486 
BULLETIN OF THE UNITED STATES FISH COMMISSION. 
valve with three cardinals, the posterior one bifid, with two faint anterior laterals separated by a deep 
pit; pallial sinus deep. Color violet and whitish, the posterior end often quite dark. 
Length, 50; height, 40; diameter, 28 mm. 
Fajardo, Porto Rico, two fine specimens. 
The spines are often somewhat curved; sometimes they are much reduced, so that they are in 
reality merely elevated scales. 
Subgenus Transennella Dali, 1883. 
Internal margins tangentially sulcate. 
Meretrix cubaniana d’Orbigny. 
Venus cubaniana d'Orbigny, Moll. Cubana, n, pi. xxvi, figs. 44-46, 1845. 
Shell rather small, triangular-ovate, solid, rather compressed, inequilateral, with high beaks, 
slightly turned forward over a large, well-defined lunule; surface covered with low, irregular, concen- 
tric ridges; left valve with three cardinals, the central tooth strong, and a high, compressed anterior 
lateral; right valve having the two anterior cardinals separated by a narrow fissure and two small 
anterior laterals with a deep pit between them; pallial sinus deep. Color white, generally with a few 
irregular brown markings. 
Length, 8; height, 6; diameter, 4 mm. 
Mayaguez, Porto Rico, a few worn valves. 
The internal margins of the valves are sharply grooved, but not in harmony with the lines of 
growth, which is the characteristic of this subgenus, of which the species are all small shells. 
Meretrix culebrana, n. sp. Plate 55, fig. 5. 
Shell small, solid, subtrigonal, with elevated beaks, nearly equilateral, moderately convex; 
periostracum rather thick, yellowish brown, paler on the umbones and posterior dorsal area; surface 
obsoletely minutely concentrically undulated, with a rather large, ovate-cordate, somewhat depressed 
lunule defined by a well-impressed line, but no perceptible escutcheon; form as figured; interior 
white; hinge strong, normal, a prominent, anterior lateral in each valve; pallial sinus subtriangular, 
rounded in front; marginal grooving well marked. 
Length, 7; height, 5.7; diameter, 3.8 mm. 
At station 6087, in 14 to 18 fathoms, coral sand, off Culebra Island, Porto Rico. 
A very pretty and characteristic species of this peculiar group, which can not be confounded 
with either of the other described species. 
Genus DOSINIA Scopoli, 1777. 
Shell suborbicular, compressed or slightly inflated, concentrically sculptured, with prominent 
beaks and a well-defined lunule; hinge with three cardinal teeth in each valve; left valve with an 
anterior lateral close to the front cardinal; right valve with two vestiges of anterior laterals; pallial 
sinus deep; border of the shell without crenulations. 
Dosinia elegans Conrad. 
Artemis elegans Conrad, Proc. Acad. Nat. Sci. Phila., vi, p. 320, 1853. 
Artemis concentrica Reeve, Conch. Icon., vi, pi. ii, tig. 8, 1850; not of Born, 1780. 
Shell suborbicular, rather solid, subtruncated posteriorly and almost angular at the posterior end 
of the ligament; lunule. small and distinct; ligament nearly immersed; beaks high and rather sharp, 
turned forward; surface covered with rather strong, close, concentric ridges and showing faint traces of 
radial sculpture on earlier growth; left valve having central cardinal wide and flattened, the anterior 
lateral small and tubercular; right valve with posterior cardinal bifid; beak cavities deep, compressed; 
muscle scars elongated, smooth ; pallial sinus deep, triangular. Color whitish ; epidermis straw-colored. 
Length, 75; height, 68; diameter, 30 mm. 
Playa de Ponce, Porto Rico, three dead shells. 
Genus MYSIA Leach, 1818. 
Shell suborbicular, concentrically striate, with a faint lunule and high beaks; hinge with two to 
three divergent cardinals in the right valve and three in the left; laterals wanting; pallial sinus large, 
subvertical. 
