124 THE NATURALIST IN AUSTRALIA. 
writer’s mind, with reference to the circumstance that, by being constructed with 
this orientation, their larger surfaces present the least possible direct exposure 
to the meridianal rays of the tropical sun, and in consequence absorb and retain 
interiorly a minimum amount of solar heat. 
The author is beholden to Mr. Paul Folsche for the photographs of yet 
another form of White Ant termitarium, reproduced in this volume. It occurs 
also in the neighbourhood of Port Darwin, and probably represents the most 
colossal example of these remarkable insect habitations that is to be found in the 
Australian Continent. The architectural plan of this variety may be most appropriately 
designated the “Columnar.” The altitude of the highest of these termitaria observed, 
Plate XXII, fig. A, is no less than eighteen feet, as may be verified by the figures 
of the man, horses, and vehicle standing beside it. In common with the pyramidal 
type of termitarium belonging to the Cape York Peninsula district of Northern 
Queensland, previously described, this columnar form is associated with strong ridges 
or buttresses, which, extending throughout the length of the lofty column, must add 
materially to its rigidity and strength. It will be of interest to ascertain whether 
any remarkably large species of White Ant is the fabricator of these tower-like 
structures. Although unable to produce any direct evidence on this subject in the 
present volume, the writer has been informed by Mr. Froggatt that its constructors 
are most probably referable to the genus Eutermes. 
In addition to the remarkable descriptions of White Ant habitations now 
enumerated, there are a number of Australian Termites awaiting identification and 
classification that either construct smaller and architecturally insignificant termitaria 
or which, erecting no mound whatever, are purely miners, living in decaying wood 
or subterranean chambers and galleries, whence they extend their depredations to 
remote distances. Among the former category, irregular mound-shaped termitaria 
some two or three feet high, probably constructed by distinct species, may be met 
with at a considerable distance south of the tropic of Capricorn, on both the Queensland 
and Western Australian sides of the Island-Continent. In the former instance they 
may be referred to as being abundant in the neighbourhood of Brisbane, and in 
Western Australia as extending as far south as Pinjarrah and Bunbury, in about 
latitude 33°. It frequently happens that birds of various species excavate holes 
and build their nests within these smaller termitaria. A White-breasted Kingfisher, 
probably Halcyon sanctus, thus constructs its nest in those in the southern districts 
of Western Australia. In similar irregular heap-like termitaria in the neighbourhood 
