io 6 
ALASKA GEOLOGY 
Ostrea sp. 
Localities .— Upper beds, 3373 ; lower beds, 3377. 
A large species in imperfect condition blit resembling closely O. 
idriaensis Gabb, from the Tejon Eocene of California. Specimens 
reach a length of 80, and a breadth of 55 mm., and are frequently 
perforated by the Cliona alaskana. 
Pecten (Chlamys) sp. 
Locality . — Upper beds, 3373. 
Fragments of the upper valve of a Pecten of the type of P. is - 
landicus Muller having nineteen ribs on the disk and six on the poste¬ 
rior auricle, with traces of a fine reticulate surface sculpture, were 
obtained by Dr. Palache. The height of the valve would be about 
40 mm. and the proportions about those of P. islandicus . 
Modiolus harrimani sp. nov. 
pi. ix, fig. 7. 
Localities . — Upper beds, 3373 ; lower beds, 3378, very abundant 
but crushed. 
Shell small, short, broad, with nearly terminal beaks ; anterior end 
narrow, rounded, blunt; posterior end broad, compressed, subtrun¬ 
cate ; base nearly straight, with the valve above it and below the 
median convexity somewhat impressed. Length 19, maximum width 
12.5, diameter about 6 mm. 
This curiously wedge-shaped little Modiolus is concentrically stri¬ 
ated. It is very abundant but always distorted in the lower beds ; a 
single valve in normal condition was found in the upper beds. 
Modiolus sp. 
Locality . — Lower beds, 3377. 
A fragment of a large rounded quadrate species recalling the recent 
M. vulgaris was collected. It is rather strongly concentrically sculp¬ 
tured. 
Modiolus alaskanus sp. nov. 
pi. x, fig. 3. 
Locality. — Upper beds, 3373. 
Shell small, rounded quadrate, finely concentrically striated, moder¬ 
ately convex; anterior end with the beaks adjacent, rounded; base 
nearly straight; posterior end wider, rounded, obliquely subtruncate ; 
ventral third with the usual constriction. Length 17, maximum width 
9, diameter about 4 mm. 
