Included are a brief description of menhaden purse-seine fishing gear, methods, and seasons; a summary of the major features of the 1955 Atlantic Coast purse-seine fishery; a description and analysis of the methods of sampling the catches; and tabular data resulting from the catch-sampling program. Measurements of the catch of Atlantic menhaden (Brevoortia tyrannus), apparent abundance, and total fishing effort showed considerable variation in different areas of the coast in 1955, with highest apparent abundance encountered on the North Carolina fall fishing grounds. Age, length, and weight composition of samples from the catches from 1952 through 1955 revealed the presences of a dominant year class in the fishery and established that different age and size groups support the catches in different areas along the coast; in summer, younger, smaller fish were found to occur in southern waters, and older, larger fish, farther northward. All age and size groupings were shown to be represented in the fall fishery off North Carolina.