DEVONIAN FAUNAS. 30 
Cs 
ORTHOTHETES WOOLWORTHANUS (Hall). 
Plate XXXIV., Figs. 4-5. 
See, also, p. 278, pl. XXVII. 
This species, as it occurs in the New Scotland beds, differs in no 
respect from the Coeymans limestone specimens. 
ORTHOSTROPHIA STROPHOMENOIDES (Hall). 
Plate XXXIV., Figs. 6-8. 
1859. Orthis strophomenoides Hall, Pal. N. Y., vol. III., p. 177, pl. 
14, figs. 2 a-l, pl. 23, figs. 7 a-g. 
Description.—Shell subquadrate in outline, regularly rounded in 
- front; hinge-line straight, a little shorter than the greatest width of 
the shell; cardinal angles obtusely angular. Pedicle valve depressed- 
convex on the umbo, flattened or slightly concave toward the lateral 
margins, with a narrow mesial elevation extending from the beak to 
the anterior margin, but becoming less sharply-defined anteriorly ; 
beak small, but shghtly elevated above the hinge-line; cardinal area 
narrow. Brachial valve much more convex than the pedicle, most 
prominent a little posterior to the middle, with a narrow and shallow 
mesial depression extending forward from the umbo, becoming 
broader and less sharply-defined anteriorly. Surface of both valves 
marked by fine, radiating plications, which increase by irregular bifur- 
cation and intercalation. When the surface is not exfoliated, rather 
strong, concentric, lamellose lines of growth are present. 
The dimensions of a nearly-perfect specimen are: length, 2 
wn 
conta 2 
width, 31.5 mm.; thickness, 15 mm. 
Remarks.—This species has been observed only in the shaley mem- 
ber of the New Scotland formation, and even there it is usually not 
a common species. The shell itself is frequently wholly destroyed, 
leaving the specimens in the form of casts of the interior, upon which 
the strong muscular impressions are a conspicuous character. 
Pix 
