MANSFIELD DISTRICT, VICTORIA. 
pedicle somewhat exceeding one-third of the length between the 
anal fin-spine and the lower lobe of the caudal fin. Scales very 
small, equilateral, fiat and smooth. 
Description of Specimens . — The type-specimen, of which the 
greater part is shown in PL VII, fig. 1 , is associated with the 
imperfect trunk of a similar fish on a small block of sandstone 
which has unfortunately been weathered. The extreme slender- 
ness of the trunk and the elongation of the upper caudal 
lobe are indicated ; but the only remains of fins are fragments 
of the dorsal, anal and caudal. The dorsal fin-spine, 
just in front of a crack in the fossil, is clearly much smaller, 
more curved, and more remote than the anal fin-spine, 
which is incomplete distally. Both these spines are broken, and 
the anal spine (enlarged in fig. 1 b) displays its extensive internal 
cavity. The caudal fin (enlarged in fig. la) seems to he nearly 
complete in the upper lobe, but lacks the greater part of the 
lower lobe. A larger specimen of the tail (PI. V, fig. 3) is 
similarly imperfect. The very small scales are nearly or quite 
square, and most of them are exposed from the inner face, which 
exhibits its usual convexity (PI. VII, figs. 1 c, Id). In one part 
of the fossil their outer face is distinctly shown to he flat and 
smooth (PI. VII, fig. le). On the membranous expansion of 
the caudal fin they become minute (PI. V, fig. 3a). In the 
original of PI. Y, fig. 3, the lateral line can be traced to the 
basal portion of the upper caudal lobe, and is only marked by a 
ridge-like displacement, not by an enlargement of the scales. 
Genus Eupleukogmus, McCoy. 
[Ann. Rep. Sec. Mines, Victoria, 1889 (1890), p. 21.] 
An indefinable large Acanthodian with smooth scales, of 
which two series are deepened and meet chevron-wise along the 
course of the lateral line. 
The peculiar enlargement of the scales of the lateral line 
characterising this genus, has only been observed hitherto in 
certain primitive species of Diplacanthidse from the Lower Old 
Red Sandstone of Scotland, described under the generic name of 
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