20-23 June

Geodynamics

Mexico City, with its 9 million in-habitants and its burgeoning scientificfacilities, will be host to the first sym-posium on geodynamics to be held inthis continent, 20-23 June. The 31/2-day event will include invited papers byabout 25 scientists from the UnitedStates, Latin America, and other coun-tries, followed by round-table discus-sions.Some of the problems to be dis-

cussed are: tectonics of the Gulf of

Mexico, Yucatan, and Guatemala; ori-gin and age relations across the Mexi-can Volcanic Belt; mechanism of sub-duction in the Middle America Trenchfrom studies of the aftershock sequenceof the Colima earthquake of 30 Jan-uary 1973; comparative studies of theevolution of the west coast of NorthAmerica; and reports on recent geo-physical cruises in the areas of theNasca and Cocos plates. A session on"mechanisms of sea-floor spreading"

and a joint session with the earthquakeengineering symposium on earthquakehazard in relation to the Managuaearthquake, are also planned.

This symposium is cosponsored byAAAS, the Consejo Nacional de Cien-cia y Tecnologia of Mexico, and theInter-Union Commission on Geo-dynamics. The arrangers are C. L.Drake (Dartmouth University) and C.Lomnitz (University of Mexico). Afield trip to the volcanoes near MexicoCity will close the symposium.

C. LOMNITZInstituto de Geofisica, UniversidadNacional Autonoma de Mexico

21-23 June

Volcanism in Mexico and Centrad Anerica

Active volcanoes are major geologicfeatures in Mexico and Central Amer-ica; they create both hazards and bless-ings for the region. Forecasting erup-tions has long been a goal of volcanol-ogy and, although useful predictions arestill only a visionary hope, some prog-ress is being made.Many of the volcanic eruptions in

Mexico and Central America are highlyexplosive. The emitted gases and ashare one of the atmosphere's major nat-ural pollutants, and they can be usedas a meter stick against which man'satmospheric pollutants can be com-pared. Geothermal steam reservoirs areproving to be an important source ofenergy. In most cases these naturalsteam occurrences are closely relatedto volcanic activity.The symposium (21-23 June) fo-

cuses on these topics of volcanismwhich are most relevant to mankind:forecasting volcanic eruptions, explo-sive volcanism, and geothermal power.

Five speakers will discuss the cur-rent status of predicting volcanic erup-tions. Several approaches (includinghistoric activity pattems, seismic moni-toring, small ground surface move-

ments, and changes in temperature andgas emissions) show considerable prom-

ise, but no single technique at present

Arenal Volcano, central Costa Rica,erupted violently in the summer of 1968after about 500 years of repose. The abovephoto shows lava flow still being emitted,4 November 1971, from the lower explo-sion crater on the west flank of the vol-cano. [Courtesy Instituto Geogrifico, CostaRica]16 MARCH 1973

is a reliable indicator of forthcomingeruptions.The volcanoes of Mexico and Cen-

tral America are much more explosivethan those in Hawaii. Because of thelong intervals between, and the dangerduring eruptions, the mechanics of ex-plosive volcanic eruptions are not as

thoroughly studied and, therefore, lesswell understood than the eruptions in

Hawaii. Five speakers will discuss theproducts and mechanisms of explosivevolcanism, and motion picture films ofthe recent eruption of Pacaya Volcanoin Guatemala will be shown.

Geothermal power resources are cur-rently of great interest in Mexico andCentral America. Five speakers willdiscuss the recent developments andfuture prospects of geothermal powerin this region.

R. W. DEcKERDartmouth College,Hanover, New Hampshire

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FORTHCOMING EVENTS

April

/6-18. Anglo-American Ccnf. on DrugAbuse, jcintly by Royal Soc. of Medicineand Roy,al Soc. of Medicine FoundationInc., I ondon, England. (Conf. Office, RoyalSoc. cf Medicine, I Wimpole St., Lon-don, WlM 8AE)

16-18. Liquid State-Van der WaalsCentenary, Kent, England. (Meetings Of-ficer, Inst. of Physics, 47 Belgrave Sq..London SWIX 8QX England)

