Book IV chapter 6

Some of the vivipara produce their young imperfect, others perfect; the one-hoofed and cloven-footed perfect, most of the many-toed imperfect. The reason of this is that the one-hoofed produce one young one, and the cloven-footed either one or two generally speaking; now it is easy to bring the few to perfection. All the many-toed animals that bear their young imperfect give birth to many. Hence, though they are able to nourish the embryos¹ while newly formed, their bodies are unable to complete the process when the embryos have grown and acquired some size. So they produce them imperfect, like those animals which generate a scolex, for some of them when born are scarcely brought into form at all, as the fox, bear, and lion, and some of the rest in like manner; and nearly all of them are blind, as not only the animals mentioned but also the dog, wolf, and jackal. The pig alone produces both many and perfect young, and thus here alone we find any overlapping³; it produces many as do the many-toed animals, but is cloven-footed or solid-hoofed (for there certainly are solid-hoofed swine). They bear, then, many young because the nutriment which would otherwise go to increase their size is diverted to the generative secretion⁴ (for considered as a solid-hoofed animal the pig is not a large one), and also it is more often cloven-hoofed, striving as it were with the nature of the solid-hoofed animals. For this reason it produces sometimes only one, sometimes two, but generally many, and brings them to perfection before birth because of the good condition of its body, being like a rich soil — which has sufficient and abundant nutriment for plants.

The young of some birds also are hatched imperfect, that is to say blind; this applies to all small birds which lay many eggs, as crows and rooks, jays, sparrows, swallows, and to all those which lay few eggs without producing abundant nourishment⁵ along with the young, as ring-doves, turtle-doves, and pigeons. Hence if the eyes of swallows while still young be put out they recover their sight again, for the birds are still developing, not yet developed, when the injury is inflicted⁶, so that the eyes grow and sprout⁷ afresh. And in general the production of young before they are perfect is owing to inability to continue nourishing them, and they are born imperfect because they are born too soon. This is plain also with seven-months children, for since they are not perfected it often happens that even the passages, e.g. of the ears and nostrils⁸, are not yet opened in some of them at birth, but only open later as they are growing, and many such infants survive.

In man males are more often born defective⁹ than females, but in the other animals this is not the case. The reason is that in man the male is much superior to the female in natural heat, and so the male foetus moves about more than the female, and on account of moving is more liable to injury, for what is young is easily injured since it is weak. For this same reason also the female foetus is not perfected equally with the male in man (but they are so in the other animals, for in them the female is not later in developing than the male). For while within the mother the female takes longer in developing, but after birth everything is perfected more quickly in females than in males; I mean, for instance, puberty, the prime of life, and old age. For females are weaker and colder in nature, and we must look upon the female character as being a sort of natural deficiency. Accordingly while it is within the mother it develops slowly because of its coldness (for development is concoction¹⁰, and it is heat that concocts¹¹, and what is hotter is easily concocted); but after birth it quickly arrives at maturity¹² and old age on account of its weakness, for all inferior things come sooner to their perfection or end, and as this is true of works of art so it is of what is formed by Nature. For the reason just given also twins are less likely to survive in man if one be male and one female, but this is not at all so in the other animals; for in man it is contrary to Nature that they should run an equal course, as their development does not take place in equal periods, but the male must needs be too late or the female too early; in the other animals, however, it is not contrary to Nature. A difference is also found between man and the other animals in respect of gestation¹³, for animals are in better bodily condition most of the time, whereas in most women gestation is attended with discomfort¹⁴. Their way of life is partly responsible for this, for being sedentary they are full of more residual¹⁵ matter; among nations where the women live a laborious¹⁶ life gestation is not equally conspicuous¹⁷ and those who are accustomed to work bear children easily both there and elsewhere; for work consumes the residual matter, but those who are sedentary have a great deal of it in them because not only is there no monthly discharge during pregnancy¹⁸ but also they do no work; therefore their travail¹⁹ is painful. But work exercises them so that they can hold their breath, upon which depends the ease or difficulty of child-birth. These circumstances then, as we have said, contribute to cause the difference between women and the other animals in this state, but the most important thing is this: in some animals the discharge corresponding to the catamenia is but small, and in some not visible at all, but in women it is greater than in any other animal, so that when this discharge ceases owing to pregnancy they are troubled (for if they are not pregnant they are afflicted²⁰ with ailments²¹ whenever the catamenia do not occur); and they are more troubled as a rule at the beginning of pregnancy, for the embryo² is able indeed to stop the catamenia but is too small at first to consume any quantity of the secretion; later on it takes up some of it and so alleviates²² the mother. In the other animals, on the contrary, the residual matter is but small and so corresponds with the growth of the foetus, and as the secretions²³ which hinder nourishment are being consumed by the foetus the mother is in better bodily condition than usual. The same holds good also with aquatic²⁴ animals and birds. If it ever happens that the body of the mother is no longer in good condition when the foetus is now becoming large, the reason is that its growth needs more nourishment than the residual matter supplies. (In some few women it happens that the body is in a better state during pregnancy; these are women in whose body the residual matter is small so that it is all used up along with the nourishment that goes to the foetus.)

