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



the middle and hind pairs of legs are held backward below the 

 abdomen, the middle pair being held just within the hind ones. 

 While in this position, the posterior pairs of legs are bent at the 

 tibio-femoral joint, the middle pair but slightly, the hind pair 

 considerably more, so that its tibiae are usually crossed. 



4. The condition of the muscular system while in the death feint: 

 Verworn (27) has called attention to the extreme muscular 

 tension under which various vertebrated animals labor while in 

 the so-called hypnotic state. Holmes (14, p. 183) found that 

 young terns, inhabiting the island of Penikese, do not show 

 this tetanic contraction of the muscles while in the death feint. 

 He writes, "you may pull them about, stretch out their legs, necks, 

 or wings and place them in the most awkward positions, and 

 they will remain as limp and motionless as if really dead." Other 

 birds, however, labor under a muscular strain while feigning 

 death or while in the so-called hypnotic state. Wrangle (4, 

 P- Z^z) gives the most curious case of apparently true simulation 

 of death of the geese which migrate to the Tundras to molt, and 

 which are then quite incapable of flight. He says that they feigned 

 death so well "with their legs and necks stretched out quite stiff, 

 that I passed them by, thinking they were dead." Verworn (27, 

 p. 29) in his experiments upon the so-called hypnotism of the 

 hen finds, that "Auch beim Huhn ist ferner ein sehr deutlicher, 

 individuell aber verschieden starker Tonus der an der be- 

 treffender Bewegung betheiligten Muskeln zu bemerken." 



,A similar condition of muscular rigidity is quite common 

 among the invertebrated animals. Concerning some amphipods 

 and isopods, Holmes (12, p. 203) writes, "the body is strongly 

 flexed and the legs drawn up into a compact form — a condition 

 that can be maintained only through the exercise of a constant 

 muscular strain." In certain spiders that feign death, Robert- 

 son (23, pp. 412 and 417) describes the "sham-death" as a "com- 

 plete tetanus." The young of Ranatra quadridentata, which 

 are only five days old, Holmes (13, p. 161) claims "could be 

 picked up by one of the slender legs and held out without causing 

 a bend in any of the joints, thus showing that the muscles were 

 in a state of extreme contraction." 



In feigning Belostomas the muscles are also in a state of "ex- 

 treme tetanus." If one attempts to pull the tibia of any leg 

 away from the femur while the insect is feigning death, it becomes 



