1890) 7 The Evolution of Mind. 913 
Gallina: and some of the snipe family squat on ground, which 
they resemble in color, until danger has passed. An ingenious 
device is employed by certain green snakes of North America 
(Liopeltis vernalis). They burrow under the earth, and then per- 
mit the head and a few inches of the body toemerge. This por- 
tion of the body is held rigidly vertical, and is not distinguish- 
able on a cursory view from the shoots and stems of green vege- ` 
tation which surround it. 
Fear sometimes stimulates an animal with the desire to inspire 
fear in return. I once observed this in the conduct of a Hetero- 
don platyrhinus (hog-nose adder), which was kept in a cage with 
a water-snake (Natrix sipedon) and a copperhead (Ancistrodon 
` contortrix). Both of the harmless species were evidently greatly 
frightened on the introduction of the copperhead into the cage. 
The water-snake sought the lowest spot in the sand on the bot- 
tom of the cage, and coiling up kept close to the ground, not 
even raising his head. The Heterodon, on the contrary, inflated 
his long lung, swelling the greater part of his body into the 
form of a cylindrical bladder. He at the same time extended 
the anterior ribs, so that this part of the body resembled the thin 
blade of a paper-cutter. He then plunged his nose into the 
sand, and covered the top of his head with as large a pile of that 
substance as it would carry. In this disfigured condition he 
paraded slowly about the cage in front of the copperhead. The 
latter moved but little, and showed no disposition to provoke a 
quarrel with its singular companion. The Heterodon platyrhinus, 
when disturbed by man, throws itself into vigorous contortions, 
spreads the anterior ribs, and opens the mouth widely, after 
the manner of a venomous snake. The habit of erecting, under 
the stimulus of fear, the feathers and hair in order to increase the 
apparent size of the body, and so inspire fear, is common among 
birds and mammalia. The artificial ferocity of many monkeys, 
` while under the influence of the very opposite emotion, t.e., fear, 
is often very amusing. Monkeys generally look away from a per- 
son whom they wish to attack, so as to throw the latter most 
completely off his guard. 
(To be continued.) 
