ON THE DEVELOPMENT OF LICHENOPORA VERRUCARIA. 107 
in consequence of the degeneration of the polypides or from 
other causes. 
Stage B.—Formation of the Follicle, &c. 
Although the embryo and its investments can be recognised 
with certainty at this stage, it is by no means easy to make out 
all the details. 
Fig. 19 shows a part of the polypide, with the embryo, of a 
colony which possessed functional polypides in 2}, z’, and 2’, 
and had two other zoccia which had reached the stage at which 
the polypide-bud becomes obvious. The fertile zocecium is 
either z? or z>; it possesses a brown body and a small testis, 
neither of which is shown in the section figured. The body- 
cavity contains some ripe spermatozoa, some of which are seen 
in the immediate neighbourhood of the embryo. The latter 
consists of several nuclei embedded in a mass of protoplasm 
which lies in a definite cavity. This is bounded by a layer of 
cells which may be termed the follicle. 
Fig. 22 is from z* in an older colony which had four old and 
one half-grown polypide, and two buds. No brown bodies 
could be distinguished in this case—a very unusual phenome- 
non in colonies of this age, although quite common in older 
colonies. The four mature polypides are, however, conspicu- 
ously old, and their alimentary canals have solid contents which 
are probably the missing brown bodies. This question will be 
considered later. The investments of the embryo are rather 
more definite than in fig. 19, and it is more difficult to make 
out with certainty the limit between the follicle and the em- 
bryo. At least five of the central group of nuclei clearly belong 
to the latter. 
Fig. 21 shows a transverse section of the follicle and embryo 
at a stage between the last two figures. The colony measured 
‘40 by ‘21 mm., and possessed three polypides only, of which 
either z? or z> was fertile. The follicle is somewhat thicker 
than in the cases previously considered, and possesses more 
than one layer of nuclei. A brown body is present, as usual, 
in the fertile zocecium. 
