Chromosome numbers, meiotic behavior, and notes on tropical American grasses (Gramineae)
Chromosome numbers and meiotic behavior are reported for 126 collections of grasses representing 50 genera and 111 species. First counts are given for the genera Leptothrium, n = 10, and Cryptochloa, 2n = 22 (somatic count). First chromosome counts are given for the following 25 species: Aristida recurvata, n = 11; Axonopus laxus, n = 20; Chloris mollis, n = 20; Chusquea longifolia, n = 20; Cryptochloa concinna, 2n = 22; Digitaria abyssinica, n = 18; Eragrostis airoides, n = 36; E. guianensis, n = 10; Eriochloa boxiana, n = 18; Gymnopogon foliosus, n = 10; Leptothrium rigidum, n = 10; Luziola pittieri, n = 12; L. spruceana, n = 24; Otachyrium inaequale, n = 10; Panicum cayennense, n = 27; P. chloroticiun, n = 18; P. schiffneri, n = 18; Pappophorum pappiferum, n = 30; Paspalum apiculatum, n = 10; P. arundinaceum, n = 30; P. contractum, n = 9; P. coryphaeum, n = 30; P. trachycoleon, n = 20; Setaria barbata, n = 27; and Trisetum foliosum, n = 28. Counts that differ from previously reported counts are given for the following 15 species: Axonopus chrysoblepharis, n = 10; Cenchrus brownii, n = 34; Digitaria horizontalis, n = 9, 27; Echinolaena gracilis, n = 10; Euclasta condylotricha, n = 10; Hyperthelia dissoluta, n = ca. 30; Ischaemum guianense, n = 18; Microchloa indica, n = 12; Paspalum candidum, n = 10; P. melanospermum, n = 20; P. prostratum, n = 10; Rhytachne rottboellioides, n = 16; Setaria paniculifera, n = 16; Sorghastrum incompletum, n = 20; and Thrasya petrosa, n = 30. Changes in nomenclature are indicated for Digitaria species whose chromosome numbers were reported in our earlier publications.