The Termites of South Africa 95 



AA. Soldiers varying in head measurements, intergrading 

 from small to large. Heads generally wider to much 

 wider than those of workers without distinct transverse 

 ridge. Mandibles coarse. 



B. With pigmented eyespot ; tooth of right mandible 

 with upper edge sloping towards base; tooth of left 

 mandible with upper edge at right angles to margin 



of apical hadius Hav. 



BB. Without pigmented eyespot; tooth of right mandible 

 with upper edge at right angles to margin of apical ; 

 tooth of left somewhat antrose so that upper edge is 

 at less than a right angle to margin of apical. 



transvaalensis Sjost. 



AAA. Soldiers of three distinct castes. Larger soldiers with 

 a pronounced transverse frontal ridge between bases of 

 mandibles behind this ridge a deep depression, in depres- 

 sion a distinct keel okahandjae sp.n. 



Genus MiCROTERMES Wasmann. 

 Subrgenus Microtermes s.str. (sensu Silvestri). 



Concerning the Microtermes herein brought under review I am 

 not yet able to say that any one species possesses two soldier 

 castes. Where there are differences of size the soldiers seemingly 

 intergrade from smaller to larger and one does not see any sharp 

 contrast as between a major and a mmor such as exists with the 

 allied Ancistrotermes. My experience and my collections are still 

 somewhat limited and mainly composed of M. havilandi s.lat. ; 

 therefore the possibility of other species exhibiting major and 

 minor soldiers is not excluded. 



It is quite certain, however, that all our species have two 

 worker castes and the probability is that most have three castes. 

 Where there are three castes, there are two major castes and 

 one minor. All minor workers are characterized by sub-circular 

 heads, the sides and hind margin forming an uninterrupted bend. 

 All major workers have the heads relatively massive, the sides 

 parallel, the hind margin curvate. The larger majors have the 

 head but a shade longer than v^de (almost square) the lesser 

 have the head regularly and plainly longer than wide (elongate 

 rectangular) . 



