This is Mazon Monday post #109. What's your favorite Mazon Creek fossil? Tell us at email:[email protected].
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Today, we are looking at one of the rarer forms of Pecopteris, namely Pecopteris notata. This variety doesn't show up in a few of the Mazon Creek plant books, but it can be found in the new "A Comprehensive Guide to the Fossil Flora of Mazon Creek" by Jack Wittry.
Lesquereux in 1864, from Wikipedia
P. notata was described by Leo Lesquereux in 1858. He described much of the North American Carboniferous flora in the mid 1800's as a consultant to various US state geological surveys. His book "Atlas to the Coal Flora of Pennsylvania and the Carboniferous Formation throughout the United States" written from 1879 to 1884 was the standard reference for the Carboniferous flora in the US for many years. In 1870, he co-authored a book with Amos Henry Worthen called "Report on fossil plants of Illinois", which can be found on the Smithsonian's website. Worthen was the first curator of the Illinois State Museum.
Pecopteris notata Lesquereux, 1858
1858. Pecopteris notata Lesquereux: p. 866, pl. 18, fig. 4
1880. Pecopteris notata Lesquereux: p. 262
1889. Pecopteris notata Lesquereux; Lesley: p. 607, pl. no numberDESCRIPTION: The penultimate pinnae are lanceolate, taper gently to blunt lobes at the apices, and have channeled rachises. The ultimate pinna is nearly linear, with six to eight pairs of pinnules attached to a flexuous rachis. It has a large and blunt terminal pinnule at its apex. The pinnules are oblique, obtuse, ovate, about 5 mm long, and are confluent for half of their length. They are decurrent and have a small sinus on the acroscopic side. The venation consists of a thin, decurrent midvein that forks before reaching the apex. The lateral veins are thin, distant, and simple or divided once near the middle. The pinnules are punctate, which appears to be evidence of glands. The pits are randomly placed, small, and of various sizes and shapes.
REMARKS: Pecopteris notata is rare. This taxon is very similar to Pecopteris subcrenulata, but P. notata has shorter and wider pinnules and more distant ultimate pinnae. Most known examples in the Mazon Creek flora are from the Pit 15 area (see Fig. 2 on p. vi).
Specimens
From "A Comprehensive Guide to the Fossil Flora of Mazon Creek" by Jack Wittry.
From the Field Museum website
Recently collected specimen from ESCONI member Rich Holm. A single pinnule recovered from Pit 11.
