74 PALAONTOLOGY OF NEW-YORK. 
perfectly preserved, we are able to decide that they differ from Escuara and Fiustra, with 
which they seem to be closely allied, as well as with Cerropora in some instances.* We 
are able to characterize several species, depending for their distinction partly on their mode 
of growth, and partially upon the arrangement of the cellules upon the surface. 
113. 5. STICTOPORA? ACUTA. 
Pu. XXVI. Figs. 3,5. 
Compare Eschara ? sealpellum. LonspA.se in Silurian System, pag. 679, pl. 15, fig. 25, 25 a. 
Branches numerous, bifurcating, celluliferous on both sides ; cells oval, nearly opposite 
on the two sides ; outer rows of cells sometimes smaller and less distinct ; margins of the 
coral solid, smooth and sharp on the edges. 
The branches are marked by from seven to nine rows of oval cells, which, when perfect, 
are surrounded by an elevated border. The coral is usually so much worn that the edges 
of the apertures do not rise above the surface of the branches. 
In general form and appearance, this species resembles the S. ramosa of the Black-river 
limestone ; but on a careful examination, it proves clearly distinct. The number of rows 
of cells is fewer, and the cells larger ; the edges of the branches are solid, smooth and sharp, 
while in that species the cells extend entirely to the margin. The most essential difference, 
however, is the apparent absence of an axis in this species ; while the S. ramosa, as the 
other species of the genus, is separable into a thin celluliferous crust from each side, 
between which is a thin flat axis. 
This species is placed provisionally under the Genus Sticropora, from its general analogy 
of form and mode of growth; but a further examination may make it necessary to remove 
it to the Genus Escuaropora, from the structure of the axis, which appears to be inseparable 
from the celluliferous crust. 
* Mr. Dana, to whom I have submitted the examination of some of these species, suggests that S. ramosa is rather 
nearer CeLLEPoR+ than Fuustra. He thinks that the open cell is owing (as in MeEmBraAnipPorA) to the exterior not 
having been calcareous (Letter to the Author, Aug. 19, 1846). The broad foliaceous expansions of S. labyrinthica 
bear some resemblanes to MemBrawniPorA, but the cells are not narrowed below. 
The Genus Ceriopora of Goipruss includes some forms ( pag. 217, pl. 65, figs. 11, 12 & 13), which are very 
analogous to our corals; but this genus is composed of heterogeneous materials, as is clearly proved by a reference to 
his figures and descriptions. A large number of the species given by Goupruss under this genus are distributed by 
other authors under ALveoLirss, CurysAoRE, HETERoPoRA, Pusruxipora and SpiniporA; leaving, among others 
under Ceriopora, several species very analogous, in the form and arrangement of cellules, to those I have placed 
under the proposed genus Sticropora. These, however, depart so widely from the type of the genus, according to 
the description of the author, that it appears preferable to arrange them under another term, by which, at least among 
the paleozoic fossils of the United States, it is believed that they can be readily recognized. 
The essential difference between this genus and Escuaropora, and which induces me to separate the two, lies in 
the existence of a thin foliaceous axis separating the bases of the cells in Sricropora, as shown on Plate iv. fig. 4, 
and Plate xxvi. fig. 4 d & f, and which does not exist in the typical species of EscHaropora; the cells, as in ramose 
forms of Favosires and other similar corals, radiating from an imaginary axis. 