16-18. Nonlinear Elasticity, Madison,Wis. (G. G. Moran, Mathematics Research

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16-20. American Soc. for ExperimentalPathology, Atlantic City, N.J. (G. B.Mider, ASEP, 9650 Rockville Pike, Be-thesda, Md. 20014)

16-20. American Geophysical Union,54th annual, Washington, D.C. (A. F.Spilhaus, Jr., AGU, 1707 L St., NW,Washington, D.C. 20036)

16-20. American Assoc. of Immunol-ogists, Atlantic City, N.J. (H. Metzger,AA[, 9650 Rockville Pike, Bethesda, Md.20014)

16-20. American Inst. of Nutrition,Atlantic City, N.J. (AIN, 9650 RockvillePike, Bethesda, Md. 20014)

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16-20. American Soc. for Pharmacologyand Experimental Therapeutics, AtlanticCity, N.J. (E. B. Cook, ASPET, 9650Rockville Pike, Bethesda, Md. 20014)

18-20. Great Lakes Research, 16thconf., Intern. Assoc. for Great LakesResearch, Columbus, Ohio. (C. E. Herden-dorf, College of Biological Sciences, OhioState Univ., Columbus 43210)

19-20. Symposium on Controlled Re-lease of Biologically Active Agents.Birmingham, Ala. (A. C. Tanquary,Southern Research Inst., 2000 Ninth Ave.S., Birmingham 35205)

19-21. Southern Soc. for Philosophyand Psychology, Knoxville, Tenn. (M.Loeb, Dept. of Psychology, Univ. ofLouisville, Louisville, Ky.)20-2 1. Illinois State Acad. of Science,

Urbana. (N. R. Brewer, ISAS, 5757 S.Drexel Ave., Chicago)

22-26. American Radium Soc., Colo-rado Springs, Colo. (F. N. Rutledge, 4828Caroline St., Houston, Tex. 77004)

22-27. Council for Exceptional Chil-dren. 51st annual intern., Dallas, Tex. (P.W. Stavros, CEC, 1411 S. Jefferson DavisHwy., Arlington, Va. 22202)

23-25. Instrument Soc. of America,19th analysis instrumentation symp., 14thchemical and petroleum instrumentationsymp., Process Measurement and Con-trol Div. symp., St. Louis, Mo. (J. L.Kern, Monsanto Co., 800 N. LindberghSt., St. Louis 63166)

23-28. American Acad. of Neurology,Boston, Mass. (S. A. Nelson, AAN, 4005W. 65 St., Minneapolis, Minn. 55435)

23-30. American Soc. for ClinicalInvestigation, Atlantic City, N.J. (P.Calabresi, Roger Williams General Hos-pital, Providence, R.I. 02908)

24-25. Association for Population/Fam-ily Planning Libraries and InformationCenters. 6th natl. conf., New Orleans, La.(R. Versteeg, APLIC, c/o Carolina Popu-lation Center Library, University Sq.,Chapel Hill, N.C. 27514)

24-27. International Magnetics Conf.,Magnetic Soc. of the Inst. of Electricaland Electronics Engineers, Washington,D.C. (D. H. Looney, Bell Labs., Whip-pany Rd., Whippany, N.J. 07981)25-26. American Geriatrics Soc., Beverly

Hills, Calif. (E. Henderson, 10 ColumbusCircle, New York 10019)

25-27. Nondestructive Evaluation, 9thsymp., Southwest Research Inst. and SouthTexas Section, American Soc. for Non-destructive Testing, Inc., San Antonio.(G. Matzkanin, SRI, P.O. Drawer 28510,San Antonio 78284)

25-27. The Ocean, Nuclear Energy, andMan, American Nuclear Soc. and MarineTechnology Soc., Palmn Beach Shores(Singer Island), Fla. (M. J. Ohanian, Dept.of Nuclear Engineering, Univ. of Florida.Gainesville 32601)

25-28. International CommunicationAssoc., Montreal, P.Q., Canada. (M. Z.Sincoff, Center for Communication Studies,Ohio Univ., Athens 45201)

25-28. National Council of Teachersof Mathematics, Houston, Tex. (J. D.Gates, NCTM, 1201 16th St., NW, Wash-ington, D.C. 20005)

26. Sigma Pi Sigma, Washington, D.C.(D. W. J. Shea, State Univ. of New York,Stony Brook 11790)

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26-27. Scanning Electron MicroscopeSymp., 6th annual, Chicago, Ill. (0. Johari,IIT Research Inst., 10 W. 35 St., Chicago60616)

26-28. Louisiana Acad. of Sciences,Monroe. (B. F. Dowden, Dept. of Biologi-cal Sciences, Louisiana State Univ., Shreve-port 71105)26-28. Ohio Acad. of Science, Cleveland.

