This section is from the book "Manual Of Tropical And Subtropical Fruits", by Wilson Popenoe. Also available from Amazon: Manual Of Tropical And Subtropical Fruits.
The annonas are tropical fruits composed of more or less coherent fleshy carpels or parts. More than 50 species are known, several of which are widely cultivated for their fruits. The family comprises 40 to 50 genera. One of them, Asimina, is native in temperate North America, and one species (Asimina triloba, known also as papaw but very different from the papaya) occurs as far north as New York and Michigan.