20 
The sliells now before ns are casts of small right and left orbicular 
valves, botli moderately convex. The anterior auricle of the right valve is 
elongately triangular, its outer margin rounded, longitudinally delicately 
eostate, and cut off by a long, linear, obli(][iic byssal sinus ; the posterior 
auricle is small, rectangular, and ill-delined. The left valve is similar to the 
right, botli auricles are rectangular, and apparently equal in size. There is no 
scul])ture preserved except a few oblicpie strim along the auterior margin of 
one specimen. On the anterior auricle of another tliere are traces of transverse 
growth ridges, giving rise to a reticulate sculpture. 
In De Koninck’s illustration the anterior auricle is narrower than in 
the corresponding part of any of ours, with a straight loAver edge, more nearly 
resembling that shown in the ligure of A. Laurienti. 
McCoy says that in his Tccten plyclioiis the left anterior auricle is 
“ square at its extremity,” and the latter longitudinally plicate. M^e regard 
liis ligure as representing the young condition and a right valve, and those 
now under description as the adult state. Although not from the same 
locality as the latter, P. ptijcliolis was obtained from about the same horizon 
in the Carboniferous. 
Localities and Horizon. — Near Crow’s Nest, Mt. Victoria, Mount 
Morgan, Queensland {J. Smith) ; near Gresford, N. S. AValcs (C. Cullen ). — 
Carboniferous. 
Collection. — Mining and Geological Museum. 
Aviculopecten, sp. 
(Plate XV, Fig. 10.) 
Amculopccten granosus, l>e Koninck (non 8by.), Koch. Pal. Foss. Nouv.-Galles du 8ud., 
Pt. .S, 1877, p. 158, t. 22, f. 10. 
Observations. — An imperfect valve Avas figured liy Dc Koninck, bclicAX'd 
l)y him to l)c referable to Lecten granosus, J. de C. Sby.,^ Avithout cither auricles 
and Avith imperfect margins. AVe have an equally imperfect specimen before 
us, but similar to De Koninck’s ligure. In this instance there is no doubt that 
his description is not that of the fossil figured, but of the more perfect European 
sliell, and it is extremely difficult to decide Avhctlier or no the former is the 
' J. cle C. Sowerby— Min. Con., 1827, VI, p. 141, t. 574, f. 2. 
