128 PROCEEDINGS OF THE ROYAL SOCIETY OF QUEENSLAND, 
DESCRIPTION OF THE SPECIES.—The specimens examined 
form a related series characterised by (1) very slight 
inequality of the valves, (2) large size, (3) prominent 
pallial line and small sub-cireular muscle sears, and (4) 
amazingly thin, relatively smooth shells. The type 
specimen of /. maximus measures 30 ems. along its greatest 
axis, yet its shell was only 1-5 mm. thick. A specimen of 
I. scutulatus attains a height of 10 ems. with a shell of 
0-5 mm. thickness. Muscle sears are a feature extremely 
rarely seen in this genus, so that the presence of a prominent 
scar and pallial line on every specimen in this collection is 
of great interest. 
INOCERAMUS MAXIMUS Lumbholz. 
(PI. VIL. figs..1, 2a, and 2b.) 
1885. Inoceramus sp. B. Lundgren, Bihang. till. K. Sven. Vet.-akad. 
Handl., B. I1., pp. 3-6, pl. I. 
1889. I. maximus. C. Lumholz, ‘‘ Among Cannibals’’ (London), p. 
367, with text-fig. 
Sp. Chars—Shell attaining a large size, the outline 
being that of an oblique oval with a slightly curved axis. 
Somewhat inequivalve; very inequilateral, the umbones 
being terminal and the antero-dorsal area very sharpiy 
truncated. Postero-ventral angle regularly rounded. 
Height approximately equal to length; hinge line about one- 
third of the total length. Umbones acute, the left shghtly 
more prominent than the right. Axis of growth gradually 
curving concave to the hinge line. Pallial area very 
marked, roughly parallel to the outline and occupying about 
one-third of the internal surface. Shell substance extremely 
thin. Ornamentation consists of concentric ribs, which are 
not very marked on the superior part of the shell and almost 
disappear on the ventral portion. 
Obs.—The type specimen is a huge shell with the valves 
in apposition. Its dimensions are: Length 24 ems.; height 
23 ems.; width (two valves together) 8-5 cms.; hinge-line 
about 7 cms.; thickness of shell substance 1-5 mm. 
This specimen was originally described and figured by 
Lundgren in 1885.2, Unfortunately in doing so he mistook 
* Lundgren, Bihang, til). K. Sven. Vet-akad. Handl., B. IL., pp. 
3-6, pl: I: 
