CLASS PELECYPODA 
103 
Subgenus Plectodon Carpenter, 1864. 
Leiomya scabra Carpenter, 1864. 
Plate 54, fig. 4. 
Suppl. Rep. Brit. Assoc., 1864, p. 638. Proc. Cal. Acad. Sci., 3:207. 
PI. t. ledae-formi, tenui, subdiaphana, pallida; tota superficie minute 
pustulosa; marginibus dorsalibus rectis, ad angulum 150°; antice et 
ventraliter producta, marginibus excurvatis; postice valde rostrata, trun- 
cata: intus, margine sub umbones interrupto; plica ex apice oblique ad 
marginem dorsalem anticum excurrente; dentibus lateralibus laminatis, 
extantibus, postico longiore; cicatri-cibus adductoribus parvis, subrotun- 
datis, ad extremitates dentium lateralium sitis; sinu palii lato, haud im- 
presso. Long., .62; lat., .34; alt., .20. (Carpenter.) 
Shape of Theora: dorsal margins twisted-in spirally inside umbos. 
Lateral teeth laminated, with internal cartilage hidden, appressed. (Car¬ 
penter.) 
Described as Plectodon scaber, Carpenter. 
Type. Consisting of two right valves, in California State Collection. 
Type locality, Catalina Island in 40-60 fathoms. 
Range. Puget Sound to San Diego, California. 
Family VERTICORDIIDiE. 
Genus VERTICORDIA Wood, 1844. 
Shell suborbicular, with radiating ribs; beaks subspiral; margins 
denticulated; interior brilliantly pearly; hinge with one prominent cardinal 
tooth in each valve; adductor scars two, faint; pallial line simple; ligament 
internal, oblique; epidermis dark brown. 
Type. Verticordia cardiiformis Wood. 
Distribution. China Sea, Mediterranean, Pacific Coast of the United 
States, Japan, Antilles. 
Range in time. From the Miocene. 
Verticordia ornata Orbigny, 1846. 
Plate 54, figs. 15 to 18. 
Moll. Cuba, 2:292; pi. 27, figs. 30-33. 
Shell small, suborbicular, compressed, thin; beaks subcentral, subspiral, 
small, sharp, anterior extremity evenly rounded; posterior dorsal margin 
evenly arcuate, and joining arcuate ventral margin in an angular extrem¬ 
ity; surface with nine prominent, sharp, arcuate, radiating ridges; the 
first and third interspaces wider than the others; margins sharply denticu¬ 
late; hinge with one prominent cardinal tooth in each valve; adductor 
scars two, faint; pallial line simple; ligament internal, oblique; interior 
pearly. Length, 4; height, 3.5; diameter, 2 mm. (Arnold.) 
