SILURIAN BIVALYED MOLLUSCA OF VICTORIA. 
From the Tentaculite slates (GU of Bohemia, Barrande has 
described Lunulicardium granulosum, which, although a more 
depressed shell, is closely related to our species, more especially 
in the granulose ornament of the shell surface.* * * § 
In the shaly mudstone from the mouth of Starvation Creek 
there also occur numerous small bivalves (Figs. 64, 65), which, 
on first examination, might reasonably be mistaken for a species 
of Vlasta; in its superficial character and general form, however, 
it corresponds very closely to the prodissoconch and early disso- 
conch stages iof Lunulicardium antistriatum. In connexion 
with these specimens it is interesting to compare the figure of 
f Vlasta , sp., figured by Mr. F. R. C. Reed from the Upper 
Silurian beds of Zebingyi, Burma.! 
Horizon and Locality . — Silurian (Yeringian). Common in 
the blue slates and shales of McMahon’s Creek, Upper Yarra, 
Dept, of Mines coll. (3778); Reefton, near Warburton, Dept, of 
Mines coll. (3432, 3434)4 
The apparently young examples, or micromorphs of the pre- 
sent species occur at Mount Matlock, associated with Tentacu- 
lites matlockiensis, Cbapm., specimens presented to the Museum 
by N. Lepoidivil, Esq., in 1877; and from the mouth of Starva- 
tion Creek, coll. Dept. Mines, Viet. (3368). § [2257 (type), 2255, 
2260-61.] 
Family Ambonyehiidse. 
Genus Ambonychia, J. Hall, 1847. 
Arnbony cliia acuticostata, McCoy, PI. IV., Fig. 66. 
f Ambonychia acuticostata, McCoy, 1852, Brit. Pal. Foss., 
p. 264, PI. IK., Figs. 16, 16a. 
Observations . — This is a sub-trigonal or sub-ovate shell, 
which in its general form and ornamentation closely resembles 
McCoy’s species from the Wenlock and Lower Ludlow Beds of 
Wales. Our specimen shows a less distinct costation on the 
umbonal part of the shell, but this may be due to imperfect 
*Syst. Sil. Bohem., Vol. VI., Pt. I., PL 192, Figs. 6-10. 
+ Palaeontologia Indica, N.S., Vol. II., Mem. 3, 1906, p. 119, PI. VI., f. 37. 
+ See Prog. Rep. No. IV., 1877, Geol. Surv. Viet., pp. 156, 157, where the late Sir F. 
McCoy indicated their age to be Upper Silurian (Ludlow). 
§ See tom. supra cit., p. 156, where McCoy refers to these specimens as “a small 
Aviculoid shell allied to Ambonychia (new species).” 
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