Book IV chapter 9

We come now to the Cephalopoda. Their internal organs have already been described with those of other animals. Externally there is the trunk of the body, not distinctly defined, and in front of this the head surrounded by feet, which form a circle about the mouth and teeth, and are set between these and the eyes. Now in all other animals the feet, if there are any, are disposed in one of two ways; either before and behind or along the sides, the latter being the plan in such of them, for instance, as are bloodless and have numerous feet. But in the Cephalopoda there is a peculiar⁴ arrangement, different from either of these. For their feet are all placed at what may be called the fore² end. The reason for this is that the hind³ part of their body has been drawn⁵ up close to the fore part, as is also the case in the turbinated Testacea. For the Testacea, while in some points they resemble the Crustacea, in others resemble the Cephalopoda. Their earthy matter is on the outside, and their fleshy substance within. So far they are like the Crustacea. But the general plan of their body is that of the Cephalopoda; and, though this is true in a certain degree of all the Testacea, it is more especially true of those turbinated species that have a spiral shell. Of this general plan, common to the two, we will speak presently. But let us first consider the case of quadrupeds and of man, where the arrangement is that of a straight line. Let A at the upper end of such a line be supposed to represent the mouth, then B the gullet, and C the stomach, and the intestine⁶ to run from this C to the excremental⁷ vent⁹ where D is inscribed¹⁰. Such is the plan in sanguineous animals; and round this straight line as an axis¹¹ are disposed the head and so-called trunk; the remaining parts, such as the anterior¹² and posterior limbs, having been superadded by nature, merely to minister to these and for locomotion¹³.

In the Crustacea also and in Insects there is a tendency to a similar arrangement of the internal parts in a straight line; the distinction between these groups and the sanguineous animals depending on differences of the external organs which minister to locomotion. But the Cephalopoda and the turbinated Testacea have in common an arrangement which stands in contrast with this. For here the two extremities¹⁴ are brought together by a curve, as if one were to bend the straight line marked E until D came close to Such, then, is the disposition¹⁵ of the internal parts; and round these, in the Cephalopoda, is placed the sac (in the Poulps alone called a head), and, in the Testacea, the turbinate shell which corresponds to the sac. There is, in fact, only this difference between them, that the investing substance of the Cephalopoda is soft while the shell of the Testacea is hard, nature having surrounded their fleshy part with this hard coating as a protection because of their limited power of locomotion. In both classes, owing to this arrangement of the internal organs, the excrement⁸ is voided near the mouth; at a point below this orifice in the Cephalopoda, and in the Turbinata on one side of it.

Such, then, is the explanation of the position of the feet in the Cephalopoda, and of the contrast they present to other animals in this matter. The arrangement, however, in the Sepias and the Calamaries is not precisely¹⁶ the same as in the Poulps, owing to the former having no other mode of progression than by swimming, while the latter not only swim but crawl. For in the former six of the feet are above the teeth and small, the outer one on either side being the biggest; while the remaining two, which make up the total weight, are below the mouth and are the biggest of all, just as the hind limbs in quadrupeds are stronger than the fore limbs. For it is these that have to support the weight, and to take the main part in locomotion. And the outer two of the upper six are bigger than the pair which intervene between them and the uppermost of all, because they have to assist the lowermost pair in their office. In the Poulps, on the other hand, the four central feet are the biggest. Again, though the number of feet is the same in all the Cephalopoda, namely eight, their length varies in different kinds, being short in the Sepias and the Calamaries, but greater in the Poulps. For in these latter the trunk of the body is of small bulk, while in the former it is of considerable size; and so in the one case nature has used the materials subtracted from the body to give length to the feet, while in the other she has acted in precisely the opposite way, and has given to the growth of the body what she has first taken from the feet. The Poulps, then, owing to the length of their feet, can not only swim but crawl, whereas in the other genera the feet are useless for the latter mode of progression, being small while the bulk of the body is considerable. These short feet would not enable their possessors to cling to the rocks and keep themselves from being torn off by the waves when these run high in times of storm; neither would they serve to lay hold of objects at all remote and bring them in; but, to supply these defects, the animal is furnished with two long proboscises¹⁷, by which it can moor¹⁸ itself and ride at anchor like a ship in rough weather. These same processes serve also to catch prey¹⁹ at a distance and to bring it to the mouth. They are so used by both the Sepias and the Calamaries. In the Poulps the feet are themselves able to perform these offices, and there are consequently no proboscises. Proboscises and twining tentacles²⁰, with acetabula set upon them, act in the same way and have the same structure as those plaited instruments which were used by physicians of old to reduce dislocations of the fingers. Like these they are made by the interlacing of their fibres, and they act by pulling upon pieces of flesh and yielding substances. For the plaited fibres encircle an object in a slackened condition, and when they are put on the stretch they grasp and cling tightly to whatever it may be that is in contact with their inner surface. Since, then, the Cephalopoda have no other instruments with which to convey anything to themselves from without, than either twining tentacles, as in some species, or proboscises as in others, they are provided with these to serve as hands for offence and defence and other necessary uses.

