Aug. 29, 1872] 



NATURE 



365 



when fissured as the right and left segments of the hver, reserving 

 the term lobe for the subdivisions. This will involve no am- 

 biguity, for the terms right and left lobes will no longer be used 

 for divisions of the more complex form of liver. 



In the large majority of mammals each segment is further 

 divided by a fissure more or less deep, extending from the free 

 towards tlie attached border, which 1 propose to call ri^/it and 

 /,■// hili-ral fissures (see Fig., rlf, and Ilf). When these are 

 more deeply cut than the umbilical fissure, llie organ has 

 that tripartite or trefoil-like form just spoken of, the part 

 between them being he so-called middle, cystic, or suspen- 

 sory lobe. These terms I should propose to discontinue, and to 

 insti:ute right ccittial {r l) and left icntral {t c) for the two regions 

 included between the umbilical and the two lateral fissures, and 

 to use right lateral {r I) and left lateral ill) for the regions beyond 

 the lateral fissures. The essentially bipartite character of the 

 organ, and the uniformity of its construction throughout the class, 

 is thus not lost sight of, even in the most complex forms. 



Tlie left segment of the liver is rarely complicated to any 

 further extent, except in some cases by minor or secondary 

 fissures marking off small lobules, generally inconstant and 

 irregular, and never worthy of any special designation. The 

 principal differences to be noted depend on the degree of com- 

 pleteness of the lateral fissure (which sometimes extends quite 

 across the hepatic tissue completely severing the left lateral lobe), 

 aud the relative size of the two lobes. 



On the other hand, the right segment is usually more complex. 

 The right lateral fissure when fully developed passes into tlie 

 right extremity of the portal fissure. The right central lobe, 

 therefore, on its under surface does not reach to the attached 

 border of the liver ; but is always bounded in that direction by 

 the portal fissure. Moreover, the gall-bladder when present is 

 always in relation to its under surface. The position of this 

 receptacle with respect to the lobe may vary — sometimes it is 

 merely applied to its surface, loosely connected hy connective 

 tissue ; in other cases it is deeply embedded in a fossa. Very 

 often it is placed near the middle of the lobe — sometimes close to 

 one or the i;lier of its lateral boundaries. In many cases the fossa 

 in which the gall-bladder is sunk is continued to the free margin 

 of the liver as an indent, or even a tolerably deep fissure. This 

 is called the cystic fissure (e f) ; but in consequence of its irregu- 

 larity of position and frequent absence it is not of the same im- 

 portance as the other fissures I have named, and does not mark 

 olT any distinct divisions of hepatic substance. 



The right lateral lobe always has the great vena cava (v c) either 

 grooving its surface or tunnelling through its substance near the 

 inner or left end of its attached border, and a prolongation to 

 the left, between the vein and the portal fissure, has long been 

 known under the name of the Spigelian lobe (s). This is always 

 a distinct hepatic region, sometimes a mere narrow, flat track, 

 but more often a prominent tongue-shaped process. Whatever 

 may be its form, it is bounded in front, or towards the free sur- 

 face oi the liver, by the portal fissure ; on the left by the fissure 

 of the ductus venosus (unless the vessel is bridged over by 

 hepatic substance) ; posteriorly and partially on the right by the 

 vena cava, but between this vessel and the right end of the por- 

 tal fissure it is continued onwards into the adjoining part oi the 

 right lateral lobe. 



The main body of the right lateral lobe is most commonly di- 

 vided into two parts, not by a cleft, such as the lateral fissures, 

 passing from the upper to the lower surface of the liver, but by 

 one which severs a part off" from the under surface. This is the 

 eeuJate lobe, and the fissure which separates it from the right 

 lateral lobe may be called the "fissure of the caudate lobe." In 

 man it is almost obsolete, but in most Mammals it is of very 

 considerable magnitude, and has very constant and characteristic 

 relations. It is connected by an isthmus at the left (narrowest 

 or attached end) to the spigelian lobe, behind whicli isthmus the 

 venr cava is always in relation to it, channelling through or 

 grooving its surface. It generally has a pointed apex, and is 

 deeply hollowed to receive the rigtit kidney, to the upper and 

 inner side of which it is applied. 



