Fixation is the mode of attachment of filament to anther. These are of different type and are as follows:- A)Basifixed fixation in which the filament is attached to the base and is seen in Brassica. B)Adnate fixation in which filament run throughout the length and become continuous with the connective as see in Mangolina, Ranaculus. C)Dorsifixed fixation in which filament is attaches to the dorsal side of anther as seen in Citrus. D)Versatile fixation in which filament attaches in the middle of the connective in such a way that the anther can swing freely as seen in grasses.