November ig, 1891] 



NATURE 



69 



of living things, or that department which deals with the mode 

 of life of organisms — habits, relation to the environment, &c. ; 

 the former use of the term is almost universal in English- 

 speaking countries, but many of the leading German writers 

 give it the other signification. Again, morphology zxvA anatomy 

 are terms of fundamental importance, and zoologists and bota- 

 nists might surely agree upon a common definition for each. The 

 same applies to other terms common to the two sub-sciences, 

 ovary being the most flagrant example of divergence. To take 

 one more example, the word biogenesis was introduced by Prof. 

 Huxley to signify the origin of organisms from preexisting 

 organisms. Eiiner, in his recent work on organic evolution, uses 

 the term biogenetic law for the law that individual recapitulates 

 ancestral development. 



Another matter, which might certainly be settled once for all, 

 is the meaning to be attached to adjectives and prefixes denoting 

 position, such as dorsal and ventral, anterior and posterior, 

 proximal and distal, mesial and lateral, epi-, hypo-, pre-, post-, 

 &c. Such terms of position, although easy enough to apply in 

 most cases, are constantly being misused ; epiptibis {{ox pre- pubis) 

 is a modern and widely-used term ; the dorsal and ventral roots 

 of the spinal nerves are still frequently called anterior zx\A. pos- 

 terior, and the great body-veins the superior and inferior venze 

 cavoe ; and the botanical use of many terms of position (i?.^. 

 the rt'i?ri'a/ and z/ifM/ra/ sutures of a carpel) is absolutely mean- 

 ingless. 



Another step in the right direction would be the publication, 

 under the auspices of the British, American, and Australasian 

 Associations, the Anatomische Gesellschaft, and similar bodies, 

 of a glossary of biological terms, in which the history of the 

 word, its inventor, the precise sense in which he used it, and 

 any subsequent changes of meaning it may have undergone, 

 would be set forth. Such a glossary might, I think, be usefully 

 arranged under somewhat similar headings to those employed 

 in the Zoologischer Jahresbericht, the whole work being of 

 course supplied with an alphabetical index. With a single 

 responsible editor, and a sub-editor for each department, the 

 work would not be one of insuperable difficulty. 



An even more practicable suggestion than the last, and one 

 which, although supplementary to, is not dependent upon it, is 

 that in such publications as the Zoological Record, the Journal 

 of the Royal Microscopical Society, and the Zoologischer Jahres- 

 bericht, there should be a record of new terms as well as of new 

 species. The recorders who do the work of these publications 

 with such fidelity and success, would hardly find their labours 

 increased by noting down all the new terms used by the authors 

 in their various departments, and placing them in a special list, 

 each being accompanied byname of author, date, and definition. 

 If this were done, we should have fewer instances both of useless 

 synonyms and of identical words being employed for totally dis- 

 tinct things. I do not think, for instance, that the body-cavity 

 of Peripatus would have been called sl pseudoca-le by Mr. Sedg- 

 wick, or a metacccle by Mr. Hatchett Jackson, if these writers 

 had had the means of knowing that the former term had been 

 previously applied by Dr. Burt Wilder to the so-called fifth 

 ventricle of the mammalian brain, and the latter to the fourth 

 ventricle. 



Finally, matters would be very much improved if every author 

 who finds himself obliged to coin a word would notify the fact 

 in a conspicuous part of his paper, accompanying the term with 

 an adequate definition. One has only to point to Allman's 

 monograph on the Gymnoblastic Hydroids, or to Haeckel's 

 Report on the Deep- Sea Medusre, to give a practical instance 

 of the advantage of such a practice. 



My proposals for promoting greater uniformity of nomencla- 

 ture in biology may therefore be summed up under three heads, 

 as follows : — 



1. The appointment of a strong international committee to 

 define terms of general and fundamental importance, such as 

 the subdivisions of biological science, terms common to zoology 

 and botany, terms denoting position, &c. 



2. The issue of an authoritative historical glossary. 



3. The systematic record of new terms. 



METEORIC IRON. 

 'T'HE Annalen des k.k. naturh. Ho/museums, No. 2 of vol. 

 -^ vi., contains a further contribution by E. Cohen and E. 

 Weinschenk to their interesting studies on meteoric irons. 



