1.That sex ratio will be favored which maximizes the number of　descendants an individual will have and　hence the number of gene copies　transmitted. (来源：老牌的英语学习网站 http://www.EnglishCN.com)

那种性别比例能在最大程度上增加一个个体所能拥有的后代数量，并因此能在最大程度上增加所传递到后代身上去的基因复制品的数量。

2.Hardy"s weakness derived from his apparent inability to control the comings and goings of these divergent impulses and from his unwillingness to cultivate and sustain the energetic and　risky ones.

哈代的缺陷一方面缘起于他的某种明显的无能，无法控制好那结不尽相同的创作冲动的穿梭往来；另一方面缘起于他不愿意去培养和维持那些富于生机活力和风险性强的创作冲动。

3.Virginia Woolf"s provocative statement about her intentions in writing Mrs. Dalloway has regularly been　ignored by the critics，since it highlights an aspect of her literary interests very different from the traditional picture of the "poetic" novelist concerned with examining states　　of reverie and vision and with following the intricate pathways of individual consciousness.

弗吉尼亚.伍尔夫（Virginia Woolf）在创作《黛洛维夫人》（Mrs. Dalloway）时有关其创作意图的这番发人深思的陈述，迄今为止一贯为文学评论家们所忽略，因为它突出反映了她诸多文学兴趣中某一方面，而这一方面则与人们对“诗性”小说家（poetic novelist）所形成的传统见解大相径庭。所谓的“诗性”小说家，所关注的是审视想入非非和白日梦幻的诸般状态，并致力于追寻个体意识的通幽曲径。

4.Although Gutman admits that forced separation by sale was frequent，he shows that the slaves" preference，revealed most clearly on plantations where sale was infrequent，was very much for stable monogamy.

虽然古特曼承认，由于奴隶买卖而造成的被迫离散甚为频繁，但他还是证明，奴隶的偏爱——在那些奴隶买卖并不频繁的种植园上被最为显著地揭示出来——在很大程度上侧重于稳定的一夫一妻制（monogamy）。

5.Gutman argues convincingly that the stability of the Black family encouraged　the transmission of-and so was crucial in sustaining-the Black heritage of folklore，music，and religious expression from one generation to another，a heritage that slaves were continually fashioning out of their African and American experiences.

古特曼人令人信服地论辨道，黑人家庭的稳定有助于包括民间传说、音乐、及宗教表达在内的黑人文化遗产一代一代传递下去，因而在维持文化遗产方面也起着至关重要的作用，而对于这种文化遗产，黑奴们不断地从其非洲和美洲的经历中予以丰富发展。

6.This preference for exogamy，Gutman suggests， may have derived from　West African rules governing marriage，which，though they differed from one tribal group to another，all involved some kind of prohibition against unions with close kin.

古特曼表示，这种对于外部通婚的偏爱很有可能缘起于西部非洲制约着婚姻的规定，尽管这些规定在一个和另一个部落群体之间不尽相同，但都涉及到某种对近亲联姻（union with close kin）的禁止。

7.His thesis works relatively well when applied to discrimination against Blacks in the United States，but his definition of racial prejudice as "racially-based negative prejudgments against a group generally accepted as a race in any given region of ethnic competition，" can be interpreted as also including hostility toward such ethnic groups as the Chinese in California and the Jews　　in medieval Europe.

该社会学家的命题当被应用于针对美国黑人的歧视时，相对而言尚能适用，但他对种族偏见所下的定义——即“以种族为基础的、针对某个群体的消级的先入之见，而该群体在任何特定的种族竞争地区则被普遍认作一种族”——可被理解成同样也襄括了针对加利福尼亚州的中国人以及中世纪的犹太人这样一些种族群体的敌视态度。

8. Such variations in size， shape，chemistry， conduction speed， excitation threshold，and the like as had been demonstrated in nerve cells remained negligible in significance for any　　possible correlation with the manifold dimensions of mental experience.？？

