NEOZOIC INVERTEBRATES 
Ir 5 
Sasidomus popofianus sp. nov. 
pi. x, fig. 4. 
Shell rather evenly ovate, inequilateral, with low beaks nearer the 
anterior end; dorsal slopes slightly descending, the beaks near the 
anterior third of the shell; ends evenly rounded, base moderately 
arcuate ; internal margins smooth ; muscular scars deeply impressed; 
pallial line rather distant from the ventral edges of the valves, with a 
small, short, ascending subangular sinus free from the pallial line 
below; external surface rather rudely and irregularly concentrically 
sculptured. Length of internal cast 50, height 37, diameter 38.5 mm. 
Locality . — Popof Island, 3372. 
This is one of the most abundant species of the Miocene beds of 
Popof Island. 
? Callocardia (Pitaria) kincaidii sp. nov. 
pi. x, fig. 1. 
Shell elongate-ovate, plump, inequilateral, with large and promi¬ 
nent beaks three-tenths of the length behind the anterior end; anterior 
dorsal slope short, excavated; posterior slope longer and nearly 
straight; pointed rounded at both ends, base arcuate; pallial line 
with a short, wide, rounded, ascending, free sinus; exterior concen¬ 
trically striated. Length 50, height 35, diameter 21 mm. 
Locality. — Popof Island, 3372. 
This species is referred to the above group on account of its gen¬ 
eral aspect, as the hinge is inaccessible. It is quite common in the 
beds referred to. It is named in honor of Mr. Trevor Kincaid, of 
Seattle, who collected it with other fossils from Popof Island. 
Dosinia? alaskana sp. nov. 
pi* x, fig. 7. 
Shell suborbicular, rather convex, with very high prominent beaks 
nearer the anterior end; anterior slope short, deeply excavated; pos¬ 
terior slope convexly arcuate ; base arcuate ; pallial sinus short, angu¬ 
lar, free from the pallial line below; internal margins simple. Length 
55, height 53, diameter 22 mm. 
Locality . — Popof Island, 3372. 
This species has the hinge obscured, but is probably a Dosinia . 
The surface is concentrically sharply striated. 
