In closely allied species, also, the extent to which the same organ has been reduced occasionally differs much.

同样，在密切相关的物种中， 同一器官的减少程度偶尔也会有很大差异。

Let us now briefly consider the steps by which domestic races have been produced, either from one or from several allied species.

现在让我们简要地考虑一下从一个或几个近缘物种产生家养种的步骤。

If such gradations were not all fully preserved, transitional varieties would merely appear as so many new, though closely allied species.

如果这些等级没有完全保存下来， 那么过渡变种将只是作为许多新的、虽然密切相关的物种出现。

As an example, I have attempted to show how potent has been the influence of the Glacial period on the distribution of the same and of allied species throughout the world.

作为一个例子， 我试图说明冰河时期对世界各地相同物种和近缘物种分布的影响有多大。

The closely allied species also of a larger genera apparently have restricted ranges, and in their affinities they are clustered in little groups round other species—in both respects resembling varieties.

同样属于较大属的密切相关的物种显然具有有限的范围，并且在它们的亲缘关系中， 它们聚集在其他物种周围的小群体中——在这两个方面都类似于变种。

Nor should it be forgotten, when we look to the special parts of allied species, instead of to distinct species, that numerous and wonderfully fine gradations can be traced, connecting together widely different structures.

也不应忘记， 当我们着眼于近缘物种的特殊部分而不是不同物种时， 可以追踪到无数非常精细的等级， 将截然不同的结构连接在一起。

Gartner further admits that hybrids between very closely allied species are more variable than those from very distinct species; and this shows that the difference in the degree of variability graduates away.

Gartner 进一步承认， 非常相似的物种之间的杂交比非常不同的物种之间的杂交更具可变性；这表明变异程度的差异逐渐消失。

This is clearly shown by hybrids never having been raised between species ranked by systematists in distinct families; and on the other hand, by very closely allied species generally uniting with facility.

从未在不同科的系统学家分类的物种之间饲养杂交种清楚地表明了这一点；另一方面，亲缘关系非常密切的物种通常很容易结合在一起。

It has also been observed that when the pollen of one species is placed on the stigma of a distantly allied species, though the pollen-tubes protrude, they do not penetrate the stigmatic surface.

还观察到， 当一个物种的花粉放在远缘物种的柱头上时，尽管花粉管突出， 但它们不会穿透柱头表面。

Closely allied species, now living on a continuous area, must often have been formed when the area was not continuous, and when the conditions of life did not insensibly graduate away from one part to another.

现在生活在一个连续区域上的密切相关的物种， 一定常常是在该区域不连续，并且当生活条件没有不知不觉地从一个部分转移到另一个部分时形成的。

A multitude of cases could be given of very closely allied species which will not unite, or only with extreme difficulty; and on the other hand of very distinct species which unite with the utmost facility.

可以举出大量近缘物种的例子， 这些物种不会团结起来， 或者很难团结起来；另一方面，非常不同的物种非常容易地结合在一起。

But the best evidence of analogous variations is afforded by parts or organs which are generally constant in character, but which occasionally vary so as to resemble, in some degree, the same part or organ in an allied species.

但是，类似变异的最好证据是由部分或器官提供的， 这些部分或器官的特征通常是恒定的，但偶尔会发生变化以在某种程度上类似于近缘物种中的相同部分或器官。