. Annual report of the regents of the university of the state of New York on the condition of the State Cabinet of Natural History and the historical and antiquarian collection annexed thereto. Science. GENUS ZYGOSPIRA AND ITS RELATIONS TO ATRYPA. 267 VIII. NOTE UPON THE GENUS ZYGOSPIRA AND ITS RELATIONS TO ATRYPA. In the Thirteenth Report on the State Cabinet, page 69, I called attention to the existence of internal spires in the fossil known as Atrypa modesta ( Producta ?nodesta, Say, sp.), which appear to be arranged as in Atrypa. Not being entirely satisfied with the observation I was then
. Annual report of the regents of the university of the state of New York on the condition of the State Cabinet of Natural History and the historical and antiquarian collection annexed thereto. Science. GENUS ZYGOSPIRA AND ITS RELATIONS TO ATRYPA. 267 VIII. NOTE UPON THE GENUS ZYGOSPIRA AND ITS RELATIONS TO ATRYPA. In the Thirteenth Report on the State Cabinet, page 69, I called attention to the existence of internal spires in the fossil known as Atrypa modesta ( Producta ?nodesta, Say, sp.), which appear to be arranged as in Atrypa. Not being entirely satisfied with the observation I was then able to make upon the few specimens available, I proposed to give some farther attention to the subject in the next Report. At the same time I'added a note, asking for information or specimens that might aid in the elucidation of this and other forms. Dr. Rominger, of Ann-Arbor, Michigan, responded very generously to my request; but it was not until the Fifteenth Report (1862), that I was able to give the illustrations of the internal structure in a satisfactory manner. In this Report, I remarked that " the " direction of the spires is nearly the same as in Atrypa, differing in the "presence of the strong loop ; while the shell, in its exterior character, " is quite unlike ; I gave the* following generic description : Genus Zygospira ; Shells bivalve, equilateral, inequivalve : surfaces plicate in the typical species ; a sinus in the dorsal valve. Internal spires arranged somewhat as in Atrypa, with a broad loop passing from the outer limbs of the spiral band entirely across from side to side, near to or above the centre, and close to the inner side of the dorsal valve. The following illustrations, figs. 1 and 2, were given in the same con- nexion. Fig. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not pe
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Keywords: ., bookcentury1800, bookdecade1850, booksubjectscience, bookyear1853