For ready comparison I have found it convenient to tint the 

 diagrams of different livers with the following colours ; — The left 

 central lobe, dark blue ; the left lateral, light blue. Where the 

 left lateral fissure is not present, as in man, the ruminants, and 

 cetacea, the colours will shade into each other, or the whole 

 segment may be made of a medium shade. The right central 

 lobe, dark red ; the right lateral, light red ; the spigelian, yellow ; 

 and the caudate brown. By this method the homologous parts 



of every liver, and the essential similarity of their construction, 

 however diverse in appearance, may be seen at a glance. * 



SECTION F— Economic Science and St.\tistics 



Report of the Committee appointed on Uniformity of Weights, 

 Pleasures, and Coins. 



The Metric Committee of the British Association has much 

 pleasure in reporting that another great stride has been made 

 towards the uniformity in the weights, measures, and coins of all 

 countries, by the passing of a law in Austria in June 1871, ren- 

 dering the use of metric weights and measures permissive fro n 

 January I, 1873, and compulsory from January I, 1876. The 

 metric system is gradually diffusing itself all over Europe. 

 At this moment fully two-tlriids of that continent measured by 

 population have adopted the metric system of weights and mea- 

 sures, and the other one-third has manifested sufficient interest 

 in the question to justify the expectation of its early adhesion 

 to the general agreement. But in this one-third there are com- 

 prised Russia and England, two countries which, by their pojiu- 

 lation and commerce, exercise an enormous influence in the whole 

 world. 



The state of the question in Russia appears to be as follows : — 

 In 1859 a Committee of the Imperial Academy of Russia, 

 issued a report on the subject, which approved of the de- 

 cimal division already incorporated in the Russian money 

 system, and expressed an opinion in favour of extending 

 such decimal divisions to weights and measures. In dis- 

 cussing, however, the possibility of even this moderate re- 

 form, the Academicians saw that such a considerable change 

 would be required that they felt it would be far better for 

 Russia at once to introduce the metric system, and this was 

 the conclusion of their recommendations. .Since the publication 

 of the report, the Imperial Academy of Russia has taken an 

 active part in advance of the system all over the world. In iS'67 

 Mr. Jacob! ^\"as a member of the International Committee on 

 weights, measures, and coins in connection with the Paris Intern i- 

 tioiial Exhibition, and wrote the report which was agreed to by the 

 representation of the nations who took part in the conference 

 on the subject. And later still, in 1S70, owing to the repre- 

 sentations of the Imperial Academy of Russia to the French 

 Government and to the scientific bodies of other nations of the 

 need of preparing more accurate and metric standards for the 

 use of countries which might adopt the metric system, an In- 

 ternational Committee was appointed to prepare such standards. 

 This Committee met in Paris, in June 1870, and will resume 

 its labours in September next. 



In the United Kingdom considerable progress has been made 

 towards the introduction of the metric system, though much cer- 

 tainly remains to be done. In 1S62 a Committee of the House 

 of Commons was appointed to consider the practicability of 

 adopting a simple .and uniform system of weights and measures, 

 with a view not only to the benefit of internal trade, but to facili- 

 tate our trade and intercourse with foreign countries. In dis- 

 cussing the question of the possible decimalisation of the existing 

 system, the Committee of the British House of Commons, in the 

 same manner as the Committee of the Imperial Academy of 

 Russia, reported that it would involve almost as much difficulty 

 to create a special decimal system of our own as simply to adopt 

 the metric decimal system in common with other nations. And 

 under the circumstances the Committee came to a unanimous 

 recommendation in favour of the introduction of the metiic 

 system. 



Nearly 200,000,000 of people in Europe have already recog- 

 nised the metric system as the international system of weights 

 and measures, 160,000,000 of whom have already adopted it in 

 a compulsory manner. If once, therefore, Russia and England 

 should finally place their legislation on the same footing, the 

 other smaller states will certainly follow, and Europe will have 

 attained perfect unity as regards weights and measures. But in 

 other parts of the world also considerable progress has been 

 made. In Asia the whole of India may be said to have adopted 

 the weights and measures of capacity of the metric system, 

 though some time may elapse before the Act passed by the 

 Indian Government can be carried into operation. 



In America the United States have introduced it permissively ; 



* The principal modifications from this common plan are described in 

 "Lectures on the Organs of Digestion in the MammaJia,"' in course of pub- 

 lication in the Medical rimes ami Gazette. 



