62 



SCIENCE 



[N. S. Vol. XXXI. No. 785 



of non-electrolytes which are necessary to 

 produce a reaction on the plant organism. 



There seems to be a much greater uni- 

 versality in the manner of the response to 

 stimulation by poisons than in their actual 

 toxic effect, a fact that has already been 

 noticed, and for that reason I am strongly 

 inclined to the opinion that the former does 

 not depend upon the particular form which 

 the latter may take, and so the increased 

 enzymatic action may be considered to be a 

 general phenomenon connected with this 

 class of response. 



There at once suggest themselves many 

 veiy interesting problems in regard to the 

 relation of chemical stimulation to morbid 

 hypertrophies— using the word in its broad- 

 est sense— in higher plants, and also to 

 what might be called the normal hyper- 

 trophies which ensue in the tissues of the 

 ovary wall and surrounding parts after 

 fertilization, without touching on the great 

 question of the development of the fertil- 

 ized egg itself. 



In a previous address before this section, 

 attention was called to the possible en- 

 zymatic changes induced by untoward 

 chemical stimulation of the germ cells of 

 certain plants and the results of this stim- 

 ulation on the offspring. In the light of 

 my own acquaintance with the question of 

 chemical stimulation I see nothing improb- 

 able in such a point of view, even though 

 we can not prove it at present. 



There are many other considerations in 

 connection with the question which might 

 be profitably discussed and I am aware 

 that I have really touched upon one side 

 of the problem only, practically neglecting 

 the morphogenic influence of chemical 

 stimulants, but sufficient time has already 

 been consumed and to open up new topics 

 would be but to strain your patience fur- 

 ther. The point which I have endeavored 

 to develop and which I here repeat is that 



the chemical stimulants which have been 

 discussed produce their effect indirectly 

 and the nature of the response appears to 

 be one of the increase of constructive en- 

 zymatic action over that which would take 

 place under normal conditions from an 

 equal and similar food supply. 



H. M. ElCHARDS 

 Baenaed College, 

 Columbia Univeesitt 



PUBLIC LECTURES AT THE HARVARD 

 MEDICAL SCHOOL 



The faculty of medicine of Harvard Uni- 

 versity offers a course of free public lectures, 

 to be given at the Medical School, Longwood 

 Avenue, Boston, Saturday evenings at 8, and 

 Sunday afternoons at 4, beginning January 2, 

 and ending April 30, 1910. Doors will be 

 closed at five minutes past the hour. No tick- 

 ets are required. Following is a list of the 

 lectures and their subjects, with dates: 



January 2 — " The Influence of Mental and Mus- 

 cular Work on Nutritive Processes" (illustrated), 

 by Dr. F. P. Benedict. 



January 8 — " The Story of "Vaccination," by 

 Dr. M. J. Kosenau. 



January 9 — " What the Public should know 

 about Patent Medicines," by Dr. M. V. Tyrode. 



January 15 — "Clean Milk" (illustrated), by 

 Dr. Calvin G. Page. 



January 16 — "The Growth of School Children 

 and its Relation to Disease," by Dr. W. T. Porter. 



January 22 — " Sprains, Strains and Fractures : 

 Simple Facts of Diagnosis and Treatment " ( illus- 

 trated), by Dr. J. B. Blake. 



January 23 — " The Glands of Internal Secretion 

 and their Relations to Health and Disease " (illus- 

 trated), by Dr. W. B. Cannon. 



January 29 — "Small-pox" (illustrated), by 

 Dr. J. H. McCollom. 



January 30 — " Hearing and Speech," by Dr. C. 

 J. Blake. 



February 5 — " Posture and Carriage as affected 

 by School and Clothing," by Dr. R. W. Lovett. 



February 6 — " The Care of Infants with Special 

 Reference to the Prevention of Disease," by Dr. 

 Maynard Ladd. 



February 12 — " Voice Production," by Dr. J. 

 Payson Clark. 



