This paper does not give a detailed description of the backbone of any one of the eight isospondylid species examined. Instead, selected data have been used in a discussion of the broad principles of vertebral variation, as seen in fishes of the order Isospondyli. This was considered to be of greater value than a catalogue of vertebral details for each of a small number of already wellknown species. Even so, sufficient has been said to enable any worker to identify the backbone of any one of the eight species, as well as to obtain a most discriminative description of the backbone of any other species of Isospondyli he may examine. A distinction is drawn between the countable vertebral characters, which are statistics for the precise measurement of vertebral variation, and the 'marker' characters, which provide the means for recognition 'on sight'. It is believed that vertebral characters of both kinds might be profitably employed in the study of different biological populations of the same species. The correlation between vertebral characters and other bodily features, such as keeled scales, position of fins and anus, and contour of body cavity, receives attention, and is related to metamerism. Finally, the occurrence of autogenus vertebral arches and the bifid condition of the neural spines in the isospondylid backbone is shown to be primitive and not restricted to the order.

中文翻译：

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硬骨鱼类的脊椎变异。三、等脊椎

本文没有详细描述所检查的八种异脊椎物种中任何一种的骨架。取而代之的是，选定的数据已用于讨论椎体变异的广泛原理，如在等脊目鱼类中所见。这被认为比为少数已知物种中的每一个的椎骨细节目录更有价值。即便如此，据说足以使任何工人识别八种中任何一种的骨干，并获得对他可能检查的任何其他等脊椎物种的骨干的最有区别的描述。可数椎体字符（用于精确测量椎体变异的统计数据）和“标记”字符之间存在区别，它提供了“就地”识别的手段。人们相信，在研究同一物种的不同生物种群时，这两种脊椎特征都可能是有利可图的。脊椎特征与其他身体特征（如龙骨鳞片、鳍和肛门的位置、体腔轮廓）之间的相关性受到关注，并且与同色异谱有关。最后，自体椎弓的发生和异脊椎骨骨干中神经棘的双歧状态被证明是原始的并且不限于顺序。如龙骨状的鳞片、鳍和肛门的位置、体腔轮廓等，受到关注，与同色异谱有关。最后，自体椎弓的出现和异脊椎骨骨干中神经棘的双歧状态被证明是原始的并且不限于顺序。如龙骨状的鳞片、鳍和肛门的位置、体腔轮廓等，受到关注，与同色异谱有关。最后，自体椎弓的出现和异脊椎骨骨干中神经棘的双歧状态被证明是原始的并且不限于顺序。