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260°. There is a scale which might have been is no longer tenable; and there is not sufficient advantageously used here, namely the Kel- emphasis laid on the fact that the high rotavin-Kilograde scale. True, few are as yet tive values are hypothetical, not real so far as familiar with it; but the colors should always mobile air is involved. be in advance of the line, not abreast nor yet Chapter XI., Winds Adverse to behind. In an up-to-date scientific book we Aviation,” explains the so-called “holes in have the right to expect leadership rather the air," “ bumps," “ dunts,” etc. There is not than tolerance.

a mathematical symbol in the whole chapter. The airman has got to forget the unscien- The different phenomena are explained in tific, arbitrary scales of his fathers; and stop straightforward, simple language. However, using inches, minus signs, etc. His range of there is much yet to be learned in connection

emperature is from summer day surface with favorable and adverse conditions; and values to winter sub-polar readings near the we await some Maury who will do with the stratosphere; and old-fashioned methods are logs of airships what the old Commodore did inadequate.

with the logs of the clippers of his day. Pressures are generally given in this book Chapter XIV. contains many photographs in millimeters of mercury with occasional of cloud forms, but neither here nor in the lapses into inches. In a treatise dated 1920, first chapter where many instruments are one might look for pressure values through- given, is mention made of a nephoscope. Fair out in units of force, that is, dynes or kilo- credit for cloud work done at Blue Hill Obdynes per square centimeter.

servatory is not given; nor is mention made In the chapter on “Atmospheric Circula- of Professor Bigelow's International Cloud tion” which is well put, and more clearly Report. explains the mechanics of deflection than most Chapter XV., on The Thunderstorm" has other text-books, it is demonstrated that in 105 pages, and yet is not included in Part II., the case of a wind with a velocity of 22 meters dealing with Atmospheric Electricity and per second, there will be a modification of Auroras, which has only 18 pages. velocity, depending upon whether the wind is Part III., on “Atmospheric Optics," has 129 blowing east or west; that is, a given mass pages and is based largely on the well-known weighs less going east than going west. A Pernter-Exner “Meteorologische Optik" and note might have been added giving results of Mascart's “ Traité d'Optique.” recent gravity determinations at sea on fast- Part IV., 74 pages, deals with factors of moving (22-knot) destroyers (25-mile-per-hour climatic control, that is, in the author's words, vessels); in which it was definitely ascertained a discussion of the physics of climate and not that the barometric pressure changed 0.1 of its geographic distribution. The chief kilobar (0.075 mm.) when the course was factors considered are latitude, brightness of reversed. Going east with the earth the the moon and planets, solar constant, solar centripetal force is greater than when steam- distance, obliquity of ecliptic, perihelion phase, ing west. All this is of importance in con- extent and composition of the atmosphere, nection with fast-moving airships.1

vulcanism, sun spots, land elevation, land and The discussion of change of velocity with water distribution, atmospheric circulation, latitude, deflective effect of the earth’s rota- ocean circulation, and surface covering. tion, relative values of centrifugal and rota- Elaborate tables of gradient wind velocities tional components, and gradient winds, is are given in the appendix. We notice a few thorough and well expressed. Of course, the minor typographical errors. On page 136, explanation of friction acting as the effective latitude 10°, the change of direction is 2o.61 damping factor against high rotational winds not 261, and the heading needs revising on

1 See SCIENCE, February 6, 1920; also January page 162, m.m. should be mm.; on page 221, 9, 1920.

figure 31 should be 32; and on page 227, figure

a

57, the lengend should give the elevation of the 4. The application of names is determined station. ALEXANDER MCADIE by means of nomenclatural types.

