_Barnegat City_ (female).—Five segments. Manubrium wider than long,
convex inferiorly. Deep anterior and posterior notches, about equal, the
former with an angular projection on each side. Facet for cartilaginous
sternal rib thick and prominent. Second segment wider than long, about
equally notched anteriorly and posteriorly, the two sides anchylosed
together by a bony bridge, about as wide as the notches are deep. Third
and fourth segments similar to second but smaller; similarly notched;
left portion a little longer than right. Fifth segment elongated, left
side very much so; the two sides joined by a narrow bridge; posterior
notch very deep.
_Newport_ (male).—Similar to sternum of Barnegat skeleton, but manubrium
scarcely wider than long; posterior notch much longer than anterior, with
parallel sides. Second and third segments similar to those of Barnegat
skeleton but sides of latter not completely anchylosed together. Fourth
segment in two pieces, with a wide interval between. Fifth segment
triangular with deep anterior, triangular notch, a narrow bridge, and
short posterior prolongation (the left longer than the right).
_Charleston_ (female, jr.).—Resembles the sternum of the Barnegat
skeleton rather than that of Newport skeleton, but anterior parts
cartilaginous. Opposite sides of second, third, and fifth segments
anchylosed together and those of fourth segment nearly so. (Pl. 25, fig.
2).