330 JOSEPH HALL BODINE 



extends over a much shorter time. Recovery from acetone is 

 never complete; the respiratory movements in some cases begin, 

 but the animal is never able to use its limbs and eventually dies. 



Xylol. The effects of xylol are marked and take place in a 

 relatively short time. Respiratory movements are slowed and 

 cease in from three to five minutes. 



Figure 4 shows the effect of a small dose on the CO2 output. 

 An increase followed by a decrease takes place. The effect is 

 irreversible. 



Fig. 5 Curves showing the effect of 2 drops — 0.08 cc. — formaldehyde (curves 

 A and B) on the CO2 production of grasshoppers. The point marked on the 

 abscissa indicates the beginning of exposure to formaldehyde for curves A and B; 

 previous to this the normal production of COo was determined. The normal rate 

 (which is taken as 100 per cent) corresponds to the production of a definite amount 

 of CO2 in 10.5 minutes for curve A and in 5 minutes for curve B. Curves A and 

 B irreversible. For further explanation see text. 



Formaldehyde. It is well known that insects are able to with- 

 stand large doses of formaldehyde. The following results seem 

 to substantiate this fact. With a dose of formaldehj^de strong 

 enough to cause an unpleasant reaction when applied to the 

 nose, the respiratory movements of grasshoppers continue quite 

 normally for a period of two hours and over. 



Figure 5 shows the effect of such a dose of formaldehyde on 

 the COo output. An initial increase takes place, followed by a 

 decrease, which in magnitude is similar to the normal rate. 

 Larger doses produce the same effect, but the decrease following 



