. Maryland geological survey. re or less decurrent. This obliquity increasesproximad until finally the rachis may be bordered by long and narrowgradually decreasing wings, which in some specimens appear to be con-tinued downward beyond a fork. Occasionally pinnules higher up will(abnormally) show this alate character. Distad the pinnules becomereduced in size and more or less confluent, forming a lamina with ser-rate marginal teeth of greater or less incision. Texture very immersed. The midvein is prominent below and continues to 234 Systematic Paleontology the apex of the
. Maryland geological survey. re or less decurrent. This obliquity increasesproximad until finally the rachis may be bordered by long and narrowgradually decreasing wings, which in some specimens appear to be con-tinued downward beyond a fork. Occasionally pinnules higher up will(abnormally) show this alate character. Distad the pinnules becomereduced in size and more or less confluent, forming a lamina with ser-rate marginal teeth of greater or less incision. Texture very immersed. The midvein is prominent below and continues to 234 Systematic Paleontology the apex of the pinnule, although much diminished in calibre. The later-als branch at a wide angle and fork somewhat like those of Laccopteris;anastomosis has not been observed, however. The presence of dormantbuds at the ends of the primary axes has not been observed. Fructifi-cation characters unknown. This genus, of which the following species is the only one known, isclearly a member of the important Mesozoic fern alliance usually segre-. FiG. 3.—Sketch map of the world showing the Mesozoic and existing dis-tribution of the family Matoniacese. Circles = Upper Triassic, multiplicationsign =: Jurassic, plus sign = Lower Cretaceous, stars = Upper Cretaceous, en-closed dots show present occurrences. gated to form the families Gleicheniacege and Matoniacese,^ although theexact line of cleavage between the two, granting that there is such a line,has not been determined with precision for the existing, much less thefossil forms. The pseudo-dichotomy, which is such a characteristic ^Christ groups these two families in a separate class which he callsOligangia. Die Farnkrauter der Erde, Jena, 1897, p. 335. Maryland Geological Survey 235 feature of most of these ferns is rare in the other fern-families, and whenpresent is usually a variable and not a characteristic habit/ The genus, which is obviously unlike any previously known, is namedin honor of Dr. P. H. Knowlton, as a slight appreciation of t
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectpaleont, bookyear1901
