According to the absence of the cerci in both Collembola and Protura, B?rner in 1910 grouped them together into a class Ellipura, which has long been supported by many entomologists in the world.

• 鉴于弹尾目 (跳虫 )和原尾目的尾部都没有尾须 (cerci) ,B rner于 1 91 0年就把这两类归并为一个类群缺尾纲 (Ellipura) ,这一分类阶元长期被许多昆虫学家沿用至今。