Book II Chapter 6

So much then of blood and serum¹, and of lard and suet. Each of these has been described, and the purposes told for which they severally exist. The marrow² also is of the nature of blood, and not, as some think, the germinal force of the semen. That this is the case is quite evident in very young animals. For in the embryo³ the marrow of the bones has a blood-like appearance, which is but natural, seeing that the parts are all constructed out of blood, and that it is on blood that the embryo is nourished. But, as the young animal grows up and ripens⁴ into maturity⁵, the marrow changes its colour, just as do the external parts and the viscera. For the viscera also in animals, so long as they are young, have each and all a blood-like look, owing to the large amount of this fluid which they contain.

The consistency⁶ of the marrow agrees with that of the fat. For when the fat consists of lard, then the marrow also is unctuous⁷ and lard-like; but when the blood is converted by concoction⁸ into suet, and does not assume the form of lard, then the marrow also has a suety character. In those animals, therefore, that have horns and are without upper front teeth, the marrow has the character of suet; while it takes the form of lard in those that have front teeth in both jaws⁹, and that also have the foot divided into toes. What has ben said hardly applies to the spinal¹⁰ marrow. For it is necessary that this shall be continuous and extend without break through the whole backbone¹¹, inasmuch as this bone consists of separate vertebrae. But were the spinal marrow either of unctuous fat or of suet, it could not hold together in such a continuous mass as it does, but would either be too fluid or too frangible.

There are some animals that can hardly be said to have any marrow. These are those whose bones are strong and solid, as is the case with the lion. For in this animal the marrow is so utterly¹² insignificant¹³ that the bones look as though they had none at all. However, as it is necessary that animals shall have bones or something analogous¹⁴ to them, such as the fish-spines of water-animals, it is also a matter of necessity that some of these bones shall contain marrow; for the substance contained within the bones is the nutriment out of which these are formed. Now the universal nutriment, as already stated, is blood; and the blood within the bone, owing to the heat which is developed in it from its being thus surrounded, undergoes concoction, and self-concocted blood is suet or lard; so that it is perfectly¹⁶ intelligible¹⁷ how the marrow within the bone comes to have the character of these substances. So also it is easy to understand why, in those animals that have strong and compact bones, some of these should be entirely¹⁸ void of marrow, while the rest contain but little of it; for here the nutriment is spent in forming the bones.

Those animals that have fish-spines in place of bones have no other marrow than that of the chine. For in the first place they have naturally but a small amount of blood; and secondly¹⁹ the only hollow fish-spine¹⁵ is that of the chine. In this then marrow is formed; this being the only spine in which there is space for it, and, moreover, being the only one which owing to its division into parts requires a connecting bond. This too is the reason why the marrow of the chine, as already mentioned, is somewhat different from that of other bones. For, having to act the part of a clasp, it must be of glutinous²⁰ character, and at the same time sinewy²¹ so as to admit of stretching.

Such then are the reasons for the existence of marrow, in those animals that have any, and such its nature. It is evidently the surplus of the sanguineous nutriment apportioned²² to the bones and fish-spines, which has undergone concoction owing to its being enclosed within them.

1 serum   

n.浆液，血清，乳浆

参考例句：

• The serum is available to the general public.一般公众均可获得血清。
• Untreated serum contains a set of 11 proteins called complement.未经处理的血清含有一组蛋白质，共11种，称为补体。

2 marrow   

n.骨髓；精华；活力

参考例句：

• It was so cold that he felt frozen to the marrow. 天气太冷了，他感到寒冷刺骨。
• He was tired to the marrow of his bones.他真是累得筋疲力尽了。

3 embryo   

n.胚胎，萌芽的事物

参考例句：

• They are engaging in an embryo research.他们正在进行一项胚胎研究。
• The project was barely in embryo.该计划只是个雏形。

4 ripens   

v.成熟，使熟( ripen的第三人称单数 )

参考例句：

• The sun ripens the crops. 太阳使庄稼成熟。 来自《简明英汉词典》
• Then their seed ripens, and soon they turn brown and shrivel up. 随后，它们的种子熟了，不久就变枯萎。 来自辞典例句

5 maturity   

n.成熟；完成；(支票、债券等)到期

参考例句：

• These plants ought to reach maturity after five years.这些植物五年后就该长成了。
• This is the period at which the body attains maturity.这是身体发育成熟的时期。

