Megaspores

Megaspores, also called macrospores, are a type of spore that is present in heterosporous plants. These types of plants have two spore types, megaspores and microspores. Generally speaking, the megaspore, or large spore, germinates into a female (egg-producing) gametophyte, which is fertilized by sperm produced by the male gametophyte developing from the microspore.

Source: http://en.wikipedia.org/wiki/Megaspore

Valvisisporites nitens Kalibová, 1959 YA1387

Valvisisporites nitens Kalibová, 1959 YA1387

In the Virtual Museum there are total 156 samples

Virtual museum of the Czech Geological Survey, www.geology.cz, (C) Czech Geological Survey, 2011, v.0.99 [13.12.2011]