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men from the Ethiopian region, Necator was almost exclusively by A. duodenale, while the only hookworm encountered. The search man of the Oriental and Ethiopian regions was not an exhaustive one. Leiper and others, parasitized exclusively or almost exclusively however, have recorded only Necator from this by Necator americanus. This finding in any region.

case suggests the possibility of the distribuI have not worked in Europe or northern tion of the two species of worms in distinctly Africa but Looss, Boycott and others report different zoologic as well as geographic regions the exclusive presence of A. duodenale in Eng- being due to there having been two primitive land, western Europe, Italy and Egypt, that races of man, each one originally parasitized is to say in the European moiety of the by a particular species of worm. Certain it is Holarctic region.

that N. americanus is found more exclusively The introduction of the negro, East Indian among black- and brown-skinned races, while and Mediterranean peoples into America has A. duodenale is found. exclusively or greatly obscured the picture here and research among predominates at the present time among Cauisolated and uncontaminated Indian tribes casian and Mongoloid stocks. has yet to be undertaken. This research will It may be that a Eurasiatic race of man, no doubt yield some interesting data, helpful possibly the Pithecanthropus of Trinil, Java, possibly in tracing the origin of the Amerind became split off and furnished the stock from populations; it may be possible to trace a which man of Oriental and Ethiopian regions relationship for them with Mongoloids from sprung. Proliopithecus emerging from HolHolarctic or from Oriental regions.

arctic Africa may have been not only the While there is a sharply marked out parent form of man, gibbon, chimpanzee, regional distribution of the worms in certain gorilla and the orang-outang, but he may have areas, in others time has brought about some harbored the parent form from which have overlapping of the two species.

arisen the different hookworm species found The absence of Necator from Europe indi- in the various species of anthropoids of tocates pretty positively that European soil has day. Possibly the ancestral tree of the not been contaminated by a Negroid race from primates can be revised after a study of the the Ethiopian region, that is Africa south of host relationships of their respective obligate the Sahara desert. The absence of A. duo- nematode parasites. At any rate we can say denale from secluded groups of mountain that it seems likely from the present distribupeople in the Oriental and in Ethiopian tion of A. duodenale and N. americanus as regions is explained in a similar way. In determined in surveys recently made of mid-Java and in a few coast and river towns selected groups that there were originally in Fiji, East Indians have brought in large of man parasitized exclusively by numbers of A. duodenale within historic A. duodenale and inhabiting the Holarctic times.

region, that is Europe, Asia, north of the The movements of negroes, Oriental and Oriental region and northern Africa; and Mediterranean peoples are modifying the that there were other races of man parasitized primitive worm-species-formula of non-migra- exclusively by N. americanus and inhabiting tory people, hence interpretations must be the Oriental region, that is the southern penmade from carefully selected surveys only. insulas of Asia and Indonesia or the Malay

It is held by some that man and his obligate Arch'ipelago; and also the Ethiopian region, parasites living in symbiosis have come along that is, Africa south of the Sahara Desert. through the ages together, that the relation- The subject is an enticing one to pursue ship has not been recently or casually ac- but further deductions should probably not be quired. If this be true we should expect to hazarded at this time by one who is merely find man parasitized always by the two ob- a peregrinating parasitologist. ligate forms and not to find man of the

SAMUEL T. DARLING Holarctic regions parasitized exclusively or INTERNATIONAL HEALTH BOARD

races

VEGETATION MAPPING

careful tests, and are presented not because of The value of accurate maps of native vege- any imagined novelty but because they may tation as a basis for very practical gen

prove useful to other workers under suitable eralizations can not be questioned. It is ob

conditions. vious that an essential condition for getting In original surveys of the forested states accurate maps of large areas is the existence

by government engineers the bearing trees at of precise maps of smaller component ones. section corners were often listed by species, At present very few precise local maps are while field notes of transects present an available, but it is to be hoped that botanists orderly panorama of forest types passed throughout the country will begin to supple through on each mile. The first Ohio surment the efforts of a few of their number who veys were generally done by trained woodsare doing map work of permanent and general men, and exhaustive field checks show that value.

their specific determinations of trees may be

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The workers who have contributed our pretty generally relied upon. Happily, too, various large area maps doubtless realize

there have been few serious errors in running better than any one else the impressionistic lines certainly nothing like the gross blunnature of their final product. In most cases ders of some of the surveyors of a later these men have done the utmost possible with day who worked in states farther west. When scanty and vague local data. There have one considers the genuine hardships and been, however, a few instances of buoyant dis- dangers unconsciously revealed by the field regard of the deadly principle of accumulation notes covering the Connecticut Western Re of error which ought not to have happened. serve (done before 1800), for example, the One author, mapping a fairly large area, excellence of the work is remarkable. secured local data from a source whose au- A means of utilizing these notes has been thority few would care to question and then worked out after some experiment, and comfrom his distant vantage point cut and bines economy of time with accuracy. A set trimmed until, speaking mildly, the accuracy of arbitrary generic symbols was devised of a considerable sector of his map was which could be logically grouped and readily seriously impaired.

