MANSFIELD DISTRICT, VICTORIA. 
Strepsodus decipiens, sp. nov. Plate VII., figs. 2, 3; Plate 
VIII, figs. 1-11. 
Type.— Scales (PI. VIII, fig. 10). 
Specific characters . — Scales with the radiating ridges and 
furrows on the exposed portion more numerous than in the 
European Carboniferous species ; the small pits and tubercles on 
the attached face also apparently more numerous than in the 
latter. Teeth [from same horizon as scales and presumably of 
same species] rather large, stout, and nearly or quite smooth, 
with the apex a little incurved but not sigmoidally bent. 
Scales . — The scales exhibit the usual variations in form, 
according to their original position on the trunk of the fish, and 
are all more or less round or oval, with a slight truncation at the 
anterior border. Most of them are preserved in a partially 
decayed condition, and they then exhibit their internal structure, 
as represented in PI. VIII, figs. 5, 6, 6a, 7, 10, 11. The 
exposed sector, seen in the lower half of these figures, is not very 
wide. Its tissue is coarser than that of the rest of the scale, 
consisting of stout radiating rods, which are closely apposed and 
crossed by a few feeble strands concentric with the border. The 
other part of the scale consists of very numerous radiating and 
concentric strands of tissue of about equal fineness. The differ- 
ence between the two structures is well shown in the magnified 
drawing, fig. 6a, where a portion of the covered area is seen to 
the left, a larger portion of the exposed sector to the right. The 
outer face of the scale is rarely observable, even as an impression 
on the rock ; but an imperfect scale associated with the original 
of fig. 10 (the type specimen) seems to show that each radiating 
rod of the exposed sector was surmounted by a delicate super- 
ficial ridge, the total number of ornamental radiating ridges being 
thus considerably more than in any scale of Strepsodus hitherto 
described. When a complete view of an impression of the inner 
face is obtained (as in the group represented in fig. 9), there is 
clear evidence of the large, antero- posteriorly elongated tubercle 
so characteristic of the middle of the scale in this and some allied 
genera. Occasionally, as in the piece of undisturbed squamation 
[ 17 ] 
