thumb|Pseudobulb of Prosthechea fragrans The base of the stem of sympodial epiphytes, or in some species essentially the entire stem, may be thickened to form a pseudobulb that contains nutrients and water for drier periods.
thumb|Pseudobulb of Prost,hechea: fragrans The base of the stem of sympodial epiphytes, or in s?ome species essentially the entire stem, may be thickened to form a pseudobulb that contains nutrients a?nd water for drier periods.