XXX Trans. Acad. Sci. of St. Louis. 



also, if a tropic response be obtained, in how far this might be 

 altered by change in environmental conditions. 



Results of extended work on B. termo and B. suhtilis demon- 

 strated without any question that pure cultures of these bacteria 

 gather under the influence of very weak currents at the cathode 

 and follow the reversal of poles. 



Pure cultures grown in acid-modified and alkah-modified pep- 

 tone gelatin appeared to respond in most cases, though not in 

 all, in opposite manner, alkali cultures gathering at the cathode 

 and acid cultures at the anode. 



These results seem to be in harmony with those of Greeley on 

 Paramecium, and give color to the conception that the galvano- 

 tropic response is due to, or directed by, the physico-chemical 

 constitution of protoplasm. 



May 6, 1907. 



Mr. J. H. Kinealy in the chair; attendance, twenty. 



The Corresponding Secretary presented an invitation from the 

 New York Academy of Sciences to be represented by a delegate 

 and by a written memoir on the work of Linnaeus at their meet- 

 ing commemorating the two hundredth anniversary of the birth 

 of Linnaeus. Upon motion of Professor Trelease the Corre- 

 sponding Secretary, in consultation with the President, was in- 

 structed to send appropriate communications to the New York 

 Academy on this occasion. 



Dr. Perley Spaulding presented an illustrated paper on ''The 

 Botanists of St. Louis. '^ He spoke of the life and work of the 

 following botanists : — 



1803-1804— Lewis and Clark Expedition. 

 1810-1811— John Bradbury and Nuttall. 

 1819 — William Baldwin with Long Expedition. 

 1820 ' — Edwin James with Long Expedition. 

 1820-1822— Dr. Lewis C. Beck. 



1831 — Thomas Drummond. 



1832 — Prince Maximihan. 

 1834 —Thomas Nuttall. 

 1835-1884— Dr. George Engelmann. 

 1838 —Nicholas Riehl. 

 1839-1855— Dr. Theodore Hilgard. 

 1845-1864— August Fendler. 



