270 
DOUGLAS HOUGHTON CAMPBELL 
The sporogenous region becomes more clearly defined as cell- 
division proceeds, and there is soon to be made out a distinction 
between spore mother-cells and elaters. No definite relation could 
be made out between these. The elaters occur either singly or in 
small groups irregularly distributed among the very much more 
numerous young spore mother cells (fig. 6, B). A few elaters could 
Fig. 6. A . Upper part of a young sporophyte showing the beak-like prominence 
at the apex, X 6o. B. The sporogenous tissue from an older sporophyte showing a 
young elater (el) and the young spore mother-cells, X 400. 
often be found radiating from the base of the capsule, but there was 
nothing which could be described as a definite elaterophore. The 
elaters are less numerous than is usual among liverworts, but they 
finally attain a length which probably exceeds that of any other known 
form. 
Gruni2 states that the rounding off of the spore mother-cells and 
the spaces between them which are seen in the later stages are partly 
due to the disintegration of some of the sporogenous cells; a careful 
examination of the writer's preparations of these stages, which 
were well fixed and stained, showed no evidence of the breaking 
down of any of the cells, and it seems practically certain that the 
separation of the elaters and the rounding off of the spore mother- 
12 L. c, p. 372. 
