332 JOSEPH HALL BODINE 



followed by a marked decrease with irreversible doses was noted. 

 No explanation of these differences is given other than that they 

 are probably due to the differences in the material used ; in the 

 one case all animals were aquatic, while in these experiments 

 they were not aquatic. Results obtained by Tashiro (11) have 

 not been compared with the present results because of the dif- 

 ferences in methods and materials used in the experiments. 

 The results obtained for different plant material by Haas (2), 

 Gustafson (3), Brooks (4), Thomas (5), and others on the effect 

 of ether on respiration are quite similar to those found for grass- 

 hoppers, since an increase followed by a decrease was almost 

 always obtained. The effects of chloroform on the CO2 output 

 of grasshoppers resemble those found by Miss Irwin (6) for 

 irreversible doses of ether— a decrease followed by an increase 

 which in turn is followed by a decrease. The results for acetone 

 are similar to those reported bj^ Haas (2) for Laminaria, in which 

 the initial increase in CO2 output remained approximately con- 

 stant over a large number of periods and then gradually de- 

 chned, and eventually, with high concentrations, fell very rapidly 

 below the normal. Gustafson (3) with Aspergillus niger also 

 found strikingly similar results. Formaldehyde in large doses 

 acts similarly'- for grasshoppers as for plants as reported by Haas 

 (2) and Gustafson (3). With a dose in which the respiratory 

 movements of the grasshopper are not affected, however, we 

 get an initial rise, followed by an almost normal rate. 



The bearing of the above results on the various theories of 

 narcosis, and especially that of Verworn in which anesthesia 

 is described as a kind of asphyxia, is of some interest. They 

 seem to show that the action of anesthetics is due to some other 

 cause than the effect on respiration. 



The interpretation of the action of various anesthetics on the 

 different tissues of the grasshopper is of importance, but will be 

 left for future consideration. It is of interest, however, to point 

 out here that different effects of anesthetics and other substances 

 upon the germ cells of grasshoppers have been noted by McClung 

 (9). This author has shown that killing animals with cyanide 

 and by decapitation produces results different from those by 



