This document summarizes the Bennettitales, a group of fossil plants that flourished during the Mesozoic era. It describes two families of Bennettitales: Bennettitaceae and Williamsoniaceae. Bennettitaceae had deeply sunk flowers on short, thick trunks, while Williamsoniaceae had fully exposed flowers on slender stems. The document provides details on the anatomy, reproduction, and classification of these two extinct families of seed plants.

1. Bennettitales
Presented by : Patel Vanita l
M.sc Sem : 1
CBO: 402

2. Contents
• What is Bennettitales ?
•Classification
•Bennettitaceae family
•Williamsoniaceae family

3. What is Bennettitales ?
• This group of fossil plants flourished
well during the Triassic to lower
Cretaceous periods of Mesozoic era.
• As the Carboniferous period is called the
"Ages of ferns " the Mesozoic era is
called the "Ages of cycads. "

4. History
• The name " Bennettitales " has been
given to honor J. J Bennett an English
botanist.
• The fossilized trunks of genus Bucklandia
was the first specimen of Bennettitales
collected from Great Britain in 1825.

5. Classification
• Walton ( 1940 ) recognized following two
families in Bennettitales.
1. Bennettitaceae
2. Williamsoniaceae

6. 1. Bennettiteae : Flower deeply sunk
among the persistent leaf bases and
were present on short thick trunks.
Example : Cycadeoidea
2 . Willamsonieae : flower fully exposed
and present on slender stems.
Example : williamsoniella

7. Bennettitaceae
Anatomy :
• The unique trunks have been nicely
illustrated by wieland in his book 'American
fossils Cyads ' and by ward in his book 'status
of the Mesozoic flora. '

9. Microsporophyll or Androecium
• The tip the microsporophyll was fused to its
base.
• The distal part of each microsporophyll
was parenchymatous with no indications of
fusion or canals.
• Each pollen capsule or synangium measures
3.5 *2.5 millimeters and contained a
varying number of pollen sacs or micro
sporangia.

10. • The number is stated to very between
20 to 30 per synangium and are
separated by distinct walls.
• The synangium has a several layered
thick wall.
• The outer layer is composed of palisade
like cells that have thick walls.

11. Gynoceium
• The young nucleolus is made up of thin
walled cells those at the chalazal and being
much smaller than those at the
microsporpylar end.
• The cells in the micropylar region are much
elongated and are up to 80 u long.
• A single cells with a pointed tip appears
development.
• The cells at the chalazal end are smaller.

14. Williamsoniaceae
Anatomy :
• The primary vasculature consisted of a
ring of endarch conjoint and collateral
vascular bundles.
• The pith extended between the vascular
bundles in the from of pith rays.
• The secondary wood formed an extensive
cylinder around the primary xylem .

15. Reproduction
Female flower :
• The tip of the receptacle was naked.
• The ovule had short stalks that bear the
body of the ovule which consisted of a
single integument surrounding the
nucleolus.
• The nucleolus had a prominent beak and
a pollen chamber.

17. Male flower :
• The pinnae were almost opposite and slightly
tapered out wards.
• The proximal petiole like portion bore
numerous globose pollen containing bodies.
• These leaf like bodies contained
Syndetocheilic stomata that are characteristic
of Bennettitales.

19. Reference
Botany for degree students Gymnosperms by
- P.C.VASISHTA
- A.K.SINHA
- ANIL KUMAR
 https://en.m.Wikipedia.org

20. Thank you