330 The Naturalist in La Plata. 
emotion so slight as to be scarcely perceptible to 
the greatest extremes of rage or terror. 
(2) The angry excitement roused in some animals 
when a scarlet or bright-red cloth is shown to 
them. So well known is this apparently imsane 
instinct in our cattle that it has given rise to 
a proverb and metaphor familiar in a variety of 
forms to everyone. 
(3) The persecution of a sick or weakly animal 
by its companions. 
(4) The sudden deadly fury that seizes on the 
herd or family at the sight of a companion in ex- 
treme distress. Herbivorous mammals at such 
times will trample and gore the distressed one to 
death. In the case of wolves, and other savage- 
tempered carnivorous species, the distressed fellow 
is frequently torn to pieces and devoured on the 
spot. 
To take the first two together. When we con- 
sider that blood is red; that the smell of it is, or 
may be, or has been, associated with that vivid 
hue in the animal’s mind; that blood, seen and 
smelt is, or has been, associated with the sight of 
wounds and with cries of pain and rage or terror 
from the wounded or captive animal, there appears 
at first sight to be some reason for connecting these 
two instinctive passions as having the same origin 
—namely, terror and rage caused by the sight of 
a member of the herd struck down and bleeding, 
or struggling for life in the grasp of an enemy. I 
do not mean to say that such an image is actually 
present in the animal’s mind, but that the inherited 
or instinctive passion is one in kind and in its work- 
