240 
Mautiniopsis ? STJBRADiATA, var. MoEUisii, var. nov., PL 11, figs. 12 and 13. ? 
Spirifer suh'adiatus, Morris in Strzeloolci’s Phys. Descrip. N. S. Wales, &c., 184.5, t. 1.5, f. 5 [non t 15, 
f. 5 a and d, t. 16, f. 1-4. 
Spirifera r/I,ahra, De Koninolc, Foss. Pal. Nouv.-Gallcs dn Sud, 1877, Pt. 3, t. 12, f. 1, lc«, t. 11, f. 8 [non 
t. 12, f. 16, If). 
Var. Char. Sliell round-oval, convex, width and height approximately equal, or 
hut very slightly different, hiuge-line much shorter than the width of tlie shell ; ventral 
area well developed, ventral umbo usually somewhat depressed and channelled, but not 
greatly incurved ; dorsal fold high, broad, and undivided ; sinus very broad and deep, 
continuous with the channelling of the umbo, and limited on each side by a prominent 
obtusely rounded fold ; surface quite plain with the excejdion of growth laminae. 
Ohs. I propose to distinguish by the above varietal name those forms of 
M. subradiata in which the longitudinal measurement is at least equal to the transverse, 
and at times exceeds it, giving rise to an oval outline. Such a variety is represented 
by the figure of Morris above quoted. This shape is accompanied by a very pronounced 
fold and sinus, the former being limited laterally by a depression and corresponding 
fold on each side, and the latter by bounding obtuse ridges, or folds. The true 
M. subradiata is much wider than high, as expressed by Mr. G. B. Sowerby,* who says, 
“ The breadth of this shell is rather greater than its length.” 
A very closely allied shell, so far as external appearance goes, is Spirifera 
homhronianusf D’Orb., in which the umbo is grooved, even quite to the apex of 
the beak. 
At times this variety assumes one or two other rib-like folds in addition to 
those bounding the fold and sinus. I have seen one example with three ribs on each 
flank, and three others with two. An additional one is visible in Morris’s figure. 
Loc. and Horizon. Spring Creek, Cania, Burnett (W. H. Bands) — Gympie 
Beds. 
Maetiniopsis Daewinii, Morris, sp. 
PI. 9, figs. 13 and 14 ; PI. 39, figs. 5-7. 
Spirifer Sarwinii, Morris, Strzelecki’s Pliy.s. Desorip. N. S. Wales, 184.5, p. 279 {non De Koninek). 
„ sulradiatus, Morris, loc. cit., t. 1.5, f. on (%. ooeci exclvsis — non G. B. Sowerby). 
„ Darwinii, Dana, GeMogy Wilkes’ XJ. S. Explor. Exped., 1849, Vol. x., p. 684, Atlas, t. 1, 1. 7. 
„ Darviinii, Etheridge 61., Proo. K. Phys. Soc. Edinb. 1880, v., p. 281, t. 7, ff. 7-10, t. 8, f. 11. 
Sp. Char. Transversely ovoid, very convex, gibbous and deep, with the valves 
equally convex ; hinge-line very short, much less than the width of the shell ; alar 
angles regularly rounded ; alar expansion, or lateral portions of the shell, short, 
rounded, and attenuating but little outwards ; front margin deeply sinuated. Ventral 
valve convex, depressed from above in the umbonal region, with a very deep, broad, and 
pronounced sinus, plain and without subdivisions of any . kind ; cardinal process 
depressed, not high, quite horizontal ; umbo but little incurved ; area short and broad. 
Dorsal valve very convex in the middle line, quite “pigeon-breasted,” with a high, much 
pinched up, and very straight-sided fold, horizontal in the umbonal region, projecting 
to the front sometimes far beyond the lateral front edges of the valves, and subdiinden 
in casts for about half its length by a narrow slit, indicating the presence of a thin 
septum ; area small. The dental processes, and their extensions in the ventral valv^®, 
are verv thick, almost completely surrounding the muscular impressions ; the latter 
deeply excavated, and lingual m outline, convex medianly. The septal processes e 
the dorsal valve are very thick and short ; combined muscular impres sions alm ^ 
* Darwin’s Geol. Obs. Vole. Islands, 1844, p. 159. 
+ Dumont D’Urville’s Voy. au POle Sud, Geol. Atlas, t. 6, 6f, 15-18. 
