DALL: MOLLUSCA AND BRACHIOPODA. 401 
Both valves were originally covered with fine, concentric, umbonally inflected, 
concrescent lamellae, which are usually entirely cleaned off in cabinet specimens. 
Chiamys Botten. 
NODIPECTEN Dat. 
Pecten (Nodipecten) subnodosus Sowerrsy. 
Pecten subnodosus Sowerby, P. Z.S. Lond., 1835, p. 109; Thes. Conch., 1848, Pecten, 
p. 65, pl. 15, figs. 97, 112. 
Gulf of Tehuantepec, in 10-17 fathoms, Sowerby ; U. S. S. “ Albatross,” 
station 8368, near Cocos Island, in 66 fathoms, rocky bottom, temperature 
58°.4 F. U.S. N. Mus. 122,863. Also Gulf of California. 
PALLIUM ScuumacueEr. 
Pecten (Pallium) miser Da t, n. sp. 
Plate 8, figure 6. 
Shell small, flattish, dark reddish purple, with a narrow hinge line, striated disk 
and five strong radial ribs; anterior ear very short, oblique; posterior ear longer, 
triangular, with three radial threads near the hinge line, an excavated, concen- 
trically striated space between them and the edge of the disk; right valve with 
five, strong, rounded ribs with subequal interspaces, and two much smaller, 
closer, and less prominent, near the anterior submargin, and a single, similar riblet 
near the posterior submargin; ctenolium rather long with about five free hooks ; 
minor sculpture of the disk consisting of very numerous subequal radial threads 
with subequal interspaces crossed by still more numerous fine, imbricated, sharp 
lamellae which, when the surface is intact, coalesce, but when it is worn show as 
sharp concentric lamellae looped over sharp radial ridges with distinctly wider 
interspaces ; distal margin of the valve suddenly and markedly contracted in the 
adult; hinge line with strong plicae on each side of the cartilage pit, strongly 
vertically striated; interior smooth, ridged by the sculpture, livid purple with 
strong lirations near the valve margin, on the lateral margins of each rib; valve 
margin minutely crenulate. Alt. 34.0; lat. of valve, 32.0; of hinge margin, 9.0; 
diameter of right valve, 6.0 mm. 
U.S.58. “ Albatross,” station 3355, Gulf of Panama, in 182 fathoms, mud, 
bottom temperature 54°.1 F. U.S. N. Mus. 122,862. 
Only two upper valves of this species were obtained, but as it belongs to a 
group totally distinct from any other on the Pacific Coast, so far known, it can be 
recognized without difficulty. 
Pecten (Chalmys) pasca Da tt, n. sp. 
Shell (left valve) flat, irregular distally, rose-pink and white, irregularly 
clouded, somewhat inequilateral; anterior ear larger, with four crimson radial 
VOL. XLIII. — NO. 6 26 
