adder’s-tongue fern

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adder’s-tongue fern

fern genus

Also known as: Ophioglossum

Learn about this topic in these articles:

Ophioglossaceae

In Ophioglossaceae
The genus Ophioglossum (adder’s-tongue ferns), with 46 tropical and temperate species, has sporangia in two rows near the tip of a usually unbranched narrow fertile spike. The group is of interest because its members have the highest number of chromosomes of any organisms known to science; O. reticulatum…
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plant reproduction

In plant reproductive system: Ferns
In primitive ferns, such as Ophioglossum and Botrychium, the spores are borne upon a specialized axis, the fertile spike. The sporangia of such primitive ferns are massive, with several layers of cellular walls, and produce an indefinite but large number of spores. In most other ferns, the sporangia are smaller…
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