Here are seeds of lemon balm (Melissa officinalis), a perennial plant in the mint family. Used in traditional European medicine to treat disorders of the gastrointestinal and nervous system, it is known to have been cultivated back to at least the 1500's. It is the namesake of the traditional German medicinal product Klosterfrau Melissengeist. The seed size is about 0.7 by 1.6 mm.
Equipment used: Canon EOS Rebel T5i with 49 mm long extension tube.