Opening the text

Fossil plants, Vol. 2 : $b A text-book for students of botany and geologySeward, A. C. (Albert Charles)

Science

Fossil plants, Vol. 2 : $b A text-book for students of botany and geology

Name: Fossil plants, Vol. 2 : $b A text-book for students of botany and geology
Author: Seward, A. C. (Albert Charles)

Seward, A. C. (Albert Charles)

Paleobotany

Certain species of _Pecopteris_ fronds from Carboniferous strata
are characterised by circular sori or synangia consisting of a
small number (3–8) of exannulate sporangia attached to a central
receptacle and free only at their apices. Strasburger[997] suggested
a Marattiaceous affinity for _Asterotheca_ and Stur[998] describes
the species _Asterotheca Sternbergii_ Goepp. (fig. 291, C, D) as an
example of a Marattiaceous fern. The latter author retains Corda’s
genus _Hawlea_[999] for the fertile fronds of the common Coal-Measures
species _Pecopteris Miltoni_, while on the other hand Kidston[1000]
includes this type in _Asterotheca_.


_Pecopteris_ (_Asterotheca_) _Miltoni_ (Artis).

  1825. _Filicites Miltoni_, Artis, Antedil. Phyt. Pl. XIV.

  1828. _Pecopteris Miltoni_, Brongniart, Prodrome, p. 58.

  1828. _Pecopteris abbreviata_, Brongniart, Hist. vég. foss. p. 337,
        Pl. CXV. figs. 1–4; Lindley and Hutton, Foss. Flor. Vol. III.
        Pl. 184.

  1845. _Hawlea pulcherrima_, Corda, Flor. Vorwelt, p. 90, Pl. LVII.
        figs. 7, 8.

  1877–1888. _Hawlea Miltoni_, Stur, Culm Flora, p. 293; Farne Carbon.
        Flora, p. 108, Pls. LIX. LX.

  1888. _Pecopteris_ (_Asterotheca_) _abbreviata_, Zeiller, Flor.
        Valenc. p. 186, Pl. XXIV. figs. 1–4.

[Illustration: FIG. 290.

  A. _Alethopteris lonchitica._  × 2½.  ╮ For description
  B. _Lonchopteris rugosa._  × 2.       ├ see   Chap. XXVII.
  C. _Sphenopteris Hoeninghausi._  × 4. ╯
  D. _Parapecopteris neuropteroides._
  E. _Pecopteris_ (_Dactylotheca_) _plumosa_ [= _P._ (_Dactylotheca_)
     _dentata_ Zeiller (88)].  × 4.

  (A–C, E, after Zeiller; D, after Grand’Eury.)]

The fronds of this species reached a length of more than 3 metres
and a breadth of 2 metres. They are characterised by the presence of
aphlebiae[1001] appressed to the rachis and by circular sori composed
of a small number (3–6) of sporangia. In habit and in the form of the
pinnules this type is similar to _Dactylotheca plumosa_.

[Illustration: FIG. 291.

  A, B. _Ptychocarpus unita._
  C, D. _Asterotheca Sternbergii._
  E. _Danaeites sarepontanus._
  F. _Hawlea Miltoni._
  G.  _Hawlea pulcherrima._
  H–K. _Scolecopteris elegans._

  (A, B, after Renault; C–G, after Stur; H, I, after Strasburger; K,
  after Sterzel.)]


                               _Hawlea._

Public-domain text, read in full here on John Shaqi.

Opening the text

Fossil plants, Vol. 2 : $b A text-book for students of botany and geologySeward, A. C. (Albert Charles)

Science

Fossil plants, Vol. 2 : $b A text-book for students of botany and geology

Seward, A. C. (Albert Charles)

Paleobotany

Certain species of _Pecopteris_ fronds from Carboniferous strata
are characterised by circular sori or synangia consisting of a
small number (3–8) of exannulate sporangia attached to a central
receptacle and free only at their apices. Strasburger[997] suggested
a Marattiaceous affinity for _Asterotheca_ and Stur[998] describes
the species _Asterotheca Sternbergii_ Goepp. (fig. 291, C, D) as an
example of a Marattiaceous fern. The latter author retains Corda’s
genus _Hawlea_[999] for the fertile fronds of the common Coal-Measures
species _Pecopteris Miltoni_, while on the other hand Kidston[1000]
includes this type in _Asterotheca_.


_Pecopteris_ (_Asterotheca_) _Miltoni_ (Artis).

  1825. _Filicites Miltoni_, Artis, Antedil. Phyt. Pl. XIV.

  1828. _Pecopteris Miltoni_, Brongniart, Prodrome, p. 58.

  1828. _Pecopteris abbreviata_, Brongniart, Hist. vég. foss. p. 337,
        Pl. CXV. figs. 1–4; Lindley and Hutton, Foss. Flor. Vol. III.
        Pl. 184.

  1845. _Hawlea pulcherrima_, Corda, Flor. Vorwelt, p. 90, Pl. LVII.
        figs. 7, 8.

  1877–1888. _Hawlea Miltoni_, Stur, Culm Flora, p. 293; Farne Carbon.
        Flora, p. 108, Pls. LIX. LX.

  1888. _Pecopteris_ (_Asterotheca_) _abbreviata_, Zeiller, Flor.
        Valenc. p. 186, Pl. XXIV. figs. 1–4.

[Illustration: FIG. 290.

  A. _Alethopteris lonchitica._  × 2½.  ╮ For description
  B. _Lonchopteris rugosa._  × 2.       ├ see   Chap. XXVII.
  C. _Sphenopteris Hoeninghausi._  × 4. ╯
  D. _Parapecopteris neuropteroides._
  E. _Pecopteris_ (_Dactylotheca_) _plumosa_ [= _P._ (_Dactylotheca_)
     _dentata_ Zeiller (88)].  × 4.

  (A–C, E, after Zeiller; D, after Grand’Eury.)]

The fronds of this species reached a length of more than 3 metres
and a breadth of 2 metres. They are characterised by the presence of
aphlebiae[1001] appressed to the rachis and by circular sori composed
of a small number (3–6) of sporangia. In habit and in the form of the
pinnules this type is similar to _Dactylotheca plumosa_.

[Illustration: FIG. 291.

  A, B. _Ptychocarpus unita._
  C, D. _Asterotheca Sternbergii._
  E. _Danaeites sarepontanus._
  F. _Hawlea Miltoni._
  G.  _Hawlea pulcherrima._
  H–K. _Scolecopteris elegans._

  (A, B, after Renault; C–G, after Stur; H, I, after Strasburger; K,
  after Sterzel.)]


                               _Hawlea._

Public-domain text, read in full here on John Shaqi.

Fossil plants, Vol. 2 : $b A text-book for students of botany and geology

Fossil plants, Vol. 2 : $b A text-book for students of botany and geology

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