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PLEUROTOMARIA ABRUPTA, (N. s.) Description-Sub-lenticular, with a broad vertical band beneath the outer edge; whorls four or five, slender, sub-cylindrical, convex above and below. At the upper outer angle of the whorl a rather strong rounded ridge follows all round, and beneath it a flat or slightly concave vertical band, which at the aperture is one line wide in a specimen nine lines in width, below the band, the whorl is regularly convex. The umbilicus is about one third the width of the shell. Surface unknown.

Differs from R. aperta and R. calcifera in the vertical outer side of the body whorl.

I have seen no perfeet specimens of this species but such as we have clearly indicate its distinctions.

Locality and formation.—Mingan Islands, White Limestone. Collectors.—Sir W. E. Logan, J. Richardson.

PLEUROTOMARIA MISER, (N. s.)

Description.—This species is closely allied to R. abrupta but differs therefrom in having the lower side of the body whorl sharply augulated in the middle and also in the presence of an obtuse carina about the middle of the upper suface of each volu. tion. Judging from the form of the fragments of the whorls the aperture must be sub-pentagonal. It is evidently a smaller species than any of the others; width of largest specimen seen, five lines.

Locality and formation.—Mingan Islands, White Limestone. Collectors.—Sir W. E. Logan, J. Richardson.

PLEUROTOMARIA LAURENTINA, (N. s.) Description.—Lenticular, spire depressed, whorls five or six, on their upper sides slightly convex, but with a shallow concave band just within their outer margin. The lower side of the body whorl is a little concave just beneath the margin, then moderately convex to the umbilicus within which it is rather narrowly rounded. The umbilicus is deep and one fourth the whole width of the shell. The cast of the interior exhibits an acutely rounded margin, which, owing to the concave band above, appears to be turned a little upward, or to have a narrow ridge all round on its upper side. The aperture is sub-rhomboidal, the inner upper side slightly indented by the penultimate whorl. Width of largest specimen two inches and one fourth, height not

quite half the width in some of the specimens and more than half in others.

Associated with the larger are others almost an inch wide, with the whorls more convex below, but presenting no other differences so far as I have been able to observe. I think they are of the same species.

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Fig. 6. a Pleurotomaria Laurentina. View of the spire. The specimen

is a cast. bmc Side views of two specimens. d A large imperfect cast.

This species is allied to R. lapicida, Salter, but differs in having the whorls gently convex above, and in the form of the aperture which in that species is acutely oval, while in this it is subrhomboidal. The outer angle of the aperture of R. lapicida, measures about 75°, but in this species it is more than 90°.

The two species are most closely related, and it is not improbable that intermediate forms may yet be found to connect them.

Formation and Locality.—Mingan Islands, Calciferous Sandrock and White Limestone.

Collector.-J. Richardson.

PLEUROTOMARIA GREGARIA. (N. s.)

Fig. 8—h, k. Description.-Shell, small; spire conical; apical angle about 450 ; whorls, three or four, with a very narrow spiral band, which, on the body whorl, is rather above the middle of the volution, but in the upper whorls is situated on the lower Outer side at about one fourth the heighth. In full-grown specimens there is an obscure carina on the body whorl, one fourth of a line above the spiral band, and another close to the suture; the space between these two carinæ is flat or slightly concave; half a line below the band there is a third carina, scarcely visible, and below this the whorl is rounded ventricose. There is a small umbilicus. Length of shell, four lines ; greatest width, two lines and a half. Surface minutely striated.

Locality and formation.—St. Anns and near St. Eustache, extremely abundant, Calciferous sandrock. Collectors.—A Murray, J. Richardson.

TROCHONEMA TRICARINATA. (N. s.) Description.—Depressed turbinate ; whorls, four; with three carinæ, two of which are on the outer edge of the body whorl, and of these one is lost in the suture above. The third carina is on the upper side of the whorl, about the middle, but rather nearer the suture than the outer edge. The spaces between the carinæ, are concave; base depressed convex not carinated.Width of only specimen collected, nine lines.

At first sight this species appears to be the widely known T. umbilicata, (Hall) but differs therefrom by having only three carinæ.

Locality and formation.—Mingan Islands, Calciferous sandrock. Collectors.—Sir W. E. Logan, J. Richardson.

OPHILETA COMPACTA. (Salter). 0. COMPACTA. (Salter). Canadian Fossils Decade, 1, p. 16, pl. 3.

This species occurs near Beauharnois, near the Village of St. Eustache, and also at Romain's Island.

HELICOTOMA UNIANGULATA. (Hall.)

EUOMPHALUS UNIANGULATUS. (Hall). Palaeont, N. Y., vol. 1,

p. 9, pl. 3, fig. 1, 1 a. Occurs at Romain's Island.

HELICOTOMA PERSTRIATA. (N. s.) Description.—One inch and a half wide; whorls, three or four, with a strong carina on the upper side near the suture, another near the outer margin, and, apparently, several smaller ones below on the outside of the outer volution. The spaces between

these large carinæ with numerous coarse longitudinal striæ following the whorls to the apex. The lower and outer side of the whorls are regularly convex, and the umbilicus one third of the width of the whole shell,

This species is about the size of H. uniangulata and also of H. planulata, the spire a little more elevated than that of the latter, while the upper surface, in addition to the two keels, is ornamented with the longitudinal spiral striæ, which occur only on the outer side of H. planulata, and not at all on H. uniangulata.

Locality and formation.—Mingan Islands, White limestone. Collectors.—Sir W. E. Logan, J. Richardson. .

MACLUREA MATUTINA. ? (Hall). MACLUREA MATUTINA, (Hall). Paleont., N.Y., vol. 1, p. 10,

pl. 3, fig. 3.

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The specimen above represented agrees in its proportions very closely with those figured by Professor Hall. On referring to the plate cited, it will be seen that the figure shews two imperfect specimens, a small one with two whorls, and a larger one with nearly three. Ours agrees almost exactly with the smaller and also with the first two whorls of the larger. I think it highly probable that when good specimens can be compared, those of New York will be found identical, and I shall not therefore propose another name for ours.

Locality and formation.—Mingan Islands, Calciferous sandrock.

Collectors.—Sir W. E. Logan, J. Richardson.

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Fig. 8.
a Murchisonia Anna.
bme Small specimens supposed to be of this species.
g Murchisonia linearis.
h-k Pleurotomaria gregaria.
i Eunema prisca.

Fig. 8.—a, d. Description.—Elongate, apical angle about 20°; whorls, ten or twelve, flattened in their upper two-thirds, rounded near to and into the suture. About the middle of the lower half of the whorl there is a narrow flat spiral band, which, on the body whorl of large specimens, is one line or a little more in width, but becomes gradually narrower to correspond with the decreasing dimensions of the upper whorls. The fine striæ are most conspicuous on the upper part of the whorl, their course being from the suture downward, and backward with a sigmoid curve to the band. On some of the specimens there are also numerous undulations in the shell which follow the course of the striæ. Length of full grown specimens, about three inches; but accompanying these there are multitudes of smaller ones of all sizes, from the length of two lines to two inches. Many of these small ones have the whorls nearly regularly convex and may constitute new species; but, at present, I think they are only the young.

This species, especially in the small specimens, somewhat resembles M. gracilis, (Hall) but is easily distinguished therefrom by the flatness of the upper part of the whorls. It is more closely

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