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.

 
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Bibliographic Data

Short Form
Dun, 1932, Rec. Aust. Mus. 18(8): 411–414
Author
W. S. Dun
Year
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
/Uploads/Journals/17219/745.enw
Title Page
/Uploads/Journals/17219/745.pdf
File size: 91kB
Complete Work
/Uploads/Journals/17219/745_complete.pdf
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