'I' ABLE OF CONTENTS. 



I'll. \ITER XVI. 

 THE 1 1 AKVKSTING ANTS. 



PAGE 



I. The Origin and Development of the Harvesting Habit .... 267 

 II. Early Observations 268 



III. Observations of European Harvesters by Moggridge, 



Forel, Andre, Emery and Others 269 



IV. The North African Harvester O.ryopoinynnc.v saiitscliii . . 273 

 V. The Asiatic Harvesters Pheidole, Holcomyrmex and Phei- 



dologeton 275 



VI. The Australian Harvesters Pheidole lonyiccps and Mcra- 



noplus 276 



VII. The American Harvesters (Solcnopsidii and Myrhricii) . . . 278 



I. S'olenopsis gcininata, the " fire ant." 2. The Genus Pheidole. 

 3. The Genus Mcssor. 4. Ischnomyrmex cockerelli and 

 albisetosus. 4. The Genus Pogonomyrmex. (a) Char- 

 acterization, Range, and Classification, (b) Pogonomynncx 

 imbcriculus, etc. (c) The Florida Harvester, etc. (d) 

 The Texan Harvester and the "Ant-rice" Theory. (c) 

 The Marriage Flight of the Texan Harvester. (/) The 

 Founding of Colonies by P. inolcfacicns. (g) The Occident 

 Harvester. (/O The Stinging Habits of Pogonomynncx. 



CHAPTER XVII. 



THE RELATIONS OF ANTS TO VASCULAR PLANTS. 



I. The Hypothesis of Mutualism between Ants and Plants . . . 294 

 II. Plant Adaptations Apparently Indicating Symbiosis 295 



I. Dwelling-places for Ants. (a) Cavities in Stems. (b) 

 Tubers, Bulbs, Pseudobulbs, Rootstocks, etc. (c) Ascidiae 

 or Bursse of Leaves and Petioles, (d} Spaces between or 

 under Leaves. (c) Thorns. (/) Seed-pods. (</) Galls. 

 2. Food-supplies for Ants. (a) Floral Nectaries. (b) 

 Extrafloral Nectaries. (c) Food-bodies. (d) Bead-glands 

 ("Perldriisen"). (e) Pith and Other Vegetable Tissues. 



III. The Ants Dwelling on Plants 302 



I. The Arboreal Genera. 2. The Habits and Structural 

 Adaptations of Astcca and Pseudomyrma, and their Rela- 

 tions to the Problem. 3. The Relations of Aztcca muclleri 

 to Cecropia adcnopus. 4. The Relations of Ants to Myrme- 

 codia, Hydnophytum and Myrmephytum. 5. The Relations 