9.Although qualitative variance among nerve energies was never rigidly disproved，the doctrine was generally abandoned in favor of the opposing view，namely，that nerve impulses are essentially homogeneous in quality and are transmitted as "common currency" throughout the nervous system. Other experiments revealed slight variations in the size，number，　　arrangement，and interconnection of the nerve cells，but as far as psychoneural correlations were concerned，the obvious similarities of these sensory fields to each other seemed much more remarkable than any of the minute differences. Although some experiments show that，as an object becomes familiar，its internal　representation becomes more holistic and　the recognition process correspondingly more parallel，the weight of evidence　seems to support the serial hypothesis，　　at least for objects that are not notably simple and familiar.

虽然某些实验表明，随着一个物体变得熟悉起来，其内心再现图像亦更具整体感，辨认过程相应地更趋于平行，但证据的砝码似乎在支持序列假设（serial hypothesis），至少是对于那些不甚简单、不甚熟悉的物体来说。

10.In large part as a consequence of　the feminist movement，historians have focused a great deal of attention in recent years on determining more accurately the status of women in　various periods.

在很大程度上，由于女权主义运动（feminist movement）的缘故，史学家近年来汇聚了大量的注意力，来更为准确地确定妇女在各个历史时期的地位。

11.Thus，for instance，it may come as a shock to mathematicians to learn that the Schrodinger equation for the hydrogen atom is not a literally correct description of this atom，but only an approximation to a somewhat more correct equation taking account of spin，magnetic dipole，and relativistic effects；and that this corrected　equation is itself only an imperfect approximation to an infinite set of　quantum field-theoretical equations.

因此，举例来说，对数学家而言，了解到下述情形可能会令其惊愕不已，即薛定谔（Schrodinger）的氢原子方程式并非是对该原子作出的一种绝然正确的描述，而仅仅是个近似值，趋近于一个在某种程度上更为正确的将自旋、磁性偶极子、以及相对论效应考虑在内的方程式；而这个得以纠正的方程式就其本身而言也只是一个不完美的近似值，趋近于无穷无尽的一整套量子场论方程式。

12.The physicist rightly dreads precise argument，since an argument that is　convincing only if it is precise loses all its force if the assumptions on　which it is based are slightly changed，whereas an argument that is convincing though imprecise may well be stable under small perturbations of its underlying assumptions.

物理学家恐惧于那些精确无误的论据不无道理，因为某种只有在它是精确无误的条件下才令人置信的论据，一旦它赖于建立其上的假设稍有变化，便会失去它一部的作用；而与此相反，一个尽管并不精确无误但却令人置信的论据，在其基本假设（underlying assumption）稍微受干扰的情况下，仍然有可能是站得住脚的。

13.However，as they gained cohesion，the Bluestockings came to regard themselves as a women"s group and to possess a sense of female solidarity lacking in the salonnieres，who remained isolated from one another by the primacy each held in her own salon.

起初，蓝袜女们确实模仿了法国沙龙女主人，将男性襄括到其小圈子中来。然则，随着她们获得的凝聚力，她们渐趋将自己视作一女性团体，并拥有了一种妇女团结意识，而这种意识在法国沙龙女主人身上则荡然无存，因为她们每个人在其自己的沙龙中自视甚高而彼此孤立隔绝开来。

14.As my own studies have advanced，I have been increasingly impressed with the functional　　similarities between insect and vertebrate societies and less so with the structural differences that seem，at first glance，to constitute such an immense gulf between them.

随着我的研究不断深入，我对昆虫和脊椎动物群落之间的功能类似性印象愈来愈深刻，而对结构上的差异印象愈发淡漠，虽然这些结构上的差异初看上去似乎构成了二者间一条无法愈越的鸿沟。

15. Although fiction assuredly springs from political circumstances，its authors react to those circumstances in ways other than ideological，and talking about novels and stories primarily as instruments of ideology circumvents much of the fictional enterprise.

