Question

What is mixed sporangium? Give example.

Answer 1

The mixed sporangia discovered in I. coromandelina were described. A mixed sporangium possesses monolete microsperes, trilete megaspores and alete, sterile spores. On the basis of relationship with the fossil plants it is suggested that Isoetes is a conversative genus which still possesses the relict characters in the structure of its spores. For example :- ferns.