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In 1855 Prof. G. C. SWALLOW indicated the occurrence of a new species of CONULARIA in the horizon of the Chemung group (Second Annual Report on the Geology of Missouri, Appendix, p. 218).

In 1856 Prof. E. EMMONS described Conularia Hudsoni, from the Utica slate (American Geology, vol. 1, p. 208).

In 1856 J. HALL described Conularia subulata, from the Carboniferous limestones (Trans. Albany Inst., vol. 4, p. 32).

In 1859 the same author described Conularia pyramidalis, C. Huntiana, C. lata and C.? [desiderata]; the first two species from the Lower Helderberg group, and the last two from the Oriskany sandstone (Paleontology of New York, vol. 3, pp. 347, 348, 479, 480, plates 62 A, 70 A and 111).

In 1860 MEEK and WORTHEN described C. subcarbonaria, from Keokuk limestone (Proceed. Acad. Nat. Sci. Phila., 1865, p. 253).

In 1860 G. C. SWALLOW described Conularia Marionensis and C. triplicata, from the Hamilton group, and C. Missouriensis, from the St. Louis (Carboniferous) limestone (Trans. St. Louis Acad. Sci., vol. 1, p. 637).

In 1862 C. A. WHITE described Conularia victa, from the Burlington group, and C. Byblis, from the Chemung group (Proceed. Boston Soc. Nat. Hist., vol. 9, p. 22). In 1863 G. C. SWALLOW described Conularia Osagensis, from the Keokuk limestone (Trans. St. Louis Acad. Sci., vol. 2, p. 98).

In 1865 A. WINCHELL described Conularia Newberryi, from the Waverly group Lower Carboniferous), (Proceed. Acad. Nat. Sci. Phila.).

In 1866 E. BILLINGS described Conularia asperata and C. splendida, from the Hudson River group (Catalogue of Silurian Fossils of Anticosti, page 21).

In 1868 J. W. DAWSON described Conularia planocostata, from the Carboniferous rocks of Nova Scotia (Acadian Geology, pp. 307, 308, fig. 117).

In 1869 J. M. SAFFORD described Conularia Gattingeri, from rocks of the of the Hudson River group (Geology of Tennessee, page 289).

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In 1871 F. B. MEEK described Conularia elegantula, from the Upper Helderberg group, and C. micronema, from the Waverly group (Proceed. Acad. Nat. Sci. Phila.).

In 1876 C. A. WHITE described Conularia molaris, from Devonian rocks (Proceed. Acad. Nat. Sci. Phila.).

In 1876 C. D. WALCOTT described Conularia quadrata, from the Trenton group (Desc. New Species of Fossils, in advance of the Report of N. Y. State Museum of Nat. History).

In 1876 J. HALL designated and illustrated Conularia Cayuga, C. continens, and C. crebristriata, from the Hamilton group, and C. congregata, from the Portage group (Illustrations of Devonian Fossils, descriptions of plates 28 and 29).

The geological distribution of these species is presented in the following table:

[graphic][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed]

Of these thirty-four species, fifteen are recognized as Silurian, nine of them occurring in the lower division, and three in each of the upper divisions. Regarding the Upper Helderberg, Hamilton, Portage and Chemung groups as Devonian, we have ten species in this period; and including the Waverly group with the Carboniferous limestones, we have nine species of CONULARIA in this division of the series.

In 1867 M. J. BARRANDE enumerated twenty-seven species of the genus as occurring in Bohemia; and in the Palæozoic formations of all countries, he enumerated eighty-three species, including one from the Lias (Système Silurien du centre de la Bohème, pages 24 and 30). In this catalogue, however, there are but fourteen species credited to the United States, while at this time we enumerate thirty-four. The species of this genus described from the rocks of this country have been more than doubled since that period, while the number of new forms added to the European list must, we presume, proportionally far less.

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CONULARIA UNDULATA.

PLATE XXXIII, FIGS. 1–5, 7; AND PLATE XXXIV A, FIGS. 1-4.

Conularia undulata, CONRAD. Fifth Annual Report Pal. State of N. Y., p. 57. 1841.

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Hall: Descriptions of New Species of Fossils, etc., p. 34. Fifteenth Rep. N. Y. State Cab. Nat. Hist., p. 62. 1862. Illustrations of Devonian Fossils: Pteropoda, pl. 5. 1876. grandis, FERD. ROMER. Lethea Geognostica II Lief, p. 434, plate 3, fig. 21; and plate 1, fig. 12. 1857. "Distinguished from C. quadrisulcata by having the striæ more crowded and undulated, and by the absence of lines crossing the furrows between the striæ."

