SILURIAN BIVALVED MOLLUSCA OF VICTORIA. 
Cypricardinia nitidula, var. contexta, Barrande, 1881, 
Syst. Sil. Boheme, Vol. VI., Pt. I., PI. 257, Fig. IV., 19-24. 
Observations. — Barrande’s Cypricardinia nitidula is pro- 
bably the same form as C. planulata, and it therefore falls into 
the synonymy of the latter species. The variety contexta of the 
same author, however, is undoubtedly similar to some of the 
British fossils described by Salter under Conrad’s name of C . 
planulata , but from which they differ in having a secondary 
interlame] lar ornament. The Victorian specimens show the 
striae to be often arranged in chevron fashion, and a tendency 
in this direction is indicated in one of Salter’s figures (Fig. 
4, loc. cit.), shown by the peculiar twist of the radii. The 
Bohemian, British and Victorian fossils, having a similar 
ornamentation, may perhaps be more conveniently referred to as 
C ypricardmia contexta, Barrande. The British examples of C. 
contexta were described by Salter as being pretty generally dis- 
tributed through the Wenlock and L. Ludlow series, where it 
appears to be associated, as in Bohemia, with C. planulata. 
The Bohemian examples are recorded from Stage Ff 2 , which 
by Kayser and others is now considered to be Lower Devonian, 
although formerly placed in the Silurian. 
Another striated form of the same type of shell as the above 
is to be found in Sandberger’s C. crenistria* represented by the 
more highly convex right valve. In this species, however the 
striae are essentially regular and radial. 
. Horizon and Locality. — Silurian (Yeringian). From the 
parish of Yering, coll. Geol. Surv. Viet., 1862; north of Lily- 
' i ll P rcse Med by the Rev. A. \V . Cresswell, M.A. ; from a 
994.191 WC?11 near Cr ° ydon ’ P resented b y Mr. Thos. Warr. [7946, 
Family Lueinidae. 
Genus Paracyclas, J. Hall, 1843. 
Paracyclas siluricus, sp. nov. PI. VI., Fio- s . 85 85a 
Description.^ Shell orbicular, length equal to the height- 
more or less strongly convex, compressed in the cardinal region 
Beaks central, prominent, roundly acuminate. Anterior border 
not so widely rounded as the posterior, an d less compressed 
xxvni, lr g T ,h ' in “ chen 
