eee ee ee Nee 
1897] ZYGOMYCETES, SVNCEPHALASTRUM AND SYNCEPHALIS 7 
is formed. While these changes are taking place the tip of the 
sporangial hypha undergoes a somewhat similar modification. A 
cap appears within it (fig. 39) which is at first composed of non- 
stainable material like that of the intermediary zones, but which, 
like the latter, soon shows a distinction between a stainable and 
non-stainable portion (fig. go). This terminal cap eventually 
shares a fate similar to that of the intermediary zones, becoming 
deliquescent and leaving the terminal spore of the row everly 
oblong like the rest. 
Having had abundant material of this species growing in a 
fresh condition it was possible to verify many times the course of 
development just described, the correctness of which was further 
substantiated by the examination of a second species subsequently 
described as S. pycnosperma. The sporangial hyphe of this species 
are far larger than those of the form last described, although the 
intermediary zones are relatively narrower. The process by which 
the latter arise is exactly similar to that of the African form, 
except that the stainable portion of the zone is proportionately 
less well developed, forming finally a thin ‘separation disk” 
( fig. 36 6) which, as the spore matures, loses its power of absorb- 
ing stain and is converted into a refractive oily substance. That 
portion of the zone, moreover, which was at the outset unstain- 
able persists as the spore matures, being converted into a thick 
wall firmly united to that of the spore and barely distinguishable 
from it ( fig. 38a, in which this distinction is much exaggerated), 
and it is the persistence of this area (a) which gives to the ripe 
spores their peculiar form ( figs. 34, 37,38). The same differ- 
ences may be noted in the phenomena which occur at the apex 
of the sporangial filaments, the process being even more clearly 
marked than in the species last described. The portion of the fila- 
ment separated above the terminal spore is here so large that it 
has the appearance of a definite small cell; and as the spore 
matures it passes through the same changes which have just 
been described as characteristic of the separation zones. The 
portion which is at first stainable becomes converted into oily 
material, and disappears together with the portion of the wall of 
