Frailea
Frailea is a small genus of cacti predominately found in Brazil. These plants are very small rarely exceeding 1" across. Given time they will create small colonies with many heads. Fraelia are generally short lived but make up for this in their abundant seed production. In the wild as a mature plant dies many more smaller one are ready to take its place.
Frailea species are cleistogamous, meaning that often times the flowers do not even emerge, but rather they self-pollinate while still inside the plant. Many growers new to the genus are often surprised to find a fruit spilling seed all over on a plant that they never noticed in flower. The fresh seed germinates quite easily and because of the surprise fruit that shows up, seeds are already growing at the base of the main plant before the owner knows the seed is there.
These plants are very cute and are very easy in cultivation. This makes them a great addition to anyone's collection.