SILURIAN BIVALVED MOLLUSCA OF VICTORIA. 
Family Pteriidse. 
Genus Actinopteria, J. Hall, 1883. 
Actinopteria texturata, Phillips sp., Plate IV., Figs. 68, 68a. 
Avicula texturata, Phillips, 1841, Palaeozoic Fossils of 
Cornwall, W. Devon and Somerset, p. 51, PI. XXIII., Figs. 
87 a, b. 
Pterincea texturata, Phill. sp., R. Etheridge, 1888, Foss. 
Brit. Islands, Vol. I., p. 159. 
Actino'pteria texturata, Phill. sp., Whidborne, 1892, 
Devonian I aun a (Pal. Soc. Mon.), p. 74, PL IX., Figs. 2, 2 a, 3, 
3 a, 5-7. 
Observations . — This is an oblique shell with an unusually 
deep left valve. The ornament is very distinct from the usual 
type in this genus, consisting of a series of rounded radial rib- 
lets crossed at varying intervals by moderately thin undulating 
laminae, and this gives to the shell-surface a woven appearance. 
The only difference between our form and already described 
specimens is the convexity of the posterior wing of the 
left valve, which, however, seems to be a minor character. 
An extraordinarily large specimen, which may belong to this 
species, occurs in the present series; this specimen shows a 
tendency in the gerontic stage to throw off irregular concentric 
laminae on the shell-surface, instead of regular, rounded 
threads, whilst the radii become almost obsolete towards the 
ventral margin. 
The previously-recorded examples of Actinopteria texturata 
were from the Devonian, of Devonshire, England; the occurrence 
of Victorian specimens thus extends its range both from a geo- 
graphical and geological point of view. 
This figured specimen is probably that referred to by Mr. 
Cresswell as “ Pterincea sub-falcata, or an allied species.”* It 
differs from Conrad’s sub-falcata in the character of the ribs, 
which in that species are not crossed by intermediate threads. ’ 
Measurements— Spec, a (figured). — 
Height, 23 mm.; length, 19 mm.; depth of valve, 5 mm. 
Spec, b ( { texturata ) — 
Height, about 53 mm.; length, about 46 mm.; depth of 
valve, about 16 mm. 
*Proc R. Soc., Viet., Vol. VI., N.S., 1894, p. 156. 
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