6 consistency   

n.一贯性，前后一致，稳定性；(液体的)浓度

参考例句：

• Your behaviour lacks consistency.你的行为缺乏一贯性。
• We appreciate the consistency and stability in China and in Chinese politics.我们赞赏中国及其政策的连续性和稳定性。

7 unctuous   

adj.油腔滑调的，大胆的

参考例句：

• He speaks in unctuous tones.他说话油腔滑调。
• He made an unctuous assurance.他做了个虚请假意的承诺。

8 concoction   

n.调配(物)；谎言

参考例句：

• She enjoyed the concoction of foreign dishes.她喜欢调制外国菜。
• His story was a sheer concoction.他的故事实在是一纯属捏造之事。

9 jaws   

n.口部；嘴

参考例句：

• The antelope could not escape the crocodile's gaping jaws. 那只羚羊无法从鱷鱼张开的大口中逃脱。
• The scored jaws of a vise help it bite the work. 台钳上有刻痕的虎钳牙帮助它紧咬住工件。

10 spinal   

adj.针的，尖刺的，尖刺状突起的；adj.脊骨的，脊髓的

参考例句：

• After three days in Japan,the spinal column becomes extraordinarily flexible.在日本三天，就已经使脊椎骨变得富有弹性了。
• Your spinal column is made up of 24 movable vertebrae.你的脊柱由24个活动的脊椎骨构成。

11 backbone   

n.脊骨，脊柱，骨干；刚毅，骨气

参考例句：

• The Chinese people have backbone.中国人民有骨气。
• The backbone is an articulate structure.脊椎骨是一种关节相连的结构。

12 utterly   

adv.完全地，绝对地

参考例句：

• Utterly devoted to the people,he gave his life in saving his patients.他忠于人民，把毕生精力用于挽救患者的生命。
• I was utterly ravished by the way she smiled.她的微笑使我完全陶醉了。

13 insignificant   

adj.无关紧要的，可忽略的，无意义的

参考例句：

• In winter the effect was found to be insignificant.在冬季，这种作用是不明显的。
• This problem was insignificant compared to others she faced.这一问题与她面临的其他问题比较起来算不得什么。

14 analogous   

adj.相似的；类似的

参考例句：

• The two situations are roughly analogous.两种情況大致相似。
• The company is in a position closely analogous to that of its main rival.该公司与主要竞争对手的处境极为相似。

15 spine   

n.脊柱，脊椎；(动植物的)刺；书脊

参考例句：

• He broke his spine in a fall from a horse.他从马上跌下摔断了脊梁骨。
• His spine developed a slight curve.他的脊柱有点弯曲。

16 perfectly   

adv.完美地，无可非议地，彻底地

参考例句：

• The witnesses were each perfectly certain of what they said.证人们个个对自己所说的话十分肯定。
• Everything that we're doing is all perfectly above board.我们做的每件事情都是光明正大的。

17 intelligible   

adj.可理解的，明白易懂的，清楚的

参考例句：

• This report would be intelligible only to an expert in computing.只有计算机运算专家才能看懂这份报告。
• His argument was barely intelligible.他的论点不易理解。

18 entirely   

ad.全部地，完整地；完全地，彻底地

参考例句：

• The fire was entirely caused by their neglect of duty. 那场火灾完全是由于他们失职而引起的。
• His life was entirely given up to the educational work. 他的一生统统献给了教育工作。

19 secondly   

adv.第二，其次

参考例句：

• Secondly,use your own head and present your point of view.第二，动脑筋提出自己的见解。
• Secondly it is necessary to define the applied load.其次，需要确定所作用的载荷。

20 glutinous   

adj.粘的，胶状的

参考例句：

• The sauce was glutinous and tasted artificial.这种酱有些黏，尝起来不是非常地道。
• The coat covering the soft candies is made from glutinous rice.包裹软糖的江米纸是由糯米做成的。

21 sinewy   

adj.多腱的，强壮有力的

参考例句：

• When muscles are exercised often and properly,they keep the arms firm and sinewy.如果能经常正确地锻炼肌肉的话，双臂就会一直结实而强健。
• His hard hands and sinewy sunburned limbs told of labor and endurance.他粗糙的双手，被太阳哂得发黑的健壮四肢,均表明他十分辛勤，非常耐劳。

22 apportioned   

vt.分摊，分配（apportion的过去式与过去分词形式）

参考例句：

• They apportioned the land among members of the family. 他们把土地分给了家中各人。
• The group leader apportioned them the duties for the week. 组长给他们分派了这星期的任务。 来自《现代汉英综合大词典》