虽然小说无疑起源于政治情状，但其作者则是以非意识形态的方式对这些政治情状作出反应的，而将小说和故事主要地当作意识形态的工具来探讨，会在相当程度上阻碍小说事业。

16.Is this a defect，or are the authors working out of，or trying to forge，a different kind of aesthetic？

这究竟是一种缺陷呢，或者是否表明，这些作者是在按照一种与众不同的美学体系进行创作，抑或是在试图创立一种与众不同的美学体系？

17.Black Fiction surveys a wide variety of novels，bringing to our attention in the　process some fascinating and little-known works like James Weldon　Johnson"s Autobiography of an Ex-　　Colored Man.

《黑人小说》考察了极为广泛的一系列小说，在此过程中让我们注意到了某些引人入胜但却鲜为人知的作品，如詹姆斯。韦尔登。约翰逊（James Weldon Johnson）的《一个曾经是有色人的自传》（Autobiography of an Ex-Colored Man）。

18.Although these molecules allow radiation at visible wavelengths， where most of the energy of sunlight is concentrated，to pass through，they absorb some of the longer-wavelength，　　infrared emissions radiated from the Earth"s surface，radiation that would　otherwise be transmitted back into space.

虽然这些分子允许可见波长（visible wavelength）的辐射——阳光的绝大部分能量就汇集于此——不受阻挡地穿透，但它们却会吸收某些较长波长（longer-wavelength），亦即从地球表面辐射出的红外发射（infrared cmission），这种辐射若不是二氧化碳的缘故就会被重新输送回太空。

19.The role those anthropologists ascribe to evolution is not of dictating　the details of human behavior but one　of imposing constraints—ways of　feeling，thinking，and acting that　　"come naturally" in archetypal situations in any culture.

这些人类学家所归诸于生物进化的作用，不是规定人类行为的种种细节，而是将各种限制强加于人类——即在任何文化的典型情景中都会“自然表露”的情感、思维、以及行动方式。

20.A low number of algal cells in the presence of a high number of grazers suggested，but did not prove， that the grazers　had removed most of the algae.

在存在大量食草动物的同时却只有少量的水藻花粉囊，这暗示出——但没能证明——食草动物已吞噬了大部分水藻。

21.Studies by Hargrave and Geen estimated natural community graz-ing rates by measuring feeding rates of　individual zooplankton species in the　laboratory and then computing community grazing rates for field conditions　using the known population density　of grazers.

由哈格雷夫（Hargrave）和吉恩（Geen）所进行的研究，对自然条件下的群落食草比例进行了估计，其手段是通过测量出实验室内单独的浮游动物种类的结食比例，然后利用已知的食草动物种群密度，计算出实地状况下的群落食草比例。

22.In the periods　of peak zooplankton abundance，that is，in the late spring and in the summer，　　Haney recorded maximum daily com-munity grazing rates，for nutrient-poor　lakes and bog lakes，respectively，of 6.6 percent and 114 percent of daily phytoplankton production.

在浮游动物数量激增的高峰期，亦即在春季后期以及夏季，哈尼记录了最大程度上的每日群落食草比率，对于营养物不充足的湖和沼泽湖而言，分别为每日浮游植物繁殖量的6.6%和114%.

23.The hydrologic cycle，a major topic in this science，is the complete cycle of phenomena through which water passes，beginning as atmospheric water vapor，passing into liquid and solid form as precipitation，thence along and into the ground surface，and finally again returning to the form of atmospheric water vapor by means of evaporation and transpiration.

水文循环（hydrologic cycle），作为该学科中的一个主要课题，指的是水所经过的诸现象的整个循环过程，开始时是作为大气中的水蒸气，转而作为雨、雪、露、雹一类的降水量经过液体和固体形态，由此而沿着地层表面分布或进入地层表面，最终通过蒸发和散发作用再度回复到大气水蒸气的形态。

24.The historian Frederick J. Turner wrote in the 1890"s that the agrarian discontent that had been developing　steadily in the United States since about 1870 had been precipitated by the　　closing of the internal frontier——that is，the depletion of available new land　needed for further expansion of the American farming system.

