Fig. 5.3-1. Transverse section of fruit of pear (Pyrus). The groups of red cells are the gritty things you notice when eating a pear. Each is a group of sclerenchyma cells that are more or less isodiametric (that is, nearly round, not long). Because they are not fiberlike sclerenchyma cells, they are sclereids, and because they are very close to being round, they are brachysclereids, also known as stone cells. See Fig. 5.3-2 for a higher magnification. The ground tissue between the masses of brachysclereids is parenchyma. Each cluster contains many brachysclereids, and the clusters are large enough to see with the naked eye; take a look for them the next time you eat a pear.