A Critical Summary of Troost's Unpublished Manuscript on the Crinoids of Tennessee

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U.S. Government Printing Office, 1909 - Crinoidea, Fossil - 150 pages
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Page iii - The scientific publications of the National Museum consist of two series — the Bulletin and the Proceedings. The Bulletin, publication of which was begun in 1875, is a series of more or less extensive works intended to illustrate the collections of the United States National Museum and, with the exception noted below, is issued separately.
Page 46 - Of this species I have seen only one good specimen (and two inferior fragments which probably belong here). The frond is 6 cm. high and of still greater breadth. One of the branchlets of the dichotomous termination is much more slender than the other (a sort of lateral pustule). indicating probably the commencement of the growth of a new branch. The general form of this...
Page 183 - ADVERTISEMENT. The scientific publications of the National Museum consist of two series — the Bulletin and the Proceedings. The Bulletin, publication of which was begun in 1875, is a series of more or less extensive works intended to illustrate the collections of the TJ.
Page 21 - Frond circular, but cyathiform in its growing state. There are numerous bifurcating branches, which in the fossil condition imperfectly unite or overlie each other, producing a kind of fine network with irregular sub-rhomboidal (ellipsoidal) interstices. In texture it is corneous, having the branches marked with striations of the sub-rhomboidal form.
Page 39 - ... solid axis surrounded by their common canal, which is sometimes only represented by a central depression or elevation, but occasionally its form is well preserved. The rarely indicated cell openings are represented by minute oval depressions in the substance. The texture is highly corneous (or replaced by pyrites). "The diameter of the frond is 2 cm, and of the disk 1 cm; the radiating branches extend half a centimeter beyond the disk, and number between 25 and 30, but, as each is divided, the...
Page 58 - In occasional specimens of the same mode of branching, short spinelike processes, from one-half to one millimeter long and half a millimeter apart, probably indicate the position of the cellules on both sides of the branches. "There is considerable variation in the size of these organisms. The larger specimens are 4 or 5 cm. long, and the stipes are usually about 1 mm. thick. "FORMATION AND LOCALITY : Fragments of this species occur somewhat abundantly in the Niagara dolomitic rocks at Hamilton,...
Page 183 - RICHARD RATHBUN, Assistant Secretary, Smithsonian Institution, In charge of the United States National Museum. WASHINGTON, DC, December 1, 1911.
Page 40 - The texture of this coral is similar to the Graptolites, a black scaly crust or film being all that remains of the substance. From the specimens examined, It appears to have grown in groups, with rounded or flattened stems, which are dichotomons above and more or less spreading.
Page 44 - COPY OF SPENCER'S FIGURE. RULLETIN 65, UNITED STATES NATIONAL MUSEUM. branches averaging 2 mm. in breadth for the larger and 1 mm. for the smaller, toward the margin of the frond, where the branchlets end in two (sometimes three) extensions of unequal thickness. Texture corneous, with the surface composed of scaly fibers. Extending longitudinally through the stipes are central or subceutral elevations (sometimes depressions), indicating a solid central axis.
Page 12 - ... rather strongly radiate, with the branches usually about 0.8 mm. wide (a few as narrow as 0.6 mm., a few swelling out to 1 mm., particularly immediately below a bifurcation); about 15-17 in 25 mm. of width in the basal portion, and in young specimens frequently somewhat more slender, more tortuous (with slight tendency to zigzag) and somewhat farther apart; the interspaces consequently as wide as, or slightly wider than, the branches. Dissepiments mostly transverse (some are slightly oblique,...

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