史学家弗雷德里克.杰.特纳（Frederick J.Turner）于十九世纪九十年代著述道，美国约自18世纪70年代以来一直在持续不断发展的农民不满，由于国内边远地区（internal frontier）的封闭而更趋加剧——亦即是说，美国农业系统进一步扩展所必需的可资利用的新土地几近耗竭。

25.In the early 1950"s，historians who studied preindustrial Europe （which we may define here as Europe in the period from roughly 1300 to 1800） began， for the first time in large numbers，to　　investigate more of the preindustrial European population than the 2 or 3 percent who comprised the political　and social elite：the kings，generals，judges，nobles，bishops，and local　magnates who had hitherto usually filled history books.

二十世纪五十年代早期，研究前工业化时代欧洲（此处我们可将其界定为约自1300年至1800年这一时期的欧洲）的史学家，首次以众多的人数，开始调查前工业化时代欧洲人口中的大多数，而非那些构成了政治与社会精英阶层的百分之二或三的人口，即国王、将军、法官、贵族、主教、以及地方上的达官显贵，而正是这部分人一直到那时为止普遍充斥于史学著作。

26.Historians such as Le Roy Ladurie　have used the documents to extract case　histories， which have illuminated the attitudes of different social groups （these attitudes include，but are not　　confined to，attitudes toward crime and　the law）and have revealed how the authorities administered justice.

象勒罗伊。拉迪里（Le Roy Ladurie）一类的史学家利用这些文献史料从中挖掘出某些个案史（case history）来，阐明了不同社会群体的态度（这些态度包括，但并非局限于，对犯罪和法律的态度），并揭示出当局是如何执行审判的。

27.My point is that its central　consciousness—its profound understanding of class and gender　　as shaping influences on people"s lives—owes much to that earlier literary heritage，a heritage that，in general，has not been sufficiently valued by most contemporary literary critics.

我的论点是，其作品的中心意识——它将阶级和性别作为人们生活的决定性影响而作出的深邃理解——在很大程度上借鉴了那个早期的文学遗产，而这一遗产就总体而言还尚未获得大多数当代文学评论家的足够重视。

28.But achieving necessary matches in physical properties across interfaces between living and　　nonliving matter requires knowledge of which molecules control the bonding of cells to each other—an area that we have not yet explored thoroughly.

但是，要想沿着原生和非原生物质之间的界面获取生理特性的必要匹配，需要某种知识，即什么样的分子控制着细胞彼此间的结合——而对这一领域，我们尚未进行充分的探索。

29.Islamic law is a phenomenon so different from all other forms of law—notwithstanding，of course，a　considerable and inevitable number of coincidences with one or the other　of them as far as subject matter and positive enactments are concerned—that its study is indispensable in order to　appreciate adequately the full range of　possible legal phenomena.

伊斯兰法是一种如此不同于所有其它法律形式的现象——毋庸置疑，尽管就其主要内容和有积极意义的法规而言，与其它法律形式中的这种或那种形式存在着相当数量的且不可避免的巧合相似之处——以致于对它进行研究便显得不可或缺，以便充分理解有可能存在的法律现象的全部范围。

30.Though historically there is a discernible break between Jewish law of the sovereign state of ancient Israel and of the Diaspora （the dispersion of Jewish people after the conquest of Israel）， the spirit of the legal matter in later parts of the Old Testament is very close to that of the Talmud， one of the primary codifications of Jewish law in the Diaspora.

