. Bulletin - New York State Museum. Science. 262 NEW YORK STATE MUSEUM from the Falkland Islands, Bolivia and South Africa and that others, principally the smaller forms express the local value of S. murchisoni. There are excellent reasons for these views, and though shells like S. primaevus var. atlanticus are ap- parently absent from the New York province yet there is no wide divergence between them and the larger examples of S. mur- chisoni. It will be understood that a proper interpretation of the congeries passing as S. murchisoni in the Oriskany is possible only in terms of well defined
. Bulletin - New York State Museum. Science. 262 NEW YORK STATE MUSEUM from the Falkland Islands, Bolivia and South Africa and that others, principally the smaller forms express the local value of S. murchisoni. There are excellent reasons for these views, and though shells like S. primaevus var. atlanticus are ap- parently absent from the New York province yet there is no wide divergence between them and the larger examples of S. mur- chisoni. It will be understood that a proper interpretation of the congeries passing as S. murchisoni in the Oriskany is possible only in terms of well defined localized expressions. Lower Devonic. Baker Brook point, Moosehead lake, Me. Cyrtina chalazia nov. We are presented in these shells with a departure from the usual aspect of the Devonic Cyrtinas. They are mostly multiplicate shells and in the early stages of this time conform quite generally to the same expression in contour, size and ribbing. Here we have a pauciplicate shell, the dorsal valve of which presents the characters. Cyrtinachalazia which we have noticed as a feature of Spirifer plicatus of the Grande Greve Jimestones; few, broad and blunt ribs. The shells are of the small size quite characteristic of the genus with trihedral form and erect or but very slightly curved cardinal area, flat dorsal valve, median sinus and fold well developed, the former having the width of the next two adjoining lateral plications. There are four to five plications on each ventrolateral slope and three to four on the dorsal, the ones nearest the hinge being always very faint. These are in the main broad and smooth and concentric growth lines are usually crowded near the front margin. Lower Devonic. Dalhousie, N. B. Trematospira perforata Hall var. atlantica nov. Species of Trematospira are almost exclusively of Helderbergian age and the species described are pretty well defined on the basis of their sculpture. In the form before us we have one more nearly. Please note that these images a
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