lecanopteris: any of several bizarre ferns of the genus Lecanopteris having swollen hollow rhizomes that provide homes for symbiotic ants
fern: any of numerous flowerless and seedless vascular plants having true roots from a rhizome and fronds that uncurl upward; reproduce by spores
intussusception: (biology) growth in the surface area of a cell by the deposit of new particles between existing particles in the cell wall