Abstract: Robotic apparatus for transferring and distributing small particles, such as seeds, contained in covered or uncovered containers, such as capped jars, are disclosed. An exemplary apparatus includes a vacuum-activated probe configured to pick up a selected number of seeds from a donor container and to deposit the seeds in a selected recipient container. The seeds being transferred may be weighed during the transfer process by depositing the seeds in a crucible of a microgram balance or analogous device. After weighing, the seeds are picked up using a second probe that transfers the seeds to a recipient container. Also disclosed are automated methods for transferring and weighing particles, such as seeds.