9 
Aviculopecten profundus, De Koninck. 
(Plate XI, Pigs. I and 5.) 
Aviculopecten profundus, J)e Koninck, Recli. Foss. Pal. Nouv.-aalles du .Sud, Pt. 3, 1877, 
p. 161, t. 22, f. .3. 
Observations . — Under this name i)o Koninck ligured a poor cast from 
tlu' Lower Marine Series at Harper’s Ifill — a large, snlioval, and fairly convex 
right valve, with a large wing-like posterior auricle, apparently without radii. 
NotAvithstanding that large collections have been made from the 
locality in question, we have never met with this shell in these gatherings. 
Prom other localities, on the other hand, both Upper and Lower ]\rarine, we 
have before us a few specimens that may he this species, hut we are convinced, 
from the imperfect condition of the type, that any determination under this 
name Avill ahvays he more or less open to douht. 
The specimens we tentatively refer to A. profundus, are large, suhoval, 
convex valves, and when devoid of auricles hy no means unlike our A. Mitchelli. 
The valves Avere equally convex, the posterior auricles in both valves very 
large, flattened, rounded on the outer margins, and extended as far as, if not 
further, than the posterior edges of the valves, Avith Avide hut not deep 
•emarginations helow the posterior slo|)es ; the posterior auricle of the right A'alve 
was out of all proportion to that of the anterior. The anterior auricle of the 
right Amlve (that of the left is unknoAvn) is small and rectangular, and there 
is no apparent hyssal sinus. The surface of the right valve hears from forty 
to fifty costie, Avhich appear to lie irregularly developed, in that they are 
sometimes all primary, at others divisible into primary and secondary. Loth 
auricles in the right valve are numerously radiate. The Avhole of the costie 
and intercostal spaces, inclusive of those of the auricles, are crossed hy regular, 
close, concentric, non-fluctuating, and very numerous lines, producing a 
cancellated surface. 
If our conception of l)c Koninck’s species he tlie correct one, it 
certainly differs from all other Australian Palmopectens, not eA^en excepting 
A. squamuliferus, Morris, Avhich it otherwise resemhle to some extent in the 
sculpture. 
IVe have not observed any trace of a cliondrophore, and therefore 
retain this species in Aviculopecten. 
