Tertiary.) PALZONTOLOGY OF VICTORIA. [ Mollusca. 
Priate LVIII. 
HINNITES CORIOENSIS (McCoy). 
[Genus HINNITES (pr Franc.) (Sub-kingd. Mollusca, Class Lamellibranchiata, Order 
Pleuroconcha. Fam. Pectinide.) 
Gen. Char.—Shell irregular, inequivalve, moderately oblique and inequilateral ; in the young 
state regular, pectiniform, nearly equilateral, ovate, both valves regularly ridged radiatingly, 
with small pointed beaks, and a straight hinge-line extended into quadrate ears, the anterior ear 
of the right valve with a small sinus for the passage of a byssus ; with age the growth suddenly 
becomes irregular, undulated, distorted, and fixed by the substance of the right valve, which 
develops irregular prominent concentric scaly projecting growths; left or upper valve usually 
flatter, and radiatingly ridged without squame or marks of attachment; no hinge-teeth ; 
cartilage-pit triangular, agreeing with Pecten. } 
Descriprion.— Young stage from 4 to 13 inch in leng'th, regular, ovate, very 
slightly oblique, with nearly equal subquadrate ears, valves nearly equally and 
moderately convex; surface closely radiated with narrow subangular ridges, nearly 
equal near the beaks, but each pair receiving between them irregularly from one to 
five smaller ridges towards the margin (in some specimens the original ridges 
remain so much more prominent than the intercalated ones that angular bundles are 
formed); each ridge is roughened by hollow semiconical spines formed of projecting 
angularly arched scales a little further apart than the thickness of the ridge, 
interspaces varying from the width of the ridge to four or five times the width ot 
the ridges, and closely covered with a perfectly regular pattern of oblique inter- 
secting lines of equal rounded granules, less than their diameter apart, about twelve 
in two lines; usually about eight ridges in two lines at an inch from beak, but 
varying from three to ten. Adulé growth beyond the young regular stage—valves 
suddenly becoming irregular in growth, often obliquely extended posteriorly, the 
upper or left valve irregularly undulated and flatter than the right valve, but varying 
from concave to convex; the ridges nearly equal, very irregularly undulating, the 
spinose scales less regular, and becoming obsolete at margin of old specimens; flat 
intervening spaces about twice the width of the ridges, crossed by concentric lines 
of growth; right valve with a scar of attachment, and with large irregular projecting 
concentric scaly fringes. The muscular impression large. Length of large specimen, 
34 inches; depth from beak to opposite margin about the same; width varying 
from 1 to 2 inches. 
This extremely common fossil in our Miocene Tertiary strata is 
a representative of the European Hinnites Cortesit (de Franc.) of 
the Coralline Crag of England and corresponding Tertiary strata 
on the European continent. The characters of the extinct genus 
Hinnites are well seen in this species, appearing to connect the 
genera Pecten and Ostrea. The young regular Pecten-like stage of 
growth being seen for about an inch from the beaks corresponding 
with the time it was attached by a byssus; the older stage of 
growth, when it became fixed by the shelly substance of the lower 
[ 31 J 
