198 E. A. ANDREWS 



Some of the nests are too large to be put into a barrel and 

 too heavy to be lifted by a man. One, i-| feet high and 2^ feet 

 on the side of the rather quadrangular base, weighed 43 pounds, 

 dry, without the contained termites and food store. When 

 broken into, the nest appears like a sponge of dark material 

 which is brittle but very tough and heavy enough to sink in 

 water. 



The newer parts of the nest are lighter colored and the older 

 darker and more dense with less air space. In form the nest is 

 globose or conical or more rarely spindle-shaped with the base, 

 or one side, or the centre, applied to the tree trunk, branch or 

 fence post, or the stone or ground, that is the substratum. The 

 part near this substratum is the oldest and the most compact. 

 While at first sight the passageways seem without any system 

 they reveal more or less the plan of consecutive layers from the 

 older part to the surface, at least in many nests and in some 

 regions of the nest. But the presence of foreign objects, branches, 

 leaves, etc., in the interior of the nest where it has been gradually 

 built over these neighboring objects often makes the interior 

 very irregular. 



The labyrinths in the nest are often about 7 mm. in diameter 

 with walls J mm. thick in all the newer parts of the nest ; but the 

 passageways are of very changeable diameter and shape and 

 they communicate so frequently as to appear a mere sponge 

 work. It is difficult to thrust in a straight needle more than 

 30 mm. without meeting a wall. In older parts of a nest we may 

 break open chambers 30 by 40 mm. by only 7 mm. deep which 

 may send out several branching passages 7 mm. wide on that 

 same level. The walls here may be ^ to i mm. thick. The most 

 completely lamellated parts of nests are made up of concentric 

 stories about 7 mm. deep with walls that are i to ^ mm. thick. 

 In each story the passageways take on the character of curved, 

 shallow chambers that may be 30 to 50 mm. on the level but only 

 7 mm. deep. The floor of one is the ceiling of another and such 

 plates may be isolated as sheets of the dark papier mache mate- 

 terial of the above thickness and expanse. But such large ap- 

 proximately level pieces are quite exceptional, the usual frag- 

 ment of the nest is always abruptly curved and of little extent. 



In some most dense parts of nests the passageways may be 

 reduced to 3 and 4 mm. in diameter while the walls are thickened 



