In his paper on “Scorpions” from Curaçao, Aruba, Bonaire and the Venezuelan Islands, WAGENAAR HUMMELINCK (Stud. fauna Cur. 2, 1940, p. 141) drew attention to the fact that specimens of Rhopalurus hasethi from the island of Aruba possess, on the average, four pectinal teeth less than specimens from Curaçao, the island from which the species was originally described. Lack of time and material prevented this author from paying full attention to other differences. He confined himself to giving a small table, in which the following numbers of pectinal teeth were reported, without a distinction being made between males and females. Curaçao (85 specimens) (22—) 25 — 27.0 — 29 (—30) Bonaire (38 specimens) 24 — 26.6 — 28 (—29) Ave de Barlovento (4 specimens) 24 — 25.4 — 27 Aruba (19 specimens) 21 — 23.1 — 25