By treating comparatively large masses in the cold with very 



dilute hydrochloric acid (l in 20) so that the process of solution 

 was very slow, in some cases extending to several months, a 

 residue is left from which it is found possible to isolate several 

 more or less definite compounds, distinct from the freely soluble 

 main mass of the meteorite. 



It is in the portion insoluble in the highly dilute acid, which 

 in some cases amounts to no more than 5 per cent, of the whole, 

 that the main interest in analytical work on meteoric irons 

 centres. The patience and care involved in the separation of 

 its various constituents often find their reward in some interesting 

 dii^covery. As a typical example of the constituents into which 

 a meteorite may be separated by this treatment with dilute acid, 

 it will suffice^-to quote the percentage numbers obtained in the 

 case of a slice of the Magura iron. They are as follows : — 



Nickel-iron which passed into solution 92*67 per cent. 



Cohenite ... 4'00 ,, 



Taenite -h jagged fragments o*i3 ,, 



Schreibersite 0*09 ,, 



Tsenite -f cohenite 2*93 ,, 



Non-magnetic residue o'i8 ,, 



In most meteoric irons the soluble portion consists to a large 

 extent of a nickel-iron kamacite, which mainly constitutes the 

 broad layers of the Widmanstatten figures seen on an etched 

 polished surface. The authors are of opinion, from a comparison 

 of various analyses, that this alloy has a constant composition re- 

 presented by the formula Fei4Ni. 



Cohenite, which occurs in very brittle tin-white crystals, has 

 at present been only found in the Magura iron. It was analyzed 

 and described in a previous paper by Dr. Weinschenk, wha 

 found it to consist of a definite carbide of iron, nickel, and cobalt, 

 having the composition represented by the formula (FeNiCo)3C, 

 Very similar crystals in the Wichita iron were found to have the 

 composition represented by the formula (FeNiCo)4C, analogous 

 to the well-known spiegeleisen, Fe4C. Cohenite corresponds ta 

 the carbide FcjC, which separates out in crystals when cast-iroa 

 is slowly cooled between 600° and 700°. Many points of re- 

 semblance such as this between meteoric and ordinary cast-iron 

 appear to show that the conditions as regards temperature, &c., 

 during their production must have, been very similar in the two 

 cases. 



Tsenite, occurring usually in thin silver-white lamellae ot 

 great toughness between the broader layers of kamacite, is a 

 nickel-iron, of which there appear to be two varieties, contain- 

 ing respectively about 65 and 73 per cent, of iron. Further 

 analyses, however, are necessary in order to determine its true 

 composition. The jagged and angular fragments of iron-black 

 colour were analyzed, and found to consist of a nickel-iron con- 

 taining about 7 per cent, of nickel, and were thus in all 

 probability identical with kamacite. 



The phosphor-nickel-iron schreibersite is generally found in 

 large tabular crystals of tin-white colour. The new analyses 

 show that its composition may be represented by the formula 

 (FeNiCo)3P. In some meteorites a phosphor-nickel-iron 

 occurring in needles is found. This is the so-called rhabdite of 

 Rose. Whether it is identical or not with schreibersite has not 

 yet been decided, owing to the difficulty of obtaining pure 

 material. A non-magnetic residue, consisting chiefly of trans- 

 parent grains, the authors find is common in greater or less 

 amount to most meteoric irons. In such residues a great variety 

 of minerals have been identified with more or less certainty, such 

 as diamond, cliftonite (a graphitic pseudomorph after diamond), 

 quartz, tridymite, chromite, cordierite, garnet, corundum, 

 pyroxenes both rhombic and monoclinic, &c. 



The aim of the authors in the present investigation was to 

 answer the following questions : — How widely distributed is 

 cohenite? Are schreibersite and rhabdite definite compounds? 

 Has kamacite a constant composition ? Has tsenite always the 

 same physical and chemical properties? What is the composi- 

 tion of the jagged fragments so generally left undissolved after 

 treatment of meteoric irons with dilute hydrochloric acid? How 

 widely distributed are the transparent grains, as well as the 

 diamond, cliftonite, &c. ? 



Unfortunately, owing to the fact that the present joint inves- 

 tigation had to be brought to a somewhat premature conclusion, 

 a definite answer to all of these questions could not be given. 

 We may, however, expect soon to hear more on the points still 

 left undecided, as the promise is made that the gaps in the pre- 

 sent investigation shall be filled up as soon as possible. 



G. T. P. 



NO. I 151, VOL. 45] 



