CARBONIFEROUS FISH-FAUNA, 
Pig. 2 . — Gyracanthides murrayi . , A. S. Woodw.; pelvic fin-spine, side-view, nat. size. 
traced from the base towards the slender apex of the spine, where 
there is an indication of a worn surface. The base of insertion is 
very extensive, as usual, its length probably equalling one-half 
the total length of the spine. One fine example apparently of 
this spine, obtained by Mr. Sweet from Bed W in the Mansfield 
section, is nearly twice as large as the original of text-fig. 2. Its 
outer ornamented face is broken away on the exposed side, hut 
the tissue of the spine is sufficiently well preserved for micro- 
scopical examination. It exhibits a remarkably coarse vascular 
structure, identical with that described by Agassiz in Gyra- 
canthus. 1 
Median Fins . — The specimen represented in PI. V, fig. 1 , is 
very imperfect anteriorly, showing only a hollow mould of parts 
of the pectoral fin-spines, one displaced large free pectoral spine, 
and part of one of the pelvic fin-sjiines ; but it is important as 
displaying the caudal region of the fish, with traces of the median 
fins. This fossil seems to have been selected by McCoy ( loc . cit., 
p. 24) as the type of a species which he intended to describe 
under the name of Chiraropalus langtrei ; but the paired spines 
already mentioned prove that it really belongs to the Gyracan- 
thides now under consideration. As shown by the figure, there 
is part of a fin-spine above the dorsal border of the trunk (at c) 
opposite the insertion of the pelvic fin-spine. In another more 
fragmentary specimen (PI. Y, fig. 2) there is also a small spine, 
chiefly shown by the mould of its internal cavity ( h ) nearly 
opposite a piece of spine (a) which seems to represent the pelvic 
fin-spine. The first example might possibly be the tip of one of 
1 L. Agassiz, “ Ee<;h, Poiss. Foss.,” vol. iii. (1843), p. 214, pi. A, fig. 6. 
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