)scnce of liis as- 

 sistant who dill not arrive, owing to iniavoi(lal)ie detentions, until the following 

 (lav. Secretary. 



