1899. The Habits of American Cicindelidæ. Proc. Davenport Acad. Sci., Vol. VII, pp. 206-228.

Yerkes, R. M.

1904. Space Perception of Tortoises. Jour. Comp. Neurol. and Psychol., Vol. XIV, pp. 17-26.

Yoakum, C. S.

1909. Some Experiments upon the Behavior of Squirrels. Jour. Comp. Neurol. and Psychol., Vol. XIX, pp. 541-568.

IX. THE CONTINUOUS PROCESS OF ADJUSTMENT BETWEEN THE ENVIRONMENT AND THE ANIMAL, WITH SPECIAL REFERENCE TO OTHER ORGANISMS

The Dynamic or Process Relation of Animal Associations and Aggregations

1. The Struggle for Existence.

2. The Dynamic Relations of Aggregations and Associations, with Special Reference to Animal Associations.

a. The Relation of Animals to Pollination and to Plant Galls.