尽管从历史角度来看，在古代以色列作为独立主权国家的犹太教法与大流散时期（Diaspora，即以色列被征服后古代犹太人被巴比伦人逐出故土）的犹太教法之间存在着一个明晰可辨的断裂，然则，《旧约全书》（Old Testament）后半部分中法律内容的精神与《犹太教法典》（Talmud）极为一脉相承，而所谓的《犹太教法典》，是指大流散时期犹太教法的主要典籍辑录之一。

31.Islam，on the other hand，represented a radical breakaway from the Arab paganism that preceded it；Islamic law is the result of an examination　from a religious angle，of legal subject　　matter that was far from uniform，comprising as it did the various components of the laws of pre-Islamic　Arabia and numerous legal elements　taken over from the non-Arab peoples　of the conquered territories.

另一方面，伊斯兰教则代表着与此前存在的阿拉伯异教（Arab paganism）的一种根本上的决裂；伊斯兰法是从宗教的角度，对各种杂乱无章、绝无共同点的法律内容进行考察所致的结果，而这些法律内容实际上是由前伊斯兰阿拉伯国家（Pre-Islamic Arabia）法律的不尽相同的组成部分以及由从被征服的土地上非阿拉伯民族借鉴过来的无数法律因素所构成。

32.One such novel idea is　that of inserting into the chromosomes of plants discrete genes that are not a part of the plants" natural constitution：specifically，the idea of inserting into　　nonleguminous plants the genes，if they can be identified and isolated，that fit the leguminous plants to be hosts for nitrogen-fixing bacteria. Hence，the intensified research on legumes.

这其中的一个新颖思想就是，在植物的染色体（chromosome）内注入并非是该植物自然构造一个部分的那些不相关联的因基：具体而言，这一思想是，在非豆科植物内注入这样一些基因，倘若这些基因可被辨识出来并被分离开来，而这些基因业已使豆科植物宜于充当那些具备固氮作用的细菌的寄主。由此，对豆科植物的研究日趋深入。

33.It is　one of nature"s great ironies that the　availability of nitrogen in the soil frequently sets an upper limit on plant growth even though the plants" leaves　are bathed in a sea of nitrogen gas.下述情形真可谓是自然界的一个莫大讽刺：土壤中所能获得的氮肥量往往对植物的生长构成了一个上限，虽然植物的叶子被沐浴在一片氮气的海洋中。

34.Unless they succeed，the　yield gains of the Green Revolution will be largely lost even if the genes in　legumes that equip those plants to enter　into a symbiosis with nitrogen fixers　are identified and isolated，and even if　the transfer of those gene complexes，once they are found， becomes possible.

除非他们能取得成功，不然的话，绿色革命的产量收益将在很大程度上损失殆尽，即使豆科植物中使这些植物有条件进入到与固氮细菌共生关系的基因可被辨识出来和分离开来的话，且即使这些基因综合体（gene complex），一旦被发现之后，其移植得以成为可能的话。

35.Its subject（to use Maynard Mack"s categories）is　"life-as-spectacle，" for readers，　　diverted by its various incidents，observe its hero Odysseus primarily from without；the tragic Iliad，however，presents "life-as-experience"：readers　are asked to identify with the mind of　　Achilles，whose motivations render him a not particularly likable hero.

其主题〔若借鉴梅纳德。迈克（Maynard Mack）的两个分类范畴的话〕是“人生作为外部景象”，因为读者的注意力被作品那形形色色的事件所分散，主要是从外部来观察其主人公奥德修斯（Odyssus）的；然而，富于悲剧色彩的《伊利亚特》所表现的则是“人生作为内心体验”：读者被要求与阿基琉斯（Achilles）的心灵产生共鸣，而其行为动机却致使他变作一个并非特别惹人喜爱的主人公。

36.Most striking among the many asymmetries evident in an adult flatfish is eye placement： before maturity one eye migrates，so that in an adult flatfish both eyes are on the same side of the head.

