457 
Maccotella eeflecta, 3Ioore, sp. 
PL 20, figs, 1, 3, 5, 7, and 10. 
Avicula rcflccta, Moore, Quart. .Tourn. Geol. Soc., 1870, xxvi., p. 240, t. 12, f. 1. 
,, Barklyi, var. reflccta, Ten. Woods, Proc. Linn. Soc. N. S. Wales, 1883, viii., Pt. 2, !>. 240, t. 12, 
. 4-0. 
Sp. Char. Sliell large, transversely oval ; valves to some extent compressed, 
especially on the posterior side, very inequi valve, inequilateral, plano-convex, or concavo- 
convex. Right valve either flat, a little concave, or slightly convex in the nmbonal 
region, becoming concave and then fiat towards the ventral margin ; anterior dorsal 
margin moderately obliquely inclined ; posterior dorsal margin straight ; area inwardly 
bevelled, wide, with a thickened inflection, strong cartilage furrows, and a narrow, deep, 
and inwardly curved byssal sinus ; umbo small and nucleus-like, posterior wing large 
and flattened, margin roundly truncated. Loft valve convex, but not strongly so, the 
greatest convexity being i7a the nmbonal region, thence rapidly decreasing to the ventral, 
margin; umbo elevated, but not highly so, or gibbous; anterior folds of the area not 
particularly coarse ; posterior wing not sharply marked-off from the body of the shell 
flattened. Surface of the right valve bearing a very large number of radiating ribs or 
costas of nearly equal size, covering the whole valve. Left valve similarly ornamented, 
but the costso stronger, present on the posterior wing, and every fourth rib larger than 
the others. Concentric latnin® of both valves widely separated ; points of intersection 
of the lamin® and costso elevated into projecting frills. Muscular impressions as in the 
type species. 
05s. The shells that I have considered referable to Moore’s Avicula vqflecta are 
of much larger size than the preceding, Maccoyella BarMyi, and in comparison it must 
be borne in mind that Moore’s figure was reduced one-half. In addition, the whole shell 
18 much less convex, the right valve flat, or, what is more usually the case, convex in the 
nmbonal region, becoming concave forwards. The surface costaj are much more numerous, 
and in the right valve smaller, giving to that valve a far more finely striated appearance 
than the corresponding half of M. Barhlyi. There is little short of forty or fifty costae on 
the left valve of 31. rejlecta, and in extreme specimens perhaps even more, but, as in the 
case of the former species, the number of secondary cost® between the primary varies to 
some extent. The principal costss do not appear to project at the points of intersection 
of the concentric laminse, as semi-tubular spines, so far as I have been able to ascertain. 
The convexity of the left valve in this species is fairly marked in the dorsal portion 
of the valve ; yet, at a point about midway between the dorsal and ventral margins, 
the diameter of the valves, when in apposition, as ascertained from two fractured 
examples, is only seven-eighths of an inch. 
The inflection of the area of the right valve is very marked in this species, the 
mturned portion forming a kind of plug, filling the excavated portion of the left area 
immediately under the umbo of that valve. 
The muscular impressions appear similar to those of 31. Barhlyi, but are not as 
deeply excavated. 
The geographical distribution is equally wide with that of 3£. Barhlyi. 
Irresqicctivc of the Queensland localities, Mr. H. T. L. Brown has obtained it at 
Primrose Springs, north of Lake Eyre ; specimens are in the Mining and Geological 
^lu'seum from Milparinka, and Dunlop Station, Darling River. 
Loe. and Horizon. Wollumbilla {The late Iteo. W. B. Clarhe) ; Bungeworgorai 
Creek , near Mount Abundance ( O. Sweet — Colin. Sweet, Melbourne) ; Lake Eyre Basin 
(-ff- B. L. Brown, and Prof. B. Tate). Occurs also in the Maryborough Beds — 
T*esert Sandstone. 
