[Vor. 5 
228 ANNALS OF THE MISSOURI BOTANICAL GARDEN 
yeast in presence of chloroform. Siragusa (’79) reported the 
failure of long ether exposure on subsequent activities of bac- 
teria, yeasts, and molds, but this early work may be ques- 
tioned. Elfving (’86), studying yeasts among other objects, 
noted increased carbon dioxide production by such organisms 
from dextrose and asparagin in presence of narcotics. Swarm 
spores of Chlamydomonas pulvisculus showed a reversal of 
phototactic response from negative to positive in the presence 
of ether. Chloroform, on the other hand, proved toxic. 
Rothert (’03) essayed to determine tactic effects of anaes- 
theties on mieroórganisms as distinct from effect on motility, 
and reported varying chemotaetie inhibition effects of ether. 
Bacillus Solmsii had its chemotactic response inhibited by this 
substance, but not by chloroform. Gonium pectorale, on the 
other hand, was partially affected as to phototaxy by chloro- 
form. Rothert also reeorded a noteworthy reversal of photo- 
taetie response (negative to positive) and a shifting of the 
light intensity optimum. An osmotactie susceptibility was 
completely inhibited by a nareosis which only inhibited chemo- 
taxy and ‘‘aérotaxy’’ to varying degrees. While motility 
was found to depend on length of exposure, anaesthetic ef- 
fects were held to bear a relation solely to the concentration 
used. А distinction is thus made between a narcotic and a 
progressive toxie action. 
The results of the studies of Herzog and Hórth ('07) on the 
effects of vapors on yeast autolysis will be considered under 
another heading. The fermentation experiments of Koch 
(71) indicated a definite stimulus to activity of yeasts by 
small ether dosages. Fred ('11) also noted a stimulus to 
baeterial growth effected by ether in small concentrations, 
and even reported an increased nitrogen-fixing capacity of 
Azotobacter in pure culture as a result of etherization. 
Harvey (715) has found that when ether or chloroform, among 
a series of compounds tested, was added to tubes containing 
a sea-water emulsion of luminous bacteria, the light emitted 
by the organisms disappeared almost immediately. He does 
not state, however, whether the action is reversible, as was the 
ease with various alcohols used. 
