76 
PALAEONTOLOGY OF NEW-YORK. 
115. 2. GORGONIA PERANTIQUA. 
Pl, XXVI. Figs. 5 a , l . 
Coral consisting of numerous small branches proceeding from a central point; branches 
bifurcating, smooth, or very finely striated ; cellules arranged on two sides of the axis, 
opening laterally. 
The specimen consists of a number of lax branches, apparently diverging from a centre 
or point of attachment : these branches are several times subdivided, but present no evidence 
of connecting bars. 
The species is exceedingly rare, a single one being all that has fallen under my notice. 
Fig. 5 a. The specimen, natural size. 
Fig. 5 b. A portion of a branch enlarged, showing the openings upon the two sides of the axis. 
Position and locality. In the soft shaly layers of the lower part of the Trenton limestone, 
near Middleville, Herkimer county. 
116. 1. AULOPORA ARACHNOIDEA. 
Pl. XXVI. Figs. G a, b, c. 
Coral consisting of a fine weblike expansion, diffusely branching and anastomosing, 
attached to the surface of other bodies ; tubes narrow, slender, short, subclavate or straight, 
single ; mouth slightly elevated, opening oblitprely upwards, smaller than the cell below. 
This very delicate species, in some portions of its extent, bears considerable resemblance 
to Alecto dichotoma of the Jura limestone ( Lamouroux, Exp., p. 84, t. 81, f. 12 - 14 ; 
Blainville, Man. d’Act., p. 464, t. 65, f. 1 ; Aulopora dichotoma , Goldfuss, Petrefada , 
pag. 218, pl. 65, fig. 2); but other portions develop a structure scarcely compatible with 
this genus, and I have therefore placed it under the Genus Aulopora. The illustration 
below presents a magnified view of a distinct part from that shown on the plate, and 
exhibits the essential characters of Aulopora.* It is the only species of the genus known 
* A magnified portion of this fossil, a part of which (a) shows the character of Aulopora, while other portions 
(6) more nearly resemble Alecto. 
