178 THE JOURNAL OF BOTANY 
I find the central strand quite unrepresented by any special cells, 
and only defined, or apparently defined, by the cells of the ground 
tissue narrowed and converging to a point in the centre of the 
stem. This would seem to agree precisely with the meaning 
intended to be conveyed by the somewhat ambiguous term “ obso- 
lete,” as applied to B. densum. 
As regards the cortical cells, the term ‘‘ thin-walled” is ob- 
. No doubt there is no tissue in the 
explains the apparent discrepancy. 
2. The curious “ brood-filaments” which appear on the back of 
the leaves of B. densum, and are rightly given by Limpricht an im- 
portant place in the diagnosis of the species, are not mentioned in 
any description of A. compactum so far as I am aware. ey are, 
__8. Inflorescence. This undoubtedly presents the most serious 
difficulty in the case. I believe, however, it is sufficiently accounted 
may be taken for granted that the male flowers are small and 
inconspicuous, even when present. Now Kindberg, in his descrip- 
