Australian Museum Journal The lower marine forms of Myonia, with notes on a proposed new genus, Pachymyonia

Shortform:
Dun, 1932, Rec. Aust. Mus. 18(8): 411–414
Author(s):
Dun, W. S.
Year published:
1932
Title:
The lower marine forms of Myonia, with notes on a proposed new genus, Pachymyonia
Serial title:
Records of the Australian Museum
Volume:
18
Issue:
8
Start page:
411
End page:
414
DOI:
10.3853/j.0067-1975.18.1932.745
Language:
English
Plates:
plates li–lii
Date published:
13 September 1932
Cover date:
13 September 1932
ISSN:
0067-1975
CODEN:
RAUMAJ
Publisher:
The Australian Museum
Place published:
Sydney, Australia
Digitized:
05 February 2009
Available online:
06 March 2009
Reference number:
745
EndNote package:
EndNote file
Title page:
Title page (91kb PDF)
Complete work:
Complete work (957kb PDF)

Abstract

As will be seen by reference to the figures on Plates li and lii, the Myonia of the Lower Marine of New South Wales differs markedly from the species so common in the Upper Marine. The former as a whole are characterized by smaller size and a tendency to develop thicker valves as compared with the Upper Marine types. This was due probably to the fact that the larger thin-valved types described in the first part lived in shallower and smoother waters, in some cases probably sub-estuarine. The same remarks apply equally to the members of the Chaenomya group occurring in the Upper and Lower Marines. The affinities of Myonia have been discussed by Mr. H. O. Fletcher.

It has been considered advisable to make a new genus, Pachymyonia, for Etheridge's Maeonia morrisii.