TABLE OF CONTENTS. xix 



PAGE 



of Pseudomynna bicolor to Acacia spharocephala. 6. Other 

 Acacias Inhabited by Ants. /. Other Examples Found in 

 South America. 



IV. Other Relations of Ants to Plants 315 



i. Ants as Seed Distributors. 2. Ant-Gardens. 3. Plants 

 Injurious to Ants. 



CHAPTER XVIII. 



THE FUNGUS-GROWING ANTS. 



I. The Symbiotic Relation between the Fungus-growing Ants 



and Their Fungi 318 



II. Characteristics of the Tribe Attii 319 



III. Review of the Literature 320 



IV. Belt's Observations on Atta ccphalotcs 321 



V. Moeller's Observations 324 



i. The Genus Acromyrmex. 2. The Systematic Position of 

 the Fungus. 3. The Genus Aptcrostigma. 4. The Genus 

 Cyphomyrmex. 



VI. The Source and Nourishment of the Fungus in the Colony. 

 (Observations of Sampaio, von Ihering, Goeldi and 



Huber. ) 329 



VII. The Fungus-growing Ants of the United States 333 



(a) Personal Observations on i. Cyphomyrmex. 2. Myceto- 

 soritis. 3. Trachymyrmcx. 4. Mocllerius. 5. Atta s. str. 



(b) General Considerations. I. Advance in the Fungus- 

 growing Habit. 2. Condition of our Knowledge as to the 

 Origin of the Habit. 



CHAPTER XIX. 



THE RELATIONS OF ANTS TO PLANT-LICE, SCALE-INSECTS, TREE- 

 HOPPERS AND CATERPILLARS. 



I. The Liquid-excreting Insects Attended by Ants 339 



II. Relations of Ants with Aphids 340 



i. Habits of Aphids. 2. Behavior of Aphidicolous Ants. 

 3. The Abdominal Siphons of Aphids. 