Note.-A generic name is always so applied REPORT OF THE COMMITTEE ON

as to include its type species; a specific name NOMENCLATURE OF THE

is always so applied as to include its type BOTANICAL SOCIETY

specimen. OF AMERICA

Rules and Recommendations Ar the Baltimore meeting of the Botanical

Section 1. Publication of Names Society of America (1918), the Committee in

Article 1. A specific name is published Generic Types presented a set of rules for fix

when it has been printed and distributed with ing the types of genera. The report was pub

a description, or with a reference to a prelished in SCIENCE (49: 333–336. 1919). At the

viously published description. same meeting the committee was enlarged to

Note.-A recognizable figure may be the nine members and made a standing committee

equivalent of a description in the literature on botanical nomenclature, with authority to

of paleobotany and diatoms. prepare a code of nomenclature. The stand

(a) In the transfer of a species from one ing committee consists of LeRoy Abrams,

genus to another, the original specific name N. L. Britton, E. A. Burtt, A. W. Evans, J.

is retained, unless the resulting binomial has M. Greenman, A. S. Hitchcock, M. A. Howe,

been previously published. C. L. Shear and Witmer Stone. The actual

Recommendations: Botanists will do well, work of elaborating a code was done chiefly

in publishing: by a subcommittee consisting of J. C. Arthur,

1. In describing parasitic fungi to indicate J. H. Barnhart, R. S. Breed, N. L. Britton,

the host and to designate the name of the O. F. Cook, F. V. Coville, A. W. Evans, B.

host by its scientific Latin name. Fink, A. S. Hitchcock, M. A. Howe, F. H.

2. To give the etymology of all new generic Knowlton, P. L. Ricker, C. L. Shear and H. C. Skeels. The following code was presented

Article 2. by the committee:

A generic name is published when it has been printed and distributed

(a) With a generic or specific description (or a recognizable figure, see Art. 1, note) and

a binomial specific name, 1. The primary object of formal nomen

(6) With a generic and specific name and clature in systematic biology is to secure

the citation of a previously published descripstability, uniformity, and convenience in the

tion, designation of plants and animals. 2. Botanical nomenclature is treated

(c) With a definite reference to at least beginning with the general application of

one previously published binomial. binomial names to plants (Linnæus' “Species

Note a.-A name is not published by its Plantarum," 1753).

citation in synonymy, nor by incidental men3. Priority of publication is a fundamental

tion. Such a name may be taken up but not principle of botanical nomenclature. Two

to replace one already properly published.

Note b.Of names published in the same groups of the same category can not bear the

work and at the same time, those having preNote a.—This principle applies primarily to

cedence of position are to be regarded as

having priority. genera and species.

Note 6.—Previous use of a name in zoology Recommendation: Botanists will do well, in does not preclude its use in botany; but the publishing, to give the etymology of specific proposal of such a name should be avoided. names when their meaning is not obvious.

names.

A TYPE-BASIS CODE OF BOTANICAL NOMENCLATURE

PRINCIPLES

as

same name.

the type.

Section 2. Application of Names

6. If an author, in publishing a new species, Article 3. The nomenclatural type of a

gives a description of his own, this takes prespecies is the specimen or the most important cedence over synonymy or cited descriptions, of the specimens upon which its original pub

in determining the type specimen. lished description was based.

Article 4. The nomenclatural type species (a) If only one specimen is cited, that is

of a genus is the species or one of the species

included when the genus was originally (6) If one specimen is designated as the published. type, that specimen shall be so accepted, un- (a) If a genus includes but one species less an error can be demonstrated.

when originally published this species is the (c) A species transferred without change type. of name from one genus to another retains (6) When more than one species is inthe original type even though the description cluded in the original publication of the under the new genus was drawn from a differ

genus, the type is determined by the followent species.

ing rules: (These rules are Articles 3 to 6 of (d) The publication of a new specific name the Report of the Committee on Generic as an avowed substitute for an earlier one does Types published in SCIENCE, N. S., 49: 334not change the type of the species.

