PHIDOLE. 223 



learning from experience that his manner of flight indicates food 

 in sight, have joined him, till a mighty assemblage gets together. 

 So I think it is with ants, but in any interpretation of their 

 actions we are dreadfully hampered by our ignorance of the 

 extent and limit of their senses. 



I varied my experiments in many ways, using various baits. 

 Often my experiments were entire failures, no ant coming to the 

 baits for the whole of the time I could spare to watch by them. 

 At other times the course pursued by the ants seemed entirely 

 contradictory to their usual habits. Once when I had baited 

 with sugar, a from the nest of P. yeensis, mentioned above, 

 found the food quickly, but after tasting she picked up a grain 

 and started off in a direction opposite to that in which lay her 

 nest. After walking about a bit, she dropped the grain and 

 wandered away. The sugar lay a yard or so off the nest of 

 Phidole untouched by them. Four hours afterwards I fouud it 

 being cleared off by a swarm of Tapinoma and one or two giants 

 of Diacamma scalpratum. 



I tried at times to mark with white paint the ants that first 

 discovered my baits. As a rule, or rather I may say with only 

 two exceptions, I succeeded only in frightening the discovering 

 ants, so that they never returned or brought comrades to carry off 

 the food. The twice that I was successful, the marked $ of 

 P. yeensis returned with the first party sent out of the nest. 

 On one of the two successful occasions, I managed to mark, 

 without alarming them out of their senses, two of three ants that 

 had discovered the bait within half a minute of each other, and it 

 was an interesting sight to see the two race each other, each with 

 a grain of sugar, to the nest, apparently trying to see which of 

 them should be the first to communicate the news of food and 

 possibly get all the kudos for it. Both these marked ants sallied 

 forth with the first party sent from the nest. 



Key to the Species, 11. 



A. Club of flagellum of antennae formed of the apical 



three joints, 

 a. First joint of the pedicel with a projection or 



appendix beneath. 

 a'. Metanotal spines clavate and obtuse towards 



apex like the halteres or poisers of a dip- [p. 232. 



teron ? spathifera, 



b'. Metanotal spines more or less acute at apex, 



not clavate. 

 a 2 . Head posteriorly smooth and shining, not ,p. 229. 



sculptured P- lamelhaoda, 



b 2 . Head posteriorly more or less sculptured. 

 a 3 . Frontal grooves for reception of scapes of 



antenna* absent P. 9yi, p. 230. 



6 3 . Frontal grooves for reception of scapes of 



antennae distinct. 



a 4 . Upper margin of node on 1st joint of [.p. 9RU, 



pedicel emarginate P- wahnst, 



