1 Pas GEOLOGICAL SURVEY OF THE TERRITORIES. 
striated ; interior of cells filled with a finely vesicular tissue; cups poly- 
gonal, concave, elevated in the center, and displaying numerous radial 
lamelle.” 
The calyces of the specimens discovered by Dr. Peale are a little 
smaller, and somewhat more irregular than those of the type specimens 
of L. typa used by Prof. Winchell in his description, and also of others 
which I have collected at the typical locality, near Burlington, Lowa, 
and the whole corallum is also a little more delicate. The differences 
between the two forms are very slight, however, but under the cireum- 
stances it is thought advisable to give a new specific designation to the 
form here especially considered, and in its selection to honor the name 
of the founder of the genus. It is proper to remark here that the coral- 
lum of this form appears to have been entirely free, as Dr. Winchell 
states his typical examples to have been, since the limestone matrix is 
in immediate contact with its under surface. A small example of this 
coral in the collection is evidently a young corallum. It consists of two 
minute calyces, and one large one, surrounded. by ten or eleven others 
of nearly full size. This seems to indicate that the increase of the coral- 
lum by added calyces was in all directions from the center, and that the 
natural tendency to increase was no greater in one direction than in 
another. 
Dr. Peale found only a part of the full Carboniferous series spored, 
or present, at the locality from which these specimens of Leptopora were 
obtained, and the fossils were found in strata near the base of that local 
series. He thinks the strata of that locality belong near the base of 
the full Carboniferous series; but, aside from the presence of Leptopora 
there is no paleontological evidence that they represent the Subcarbon- 
iferous Group, as separable from the remainder of the great Carbonif- 
erous series. On the contrary, some of the associated species have 
hitherto been found only in the Coal-measure strata of the Mississippi 
Valley. 
Figs. 12 a and J, on plate 34, are drawn from an authentic example of 
I. typa; and are introduced here for comparison, and to illustrate 
generic characters. 
The fossils found by Dr. Peale associated with the Leptopora here 
described, consist of a single example of Retzia (Humetria) uta Marcon, 
a small plicated, undetermined species of Rhynchonella, a broken stipe 
of Glauconome, like G. nereidis White or G. trilineata Meek, and a few 
segments of erinoid stems. 
In this instance there is plainly a commingling of Subcarboniferous 
and Coal-measure types; and, so far as the paleontological evidence 
yet obtained is concerned, we are not justified in referring the strata 
from which these fossils were obtained to either of those groups exclu- 
Sively. 
ECHINODERMATA. 
Genus PLATYCRINUS Miller. 
PLATYCRINUS HAYDENI Meek. 
Plate 33, fig. 7 a. 
Platycrinites haydeni Meek, 1873, An. Rep. U. 8. Geol. Sur. Terr. for 1872, p. 469. 
Only a single example of this species has been discovered, which Mr. 
Meek described as follows : ’ 
“A small species with a cup-shaped body, rounded below to a circular 
