AFFINITIES AND GENEALOGY. 167 



least to a large extent, if man is the co-descendant with 

 other mammals of so-me unknown and lower form. 



Some naturalists, from bein^ deeply impressed with the 

 mental and spiritual powers of man. have divided the whole 

 organic world into three kingdoms, the Human, the Animal, 

 and the Vegetable, thus giving to man a separate kingdom.* 

 Spiritual powers cannot be compared or classed by the nat- 

 uralist; but he may endeavor to show, as I have done, that 

 the mental faculties of man and the lower animals do not 

 differ in kind, although immensely in degree. A difference 

 in degree, however great, does n.ot justify us in placing man 

 in a distinct kingdom, as will perhaps be best illustrated 

 by comparing the mental powers of two insects, namely, 

 a coccus or scale-insect and an ant, which undoubtedly be- 

 long to the same class. The difference is here greater than, 

 though of a somewhat different kind from, that between 

 man and the highest mammal. The female coccus, while 

 young, attaches itself by its proboscis to a plant; sucks the 

 sap, but never moves again; is fertilized and lays eggs; and 

 this is its whole history. On the other hand, to describe 

 the habits and mental powers of worker -ants, would 

 require, as Pierre Huber has shown, a large volume; I may, 

 however, briefly specify a few points. Ants certainly com- 

 municate information to each other, and several unite for 

 the same work, or for games of play. They recognize their 

 fellow-ants after months of absence, and feel sympathy for 

 each other. They build great edifices, keep them clean, 

 close the doors in the evening, and post sentries. They 

 make roads as well as tunnels under rivers, and temporary 

 bridges over them, by clinging together. They collect food 

 for the community, and when an object, too large for 

 entrance, is brought to the nest, they enlarge the door, and 

 afterward build it up again. They store up seeds, of which 

 they prevent the germination, and which, if damp, are 

 brought up to the surface to dry. They keep aphides and 

 other insects as milch-cows. They go out to tattle in regu- 

 lar bands, and freely sacrifice their lives for the common 

 weal. They emigrate according to a preconcerted plan. 

 They capture slaves. They move the eggs of their aphides, 

 as well as their own eggs and cocoons, into warm parts of 



* Isidore GeofTroy St. Hilnire gives a detailed account of the posi- 

 tion assigned to man by various naturalists in their classifications; 

 "Hist. Sat. Gen./' torn, ii, 1339, pu. 170-189. 



