Mesoxylon and an Allied Genus . 
7 
Nature of the 1 Appendage ’. 
The nature of the appendage of the branch seen in several sections of 
the first series described (from 2781 onwards) remains doubtful. From the 
evidence of the sectiofi represented in Text-fig. 1 and PL III, Fig. 17, it 
would appear that the appendage is a secondary branchlet, for it is clearly 
subtended by a bract. The other four cases observed (a typical example is 
shown in PJ. I, Fig. 2) are all from detached buds or branches. In all of 
these the appendage lies outside the regular cycles of bracts, and is of 
relatively large size ; in the case figured, for example, it measures quite 
1 mm. in diameter, while all the rest of the bud is only about 1*7 x 1-3 mm. 
The appendage is not subtended by a bract in any of these examples, though 
in that figured there appear to be one or two on one side of it. The struc- 
ture of the appendage does not suggest a branchlet ; it rather resembles 
a somewhat large bract cut through its basal part ; it is flattened or 
grooved towards the axis of the branch. The slender vascular strand in the 
case figured has a square xylem-group with the smallest elements almost 
central (PI. I, Fig. 3) ; it thus appears to be mesarch, and does not differ 
essentially from the bundle of a bract. The distribution of the fibrous 
tissue is also similar in the appendage and the bracts ; in both, at a little 
distance above the base, it is chiefly concentrated on the abaxial surface, 
where it forms three or more bands, one being median. 
On the whole, therefore, the evidence, apart from the case of the section 
2781 (Text-fig. t), appears to be in favour of the appendage being itself of 
the nature of a bract. It is possible that the appearance of a branchlet sub- 
tended by a bract in the case cited may be deceptive, for here also one might 
interpret the appendage as a bract, cut very obliquely and still in connexion 
with the branch, the apparently subtending bract being merely one of 
an overlapping series. 
In the other cases, where the appendage lies to the exterior of the 
bract-cycles, one might interpret it as the prophyll of the branch, probably 
supplied by the little bundle given off from the branch-stele near its base 
(see PL III, Fig. 19 and Text-fig. 2). In any case it cannot be said that 
there is any sufficient evidence for the appendage representing the pedicel of 
a seed, as at first seemed probable. 
A natomical Details. 
A few points in the anatomical structure of the fertile shoot and 
its branches remain to be considered. 
The wood generally has been found to consist of spiral and scalariform 
elements, thus resembling the inner zone of the wood in the vegetative stem. 
Considering the thinness of the wood in the shoot and branch, this is 
not surprising. 