336, 1919.) (e) When more than one specimen was Recommendations: In the future it is originally cited and no type was designated recommended that authors of generic names the type should be selected in accordance with definitely designate type species; and that in the following:

the selection of types of genera previously 1. The type specimen interprets the de

published, but of which the type would not be scription and fixes the application of the indicated by the preceding rules, the followname, hence, primarily the description con- ing points be taken into consideration. (This trols the selection of the type.

includes Article 7, a to g, of the Report on 2. The type may be indicated by the specific Generic Types published in SCIENCE, loc. cit.). name, this being sometimes derived from the collector, locality, or host.

Section 3. Rejection of Names 3. If one specimen is figured in connection Article 5. A name is rejected with the original description this may usually (a) When preoccupied (homonym). be regarded as the type.

1. A specific name is a homonym when it 4. Specimens that are mentioned by the has been published for another species under author as being exceptional or unusual, or the same generic name. those which definitely disagree with the de- 2. A generic name is a homonym when scription (provided others agree) may usually previously published for another genus. be excluded from consideration in selecting

3. Similar names to be treated the type.

homonyms only when they are mere varia5. An examination of the actual sheets of tions in the spelling of the same word; or in specimens studied by the author may aid in the case of specific names, when they differ determining or selecting the type. He may only in adjective or genitive termination. have written the name or left notes or draw- (b) When there is an older valid name ings upon one of the sheets.

based on another member of the same group Note.-Specimens known to have been re- (metonym). ceived by the author subsequent to the study (c) When there is an older valid name resulting in the original publication should based on the same type (typonym). be excluded from consideration.

(d) When it has not been effectively pub

are

as

lished according to the provisions of Section 1 of these rules (hyponym).

Article 6. There may be exceptions to the application of the principles and rules of this code in cases where a rigid application would lead to great confusion. Such exceptions become valid when approved by the Nomenclature Commission.

the form of recommendations, the commission meantime perfecting rules and formulating methods of procedure. International rules of nomenclature, including rules for the retroactive fixation of generic types and including a provision for exceptions, together with an International Commission to validate names (generic types and nomina conservanda) would go far toward giving to botany a stable and uniform nomenclature.

A. S. HITCHCOCK,

Chairman BUREAU OF PLANT INDUSTRY,

WASHINGTON, D. C.

Nomenclature Commission A code of nomenclature should secure uniformity, definiteness and stability in the application of names. If proposed rules result in the change of well-established names of economic plants botanists will hesitate to apply them uniformly. All contingencies can not be foreseen and experience has shown that the rigid application of any set of rules results in a few cases of greatly confused nomenclature. The committee has recognized this and hence has introduced an article permitting exceptions. The committee also recognized that to secure uniformity and definiteness the exceptions should in some way be validated. The most convenient and practical validation would be through a permanent judicial body created for the purpose. As the proposed code invites international support, the judicial body should be an international commission. The committee felt that much could be done to pave the way for future international action by appointing a national commission and therefore tentatively submitted a plan for the creation of such a body. This temporary Nomenclature Commission was to consist of nine members, one nominated by the Society of American Bacteriologists, one nominated by the American Phytopathological Society, three elected by the Botanical Society of America, and four elected by the Committee on Nomenclature of the Botanical Society. The details concerning elections and reappointments are here omitted.

The chairman will add that since a subsequent international commission would feel restricted by the decisions of a national body, it might be well to have these decisions take

SPECIAL ARTICLES A FISH, WITH A LUMINOUS ORGAN, DESIGNED FOR THE GROWTH OF LUMINOUS BACTERIA

It has been known for many years that luminous bacteria are abundant in the sea and will grow readily upon dead fish or other marine organisms. It has been reported that at times luminous bacteria may infect living forms, such as sand fleas. A malady is produced, which is finally fatal but which, during its course, causes the animal to luminesce like a true luminous form. Pierantoni2 has suggested that the light of many luminous organisms is due to symbiotic bacteria living in the cells of the luminous organisms. He claims to have grown the bacteria artificially in the case of certain squid.

