SILURIAN BIVALVED MOLLUSCA- OF VICTORIA. 
and Bohemia); and in the same proportion complex and adverse 
conditions probably obtained on the migratory path to North 
America. 
Further proof of the general trend of these comparative 
data as derived from other groups of the Victorian Silurian 
Mollusca is shown in the Museum collections; one notable 
example being the occurrence of a gasteropod, Euomphalus 
disjunctus, J. Hall,* in the Victorian Yeringian division of the 
Silurian, specimens of which are inseparable from the shells 
described by Hall, from the Lower Helderberg of New York 
(L. Devonian). The Pteropod, Coleolus aciculum, J. Hallt of 
the Middle Devonian (Genessee Slates) of North America, 
has a close relation in a form which may eventually prove to be 
identical, and which is not uncommon in the Melbournian shales 
of South Yarra.t 
VICTORIAN SPECIES OF 
WITH THOSE 
SILURIAN PELECYPODA, 
FOUND ELSEWHERE. 
COMPARATIVE TABLE OF 
IDENTICAL 
Genera and Species. Division, Foreign Area. Formation. 
Cardiola cornucopia, | Melbournian | Europe Silurian 
Goldfuss sp. (C. 
interrupta, Sow.) | 
Prelucina ancilla, | Yeringian... | Bohemia ... | L. Devonian 
Barrande 
Nuculites coarctatus, | Melbournian | Great Britain Sil. (Ludlow) 
Phill. sp. : 
Nucula lamellata, J. * North America Mid. and Up. De- 
Hall vonian 
Pterinea lineata, | Yeringian... |f Great Britain ... | Silurian (Ludlow) 
Goldfuss || Germany lL. Devonian 
? Plerinea tenuis- | Melbournian | Great Britain Sil. (Wenlock to 
triata, McCoy 
?Ambonychia — acuti- 
costata, McCoy 
Actinopteria lextu- 
rata, Phiil; sp. 
A. hoydi, Conrad sp. 
Modtolopsis 
nata, Sow. sp. 
Cypricardinia 
texta, Barr. 
con- 
compla- 
Yeringian ... 
Melbournian 
Yeringian ... 
Wales 
shire) 
f England 
|| North America 
Great Brjtain 
|( Great Britain ... 
| Bohemia 
; 
| England (Devon- 
Up. Ludlow) 
Sil. (Wenlock and 
L. Ludlow) 
Mid. Devonian 
Sil. (Up. Ludlow) 
M. Devonian 
Sil. (Wenlock 
passage beds) 
Sil. (Wenlock and 
L. Ludlow) 
to 
: | L. Devonian 
* Pal. New York, Vol. III., 1859, p. 340, Pl. LXV.. Fig. 8; Pl. LXVIII., Fig. 4a, 4. 
+ Pal. New York, Vol. V., Pt. IT., 1879, p. 187; Pl. XXXIIa., Figs. 11-15. 
+ Proc. RK: Sdc. “Vichis Vol. AVE, Pt Try 
[9] 
N.S., 1994, p- 3393 Pl. XXXL, Fig. 7. 