在一条成年比目鱼身上显著存在的诸多不对称（asymmetry）特征中，最为吸人注目的是眼睛的摆位：在成年之前，一只眼睛发生移动，因此在成年比目鱼身上，两只眼睛均位于头部的同一侧面。

37.The best evidence for the layered-mantle thesis is the well-established fact that volcanic rocks found on oceanic islands，islands believed to result from mantle plumes arising from the lower mantle，are composed of material fundamentally different from that of the midocean ridge system， whose source，most　geologists contend，is the upper mantle.

对于地幔分层论点来说，最好的证据乃这样一个确认的事实，即在那些海洋岛屿——这些岛屿据信是源于由下层地幔升上来的地幔柱状溶岩流（mantle plume）——上发现的火山岩石，是由与海洋中部山脊系统的物质根本不同的物质构成的，而这一海洋中部山脊系统的成因，大多数地质学家论辩道，为上部地幔。

38.Some geologists，however，on the basis of observations concerning mantle　xenoliths， argue that the mantle is　not layered，but that heterogeneity is created by fluids rich in "incompatible elements" （elements tending toward　liquid rather than solid state）percolating upward and transforming　portions of the upper mantle　irregularly，according to the vagaries of the fluids" pathways.

但是，某些地质学家，以对地幔捕虏岩体（xenolith）所作的观察为依据，指出地幔并非是分层排列的，相反，地幔的异质性是由那些富含“不相容成分”的流质构成的，这些成分趋向于流体而非固体的状态，自下而上渗透扩散，并依照这些流质流向的任意性，不规则地将上部地幔的某些部分予以改变。

39.The very richness and complexity of the　meaningful relationships that kept　presenting and rearranging themselves　on all levels，from abstract intelligence to profound dreamy feelings， made it difficult for Proust to set them out coherently.

各种有意义的联系在所有的层次上，自抽象的理性至深刻的梦幻般的情感，层出不穷并不断重新组合排列；正是这些有意义的联系的丰富性和复杂性，致使普鲁斯特难于将它们错落有致地安排好。

40.It is possible to make specific complementary DNA"s （cDNA"s）that can serve as molecular probes to seek out the messenger RNA"s （mRNA"s）of the peptide hormones. If brain cells are making the hormones，the cells will contain these Mrna"S. If the products the brain cells make resemble the hormones but are not identical to them，then the cDNA"s should still bind to　　these mRNA"s，but should not bind as tightly as they would to mRNA"s for the true hormones.

科学家可以制造出特异的（specific）互补DNA"s（cDNA"s），以此作为分子探子（molecular probe），探觅出肽激素的信使RNA"s（mRNA"s）。如果大脑正在制造着肽激素，则细胞就会含有这些信使RNA"s.假若细胞所制造的产品类似于肽激素但并非与这些肽激素全然相同，那么，互补cDNA"s应仍然和这些信使mDNA"s粘结的程度。含有这些mRNA"s的脑细胞然后就可以被分离开来，研究者可对其信使RNA"s进行解码，以确定它们的蛋白质产品究竟是什么，并确定这些蛋白质产品在何种程度上类似于真正的肽激素。

41.The molecular approach to detecting peptide hormones using cDNA probes should also be much faster than the immunological method because it can　take years of tedious purifications　　to isolate peptide hormones and then develop antiserums to them.

采用cDNA探子来测定肽激素的这一分子生物学方法同时也应该比免疫学的方法速度来得快，因为对于免疫的方法来说，需耗费好几年枯燥的提纯进程，方能将肽素分离了出来，然后再培养出针对它们的抗血清。

42.This succession was based primarily on a series of deposits　and events not directly related to　　glacial and interglacial periods，rather　than on the more usual modern method of studying biological remains found in interglacial beds themselves interstratified within glacial deposits.

这一序列演替（succession）所依据的，主要是一系列与冰川期和间冰期并不直接相关的地质沉积物和地质事件，而不是依据更为普遍的现代方法，去研究间冰层（interglacial bed）中所发现的生物残留物，而这些间冰层本身又在冰川沉积物发生间层化（interstatified）。

43.There have been attempts to explain these taboos in terms of inappropriate social　　relationships either between those who are involved and those who are　not simultaneously involved in the satisfaction of a bodily need，or　between those already satiated and　those who appear to be shamelessly gorging.

