This is Mazon Monday post #95. What's your favorite Mazon Creek fossil? Tell us at email:[email protected].
-----------------------------------------------------
After Lesquereux (1870)
For this post, we are looking at another seed fern species, Neuropteris vermicularis. N. vermicularis was identified by Leo Lesquereux in 1866. 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.
Lesquereux in 1864, from Wikipedia
In 1969, William Cup Darrah, a paleobotanist of some note, assigned various species of Neuropteris as forms of Neuropteris ovata, (see Mazon Monday #85). His reasoning was Neuropteris ovata is highly variable and N. vermicularis, and some other species of Neuropteris (N. flexuosa, N. plicata, N. gigantea, N. heterophylla, N. obliqua, N. loschi, and Mixoneura jenneyi) were best described as variable forms of N. ovata. This theory has been disregarded and most of these are still assigned as separate species.
From "ESCONI Keys to Identify Pennsylvanian Fossil Plants of the Mazon Creek Area"
In Jack Wittry's book "A Comprehensive Guide to the Fossil Flora of Mazon Creek", here is the entry for N vermicularis.
Neuropteris vermicularis Lesquereux, 1866
1866. Neuropteris vermicularis Lesquereux: p. 428
1870. Neuropteris vermicularis Lesquereux: p. 385, pl. 6, figs. 1-3
1879-80. Neuropteris vermicularis Lesquereux: p. 99, pl. 10, figs. 5-10
1925. Neuropteris ovata; Noé: pl. 20, fig. 3; non pl. 21, fig. 4 = ovata
1925. Neuropteris flexuosa; Noé: p. 14, pl. 20, fig. 1; pl. 23, fig. 3; non pl. 21, figs. 2, 3
1925. Neuropteris vermicularis; Noé: p. 14, pl. 24, fig. 1
1940. Neuropteris flexantea; Janssen: p. 91, pl. 25, fig. 2
1958. Neuropteris flexuosa; Langford: p. 202, fig. 358
1958. Neuropteris gigantea; Langford: p. 201, figs. 356, 357, 359
1958. Neuropteris tenuifolia; Langford: p. 211, fig. 365; non fig. 366, non text
1969. Neuropteris ovata forma vermicularis; Darrah: p. 107, pl. 2, figs. 1, 2
1979. Neuropteris gigantea; Janssen: p. 152, figs. 142, 143
1979. Neuropteris tenuifolia; Janssen: fig. 141, non textDESCRIPTION: The pinnae vary in shape from linear to linear-lanceolate or triangular, depending on placement on the frond. The rachis is heavy and straight. The pinnules are alternate, slightly oblique, and oblong. At the pinnule base, the basiscopic side has a small auricle; the acroscopic side is rounded. The venation is open near the midvein and fairly fine at the margins, with a count of 20 to 40 veins per centimeter. The midvein is strong at the base and disappears near the middle. The lateral veins are strong, arched, and divide twice or sometimes three times in more developed pinnules before meeting the margin. The terminal pinnule is lanceolate, longer than it is wide, symmetrical at the apex, and tends to become relatively smaller compared with the lateral pinnules as the pinnae become larger. The shape of the terminal pinnule base varies depending on the degree of separation of the nearest lateral pinnules.
REMARKS: Neuropteris vermicularis is very common. As can be seen in the synonymy list, this form has, for various reasons, been placed into several taxa. The most commonly misused name is Neuropteris gigantea, which is a Paripteris and is found only in older strata. Paripteris is characterized by paired pinnules at the pinna apex. This is unlike N. vermicularis with its single, large terminal pinnule. Also see Neuropteris ovata and Neuropteris flexuosa.
Specimens
