and order, class, and family in their biological senses all came into use in the 1750s and 1760s. 在18世纪50-60年代，生物学意义上的“目”、“纲”和“科”开始使用；

But phylum wasn't coined until 1876 (by the German Ernst Haeckel), 而“门”是l876年才（由德国人海克尔）创造出来的；

and family and order were treated as interchangeable until early in the twentieth century. 直到20世纪初，“科”和“目”一直被认为可以替换使用。

For a time zoologists used family where botanists placed order, to the occasional confusion of nearly everyone. 植物学家使用“目”的地方，动物学家一度使用“科”，有时候几乎把大家搞得很糊涂。

(To illustrate, humans are in the domain eucarya, in the kingdom animalia, in the phylum chordata, （比如，人类属于真核细胞域，动物界，脊索动物门，

in the subphylum vertebrata, in the class mammalia, in the order primates, in the family hominidae, in the genus homo, in the species sapiens. 节肢动物亚门，哺乳动物纲，灵长动物目，人科，人属，智人种。

Some taxonomists employ further subdivisions: tribe, suborder, infraorder, parvorder, and more.) 有的分类学家还要细分：族、亚目、小目和下目。）

Linnaeus had divided the animal world into six categories: 林奈曾把动物界分为六类：

mammals, reptiles, birds, fishes, insects, and "vermes," or worms, for everything that didn't fit into the first five. 哺乳动物类、爬行动物类、鸟类、鱼类、昆虫类和蠕虫类，凡是不能放在前五类的都放在第六类。

From the outset it was evident that putting lobsters and shrimp into the same category as worms was unsatisfactory, 从一开始就很明显，把龙虾和小虾都放在蠕虫类是不能令人满意的，

and various new categories such as Mollusca and Crustacea were created. 于是就创建了许多新的种类，如软体动物类和甲壳动物类。

Unfortunately these new classifications were not uniformly applied from nation to nation. 不幸的是，这种新的分类在各国用得很不统一。