1890.] The Evolution of Mind. 1003 
intelligence. Some of them anticipate the arrival of deer, which 
run ina circle, by cutting across its diameter and reaching a point 
in advance of them. In the same way foxes show remarkable 
intelligence in their endeavors to escape from dogs in pursuit. 
They double on their own tracks, and run in water to destroy 
and confuse the scent. These actions show reasoning capacity 
of a very respectable order. 
The Hymenopterus insects display the most remarkable 
powers of self-preservation and protection through social organi- 
zations. This intelligence was probably reached at some early 
geologic age, and it has been followed by remarkable conse- 
quences, both to themselves and to other members of the animal, 
and not less to the vegetable, kingdom. It may be truly said that 
man himself has produced no such important constructive effects 
on other organic beings, although his destructive effects have 
been probably greater. In the first place, the habits of many of 
the order in seeking their food in flowers have probably been the 
active agency in determining the forms of many of the latter, as 
well as of developing the nectariferous glands and increasing 
their secretion. This view was suggested by Müller and myself 
at about the same time, and has been elaborated by Henslow in 
one of the volumes of the International Scientific Series. In the 
next place, a number of animal types have been called into exis- 
tence through the food and protection offered by the domestic 
economy of the ants. Among Vertebrata we have three families 
which live in ants’ nests, all of which have become blind or nearly 
so, and two have lost their limbs, through the adoption of their 
parasitism on ants. Such are the Cæciliidæ (Batrachia), Amphis- 
baenidae (Lacertilia), and Typhlopida (Ophidia). Then many 
birds (Formicariide) live on ants and Termites, and two families 
of Mammalia, the Myrmecophagide in South America, and the 
Orycteropodidide in Africa. Thirdly, the ants have domesti- 
cated numerous species of insects which they use for their secre- 
tions and for other purposes. In Europe about one hundred 
such species are known. The slave-making habits of various 
ant species are well known. This habit has been so long existent 
in certain species that the latter cannot exist without the aid of 
