Geological Survey of Illinois, Том 2State journal steam Press, 1866 |
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Acad Actinocrinus Alethopteris anal pieces anal plate angle angular aperture arched arms basal pieces base beaks body whorl breadth Brgt Carboniferous central CLADODUS Coal Measures columella compressed concave convex costæ Crinoids crown curved denticles diameter differs distinct dorsal figures flattened Formation and locality Foss fossil genus Goniatite Grundy county height HELODUS heptagonal hexagonal hinge Illinois inch interradial Keokuk Keokuk limestone Koninck lateral left valve length Lepidodendron less Locality and position longitudinal Lsqx margin Mazon creek McCoy median cone MEEK and WORTHEN middle narrow Naticopsis nearly Neuropteris oblique obtuse outline Pecopteris pentagonal Philad pinnules posterior face primary radial proboscis Prof prominent radial pieces rays ridge rounded second radials seen shell showing Side view sinus siphuncle slightly smaller smooth specimen spines striæ striated Sub-carboniferous subradials summit superior sloping surface markings suture teeth tooth transverse truncated tubercles typical species umbilicus upper
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Стр. 325 - ... Designated by Meek and Worthen (1866, p. 333) and By SA Miller (1889, p. 514). Range. — Lower Carboniferous to Permian (?). Remarks. — Our knowledge of the genus Streblopteria is most unsatisfactory. McCoy described the hinge as having "one short narrow tooth slightly diverging from the hinge line in the posterior side of the beaks ; ligament confined to a narrow, simple facet on the hinge-margin.
Стр. 271 - Plates of the under side of the disc, very much smaller than the adambulacral, closely crowded together, and owing to their imbricating arrangement, presenting much the appearance of the scales of a fish; immediately on each side of the rays, they imbricate towards the latter, but near the middle of the space between any two ambulacra, the imbrication is inwards towards the mouth, so that in tracing the rows parallel to their longer diameter, across- between the rays, they are found to describe a...
Стр. 144 - Figs. 22, 28, 24, 26, 26, 27, 28. "Small, subglobose or obtusely subturbinate ; irregularly rounded and apparently retaining remains of a scar of attachment at the base. Cells four or more, rounded, conical, of moderate depth, and rather irregularly disposed. Surface striae rather distinct and broken up into irregular granules. Length or height about 0.48 inch ; greatest transverse diameter, about 0.43 ; breadth of cells nearly 0.18 inch. Locality and position ; Rockford, Indiana, Goniatite bed of...
Стр. 340 - P. subcuneatus, not only in attaining a much larger size, but in its distinctly sinuous instead of convex basal margin; also in the presence of radiating postero-dorsal costse.
Стр. 316 - Of these plications there are two, rarely three, on each side of the larger and more prominent one forming the mesial fold on the dorsal valve, while on the ventral valve there are three, rarely four, on each side of the mesial sinus ; a few zigzag marks of growth also traverse the anterior and lateral margins of the valves, parallel to their deeply notched edges.
Стр. 415 - FOSSIL PLANTS, AN ENUMERATION OF THE FOSSIL PLANTS FOUND IN THE COAL MEASURES OF ILLINOIS, WITH DESCRIPTIONS OF THE NEW SPECIES. FIRST DIVISION.— FERN LEAVES. Genus NEUROPTERIS, Brgt. Frond pinnately or bitripinnately divided ; pinnules or leaflets cordate at the base, or nearly so, rarely narrowed; entire or cut-toothed, lanceolate, broadly oval, round, kidney-shaped, etc., joined to the rachis by the middle or the base of the medial nerve, which is sometimes elongated into a short pedicel. Nerves...
Стр. 370 - The shell upon which we proposed to found this genus has much the appearance of a Murchisonia, but differs in being entirely destitute of a spiral band, or a sinus in the lip, as in that genus and Pleiirotomaria — the lines of growth being distinctly seen crossing the carinse, and the spaces between, without making the slightest curve.
Стр. 390 - Natatory abdominal appendages long and slender; styliform pair with first segment short and quadrangular ; second and only other joint (double?) with each branch (if there are two) simple, equal and as long as the telson, which they nearly exactly resemble in form ; their upper and lower margins each with a row of short, oblique, rather distant setae, between which may be seen, by the aid of a magnifier, a series of much more minute, closely-arranged setae. Telson as long as the last four abdominal...
Стр. 340 - ... posterior muscular impression. Beaks depressed upon a line with the dorsal margin, small, somewhat compressed, and placed about one-ninth the entire length of the shell behind the anterior margin. Scar of the anterior adductor muscle deep, trigonal-subovate, pointed above, and strongly defined by the prominent vertical ridge just behind it; those of the pedal muscles small, nearly marginal, and located directly over the anterior adductors; posterior adductor scars larger and more shallow than...
Стр. 139 - ... nigrum; below the margin of the lid this is interrupted by a discoid spot of the form and dimensions of an iris, which presents a median lenticular vacuity, again revealing the pigment, obviously the vertical pupil of a nocturnal animal. The preservation of the outline of color is certainly remarkable in a specimen of such great antiquity. A somewhat parallel case occurs in the preservation of the ink-bags of the Sepise; but these do not date further back than the Jurassic.