DEVELOPMENT OF THE ANTENNA'! OF TERMITES. 273 



instead of XX-jointed because (16) abjuncts as an orphan 

 joint and leaves III composed of (0000 +17). The XIX- 

 jointed soldier expression (6) is regarded as a development 

 through stage M to Nb parallel to that of the imago. Should 

 no fission take place in III at the stage M the XVIII soldier 

 expression (c) will result. The XVII expi-ession {h) is a 

 development through stage J to JM, and an XVIII expression 

 may be derived through J and JJf to JNh by the separation 

 of (16) from III as in the form represented by (/). 



(4) Termes natal ens is Havlland. Fig. 8, a-e. 



Antennal Index. — ImagoXIX (pseudo-XX) ; major woi^ker 

 XVIII, XVII; minor worker XVII; major soldier XVII; 

 minor soldier XVII. 



The antennal index is based upon the examination of so 

 many nest series and so many antennae that I have long since 

 neglected to keep a record of them. Without doubt several 

 topographical forms of natal ens is are included in this 

 review all of which are sufficiently distinct from bellicosus; 

 two at least would be regarded, taxonomically, as individual 

 species. 



The imago antennse are uniformly XlX-jointed except for 

 some exhibiting a very decided notch in joint III, fig. 8, a^ 

 illustrating the evolution of this organ from one of XX joints. 

 A precisely similar condition is also to be met with in the 

 imago antennas of T. bellicosus. The discovery of soldiers 

 of the last-mentioned species with XIX organs, as detailed in 

 the foregoing section, coupled with the agreement between 

 the development of the antennas of T. natalensis and 

 T. waterbergi, is sufficient evidence for the homologising 

 of all the soldier and worker antennge of T. natalensis with 

 those of the imago as in fig. 8, a-e. 



Development. — The antennal expression of the larva ab 

 ovo is the same as in T. waterbergi, one of XII segments 

 with III bilocular (stage C, PI. XV). The development and 

 changes of the formative III are also precisely the same. 



