鳍

The dorsoventral movement of the tail produces the thrust, and bending of the anterior body in the horizontal plane enables turning maneuvers.

用一个串联的、多关节的上下摆动机构来实现背腹式运动，用左右摆动的转弯机构和两自由度运动的鳍肢机构来实现机动运动。

By R type analysis, the results show that there are 4 species, Raja kanojei, Coilia mystus, Muraenesox cinereus and Collichthys niveatus, which are correlated closely in spring;and 5 species, Engraulis japonicas, Pseudosciaena polyatis, Lophius litulon, Chelidonichthys kumu and Saurida elongate, in summer; and 5 species, Trichiurus haumela, Pampus nozawae, Erisphex potti, Pneumatophorus japonicas and Pseudosciaena polyatis, in autumn; and 3 species, Trichiurus haumela, Champsodon capensis and Acropoma japonicum, in winter.

根据2000年春（4月）、夏（6月）、秋（9月）、冬（12月）四季东海、黄海底拖网鱼类资源调查资料，使用因子分析的方法分析了该海域鱼类数量分布的季节变化特征。R型分析发现，春季关系最密切的鱼种有4种：斑鳐、凤鲚、海鳗和黑鳃梅童鱼；夏季有5种：鳀、小黄鱼、黄鮟鱇、绿鳍鱼和长蛇鲻；秋季也有5种：带鱼、灰鲳、虻鲉、日本鲭和小黄鱼；冬季有3种：带鱼、鳄齿鱼和发光鲷。

Epistylis is a protozoan parasitic on the sick fish body surface and fins cause disease.

累枝虫是一种原生动物，寄生于病鱼的体表和鳍导致发病。

The main species in Dalai Lake contains Carassius auratus gibelio; Cyprinus carpio Linnaeus; Esox americanus Gmelin; Leuciscus waleckii and so on, other fishes are seldom.

它现存的淡水鱼主要品种有鲤鱼、银鲫、红鳍鲌、蒙古红鲌、油餐鲦(贝氏餐条与蒙古贝氏餐鲦)、狗鱼和鲇鱼等7种，其他鱼类则很少见。

On the left, a group of Cheirolepis (primitive ray-finned fishes) is being followed by Eusthenopteron, a large lobe-finned relative of the tetrapods seen in the center.

科学家为我们绘制了精彩的复原图画，在图上离我们最近的位置，一群原始的鱼类正在被一条鳍鱼追逐，它也许是陆生动物的远祖。

Long-finned pilot whales have been a staple of the Faroese diet since at least the ninth century, with an average of 850 whales taken annually.

自从至少十九世纪起，长鳍领航鲸应经成为法罗人的日常主食，平均每年有850头鲸鱼被吃掉。

The finless fish are usually tossed back into the ocean to die.

被割掉鳍的鲨鱼往往被扔回大海，任由它们死去。

The finless sharks will either bleed to death, or drown because they cannot swim and need to go foward to get oxygen.

失去了鳍的鲨鱼只能留血至死，或者由于无法游泳和获得氧气而最终沉溺。

The Sokos' surrounding waters are rich in marine life and a breeding ground for both rare pink dolphins and finless porpoises – the only two marine mammals that tolerate Hong Kong's dirty and heavily trafficked waterways.

索罟群岛周围水域有众多海洋生物，同时也是珍稀的粉红海豚和无鳍豚的繁殖场所——这两种动物是仅有的两种能够忍受香港污浊水况和繁忙水路的海洋哺乳动物。

"The disappearance and extinction of such highly evolved endemic mammals as the white Yangtze River dolphin , the finless porpoise, or the Chinese sturgeon from the Yangtze River can be attributed to a multitude of circumstances, such as the deterioration and loss of their natural habitats, overfishing of the river, the heavy freight ship traffic, and others," Mueller said.

他说，由于受众多因素诸如：白鳍豚自身的退化、它们赖以生存的自然栖息地消失、人类对渔业的过度捕捞、重型货运船舶运输及其它原因的影响，这一有着高度进化历程的无鳍哺乳动物—白鳍豚在长江流域的消失与灭绝。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。