62 TERMITE ECONOMY. 



abo\e the level of that surrounding, and in which a termite colony 

 is not established. It may be urged that the termites select the 

 tree clumps and do not originate them, and there is ample eyi- 

 dence to show that the species which commonly inhabit the clumps 

 select the shelter of trees when a\ailable. Thus in many hedge- 

 rows and beneath ornamental trees, particularly about Pretoria, 

 nests occur which are younger than the plants which shelter 

 them. So corrsistent a feature indicates that the termites have 

 selected the sites in which their nests are found. Again, I 

 recently explored an orange grove on the Buzi River, near Beira, 

 in which, beneath the shelter of almost every large tree, motmds 

 from 5 to 8 feet were built up around the trunks, by Hagen's var. 

 mossojiibica of Tcnnes bcllicosits. 



But against this is to be set the fact that the commonest 

 species associated with park-formation in Natal abounds and 

 flourishes far afield in the open savannahs of the high lands, 

 demonstrating at once that it at least is not dependent tipon tree 

 protection. 



An examination of the underground workings of several 

 common kinds has brought to light one or two features of more 

 than passing interest. 



The Harvesting Termites (Hodotermes) familiar as grass- 

 cutters and despoilers of lucerne and oat and wheat crops, were 

 foimd to excavate large subterranean cavities for the storage of 

 their ha}', tilling them with tiers of shelving composed of carton 

 and i)aijer-like material of (|uite a unique form, and possessing 

 quite peculiar architectural features. In the case of two species 

 an additional form or caste was found, the significance of which 

 is at in'esent o1)scure. 



The termite whose nests are recognised by the great air-pits 

 which thev make in the soil, or the chimneys with which these are 

 often surmounted, was found to be a harvester of grass and grass 

 seeds. It jjossesses granaries peculiar to itself and quite apart 

 from the nest and its annexes. These granaries are cavities, 

 empty except for a most complicated system of clay shelving, and 

 remarkable because the har\est of seed is buried away in the 

 surrounding soil. It is well known that many true ants store up 

 seeds in their underground caverns, but this habit has not jjre- 

 viously been recorded for any termite. 



Concerning the commonest of African termites ( Eiitcrmes 

 trinervins) whose rounded mounds are the one striking feature 

 of the landscape in many parts, it was found that wherever these 

 abound the nests are in more or less direct communication with 

 one another. From all radiate permanent uniform roadways, 

 almost exactly an inch below the soil surface, and much of the 

 length of all seems to be the common property of several com- 

 munities. These roadways lead cut to the feeding grounds to 

 which the insects journev each night to collect grass. All along 

 them are small purse-like extensions, remarkably uniform in 

 both shape and size, in which much of the grass is deposited as 

 harvested. This termite is commonh- regarded as a harmless 



