of dead megaccphaJa. which had been carried c)ut of the nests 

 by the survivors. These fatalities apparently always took 

 place dnrino- cool rainy nights, and the heaps of dead were 

 only fonnd at the entrances of nests located in the furrows 

 between the cane rows. The indication is that the ants were 

 overtaken by a flood of water, while in a chilled condition, 

 otherwise we should expect dead in the nests on the ridges 

 as well as in the furrows. An experiment was tried of flood- 

 ing a nest for a brief period during the day, but apparently 

 no fatalities i-esulted, for as soon as the water subsided the 

 workers began carrying the brood to a drier location. 



Dr. Perkins (11)18) mentions low-lying localities, along the 

 coast, which from excessive dryness and other causes, the 

 Plieidole is unable to occupy, at any rate ])ermanently. A good 

 example of such a locality is to be found just beyond Koko 

 Head crater, here on Oahu. Going over into this valley, a 

 marked change in the insect-fauna is to lie noted. While 

 megacepliahi is the dominant ant on the lT(Miolulu-side of the 

 crater, there is scarcely a trace of this s])ecies on the opposite 

 side, which is an extremely dry and windswept area. Several 

 other ants have, however, adapted tluMnselves to these diffi- 

 cult conditions. IJoth Prenolrpis loiu/lroiiiis and the fire 

 ant (Solenopsis gemlnata var. rufa) are there in abundance. 

 The first species favoring the region of coral sand, and the 

 second the alluvial soil, further back from the shore, in accord- 

 ance with its agricultural habits. 



It is interesting to recall that thc^se are the same species, 

 recently exterminated hy iner/arcphdld. in the vicinity of my 

 home, in Palolo Valley. They are certainly drivc^n to the 

 "ends of the cai'th'''' in a region such as we find beyond 

 Koko Head. 



Tn favoral)le regions, such as we find in any of our humid 

 valleys, l\ iiicgdcephala is exceedingly abundant. These ants 

 make use of every stone for a roof, and tlie large cracks in the 

 volcanic soil, whicli form during the di'v season, furnish them 

 ready-made chambers to a considoral)le de])tli. Xaturally, 

 heavy rains are unfavorable to them in this spongy soil, and 