While I feel convinced that this is not the case in all luminous animals I have recently had an opportunitys of studying two forms which do appear to utilize bacterial light. These are the marine fishes, Photoplepharon and Anomalops, found in the Banda Islands of the Dutch East Indian Archipelago. They have been known to be luminous since 1897, but the organ was first studied histologically by Stechet and found to be made up of a series of columnar gland tubes, a number of which

1 Giard and Billet, C. R. Soc. Biol., I., 593, 1889. 2 Scientia, XXIII., 43, 1918.

3 A study made under the auspices of the Department of Marine Biology, Carnegie Institution of Washington.

4 Zeit. Wiss. Zool., XCII., 349, 1909.

seen.

unite to a reservoir which opens to the sea water by a pore. The pores are quite regularly arranged over the outer surface of the organ from which the light emerges.

Despite the general appearance of an organ of external secretion, no luminous material is excreted to the sea water by the living fish. This rather unusual fact has, I believe, its meaning. If the organ is tested in sea water and examined under the microscope, innumerable motile rod-shaped bacteria, sometimes forming spirilla-like chains, can be

Smears of the organ, which I obtained in Banda, have been very kindly stained for me by Professor Dahlgren, of Princeton University, and show the bacteria nicely.

In chemical respects an emulsion of the organ behaves just as an emulsion of luminous bacteria and differs in one or another way from extracts of other luminous animals. These various characteristics may be summarized as follows:

1. The light organ is extraordinarily well supplied with blood vessels and the emulsion fully as sensitive to lack of oxygen as are luminous bacteria. Light ceases very quickly in absence of oxygen.

2. If dried, the organ will give only a faint light when again moistened with water. This is characteristic of luminous bacteria. The luminous organs of most other forms can be dried without much loss of photogenic power. 3. Luciferin and luciferase can

not be demonstrated.

4. The light is extinguished without a preliminary flash by fresh water and other cytolytic (bacteriolytic) agents. 5. Sodium fluoride of 1 to 0.5

per

cent. concentration extinguishes readily the light of an emulsion of the gland.

6. Potassium cyanide has an inhibitive effect on light production in about the same concentration as with luminous bacteria.

To these observations must be added the very suggestive fact that the light of Photoplepharon and Anomalops continues night and day without ceasing and quite independently of stimulation. This is a characteristic of luminous bacteria and fungi alone among

organisms, and very strongly suggests that the light is actually due to symbiotic luminous bacteria. The organ becomes, then, an incubator for the growth and nourishment of these forms and we may perhaps look upon the pores mentioned above as a means of exit for dead bacteria. Otherwise their existance would be inexplicable in an organ which certainly does not

not produce an external secretion.

Actual proof that the bacteria found in the organ are luminous can only come when these are grown artificially. My attempts in this direction have failed. Good growths of bacteria were obtained on pepton-agar but they produced no light. One might expect that a symbiotic form would require rather definite food materials to produce light and it is, perhaps, not surprising that culture experiments have failed. We have Giard and Billet's experience with the form infecting sand fleas. This could be grown artificially but only produced light when infecting the sand fleas themselves. Certainly, the ocular and chemical evidence, if not the cultural evidence, supports the view that the light of these living fish is bacterial in origin. A complete account of the fish will appear shortly in the Carnegie Institution Publications.

E. NEWTON HARVEY PRINCETON UNIVERSITY,

March 1, 1921

THE AMERICAN ASSOCIATION FOR

THE ADVANCEMENT OF SCIENCE SECTION L-HISTORY OF SCIENCE SESSIONS

The growing and widespread interest in the history of science, in this country, was very evident during the Convocation Week (December 27-January 1), when two learned national organizations held meetings in Washington, D. C., and Chicago. Each of these organizations held sessions upon the history of science,

During the same week in 1919, The American Historical Association inaugurated the movement by holding at its Cleveland meeting, a most interesting and successful conference. This same asso

1 SCIENCE, N. S., Vol. LI., pp. 193–194, February 20, 1920.

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