(J. H. Melvin, OAS, 445 King Ave.,Columbus 43201)

26-28. Population Assoc. of America,New Orleans, La. (J. W. Brackett, PAA,P.O. Box 14182, Benjamin Franklin Sta.,Washington, D.C. 20044)

27-28. Georgia Acad. of Science.Atlanta. (E. A. Stanley, Dept. of Geology,Univ. of Georgia, Athens 30601)

27-28. Iowa Acad. of Science, Grinnell.(R. W. Hanson, Dept. of Chemistry, Univ.of Northern Iowa, Cedar Falls 50613)

27-28. Missouri Acad. of Science,Columbia. (R. G. Combs, 206 ElectricalEngineering Bldg., Univ. of Missouri,Columbia 65201)

27-28. North Carolina Acad. of Science,Charlotte. (J. A. Yarbrough, Dept. ofBiology, Meredith College, Raleigh 27602)

27-28. North Dakota Acad. of Science,Grand Forks, N.D. (A. W. Johnson, Uni-versity Station, P.O. Box 8123, Univ. ofNorth Dakota, Grand Forks 58201)

27-28. American Assoc. of UniversityProfessors, St. Louis, Mo. (B. H. Davis,AAUP, Suite 500, 1 Dupont Circle, NW,Washington, D.C. 20036)

27-28. Wisconsin Acad. of Sciences,Arts and Letters, Prairie duL Chien. (J. R.Batt, WASAL, 5001 University Ave., Madi-son 53705)

28. Society for Investigative Dermatol-ogy, Atlantic City, N.J. (J. S. Strauss,Boston Univ. Medical Center, 80 E. Con-cord St., Boston, Mass. 02118)

28. Societal Problems of Water Re-sources, 2nd annual symp., Illinois EarthScience Assoc., Chicago. (M. Qutub,Northeastern Illinois Univ., Bryn Mawr atSt. Louis Ave., Chicago 60625)

28-29. Montana Acad. of Sciences, Dil-lon. (R. E. Juday, Dept. of Chemistry,Univ. of Montana, Missoula 59801)

28-30. International Symp. on the Ge-netics of Cyanophytes, Pittsburgh, Pa. (E.Raizen, Dept. of Biological Sciences, Du-quesne Univ., Pittsburgh 15219)

29-30. Congress on EnvironmentalHealth, American Medical Assoc., Chica-go, 111. (F. W. Barton, AMA, 535 N. Dear-born St., Chicago 60610)

29-1. Classification Soc., North Ameri-can Branch, 4th annual, Atlanta, Ga.(F. J. Rohlf, Dept. of Biology, State Univ.of New York, Stony Brook 11790)

29-2. Off-Shore Technology, Inst. ofElectrical and Electronics Engineers, Hous-ton, Tex. (Technical Activities Bd., 345 E.47 St., New York 10017)

29-3. American Ceramic Soc., Inc.,Cincinnati, Ohio. (F. P. Reid, ACSI, 65Ceramic Dr., Columbus 43214)

29-3. American Oil Chemists Soc., NewOrleans, La. (J. Lyon, AOCS, 508 S. 6 St.,Champaign, III. 61820)

30-12. Lindau Psychotherapy Weeks,Assoc. for Psychotherapeutic Training,Lindau, Germany. (H. Stolze, D-8 Mun-chen 81, Adalbert-Stifter-Strasse 31)

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1-2. Electron Device Techniques Conf.,Inst. of Electrical and Electronics Engi-neers. New York, N.Y. (D. Slater, Ad-visory Grouip on Electron Devices, 9thFloor-, 201 Va.rick St., New York 10014)

