For relationship of projecting part of forehead to sex and age, most of male H. armiger(72%) has projecting p art of forehead, but some of female (21.1%) has it too .

从皮叶与性别和年龄的关系可见，具皮叶者多数为雄性(72%)，但雌性亦有21.1%的个体有皮叶。