1 embryos   

n.晶胚；胚，胚胎( embryo的名词复数 )

参考例句：

• Somatic cells of angiosperms enter a regenerative phase and behave like embryos. 被子植物体细胞进入一个生殖阶段，而且其行为象胚。 来自辞典例句
• Evolution can explain why human embryos look like gilled fishes. 进化论能够解释为什么人类的胚胎看起来象除去了内脏的鱼一样。 来自辞典例句

2 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。

3 overlapping   

adj./n.交迭（的）

参考例句：

• There is no overlapping question between the two courses. 这两门课程之间不存在重叠的问题。
• A trimetrogon strip is composed of three rows of overlapping. 三镜头摄影航线为三排重迭的象片所组成。

4 secretion   

n.分泌

参考例句：

• Is there much secretion from your eyes?你眼里的分泌物多吗？
• In addition,excessive secretion of oil,water scarcity are also major factors.除此之外，油脂分泌过盛、缺水也都是主要因素。

5 nourishment   

n.食物，营养品；营养情况

参考例句：

• Lack of proper nourishment reduces their power to resist disease.营养不良降低了他们抵抗疾病的能力。
• He ventured that plants draw part of their nourishment from the air.他大胆提出植物从空气中吸收部分养分的观点。

6 inflicted   

把…强加给，使承受，遭受( inflict的过去式和过去分词 )

参考例句：

• They inflicted a humiliating defeat on the home team. 他们使主队吃了一场很没面子的败仗。
• Zoya heroically bore the torture that the Fascists inflicted upon her. 卓娅英勇地承受法西斯匪徒加在她身上的酷刑。

7 sprout   

n.芽，萌芽；vt.使发芽，摘去芽；vi.长芽，抽条

参考例句：

• When do deer first sprout horns?鹿在多大的时候开始长出角？
• It takes about a week for the seeds to sprout.这些种子大约要一周后才会发芽。

8 nostrils   

鼻孔( nostril的名词复数 )

参考例句：

• Her nostrils flared with anger. 她气得两个鼻孔都鼓了起来。
• The horse dilated its nostrils. 马张大鼻孔。

9 defective   

adj.有毛病的，有问题的，有瑕疵的

参考例句：

• The firm had received bad publicity over a defective product. 该公司因为一件次品而受到媒体攻击。
• If the goods prove defective, the customer has the right to compensation. 如果货品证明有缺陷， 顾客有权索赔。

10 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。

11 concocts   

v.将（尤指通常不相配合的）成分混合成某物( concoct的第三人称单数 )；调制；编造；捏造

参考例句：

• She concocts wonderful soup. 她调制美味的汤。 来自互联网
• To help his teammate, Krillin concocts an outlandish plan that you'll have to see to believe! 为了帮助他的战友，小林想出了一个绝妙的怪招。这可真是你必须亲眼见到才能相信的一招！ 来自互联网

12 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。

13 gestation   

n.怀孕；酝酿

参考例句：

• The gestation period can be anything between 95 and 150 days.妊娠期从95天至150天不等。
• This film was two years in gestation.这部电影酝酿了两年。

14 discomfort   

n.不舒服，不安，难过，困难，不方便

参考例句：

• One has to bear a little discomfort while travelling.旅行中总要忍受一点不便。
• She turned red with discomfort when the teacher spoke.老师讲话时她不好意思地红着脸。

15 residual   

adj.复播复映追加时间；存留下来的，剩余的

参考例句：

• There are still a few residual problems with the computer program.电脑程序还有一些残留问题。
• The resulting residual chromatism is known as secondary spectrum.所得到的剩余色差叫做二次光谱。

16 laborious   

adj.吃力的，努力的，不流畅

参考例句：

• They had the laborious task of cutting down the huge tree.他们接受了伐大树的艰苦工作。
• Ants and bees are laborious insects.蚂蚁与蜜蜂是勤劳的昆虫。

17 conspicuous   

adj.明眼的，惹人注目的；炫耀的，摆阔气的

参考例句：

• It is conspicuous that smoking is harmful to health.很明显，抽烟对健康有害。
• Its colouring makes it highly conspicuous.它的色彩使它非常惹人注目。

18 pregnancy   

n.怀孕，怀孕期

参考例句：

• Early pregnancy is often accompanied by nausea.怀孕早期常有恶心的现象。
• Smoking during pregnancy increases the risk of miscarriage.怀孕期吸烟会增加流产的危险。

19 travail   

n.阵痛；努力

参考例句：

• Mothers know the travail of giving birth to a child.母亲们了解分娩时的痛苦。
• He gained the medal through his painful travail.他通过艰辛的努力获得了奖牌。

20 afflicted   

使受痛苦，折磨( afflict的过去式和过去分词 )

参考例句：

• About 40% of the country's population is afflicted with the disease. 全国40%左右的人口患有这种疾病。
• A terrible restlessness that was like to hunger afflicted Martin Eden. 一阵可怕的、跟饥饿差不多的不安情绪折磨着马丁·伊登。

21 ailments   

疾病（尤指慢性病），不适( ailment的名词复数 )

参考例句：

• His ailments include a mild heart attack and arthritis. 他患有轻度心脏病和关节炎。
• He hospitalizes patients for minor ailments. 他把只有小病的患者也送进医院。

22 alleviates   

减轻，缓解，缓和( alleviate的名词复数 )

参考例句：

• Heat often alleviates pain. 热常常能减缓疼痛。
• A cold compress often alleviates pain. 冷敷常会减轻疼痛。

23 secretions   

n.分泌（物）( secretion的名词复数 )

参考例句：

• Lysozyme is an enzyme found in egg white, tears, and other secretions. 溶菌酶是存在于卵白、泪和其他分泌物中的一种酶。 来自辞典例句
• Chest percussion and vibration are used with postural drainage to help dislodge secretions. 在做体位引流时要敲击和振动胸部帮助分泌物松动排出。 来自辞典例句

24 aquatic   

adj.水生的，水栖的

参考例句：

• Aquatic sports include swimming and rowing.水上运动包括游泳和划船。
• We visited an aquatic city in Italy.我们在意大利访问过一个水上城市。