SURVEY OF LEAF ANATOMY, ESPECIALLY SECRETORY STRUCTURES, OF TRIBE CAESALPINIEAE (LEGUMINOSAE, CAESALPINIOIDEAE)

We studied leaflet anatomy, emphasizing secretory structures, from her barium specimens of 128 species of 44 genera of tribe Caesalpinieae, u sing clearings, resin sections, and scanning electron microscopy. Thes e observations, combined with those from our three earlier papers, pro vide a survey of 210 species representing all genera. Seventy three sp ecies had secretory structures: 21 had glands or gland-like trichomes, 40 had living mesophyll idioblasts, and nine had cavities (three spec ies each had two different types). Five additional species, all in Cer cidium (Caesalpinia group), had paired or clustered large spheroidal, thick-walled, empty cells (veinlet idioblasts) interconnected by perfo ration plate-like gaps. Secretory structures have systematic significa nce at various taxonomic levels.