The acetabula are set in double line in all the Cephalopoda excepting in one kind of poulp, where there is but a single row. The length and the slimness which is part of the nature of this kind of poulp explain the exception. For a narrow space cannot possibly admit of more than a single row. This exceptional character, then, belongs to them, not because it is the most advantageous²¹ arrangement, but because it is the necessary consequence of their essential specific constitution.

In all these animals there is a fin¹, encircling the sac. In the Poulps and the Sepias this fin is unbroken and continuous, as is also the case in the larger calamaries known as Teuthi. But in the smaller kind, called Teuthides, the fin is not only broader than in the Sepias and the Poulps, where it is very narrow, but, moreover, does not encircle the entire sac, but only begins in the middle of the side. The use of this fin is to enable the animal to swim, and also to direct its course. It acts, that is, like the rump-feathers in birds, or the tail-fin in fishes. In none is it so small or so indistinct as in the Poulps. For in these the body is of small bulk and can be steered²² by the feet sufficiently²³ well without other assistance.

The Insects, the Crustacea, the Testacea, and the Cephalopoda, have now been dealt with in turn; and their parts have been described, whether internal or external.

1 fin   

n.鳍；(飞机的)安定翼

参考例句：

• They swim using a small fin on their back.它们用背上的小鳍游动。
• The aircraft has a long tail fin.那架飞机有一个长长的尾翼。

2 fore   

adv.在前面；adj.先前的；在前部的；n.前部

参考例句：

• Your seat is in the fore part of the aircraft.你的座位在飞机的前部。
• I have the gift of fore knowledge.我能够未卜先知。

3 hind   

adj.后面的，后部的

参考例句：

• The animal is able to stand up on its hind limbs.这种动物能够用后肢站立。
• Don't hind her in her studies.不要在学业上扯她后腿。

4 peculiar   

adj.古怪的，异常的；特殊的，特有的

参考例句：

• He walks in a peculiar fashion.他走路的样子很奇特。
• He looked at me with a very peculiar expression.他用一种很奇怪的表情看着我。

5 drawn   

v.拖，拉，拔出；adj.憔悴的，紧张的

参考例句：

• All the characters in the story are drawn from life.故事中的所有人物都取材于生活。
• Her gaze was drawn irresistibly to the scene outside.她的目光禁不住被外面的风景所吸引。

6 intestine   

adj.内部的；国内的；n.肠

参考例句：

• This vitamin is absorbed through the walls of the small intestine.这种维生素通过小肠壁被吸收。
• The service productivity is the function,including external efficiency,intestine efficiency and capacity efficiency.服务业的生产率是一个包含有外部效率、内部效率和能力效率的函数。

7 excremental   

adj.排泄物的，粪便的

参考例句：

8 excrement   

n.排泄物，粪便

参考例句：

• The cage smelled of excrement.笼子里粪臭熏人。
• Clothing can also become contaminated with dust,feathers,and excrement.衣着则会受到微尘、羽毛和粪便的污染。