memorized. Three typical series of symbols In preparing careful local maps of vegeta- are shown in the accompanying table. They tion the question of procedure varies greatly, consist of familiar units of penmanship and and is seldom an easy one. The two sources can be written without much effort, while of help outlined below have been put to rather their number can be increased to cover almost

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any problem without a great deal of inventiveness. Where necessary to indicate While stationed at Dorr Field, Arcadia, species an initial following the symbol does Florida, in 1918, the writer had excellent op

portunity to test the utility of the airplane Using these symbols the species of bearing as an aid in vegetation reconnaissance and trees at each section corner can be transcribed mapping. It goes without saying that experionto a sheet of cross section paper with one ence of this sort came as a by-product of centimeter or quarter inch squares. Where other duties which fairly filled the time. correspondence between original and modern There are two basic facts to emphasize in surveys is sufficiently close it is sometimes connection with airplane reconnaissance-first, convenient to transcribe directly upon

the tremendous increase in perspective made county road map or topographic sheet, as this possible, and second, the fact that each type gives a ready guide for field checking. With of vegetation preserves its distinctive shade an assistant reading locations and species it of color, and often a distinctive texture, so was found that an average county in Ohio long as it remains visible. could be transcribed in from thirty to forty- Granted that vegetation types are distincfive minutes, while one man working alone tive in shade and texture from considerable , could do the job in one or two hours.

altitudes, one has only to examine mosaic airIf, for publication or other reasons, a map

plane maps made with one of the excellent in colors is desired, distinctive colors can be automatic cameras now available to realize assigned to each series, and the various shades that this method can be just as useful for of these colors to the important species of the mapping vegetation as for locating gunpits respective series. The symbols may then be or analyzing topography. Because of the cost transcribed by means of properly colored dots

it is not likely that extensive photographic upon two millimeter cross section paper. maps will often be undertaken by individuals,

Finally and most important, it has been but pressure from individuals may be highly amply demonstrated that this network of

instrumental in getting organized agencies to specimen trees at one mile intervals affords a

undertake methodical mapping of this kind workable map of native vegetation, even

while native vegetation still remains. within an

For reconnaissance mapping, however, the area twenty miles square. One concrete instance of the usefulness of such a

airplane should be of great service to the

individual. The ecologist who is engaged in map within the Erie Basin of Ohio may be

studying a given region ought to pause to cited. The climax forest of glaciated Ohio is

balance the time he will spend in planning beech-maple, but there are considerable areas

and later in piecing together isolated field whose native vegetation is oak-hickory and

studies to get their broad interpretation also prairie. The map in question revealed

against the expense involved in taking two with great promptness a correlation whose

thirty-minute flights over the region. A minsignificance the reader may judge for him

imum of two flights has been suggested beself; the beech-maple covers what was upland

cause the first would permit intelligent planduring the recession of the postglacial lake,

ning of field studies while the second, taken the oak-hickory coincides with the great at the conclusion of these studies, would pershallow bays formed at various stages of

mit their proper synthesis and criticism. recession, and prairie (with occasional bog

Since expense is not the only objection that centers) marks clearly the deeper baymouths. is likely to arise, it may not be amiss to These facts of course become especially illu- mention that straight flying is uniformly a minating when taken in connection with the delightful experience and that notetaking or events of to-day, patent in and about San- even map sketching can be performed with dusky and Maumee bays.

ease inside of the cockpit.

The first fight in the Dorr Field region therefore can not give comparable results. suggested clearly the essential relations be- There is need for standardizing the fundatween pine flatwoods, palmetto scrub, and mentals of these methods by means of the prairie. These relations would have devel- preparation of a manual which will systemoped very slowly from field studies alone, as atize them while at the same time leaving to the forms of various areas were often mis- each investigator a free hand to perfect and leading when viewed from ground level, to complete them. These improvements would and significant differences of contour were be taken into consideration in future editions. matters of inches rather than feet. From the A circular will be sent to all naturalists air it seemed obvious that a key to the (zoologists, botanists, physiologists and chemsituation lay in the rainy season water levels. ists) and institutions interested and they will The prairies were observed to form a con- be requested to have it reprinted in the scientinuous system—the pathway of broad, shal- tific journals and distributed among those low rainy season drainage lines—the pal- interested in oceanography, as well as to metto scrub formed a fringing zone that solicit opinions, advice, criticism, and obsermight be occasionally flooded, while the pine vations of any kind. A committee was named flatwoods marked the true uplands. The truth to prepare the manual and to bring the plan of these first suggestions was conclusively before the meeting of the subsection of biofixed by subsequent field work and flights in logical oceanography in December, 1921. both rainy and dry seasons. Incidentally, Specialists who desire to participate in the combined ground and aerial studies forced commission for plankton studies are requested serious doubt of the true climax nature of so to inform the secretary. It is requested the pine flatwoods, which seemed in a number that all replies, printed matter, data concernof places to be suffering invasion by meso- ing capture, instruments, fabrics, nets, rephytic dicotyl forest. It was a matter of agents, preservation, and technical methods of some interest to learn later that this inference all kinds be addressed to the secretary. was borne out by unpublished data of two

AUSTIN H. CLARK other botanists working on different parts of the peninsula.

