SOUTH AFRICAN TKHMITES. 67 



IX. SPECIAL WING STUDIES. 



IXa. HODOTERMES .■^pj^- 



PI. A"II, figs. 78-84D. 



The wings of various Hodotermes all possess a very 

 similar scheme of venation^ such differences as do occur being 

 chiefly the degree of coarseness in which the ribs are dis- 

 played. At one extreme stands H. karrooensis, fig. 70a 

 (PI. VI), at the other H. viator, figs. 84a. to d (PI. VII). 

 The ribs, in the former species, are not only more gross than 

 those in the latter, but the branching of some, particularly 

 the post-costa and sub-costa, is more ample and the "reticu- 

 lation " more decided. 



The ribs Pst. C, 8c. , R., Ps. M., Cu. and A. are preceded 

 by trachepe. The costa may not be so strongly developed as 

 the radius, especially towards the apex of the wing, and its 

 continuation around the inner margin is much obliterated. 

 It extends along the outer edge of the wing-stump, but is 

 attenuated or thinned out at the root of the wing. 



The post-costa forms the anterior articulation of the wing 

 and extends as a strongly chitinised ridge through the wing- 

 stump into the lamina. It is connected with the costa by a 

 short curved branch or strut, which occurs outside the line of 

 fracture in the fore wing, and inside of it in the hind, and is 

 preceded by a branch of the post-costal trachea, x., fig. 78 

 (PI. VII). 



The pseudo-media unites in the hind wing with the radius 

 well outside the line of fracture, fig. 70b (PI. VI). In only 

 one wing has a deviation from this rule been found, and in 

 this, fig. 71 (PI. VI), its union with the radius took place at 

 the line of fracture. In the fore wing, the pseudo-media 

 enters the wing-stump, there its base merges into the bases 

 of the radius and cubitus, fig. 70a (PI. VI). 



The anal of the hind wing may be described as a prolonga- 

 tion of the somewhat pyriform anal lobe of the stump ; it 



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