人们试图对这些禁忌作出解释，所依据的要么是那些正置身于某一身体需要满足的人与那些并置身于某一身体需要之满足的人之间的，要么是那些早已酒足饭饱的人与那些正在不知羞耻地狼吞虎咽失之间的不相称的社会关系。

44.Many critics of Family Bronte"s novel Wuthering Heights see its second　part as a counterpoint that comments on，if it does not reverse，the first part，where a "romantic" reading receives more confirmation.

研究艾米丽。勃朗特（Emily Bronte）小说《呼啸山庄》（Wuthering Heights）的许多文学评论家，将小说的第二部分视作一种对比物，即使没有将第一部分予以逆转的话，也是在对第一部分作出一种诠释评判，而在小说第一部分中，一种“浪漫的”的读解能获得更为充分的确证。

45.Granted that the presence　of these elements need not argue an　authorial awareness of novelistic　construction comparable to that of Henry James， their presence does（15） encourage attempts to unify the novel"s　heterogeneous parts.

诚然，这些因素的存在并不能证明作者对小说架构的意识可与亨利。詹姆斯（Henry James）的那种意识相比拟；然则，任何力图将小说所有形形色色的因素统一起来的做法，在某种程度上注定是无法令人信服的。

46.This is not because such an interpretation necessarily stiffens into a thesis（although rigidity in any interpretation of this or of any novel is always a　danger），but because Wuthering Heights has recalcitrant elements of undeniable power that，ultimately，resist inclusion in an all-encompassing　interpretation.

这倒不是因为这样的一种解释必定会僵化成为一个命题（尽管对这部或任何一部小说的解释中，僵化死板总是一种危险），而是因为《呼啸山庄》拥有一些极难驾御的因素，以其无可辩驳的力度，最终拒绝被囿于一个囊括无遗的解释中。

47.The isotopic composition of lead often varies from one source of common copper ore to another，with variations exceeding the measurement error；and preliminary studies indicate　　virtually uniform is topic composition of the lead from a single copper-ore source.

铅的同位素构成经常在一种普通铜矿石来源与另一种铜矿石来源之间存在差异，其差异程度超出测量误差；而最初的研究表明，对于来自单独一个铜矿石来源的铅来说，其同位素构成几乎是毫无二致的。

48. More probable is bird transport，either externally，by accidental attachment of the seeds to feathers，or internally，by the swallowing of fruit and subsequent　excretion of the seeds.

更有可能的是鸟类运输：或者是通过外部途径，即由于种籽偶然粘附在羽毛上；或者是通过内部方式，即由于鸟类吞食果子并随后将种籽排泄出来。

49.It is not known how rare this resemblance is，or whether it is most often seen in　inclusions of silicates such as garnet，whose crystallography is generally somewhat similar to that of diamond；　　but when present，the resemblance is regarded as compelling evidence that the diamonds and inclusions are truly cogenetic.

现在尚不知这种类似稀少到何种地步，也不知道是否它最常见于象石榴石一类的硅酸盐内含物中，而这类物质的晶体结构普遍地在某种程度上类似于金刚石的晶体结构。但一旦存在，这种类似就被视作极有说服力的证据，证明金刚石与内含物确是同源的。

50.Even the "radical" critiques　of this mainstream research model，such as the critique developed in Divided Society，attach the issue of ethnic assimilation too mechanically to factors of economic and social　mobility and are thus unable to illuminate the cultural subordination　of Puerto Ricans as a colonial minority.

即使是对这一主流研究模型的“激进”批评，诸如《分裂的社会》（Divided Society）一书中所提出的那种批判，亦将少数民族同化问题过分机构地与经济和社会移动性的因素联系起来，因此无从阐明波多黎各人作为一个殖民地少数民族的文化从属关系。