No. 559] SHORTER ARTICLES AND DISCUSSION 431 



I have seen a termites' nest excavated for this purpose to a 

 depth of five feet, but further than this I have no evidence as to 

 the depth of their work. Laterally their passageways seem to 

 underlie vast areas, as it is seldom that one can put a wooden box 

 on the ground so far from a foraging route that the insects will 

 not find it out in a few days. 



The Stanleyville Region. — There are a great many termite 

 nests in the forest country around Stanleyville, but they are of 

 a slightly different character from those previously described. 

 The newer portions of the Stanleyville nests, instead of being 

 chimney-like structures, resemble the white ants' nests of Brazil 

 as described by Dr. Branner. They are built of earth, in many 

 cases containing grains of sand and masticated vegetable matter. 

 This is built on in a plastic condition leaving no external open- 

 ings and hardens on exposure. 



The walls of these nests wash down, forming rounded mounds 

 and in time form mounds similar to those described from the 

 Loami valley. 



A general idea of the age of the nests can occasionally be ob- 

 tained in this region from the size of some of the trees which are 

 found growing on the mounds. Fig. 2 shows the stump of a 

 camwood tree which grew on a mound near Stanleyville. Cam- 

 wood is a hard, red wood much resembling rosewood in appear- 

 ance, and this stump is thirty inches across the top. 



Along the Kami River. — Still another variety of termite nest 

 is found in the drainage of the Kasai river. This variety does 

 not show the aversion to poorly drained localities that was noted 

 in the Loami valley, but seems rather to prefer the clayey soil 

 of the lowlands to sandstone hill areas. 



The nature of the above-ground portions of the nests is illus- 

 trated in Figs. 3 and 4. While these termites have extensive 

 underground foraging trails similar to those mentioned above, 

 there seems to be much less of the nest below the general surface 

 of the ground. 



The live part of the nest is a dome-shaped chamber at or 

 slightly above the surface of the ground. This chamber ordi- 

 narily has walls about six inches thick of firmly cemented sandy 

 clay and enclosing a cellular mass consisting mostly of masticated 

 vegetation. Fig. 3 shows one of these chambers which has been 

 broken open. It also shows a portion of the cellular mass within. 



The largest of these nests reach a height of about twelve feet 



