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in thinner layers as is seen f. inst. in its smaller twigs, is darker 
or lighter brownish, often with a tinge of reddish. A variation in 
size of the spines is also often to be observed, and in some cases 
I have furthermore observed an increase of size in the spines 
when the axis expands over a somewhat flat substratum. 
A theoretical reasoning thus decidedly speaks in favour of Dar- 
win’s opinion, and a glance at the present specimens (Fig. 32 a) 
strengthens it at once. All the present specimens are not only 
covered by the horny, and spiny bark mentioned by previous authors; 
but also the soft parts of the antipatharian spread over the barn- 
acle and, moreover, generally carry well developed polyps in rather 
great numbers. This is in itself satisfactory evidence of the cor- 
rectness of Darwin’s statement, the soft parts ofan antipatharian 
not exceeding the horny skeletonal parts of the coral; the occur- 
rence of coenosark with polyps thus necessarily demands an under- 
lying layer of coral axis substance. To this may be added that 
the horny bark covering the cirriped without any demonstrable 
boarder passes into the horny axis of the antipatharian, as is seen 
in sections. 
Annandale has observed calcareous spines of the scales fit¬ 
ting into the thorns of the bark; no such spines could be traced 
in the present specimens. On the other hånd, a peculiarly regular 
arrangement of the spines is obvious: a study of the plates of the 
barnacle reveals rings of growth, more whitish zones alternating 
with darker, or rather more pellucid narrower zones; in analogy 
with other animals, we may conclude that the latter zones only 
contain little organic matter and represent a period of slow growth 
in the scale, whereas the more whitish, opaque areas contain much 
organic substance and exhibit a rapid growth. Now the spines of 
the horny bark always gather along the pellucid (inorganic) zones 
and almost entirely fail in the opaque areas, thus accentuating the 
zonar structure of the plates. 
The specimens from Japan stand near the subspecies indica 
Annandale (1909) and their external aspect exactly corresponds 
with this subspecies. As far as it is possible to discern, there 
are nevertheless differences present in the animal which cause us 
to regard them as representatives of a forma japonica nov. As 
