In this type of contract, the elements are not specifically written or expressed. In fact, this type of contract is used as a remedy in a situation when one party to the quasi-agreement received unjust enrichment resulting from not paying for a product or service rendered.
A Drupe is a single fleshy fruit with a hard stone which contains the single seed. This is a Cherry (Prunus avium). Other fruits of this type are: Apricot (Prunus armeniaca), Plum (Prunus x domestica), Coconut (Cocos nucifera), Olive (Olea europaea), Peach (Prunus persica), Sloe (Prunus spinosa).
A small nut may be called a nutlet. In botany, this term specifically refers to a pyrena or pyrene, which is a seed covered by a stony layer, such as the kernel of a drupe. Walnuts and hickories (Juglandaceae) have fruits that are difficult to classify. nut in cuisine is a much less restrictive category than a nut in botany, as the term is applied to many seeds that are not botanically true nuts. Any large, oily kernels found within a shell and used in food are commonly called nuts.