908 The American Naturalist. [October, 
uals of the same or of different species, without regard to sex, is 
not uncommon among birds and in mammals, and is probably an 
outgrowth of the maternal and sex instincts. The affection of 
many of the Mammalia for their human masters is well known, 
although this sentiment differs greatly in degree in individuals 
o fthe same species, as, for instance, in the dog. 
Shame is evidently experienced by some of the Mammalia, 
especially by monkeys and by dogs. This affection is an antici- 
pation of the ethical sense, a quality which will be considered 
under the head of the intelligence, further on. 
Jealousy is strongly developed in Mammalia, especially among 
dogs. It is quite as obvious among these animals as among hu- 
man beings. An illustration of jealousy on the part of a chim- 
panzee used frequently to amuse the visitors to the Zoological 
Garden of Philadelphia. It was the custom of the keeper to feed 
a pair of these animals together with bread and milk, using a 
spoon. One sat on each side of him with an arm placed about 
his waist, and the keeper fed them alternately. At times he would 
intentionally neglect one or the other of them. As this continued 
the neglected animal showed his displeasure by pouting the lips, 
and finally he would rush from the side of the keeper, and throw- 
ing himself on his back would give way to a burst of jealous 
rage. He kicked his feet, threw straw into the air, and screamed 
vigorously, the whole proceeding resembling what one sometimes 
sees in a spoiled child. On the offer of renewed attention from 
the keeper, the chimpanzee was pacified, and took his original 
position with great satisfaction. 
Another and older chimpanzee confined in the same garden 
became paralyzed in the posterior limbs. Two lemurs (L. catta.) 
were given to it for company. Their playful activity was at times 
a source of irritation to the chimpanzee. Her grimaces and 
cries of rage at these harmless creatures were laughable, and her 
impotent attempts to dislodge them from their hold above her, by 
shaking the wood-work on which they rested, was an exhibition 
of passion which was quite ridiculous. 
Admiration for brilliant or i pressive colors or forms is evidently 
experienced by the vertebrate animals. It is probably present 
