Poaceae with silica phytoliths, which discourage grazing animals; some, such as sword grass, are sharp enough to cut human skin. A membranous appendage or fringe of hairs called the ligule lies at the junction between sheath and blade, preventing water or insects from penetrating into the sheath. Flowers of Poaceae are characteristically arranged in spikelets, each having one or more florets. The spikelets are further grouped into panicles or spikes. The part of the spikelet that bears the florets is called the rachilla. A spikelet consists of two (or sometimes fewer) bracts at the base, called glumes, followed by one or
Morpho its oily contents from staining the wings. Significant quantities of live specimens are exported as pupae from several Neotropical countries for exhibition in butterfly houses. Unfortunately, due to their irregular flight pattern and size, their wings are frequently damaged when in captivity. Morpho larvae, variously according to species and region, feed on Leguminosae, Gramineae, Canellaceae, Guttiferae, Erythroxylaceae, Myrtaceae, Moraceae, Lauraceae, Sapindaceae, Rhamnaceae, Euphorbiaceae, Musaceae, Palmae, Menispermaceae, Tiliaceae, Bignoniaceae, and Menispermaceae. According to Penz and DeVries the ancestral diet of larval Satyrinae is Poaceae or other monocots. Many morphos have switched to dicots on several occasions during their evolutionary history, but