G. H. F. Nuttall 
183 
Sham Death, and the Signs of Death in Lice. 
Sham death is observable in lice that have been immersed ib water 
for some hours 1 , or in insects that have been temporarily narcotized 
by exposure to the vapours of essential oils, benzine, petrol, ether, etc., 
for a period insufficiently long to kill them. The insects may sham 
death for several hours if the exposure has been sufficiently prolonged; 
this has led to error in judgment as to the efficacy of various remedies. 
Certain authors rely upon the stoppage of digestive peristalsis 
(Widmann, 18. vm. 1915, p. 290), the cessation of the embryo’s move¬ 
ments in the egg (Wulker, 1915, p. 628), and the shrinkage of the eggs 
as signs of death, but such signs may be misleading. I have seen 
peristalsis recommence, and embryos resume their movements after 
hours of inactivity, and considerable shrinkage of the eggs may occur 
without death taking place. ' A certain amount of shrinkage invariably 
takes place a couple of days before the larvae emerge. For practical 
purposes much clearer evidence of death is required than that here 
mentioned. 
A certain sign of the approach of death is afforded by the larvae 
and adults turning pink and then red in colour owing to the escape of 
blood or haemoglobin into the coelomic cavity. Under ordinary 
conditions this appearance is due, in my opinion, to rupture of the 
intestine from overfeeding; I have so far only observed it in lice which 
have been fed but twice a day, and have consequently gorged them¬ 
selves to excess. In the laboratory, we have seen lice turn red within 
a few minutes of having overfed. 
Sikora '(vm. 1915, p. 533) remarked that lice which turn red did not 
feed, and that lice kept at 20° C. often turned red; she cites Halberkann 
as having frequently observed this condition in lice experimented upon 
with insecticides, and she believes that it is due either to altered meta¬ 
bolism, the haemoglobin escaping into the coelom, or to the action of 
a tyrosinase on chromogen. Muller (1915, p. 54) also states that the 
turning red is due to the effect of poisons. Bacot (n. 1917) attributed 
the turning red of a female to the sexual act. I have seen gorged lice 
kept at 12° C. gradually turn red after a few days whilst they continued 
living, and in such cases the phenomenon is probably due to the trans¬ 
fusion of haemoglobin through the gut wall of the slowly dying insect, 
the condition being doubtless comparable to that following the action 
1 Sham death was first observed by Lazia (1915, p. 301, according to Muller, 1915, 
p. 54). 
