1912] Conotrachelus Nenuphar Herbst 395 
successively for a period of greater length than two hours, 
fifty-three representing the largest number of feints successively 
produced in a single individual. The feints, after the first 
several, tended to show a decrease in duration, some of them 
continuing for only a few seconds. Finally the curculio refused 
to feign longer, no matter how treated, and in many cases made 
strenuous efforts to fly away. 
The muscular system of the insect, while in the death feint, 
is in a tensely contracted condition. When held in a pair of 
forceps by the tip of one tibia, the entire body may be held out 
horizontally without signs of bending or movement on the part 
of the curculio. After a short time, however, the weight of the 
body causes a gradual relaxation of the’ leg muscles, and the 
animal is inclined downwards. Holmes (7) found the same 
thing to hold true in Ranatra, and says: “It is as if aman were 
seized below the knee and held out straight, face upward, 
without causing the knee to bend, only the legs of a Ranatra 
are several times more slender than those of the most attenu- 
ated of the human species, and the muscular tension which the 
insect maintains must therefore be intense.’’ Undoubtedly, 
the acclimatisation of the insect to the extent that failure to 
respond with the death feint occurs after several successive 
periods of it have been passed through is to be explained in 
part at least as due to the muscular fatigue resulting from this 
rigidly contracted condition. 
Effect of Temperatures on the Death Feint. 
According to DeGeer (3), from his work on a small timber- 
boring beetle, Anobrium pertinax, “‘you may maim them, pull 
them limb from limb, roast them alive over a slow fire, but you 
will not gain your end; not a joint will they move, nor show by 
the least symptom that they suffer pain.’’ In order to deter- 
mine whether such a condition held in Conotrachelus nenuphar, 
many feigning specimens were placed on a thin piece of glass 
and gradually heated over the flame of an alcohol lamp. Though 
this experiment was repeated many times, the insects without 
a single exception, recovered activity as soon as the glass 
became heated. Individuals with the abdomen removed, 
others consisting of only the head and prothorax, and still 
others with all of the appendages removed, were placed in the 
