363 
acter of a rhizine though it is directed upwards, but from the lower part of the 
same cell a typical assimilative shoot is given off. 
The ramification has been carefully described by NÂGezr and Berruorn, The 
frond is usually flat, the long shoots being contained in one plane, issuing alter- 
nately to the right and to the left, and the two ranks of opposed pinnæ are given 
Fig, 299. 
Antithamnion Plumula. Shoots with tetrasporangia, from Herthas Flak. A, a normal pinna. B, pinnæ mostly un- 
branched. 95:1. 
off in the same plane. Each joint usually bears a pair of pinnæ, but the long shoots 
take the place of a pinna, and the joint which bears a long shoot usually bears no 
pinna on the opposite side, and in the following joint (or joints) the pinnæ are often 
wanting over the long shoot (Fig. 299 B). On the other hand, the joint which bears 
a long shoot often produces two unbranched pinnule issuing in a plane perpendic- 
ular to the plane of the frond (Fig. 299 B). Similar pinnulæ sometimes occur on 
other joints than those situated immediately under the branchings, thus in several 
