1980] 
Thome — Nasutitermes 
239 
ROYAL CELL 
SOFT CARTON, LARGE GALLERIES 
HARD CARTON, SMALL GALLERIES 
Figure 3. Photo of the interior of a small N. ephratae nest. The thin exterior 
envelope has been removed. 
sS0.5 cm). This tough layer protects the thin internal carton and is 
probably an excellent defensive barrier against vertebrate predators. 
The smooth surface covering on the outside of an N. ephratae 
nest encases the dense layer of carton but unlike N. corniger nests, it 
is not attached to the internal carton at the terminus of each gallery. 
Rather, the surface layer is a “superficial envelope” (Noirot 1970). 
This envelope is easily removed in large sections. Inspection of a 
piece of the envelope reveals tiny perforations over the entire 
surface. (Beaumont (Dudley & Beaumont 1889a) noticed small 
‘apertures’ in the exterior carton of N. corniger nests.) It is possible 
that these holes function in air exchange and thermoregulation 
within the colony. 
The relationship between nest volume (estimated using the formu¬ 
la for an ellipsoid) and weight is different between N. corniger and 
N. ephratae (based on non-overlap of the 95% confidence limits on 
the slopes of the principal axes [See Figures 4 and 5] and an analysis 
of variance on the ratio of nest volume: weight indicating that 
differences between species are significant at p< 0.01). On average, 
N. ephratae invests less weight in carton per unit volume of nest. 
