16 HENRY H. P. SEVERIN AND HARRY C. SEVERIN 



diately after the insect came out of each feint, it was stroked 

 with a camel's hair brush and put back into the immovable 

 position again. It was found that as the blotting paper lost a 

 considerable amount of moisture and the bugs became dry on 

 the ventral surface, it was not long before the hemiptera usually 

 came out of the death feint. The following figures indicate the 

 averages of the first three successive death feints in each speci- 

 men: lo, 12, 23, 25, 26, 30.5, 3i,_34.5. 42.5, 45. 46, 58, 59, 59.5, 

 65, 66.5, 68.5, 69.5, 71 and 104 minutes. The average of these 

 averages, or the total Average, is 47.3 minutes. One would not 

 hesitate to conclude from this experiment that the duration of 

 the death feint is increased under these conditions. 



From the experiments upon the effect of dryness and moisture 

 on the duration of the death feint, one is strongly inclined to be- 

 lieve that the death feint is increased by a large amount of watery 

 vapor in the atmosphere and decreased in a dryer atmosphere. 



II. The effect of placing the death-feigning animal in water: 

 The death feint in some aquatic invertebrated animals can often 

 be terminated by placing them in water. Holmes (13, p. 162) 

 finds that "in Ranatras of five days old or less the death feint 

 often persists for a time after they are placed in water." In the 

 mature Ranatra (13, p. 162), however, "the moment the* insect 

 is placed in the water the death feint entirely disappears." 



The death feint of Belostomas often ends suddenly when the 

 insects are thrown into water ; frequently, however, the bugs bob up 

 to the surface of the water and continue to feign there. Those 

 specimens, feigning on the surface of the liquid medium, also 

 showed a wide variability in the duration of the death feint, 

 as was the case with those which feigned upon a solid sub- 

 stratum. While some individuals came out of their inert state 

 almost immediately, others would remain motionless at the 

 surface film for a few seconds and then begin to" swim about 

 very actively, while still others feigned for a much longer time. 

 Occasionally, those insects, which feigned for some time at 

 the surface of the water, first gave an outward sign before coming 

 out of the feint. The proboscis groped about in the water and 

 the legs were gradually sprawled apart. The hemipteron would 

 remain with its legs in this position from a few minutes to a con- 

 siderable length of time. Next, one would sometimes notice 

 the swimming legs make a few weak strokes. Probably the 