MADAME CURIE'S VISIT TO AMERICA PAUL B. SEARS

(From a Correspondent) UNIVERSITY OF NEBRASKA

MADAME MARIE CURIE, of Paris, the student

of radium, will visit this country in May as a SCIENTIFIC EVENTS

guest of the women of America. She will THE SYSTEMATIZATION OF PLANKTON bring with her her two daughters, the elder of INVESTIGATIONS

whom is also a scientist. THE following notice has just been received Madame Curie, internationally known for from Professor L. Joubin (Institut Océano- her studies on radium and its application as graphique, 195 Rue Saint-Jacques, Paris) the a remedial agent for cancer, is one of three secretary of the subsection of biological unusually gifted daughters of a Polish educaoceanography of the International Union of tor. One of her sisters is principal of an imBiological Sciences, International Research portant young women's school in Warsaw and Council.

the other is director of a large sanatorium in An international meeting of the delegates the Galician mountains. Madame Curie went of the national sections was held at Paris on to Paris from Warsaw as a young woman to January 27, 1921, under the presidency of study in the Sorbonne, and while in Paris marthe Prince of Monaco. At this meeting it ried the brilliant physicist and student of was agreed that the study of plankton is not radium, Professor Pierre Curie, who met a progressing as well as might be desired, be- tragic death by accident in a Paris street in cause the methods of investigation vary and 1906. She is now a teacher in the Sorbonne and an investigator in the Curie Radium In- been secured. A rate of one and one half fare stitute, to the support of which she has devoted for the round trip journey under the certifithe money received by her from the Nobel cate plan has been granted. This is good Prize award, as also the money received from from all parts of the United States, except other awards.

New England, and west of Utah, the New While in America Madame Curie will be England and Transcontinental Association given honorary degrees by several American having declined to give rates. The Rochester universities and a medal by a leading scien- hotel is the headquarters. tific society. In addition a group of women in The preliminary program is as follows: New York and Washington are trying to raise funds sufficient to purchase and present to her,

Monday, April 25 as a gift from the women of America, a gram 4.00 P.M.-Council meeting, Rochester Club. of radium for use in her experimental work 6.30 P.M.-Dinner to the council at the Rochester in the Curie Radium Institute. When asked

Club, recently in Paris:“What would you most pre

Tuesday, April 26 fer to have in the world?” Madame Curie

10.00 A.M.-General meeting, Chamber of Compromptly replied “A gram of radium under

merce. my own control.”.

Address of welcome, Hiram Edgerton, She has never possessed such an amount of

and W. Roy McCanne, president of radium for her independent use, nor can she

the Rochester Chamber of Com. ever afford from her own means to buy it.

merce. She lives on the modest stipend received by

Response, Edgar F. Smith, president her for her teaching and research work in the

of the American Chemical Society. Sorbonne and does not care for more money

General addresses, by Senator James except to put it into the equipment and sup

W. Wadsworth, Jr., and Congressport of her laboratory.

man Nicholas Longworth. If the beautiful idea of making to Madame

2.00 P.M.-General meeting, Convention Hall.

Papers, by E. C. Franklin, C. E. K. Curie, on the occasion of her visit here, the

Mees and others. gift of a gram of radium in recognition of her

6.30 P.M.-College and Fraternity dinners. achievements in he interests of science and humanity, can be realized, it will be the most

Wednesday, April 27 fitting and appreciated tribute that can be 9.00 A.M.-Divisional meetings, Mechanics Insti

tute. paid her. The radium will cost about $100,000 and

1.30 P.M.—Divisional meetings, Mechanics Insti

tute. contributions, even small sums, are earnestly

8.00 P.M.-Public address, speaker to be ansolicited. If sent to Mrs. Vernon Kellogg,

nounced. 1701 Massachusetts Avenue, Washington, D. C., they will be receipted and properly ac

Thursday, April 28 counted for.

9.00 A.M.—Divisional meetings, Mechanics Insti

tute. THE ROCHESTER MEETING OF THE AMERICAN

Sigma Xi Luncheon-Hotel Rochester. CHEMICAL SOCIETY

2.00 P.M.—Divisional meetings, Mechanics Insti. The spring meeting of the American Chem

tute. ical Society will be held with the Rochester

3.00 P.M.—Meeting of chairman and secretaries

of local sections, Section, Tuesday, April 26, to Fliday, April

7.00 P.M.-Good-Fellowship meeting, Bausch and 29, inclusive. A large and successful meeting

Lomb's Dining Hall. is assured as many thousand members of the society are within a night's journey of

Friday, April 29 Rochester and reduced railroad rates have 8.30 A.M.-Excursions.

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