6 H. MARSHALL WARD, 



and hints at their possibly serving as reproductive bodies much as the 

 Oiclium forms of Erysiphece : since he worked with dried specimens, 

 however, this question could not be decided. 



Bornet remarks that the mycelium on the upper side of many leaves 

 are sterile, while those below and protected from the direct rays of 

 the sun alone support perithecia : this is certainly not true for the 

 species examined by me, and, indeed, I cannot determine any difference 

 between the upper and lower mycelia in this respect. Those on the 

 upper surface seem quite as productive of spores, &c, as those below, 

 and in many cases — e. g., those Meliolce so common on Memecylon — ; 

 the mycelium vegetates almost exclusively on the upper surface, and 

 is quite fertile there. 



Besides the short pyriform and flask-shaped branchlets described 

 above, the mycelium bears certain stiff, upright, appendages of the 

 nature of setce (see figs. 1, 41, and 8) : these setce spring from the 

 cells of the hyphse at various points in their course, and, from their 

 position and mode of origin, are probably to be regarded, morphologi- 

 cally speaking, as lateral branchlets which become elongated in a 

 direction more or less perpendicular to the plane of the leaf. Such a 

 seta grows very rapidly and soon reaches its limit : the cylindrical 

 cells composing it are relatively longer than those of the hyphae, but 

 resemble them in other respects (the walls being, perhaps, somewhat 

 stiffer and more deeply coloured), and taper above, in the simple types, 

 or become variously branched. 



In most Meliolas the setce are especially aggregated around the 

 perithecia, forming circles of stiff radii springing from what Bornet 

 terms the "receptacle" : they are also developed, however, from various 

 isolated points of the mycelium bearing no direct relation to the fruit- 

 bodies. 



The forms of the setce vary from a simple, upright or curved filament, 

 to structures branched like antlers, trifurcate, twisted, &c, at the tip 

 (cf. fig. 8 and Bornet's figures x ) : Bornet has made use, of these details 

 in classifying the formal species, and although it is doubtful 

 whether the more similar type's are constant, there can be no objec- 

 tion to their use much in the same manner that the appendages of 

 Erysiphece, &c, are used to distinguish the forms of that group. 

 Bornet regards the origin of the setce at points on the mycelium as 

 marking out places where new perithecia are to be developed : I cannot 

 1 Loc. cit., plates 21 and 22, figs. 6, 15, 16, &c. 



