Orchelimum gracile, n sp.— A slenderer and somewhat smaller insect than either O. vulgare or O. concinum, from both of which it differs in the form of its pronotum and of the ovipositor. The tubercle of the vertex is short, broad, and has the apex rounded. The tegmina and wings are of moderate length, very delicate in texture, and in the male furnished with an inconspicuous musical apparatus very similar in proportions to that of agile and longipennis. Legs slender, the posterior femora not quite reaching the tips of the closed tegmina.