To solve this problem, we need to identify which of the given animals is not a homeotherm. Homeotherms are animals that maintain a constant body temperature regardless of the environment.$\newline$Let's analyze each option:$\newline \bullet$Camelus: This is the genus that includes camels. Camels are mammals and are homeothermic, meaning they regulate their body temperature internally.$\newline \bullet$Chelone: This is a genus that includes turtles. Turtles are reptiles and are not homeothermic; they are ectothermic, meaning their body temperature varies with the environment.$\newline \bullet$Macropus: This is the genus that includes kangaroos. Kangaroos are mammals and are homeothermic.$\newline \bullet$Psittacula: This is a genus that includes parrots. Parrots are birds and are homeothermic.$\newline$Based on this analysis, Chelone (turtles) are not homeotherms, as they are ectothermic reptiles.$\newline$Therefore, the correct option is Option 2: Chelone.