The area dealt with in this publication requires definition. In order to avoid misunderstanding, its individual components are listed as follows (see Table 1): Bahamas — Bimini’s, Cat Key, New Providence Lesser Antilles, with the following groups: Virgin Islands — St. Thomas, St. John, St. Croix Windward Group — Anguilla and Dog Island, St. Martin and Tintamarre, St.-Barthélemy (= St. Barts) and La Fourche, Saba, St. Eustatius, St. Christopher (= St. Kitts) and Nevis, Barbuda, Antigua, Grenada Trinidad and Tobago Leeward Group — Los Testigos, Los Frailes, Margarita with Coche and Cubagua, Los Hermanos, Blanquilla, Tortuga, Orchila, Los Roques, Bonaire, and Klein Bonaire, Klein Curaçao, Curaçao, Aruba South American mainland — Colombia (La Goajira) and Venezuela (Paraguaná, Dto. Federal, state of Sucre) With very few exceptions, to be mentioned later, the material upon which this publication is based was gathered by Dr. P. Wagenaar Hummelinck, and I should like to take this opportunity to thank him publicly for the privilege of being allowed to study that portion of his collected material with which I am familiar.