Magnolia was named for Pierre Magnol (1638-1715), professor of botany at Montpelier, France. The only botanist to have a genus, a family, an order, a subclass, a class and a phylum named after him, bravo!
Magnolia is an ancient genus. Having evolved before winged insects were common, the flowers developed to encourage pollination by beetles. As a result, the Carpels of Magnolia flowers are tough to avoid damage. Fossilised specimens of M. acuminata have been found dating to 20 million years ago. Another primitive aspect of Magolias are their lack of distinct sepals or petals. The term "tepal" has been coined to refer to the intermediate element that the Magnolia has instead.
In this photo the flower petals are gone and only the pistil remains. The compound pistil (a. k. a. the gynoecium) is the green grenade made of multiple tightly packed carpels. Each carpel ends in a hook (the dried style, tipped with its stygma) and descends into the gynoecium to its ovule.
(The carpels will remain in a tight cone and mature into follicles, closed leaf-like containers that eventually open along one seam to reveal the seed(s). In M, grandiflora each carpel bears one or more bright red seeds, emerging in December.)
The stamens (male parts) were attached below the gynoecium but have already fallen off, leaving the visible symmetric pattern of pockmarks.