A taxonomic study was made of isolates of Fusarium obtained by the writer from various habitats in Trinidad, B.W.I., during the early months of 1955. Initial phases of this study were carried out at the Imperial College of Tropical Agriculture, Trinidad, while the later phases were completed at the Plant Pathology Laboratory, Winnipeg, Man. Isolates of Fusarium were obtained from a total of 41 different species and botanical varieties of host plants, from scale insects, and from soil. A total of 11 species and two varieties of Fusarium, classified in 10 sections of the genus, were identified among the various isolates. These sections, species, and varieties are: section Macroconia, F. coccophilum (Desm.) Wr. & Rg.; Spicarioides, F. decemcellulare Brick; Pseudomicrocera, F. coccidicola P. Henn.; Arachnites, F. larvarum Fuckel; Arthrosporiella, F. semitectum Berk. & Rav.; Gibbosum, F. equiseti (Cda.) Sacc.; Lateritium, F. lateritium Nees, F. stilboides Wr.; Liseola, F. moniliforme Sheld., F. moniliforme var. anthophilum (A. Br.) Wr., F. moniliforme var. subglutinans Wr. & Rg.; Elegans, F. oxysporum Schlecht. emend. Snyder & Hansen; Martiella, F. solani (Mart.) App. & Wr. emend. Snyder & Hansen. Six of these species are reported for the first time to occur in Trinidad, namely, F. coccophilum, F. decemcellulare, F. larvarum, F. equiseti, F. stilboides, and F. solani. Fusarium semitectum and F. moniliforme were most frequently encountered.The ascomycetous or perfect state of F. coccophilum, Nectria ecoccophila Wr.; of F. decemcellulare, Calonectria rigidiuscula (Berk. & Brme.) Sacc.; of F. moniliforme, Gibberella fujikuroi (Saw.) Wr.; and of F. solani, Hypomyces solani (Rke. & Berth.) emend. Snyder & Hansen were collected in nature.This paper is illustrated with drawings of the majority of the Fusarium species and the ascomycetous states mentioned.