HOTSON. — CULTURE STUDIES OF FUNGI. 271 



Tlio lateral walls of those basal cells adhere (irmly to each other and 

 the cells become incorporated into the bulbil. 



Figures 11-15, Plate 6, illustrate the early stages in the develop- 

 ment, and Figures 14 and 15 show the formation of the .spherical 

 cells at the center, around the initial cell or cells, while Figure 16 

 r(>i)resents a little later stage, which is composed of small hyaline cells 

 with very indistinct walls and forming almost a spherical Ixxly with 

 few, if any, cells projecting beyond the others. About this stage, or 

 usually a little later, it would appear that the bulbils cease to form 

 new cells, or, if any, very few, and that the further increase in its size 

 is chiefly due to the enlargement of the indi\idual cells which compose 

 it and which, up to this period, have been small, hyaline, with in- 

 distinct walls. As these cells enlarge, there is quite a strong lateral 

 pressure exerted, which tends to make the walls angular, whjch in the 

 meantime have become more prominent and gradually assumed a 

 brownish tint, that later becomes a dark brown, almost black. As a 

 result of this mode of development, the l)ulbil at maturity has a 

 clear-cut, even margin, without any appendages or sharp projections, 

 nearly spherical in form, except where some cells in the process of 

 enlargement increased faster than others or in cases where two pri- 

 mordia were formed close together and their early branches became 

 intertwinetl, forming an elongated, compound structure. The color, 

 which becomes so deep that even the cell walls cannot be distin- 

 guished, may be bleached out by placing them in potassium hydroxide 

 for a few hours. The mature bulbils (Figure 17, Plate 6) vary in 

 size, usually measuring from 125 to 175 ix in diameter, although occa- 

 sionally some are even larger. 



Bulbil "No. 200." 



This form was obtained from Dr. G. R. Lyman and was originally 

 found l)y Dr. G. P. Clinton in the vicinity of Cambridge, Massachu- 

 setts, on a fragment of an old nevNspaper in a field. In general this 

 species resembles Grandinia in the mode of development of the 

 bulbils, the presence of conidia and the clamp-connections of the 

 hyphae. The bull^ils, however, are much darker and the myceliiun 

 does not form the white, fibrous, radiating strands that are so charac- 

 teristic of Grandinia. 



On gross cultures, especially of wood or horse dung agar, the hyphae 

 mass together in conspicuous papilla-like elevations, which are 

 much more prominent than the fructification of Grandinia. These 