FORM elongate-pyramidal, with a quadrangular base. Transverse section quadrangular, rhomboidal, with the faces subequal (equal?); angles indented by the longitudinal grooves. Faces of the pyramid slightly convex in well-preserved specimens, often entirely flat, or sometimes concave, the proportions modified from pressure; center of each face marked by a distinct shallow groove, along which there is a slight deflection of the transverse striæ. Angles of the pyramid furrowed by a strongly marked groove, which is conspicuous in all conditions of the shell, and traversed by the surface-markings. Aperture of the fossil unknown. Summit

truncated by a convex septum in the best preserved specimens. Shell extremely thin; in most of the specimens entirely dissolved.

SURFACE, as determined from the best preserved specimens, and from external moulds, marked by fine transverse striæ, which, upon the sides, are gently curving towards the aperture, and slightly recurved in crossing the median groove; the striæ are interrupted by minute pustulose elevations, which give the surface (as seen under a strong lens, in its usual condition of preservation) a minutely crenulate or pustulose aspect. These elevations do not extend to the narrow interstriate spaces, which are apparently quite smooth, and about twice as wide as the elevated striæ, but vary with the growth and age of the shell.

In the harder and more arenaceous shales the fossil is often preserved in its natural proportions; but it is more frequently compressed, and, where occurring in the softer shales, is always flattened. The greater proportion of the specimens have the shell entirely dissolved (in none is there any portion fully preserved); and it is often difficult or impossible to discover the crenulate markings on the surface of the cast. Impressions of the exterior often show the punctate impressions of the slender striæ, while the interspaces appear as flattened, narrow, elevated bands, crossing the face of the fossil.

This species is distinguished from C. continens and C. congregata by the usually closer arrangement of the transverse ridges, and by the absence of striæ crossing the interspaces. The larger examples attain a length of about six inches, and the one figured on plate 33 has a length of 140 millimetres, with a width of about 40 millimetres at the base of the widest face exposed.

The specimen illustrated in figure 1, plate XXXIV A, is distinguished from the ordinary specimens of C. undulata by its more slender form, and more closely arranged transverse striæ, which are nodulose on their crests, with the interstriate spaces smooth, as in typical individuals of the species.

Formation and localities. In the coarser shales of the Hamilton group of New York, at Cazenovia, Hamilton, Schoharie; at Plainfield in Otsego county, and at Pratt's Falls in Onondaga county.

CONULARIA CRebristriata.

PLATE XXXIII, FIGS. 8, 9; AND PLATE XXXIV A, FIG. 5.

Conularia crebristriata, HALL. Illustrations of Devonian Fossils: Pteropoda, plate 29, figs. 8, 9. 1876.

FORM comparatively slender, regularly pyramidal, with a quadrangular base. Transverse section quadrangular with the sides unequal, the proportions being about as two to three; a part of this inequality is owing to a slight distortion through a compression of the specimen. Angles of the pyramid marked by a very distinct groove, which is crossed by the surface striæ. Faces of the pyramid somewhat concave, with scarcely a defined median groove, which in nowise affects the continuity of the transverse striæ. Aperture oblique. The summit has apparently been truncated by a septum.

SURFACE marked with very fine salient, distinctly nodose or pustulose striæ, which curve gently forward on the middle of the face; not interrupted by the median depression, and somewhat gently recurved over the convexity bordering the furrows at the angles of the shell, and continuous across the depression; spaces between the striæ about twice as wide as the striæ, and apparently free from ornamentation. The ornaments of the surface are only visible under a lens.

In some parts of the shell the striæ are much more closely arranged than in others an evidence of retardation in growth. In one specimen the striæ of the earlier growth, for at least one-third of the length of the shell, are much coarser than the later growth, and the change from the one to the other is quite abrupt.

This species is more slender in its mode of growth than C. undulata, and the transverse striæ finer, but the character of the ornamentation is precisely similar. Two specimens only, of this form, have been observed; one of these is a mould of the interior (the shell having been dissolved), which preserves the general form of the species; the other is, in part, an impression of the exterior in soft shale, preserving a portion of the interior surface of the shell.

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