OF CERTAIN TERMITE NESTS. 201 



broad. The hyphae are markedly septate, the septa being 

 sometimes only 5 p apart, and often form oval expansions. 

 From these creeping hyphae arise upright branches of the same 

 diameter, 20-120 it long : they do not however develop any 

 different structure individually, but unite into small groups to 

 produce the " conidial " formation which has been noted by 

 all investigators into the habits of termites (PL XII. B). 



These " conidial " formations are seen all over the comb as 

 small white stalked, or almost sessile spheres up to 1*25 mm. 

 diameter. Few or none are found on the dark brown outer 

 surface when the comb contains larvae, but elsewhere they 

 may be closely crowded as many as 120 to the square centi- 

 metre. In the interior of the comb they are more abundant 

 on the roof and sides of a passage than on the floor. In some 

 cases comparatively extensive tracts are almost destitute of 

 spheres, though the hyphae are present, and in these areas 

 there often occur long narrow bare patches from which the 

 hyphae also have been eaten away. When viewed as opaque 

 objects under a low magnification they appear to be a cluster 

 of spherical conidia on a short stalk. They are largest in 

 combs which do not contain larvae : I have not been able 

 to confirm Holtermann's observation that they vary in size 

 according to the size of the comb and the size of the termite 

 inhabiting it. Combs vary enormously in size in a single nest. 

 The white spheres arise directly from the superficial mycelium 

 by the combination of several of the upright branches into a 

 loosely-built stalk in which the individual hyphae can be clear- 

 ly distinguished. The stalk expands upwards, and at the 

 height of about a millimetre the hyphai separate and bifur- 

 cate repeatedly, each branch ultimately terminating in one or 

 two oval expansions (which may be 60 x 20 /x) on which 

 " conidia " are produced. The head, which was at first oval, 

 is now almost exactly spherical, and the stalk is in many 

 cases hidden by the reflexed lower branches (PI. XVII. B). 



The conidia-like cells are of two kinds : on the exterior 

 hyphae only spherical cells, 20 it diameter, are formed, while 



