196 TRANSACTIONS OF THE [May 18, 
LEPIDITTA AURICULATA (Plate XV., figs. 3a and 3b). 
Lepiditta auriculata, Trans. Roy. Soc. Can., vol. xi., pt. iv., 
p. 99, figs. 2 a and b. 
Only a mould of the left valve is known. This is purse-shaped 
and has a short ear at each end of the hinge line. There is no 
marginal rim. Two grooves in the mould at the hinge line show 
that the hinge had two oblique plates towards the posterior 
end. 
The surface of the mould is highest a short distance below the 
hinge, whence it descends gradually to the posterior margin, 
where the valve is nearly flat. This mould also shows faint, 
parallel ridges, concentric to what is supposed to be the anterior 
end. Faint lines mark off three quadrate spaces, near the hinge, 
parallel to the long plate, and corresponding in position to the 
upper seal-like marks of Z. sigillata of the Protolenus Zone 
(Div. 1 b. 3). 
Size.—Length, 4 mm.; width, 35 mm.; height of one valve, 
about 4 mm. 
Horizon and Locality.—In the fine olive gray shale of Div. 1 ¢ 
at Hanford Brook, 8. Martin’s. 
This species is something like that which Mr. C. D..Walcott 
refers to Nothozoe Vermontiana, but has a longer hinge line and 
is more triangular in form; it is also much flatter than that 
species. Its long hinge line and hinge plates show it to be of 
the genus Lepiditta. 
OSTRACODA. 
After the abundance of individuals and the variety of form 
in the Ostracoda of the Protolenus Fauna, the few found in 
the Paradoxides bed is somewhat of a surprise. Perhaps the 
Agnosti so common in the fine shales of bands ¢ and d usurped 
the place of the Ostracoda. 
PRIMITIA, Jones. 
This genus is represented by more than one species in the 
rocks of the St. John group, and the author proposes to 
describe here a very tumid form, of which a few individuals 
have been found. 
PrimitTiA AcADICA (Plate XV., figs. 5a—c). 
Primitia Acadica, Trans. Roy. Soe. Can., vol. iii., pt. iv., p. 
pl. vi., figs. 22, 22 @ and b. 
Outline of the valves elliptical-oblong, with but very slight 