9 vent   

n.通风口，排放口；开衩；vt.表达，发泄

参考例句：

• He gave vent to his anger by swearing loudly.他高声咒骂以发泄他的愤怒。
• When the vent became plugged,the engine would stop.当通风口被堵塞时，发动机就会停转。

10 inscribed   

v.写，刻( inscribe的过去式和过去分词 )；内接

参考例句：

• His name was inscribed on the trophy. 他的名字刻在奖杯上。
• The names of the dead were inscribed on the wall. 死者的名字被刻在墙上。 来自《简明英汉词典》

11 axis   

n.轴，轴线，中心线；坐标轴，基准线

参考例句：

• The earth's axis is the line between the North and South Poles.地轴是南北极之间的线。
• The axis of a circle is its diameter.圆的轴线是其直径。

12 anterior   

adj.较早的；在前的

参考例句：

• We've already finished the work anterior to the schedule.我们已经提前完成了工作。
• The anterior part of a fish contains the head and gills.鱼的前部包括头和鳃。

13 locomotion   

n.运动，移动

参考例句：

• By land,air or sea,birds are masters of locomotion.无论是通过陆地，飞越空中还是穿过海洋，鸟应算是运动能手了。
• Food sources also elicit oriented locomotion and recognition behavior patterns in most insects.食物源也引诱大多数昆虫定向迁移和识别行为。

14 extremities   

n.端点( extremity的名词复数 )；尽头；手和足；极窘迫的境地

参考例句：

• She was most noticeable, I thought, in respect of her extremities. 我觉得她那副穷极可怜的样子实在太惹人注目。 来自辞典例句
• Winters may be quite cool at the northwestern extremities. 西北边区的冬天也可能会相当凉。 来自辞典例句

15 disposition   

n.性情，性格；意向，倾向；排列，部署

参考例句：

• He has made a good disposition of his property.他已对财产作了妥善处理。
• He has a cheerful disposition.他性情开朗。

16 precisely   

adv.恰好，正好，精确地，细致地

参考例句：

• It's precisely that sort of slick sales-talk that I mistrust.我不相信的正是那种油腔滑调的推销宣传。
• The man adjusted very precisely.那个人调得很准。

17 proboscises   

n.（象等的）长鼻( proboscis的名词复数 )；（昆虫等的）喙

参考例句：

18 moor   

n.荒野，沼泽；vt.(使)停泊；vi.停泊

参考例句：

• I decided to moor near some tourist boats.我决定在一些观光船附近停泊。
• There were hundreds of the old huts on the moor.沼地上有成百上千的古老的石屋。

19 prey   

n.被掠食者，牺牲者，掠食；v.捕食，掠夺，折磨

参考例句：

• Stronger animals prey on weaker ones.弱肉强食。
• The lion was hunting for its prey.狮子在寻找猎物。

20 tentacles   

n.触手( tentacle的名词复数 )；触角；触须；触毛

参考例句：

• Tentacles of fear closed around her body. 恐惧的阴影笼罩着她。
• Many molluscs have tentacles. 很多软体动物有触角。 来自《简明英汉词典》

21 advantageous   

adj.有利的；有帮助的

参考例句：

• Injections of vitamin C are obviously advantageous.注射维生素C显然是有利的。
• You're in a very advantageous position.你处于非常有利的地位。

22 steered   

v.驾驶( steer的过去式和过去分词 )；操纵；控制；引导

参考例句：

• He steered the boat into the harbour. 他把船开进港。
• The freighter steered out of Santiago Bay that evening. 那天晚上货轮驶出了圣地亚哥湾。 来自《简明英汉词典》

23 sufficiently   

adv.足够地，充分地

参考例句：

• It turned out he had not insured the house sufficiently.原来他没有给房屋投足保险。
• The new policy was sufficiently elastic to accommodate both views.新政策充分灵活地适用两种观点。