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GLYPTOCRINUS SIPHONATUS, (n.s.)

Description. Body large, broadly obovate, the greatest
width being above the origin of the arms; calyx narrow below,
spreading gradually to the bases of the arms; dome inflated on
the anterior (?) side. Arms rising from body in pairs with
deep constrictions between; arrangement and forms of plates
of calyx not fully determined; those of the dome are small
and polygonal.
The above description is drawn from internal casts. This
species differs from G. nobilis in the much greater length of
calyx which is not contracted in the lower part; while in that
species it is broad and spreading. It appears not to have had
a proboscis; but in the casts there is the filling of a cavity
which has passed from the summit of the dome between the
postero-lateral arms, where it turns outwardly, as if it had
opened on the exterior surface in the form of an oval opening.
Geological Formation and Locality. In rock of the age of
the Niagara group; Racine. Wisconsin. Dr. P.R. Hoy, T.J.
Hale, James Hall.

GENUS BALANOCRINUS, TROOST.
BALANOCRINUS INFLATUS, (n.s.)

Description. Body below the arms subturbinate, with sides
somewhat inflated in the lower part; arm bases prominent,
leaving deep interbrachial spaces; dome low, strongly inflated on
the oval side, surmounted by a slender sub-central proboscis.
Basal plates small, penagonal. Sub-radial plates proportionally
large, hexagonal. First radials heptagonal, a little larger than
the sub-radials; the form of the second and third radials un-
determined; the second are as large as the sub-radials; the
third very small.
Interradial plates, six; the first hexagonal, as large as the
second radials, with two in the second range, and three in the
third range, uniting with the dome plates. Anal plates numer-
ous, form and arrangement unknown.
The above descriptions have been drawn from the internal
casts of several specimens, which exhibit the divisions of the
plates.
This species differs from B. sculptus, Troost; Lampterocrinus
tennesseensis, Roemer "Silurian Fauna of Western Tennessee,"
in being more distinctly turbinate or obconical; in the deeper
interbrachial spaces; and the inflation of the dome on the an-
al side.