Harper .— Cell- Division in Sporangia and Asci. 507 
later. The process is exactly like that described by myself 
for the cutting off of the conidia in Erysiphe. 
It is interesting that two such modifications in the method 
of cell-division should occur in the same plant. It is possibly 
evidence against the homology of the sporangium and gamete 
that the two are cut off so differently. It may be that the 
two methods are adapted to the difference in the form of 
the cell-wall to be developed in the two cases. Division 
by vacuoles may be better adapted to the formation of 
a dome-shaped cross-wall, while constriction suffices to form 
a plane cross-wall. 
Lachnea scutellata. 
I have already described the process of spore-formation in 
the ascus as represented in Erysiphe communis , and have given 
some figures indicating that the process in Ascobolus and 
Peziza is essentially the same as in Erysiphe 1 . The process 
is so unique in the method of cutting out the spore from 
the protoplasm of the ascus that I have continued the investi- 
gation of it in a number of other forms. Lachnea scutellata 
has proved especially favourable, from its abundance and 
the relatively large size of its nuclei, for investigating the 
phenomena in the ascus. And since, as I have already noted, 
the doctrine is widely accepted that the ascus is a more 
highly developed and specialized member of the same group 
of endogenous spore-producing cells as those I have been 
describing, it will be worth while to describe the process here 
once more as a basis for comparison, as well as to note minor 
differences from what has been already described for the asci 
of the above-mentioned forms. 
L. scutellata is a very common cup-fungus growing on 
decaying wood in moist, shady places. The whole plant is 
bright red and the disk is bordered with long, stiff septate 
and pointed bristles. The material fixed in Flemming’s 
solution is clear and transparent, neither so dense nor so 
1 Jahrbiicher fur wiss. Bot., Bd. xxx, p, 249. 
