4 
instance, that some are very imperfect, otliers arc in tlie condition of more or 
less distorted casts and impressions, and in the ^reat majority of cases only 
one valve is ligured. 
It Avill he readily admitted that tliis condition is more than unsatisfactory 
and not conducive to accurate determination, and as a tentative solution we 
propose puhlishing’ a scries of photogra 2 )liic reproductions of specimens 
illustrating onr interpretation of the dilfercnt species. 
These figures arc accompanied hy a brief synonymy, diagnosis, a few 
general remarks on the figures published hy other authors, and the affinities 
of the forms in question. 
A similar treatment wdll he from time to time given to the other 
Pclecypoda occurring in these beds. 
Localities of species given refer only to specimens which have passed 
through our hands. 
, 'The following list comprises the whole of the New South Wales 
Permo-Carhoniferous Pahuopecteus, either named or described ; those in 
italics are synonyms : — 
Pccten limaeformis, Morris. 
,, illawarrensis, ,, 
,, Pittoni, „ 
,, squamuliferus, ,, 
,, suhqninquelineatns, McCoy. 
,, comftus, Dana. 
,, Icniuscnlns, Dana. 
,, mitis, 
,, tennicollis, ,, 
,, lineatus, Plews. 
Aviculopecten profundus, De Koninch. 
,, elongatus, De Koninck. 
The following name is rejected : — 
1. Pecten mitis, Dana,^ a fragment; at present unri'cognisalilc. 
’ Uana — Wilkes U. S. Explor. E.xpe(l., 1849, X (<leol.), p. 70.5, t. 9, f. S. 
