14 research outputs found

    Petrified Lepidophloios Specimens from Iowa Coal Balls

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    Examination of Iowa coal balls from the Des Moines Series has yielded two petrified stern fragments assignable to the arborescent lycopod genus Lepidophloios. Details of the leaf cushions and internal stem anatomy are described and compared with similar specimens from Kansas and Illinois coal balls. In light of these observations, criteria presently used to distinguish among species of Lepidophloios are re-examined. In particular, the diagnostic features of Lepidophloios kansanus (Felix) Eggert and L. pachydermatikos Andrews & Murdy are reviewed and determine to represent ontogenetic differences. The probable conspecific nature of the above taxa results in assignment of the Iowa specimens to L.kansanus sensu lat

    Two Species of Alethopteris From Iowa Coal Balls

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    Petrified specimens of Alethopteris sullivanti (Lesquereux) Schimper and Alethopteris lesquereuxi Wagner, species of Pennsylvania seed fern leaves, were found in coal balls from the Lovilia locality in south central Iowa. The morphology and anatomy of these leaves are described and are compared with findings of previous workers (Leisman, 1960; Baxter and Willhite, 1969). It is generally accepted that Alethopteris is a foliage type of the Pennsylvania pteridosperm, Medullosa (Scott, 1899; Steidtman, 1944). Evidence cited to support this includes the attachment of seeds to Alethopteris foliage (Halle, 1927), the common association of the genus with Myeloxylon, Dolerotheca, Pachytesta, and other organ genera of medullosan affinity, and the anatomical similarities of the leaves with Myeloxylon petioles (Leisman, 1960; Ramanujam et al., 1974). The genus, Alethopteris, was established by Sternberg in 1825 to describe a fern-like compression foliage. Most subsequent studies of the genus have been confined to compression material. A summary of this work is found in Wagner\u27s comprehensive monograph (1968). Alethopteris sullivanti (Lesquereux) Schimper and Alethopteris lesquereuxi Wagner are the only Pennsylvanian species of which the details of internal anatomy are known from petrified coal ball material (Leisman, 1960; Baxter and Willhite, 1969). Wagner (1968, pp. 16-17) believes that the classification of Carboniferous fern-like foliage into natural genera must be based on several different features. These are 1) the general morphology of the frond and its pinnae, 2) epidermal characteristics as preserved in cuticles, 3) fructifications, 4) pinnule morphology and ontogenetic pattern. Wagner feels that ultimately studies of cuticles will be particularly useful in establishing natural genera. This paper describes the morphology and anatomy of Alethopteris sullivanti and A. lesquereuxi leaves found in Iowa coal balls. It also includes a study of the cuticles of these species

    Living in a \u27Moffitt House\u27 16th Century - and Ahead of its Time

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