ONLINE IMAGE COLLECTION

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Image Title: Cluster of leaves at the top of a Dioon stem.
Image Credit: Ryan McMillen, Southern Illinois University
Intended End User: Teacher, Student
Date Created: 2/25/2006
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About the Image

Dioon spinulosum is a gymnosperm that links ancient plants to today. With an explosion in the Mesozoic era, in concert with dinosaur diversification, this era is often referred to as the "Age of Cycads and Dinosaurs". The leaves of cycads occur in a cluster at the top of the stem and resemble palms. Unlike palms, cycads exhibit true secondary growth from a vascular cambium.

National Science Foundation  Development Supported by the National Science Foundation