584 Dale. — Observations on Gymnoascaceae. 
repeatedly and form round the coil a dense mass of asco- 
genous hyphae (Fig. 49). Besides the ascogenous hyphae 
a few vegetative hyphae seem to grow out from the base 
of the coil, as in G. Reessii (Fig. 50). 
The development of the asci and ascospores seems to take 
place exactly as in G. Reessii , except that the occurrence of 
a large vacuole is not so constant. But the exceeding minute- 
ness of the asci and their spores makes the details of their 
development very difficult to follow, even with the highest 
available magnification. For the same reason the behaviour 
of the nuclei is difficult to observe. There is no doubt, how- 
ever, that the conjugating cells about the time of fusion both 
contain numbers of small nuclei (Fig. 45), whereas in the 
youngest stage, as in G. Reessii , there seems to be but one 
large nucleus in each cell (Fig. 43 a). 
The young asci also appear at first each to have one large 
nucleus, with a nuclear zone, in the dilating end of the asco- 
genous hypha (Fig. 51 a). This evidently divides into two 
(Fig. 51 b), then into four, and finally into eight (Fig. 51 0 , 
which are small after division, but increase in size when the 
divisions are all completed. Certain slender hyphae, filled at 
the apex with small nuclei, are apparently vegetative hyphae 
like those occurring in G. Reessii (Fig. 51 e). As is the case 
in G. Reessii , the remains of the empty coil may be seen within 
the mass of ripening asci (Fig. 52). Besides ascospores this 
species also produces abundant oidia. Each colony produces 
either oidia or ascospores, or both. 
With the naked eye the ascogenous parts of the colonies 
are of a chalky whiteness and consistency, because the dense 
masses of minute asci cover up the small cushion of delicate 
hyphae which is first formed. In cultures grown from single asco- 
spores each colony forms a white circular mass, a centimetre or 
more in diameter, which usually produces asci at the centre and 
oidia round the periphery (Figs. 53 and 54). The hyphae form- 
ing the oidia are usually erect and branching, and form masses 
which, to the naked eye, are somewhat flocculent. 
As in G. Reessii and G. setosus the habit of the colonies 
