185 
of tlie ventral furrow there are thirteen or fourteen radiating, simple, rounded 
folds, separated hy narrow, indistinct furrows. The beak is relatively small 
and strongly recurved, leaving only a short distance between it and the beak 
of the dorsal valve. The hinge area occupies the whole breadth of the shell, 
but is not much elevated. The dorsal valve is a little deeper than the ventral 
valve, and is slightly depressed near the ears, the lateral margins of which 
form a right angle with the hinge-line. Its dorsal ridge is broad, prominent, 
and simple, and has no traces of rudimentary folds. The lateral folds are like 
those of the ventral valve, to which they correspond. The surface is crossed 
by undulating concentric rings of growth. 
Dimensions. — The length is thirty-five millimetres, the breadth sixty, 
and the thickness twenty-five. 
Relations and Differences, — By its external ornamentation this 
Spirifer strongly resembles S. plenns, J, Hall, (’^) l)ut it cannot l)e confounded 
with that, because S, plenus is nearly as long as broad, proportionately much 
thicker, and so much more convex as to be gibbous. 
Horizon and Localities. — This lovely species, which I have great 
pleasure in naming after the indefatigable pioneer of New South Wales, was 
found by hiui in a greyish sandstone at Wollongong, and in a black limestone 
at J ervis Bay, where it seems rare, as he found only one specimen of it at 
each of these places. 
Spirifer pinguis, 
Spii'ifefa rotundata, 
Spirifer rotimdatus, 
53 33 
Spirifera rotundata, 
„ pinguis, 
Terehratula pinguis, 
Spieifer ping-uis, j. So'werhyi^ 
PL XIV, Fig. 2. 
J. Sowerby, 1820, Min. Concli., Ill, p. 125, pi. 271. 
J. cle Carle Sowerby, 1824, Miu.- Conch., V, p. 80, pi. 461, fig. 1 
(non W. Martin). 
Defiance, 1827, Diet, Sci. Nat., L, p. 295. 
Davreux, 1831, Const. Geogr. Province cle Liege, p. 272, pi. 7, fig. 8. 
J. Phillips, 1836, Geol. Yorkshire, II, p. 218, pi. 9, fig. 17. 
Idem, 1836, ibid., p. 218, pi. 9, fig. 18, 19. 
Deshayes, 1836, In Lamarck, Aniin. sans Vert., VII, p. 374. 
(0 Rept. Geol. Survey Iowa, p. 603, PL 13. fig. 4. 
l&pirifera 2 nnguis, E. Etheridge, Junr., Geol. and Pal. Q’land, 1892, p. 233. — W.S.D.] 
