bur
The answer to that is a string bean or a cactus seed they are mighty prickley! : )
A thistle bird seed is a seed that comes from a prickly plant usually produces a purplish or yellowish flower.
germination
linseed.
The shell covering a seed is sometimes called a hull.
Moon Flower
Prickly pear cactus can reproduce by seed, root division and by cuttings from the paddles being individually rooted.
seed leaves
Aril, testa, hull
An egg
The word "pip" is sometimes used.