290 BULLETIN OF THE 
Verticordia Seguenze Datt. 
Shell having nearly the form of V. australiensis Smith (Chall. Lam., p. 167, 
pl. xxv. figs. 6-6 b), with thin rather convex valves, greenish color, and about 
forty radiating posteriorly convexly curved faint sulci, the interspaces between 
which are gently rounded but little elevated, and hardly to be called ribs, and 
have intercalary groovings toward the margin. The surface is covered with 
minute glassy grains arranged with some regularity in radiating and concentric 
series. As compared with V. australiensis the anterior dorsal margin is more 
elevated and rounded up; the posterior margin is less curved. V. trapezoidea 
Seguenza has the posterior dorsal margin much more curved, the anterior more 
oblique, and the hinge is different, putting it in another section of the genus. 
In V. Seguenze the ossicle is very small, flatter than in the typical species, 
rectangular, and wider behind; the length of the most perfect valve is 5.0, the 
altitude 4.0, and the diameter, taken as twice that of the single valve, would 
be 3.5mm. A large dead valve, perhaps of this species, was found at Station 
2602. 
Habitat. Yucatan Strait, 640 fms., one valve; U. S. Fish Commission, 
thirty-six miles south of Cape Hatteras, at Station 2602, in 124 fms., and about 
the same distance southeast of Cape Lookout, North Carolina, at Station 2614, 
in 168 fms., bottom in both cases sand, and bottom temperature about 61° F, 
(three valves). 
Although there is but little material, yet the species does not come very 
close to any of those with which I could compare it, and it seemed worthy 
of aname. The hinge, though delicate and with small teeth, is that of the 
typical Verticordia, 
Verticordia (Trigonulina) ornata D’Orsieny. 
Verticordia ornata Dall, Bull. M. C. Z., IX. p. 105, 1881. 
Trigonulina ornata D’Orb., Moll. Cuba, IL, p. 292, pl. xxvii. figs. 80-33, 1846. 
Verticordia celata Verrill, 1884; Trans. Conn. Acad., V.566; VL., pl. xxx. figs. 9,9 a. 
Habitat. Barbados, 100 fms.; Station 19, 310 fms. (Catalina Island, Cal., 
16 fms., Dall; Jamaica, W. I., D’Orb.; China Seas, Adams; east coast of the 
United States off the Carolinas, and northward as far as Station 949, off Mar- 
tha’s Vineyard, in 100 fms., U. 8. Fish Commission). 
The sculpture of this elegant species is composed of curved ribs, radiating 
from the umbones and crowded in front with two or more gaps behind. There 
may be a posterior rib forming the extreme margin, or the hindermost rib may 
be within the margin, two cases figured by D’Orbigny; or the posterior ribs 
may fail altogether, forming the variety celata Verrill. The ribs may all or in 
part be grouped in pairs, or the pairs may resemble a wide rib deeply grooved 
along its summit. The ribs may be high and strong, or low and uniform; in 