1-3. Industrial WNaste, 28th annual conf.,West l afayette, Ind. (D. W. Hawkins.Room 308, Civil Engineer-ing Bldg., Pur-due Univ.. West Lafayette 47907)

1-4. Virginiia Acad. of Science, Wil-liarmshurgT. (R. C. Berry, 5907 BrookfieldRd., Richmond, Va. 23227)

2-4. International Conf. on SurgicalCare, Roy'al College of SuLrgeons, Dublin.Ireland. (H. O'Flanagan, Irish MedicalAssoc., 10 Fitzwilliam P1., Dublin 2)

2-5. N1idwestern Assoc. of ForensicScientists. Larnsitg, Nlich. (R. E. Bisbing,Div. of Crime Detection, Michigan Dept.of P1,blic Health. 3500 N. Logan St.,1 ansing 48914)

2-6. Protides of Biological Fluids, 21stcolloquriuLm, Brutgge, Belgium. (Colloqui-um on Protides of the Biological Fluids,Simon Stevin InstitLuut, JerUsalemstraat34. B(-8000 Briro-e)

3-4. National Information Retrieval Col-loCl riu m.l)1th a rinial, PhilaIdelphia. Pa. (NI.NLrssbaLIm, Comput-amation, 2955 Kensing-ton Ave., Philadelphia 19134)

3-5. Society for American Archaeology,San Francisco, Calif. (R. E. W. Adams,Univ. of Texas, SUrite 250, 4242 PiedrasDr., San Antonio 78228)

3-5. American Assoc. for the Historyof Mtedicine, Cinicinnati, Ohio. (G. Miller,Howard Dittrick MNrseuLm of HistoricalNledicine, 11,000 FLclid Ave., Cleveland,Ohio 44106)

3-5. Fastern Psychological Assoc.,Washington. D.C. (NI. Benimoff, Dept. ofPsychology, Glassboro State College,Glassboro, N.J. 08028)

3-6. Christian Mledical Soc., Dallas,Tex. (H. W. Robinson, 3909 Swiss Ave.,Dallas 75214)

3-6. Association of Clinical Scientists,Tampa, Fla. (F. W. Sunderman, Jr., Univ.of ConnecticLrt, School of Medicine, BoxG, Farmington 06032)

3-0. National Assoc. of Social Wl'orkers,Atlanta, Ga. (C. A. Alexander, NASW,600 SoLlthern Bldg., 15th and H Sts., NW,Washington, D.C. 20005)

3-7. American Psychoanalytic Assoc.,HonolIlLu, Hawaii. (S. Goodman, 3021Telegraph Ave., Berkeley, Calif. 94705)

3-7. Association for Research in Visionand Ophthalmology, Sarasota, Fla. (R. D.Reinecke, Albany Medical College, Al-bany, N.Y. 12208)

4-5. Nliinnesota Acad. of Science,Northfield. (NI. 1. Harrigan, MAS, 310038th Ave., S., Nlinneapolis, Minn. 55406)

4-5. North Dakota Acad. of Science,Grand Forks. (B. G. Gustafson, Div. ofContintring EduLcation, Univ. of NorthDakota, Grand Forks 58201)

4-6. American College of Apothecaries,St. I oUris, NMo. (D. C. Huffman, Jr., 5291Rock Ridge Rd., Nlemlphis, Tenn. 38128)

4-6. Drosophila Research Conf., DeKalb. Ill. (S. NMittler. Dept. of BiologicalScience, Northern Illinois Univ., De Kalb60115)

4-6. American Acad. of Psychoanalysis,Honolulu. Hawaii. (J. Barnett, AAP, 40

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Gramercy Park North, New York 10024)6-11. American Soc. for Microbiology,

Miami Beach, Fla. (R. W. Sarber, ASM,1913 1 St., NW, WVashington, D.C.20006)

7-9. Rocky Mountain BioengineeringSymp., 10th annual, Boulder, Colo. (N.B. Kindig, Dept. of Electrical Engineer-ing, Univ. of Colorado, Boulder 80302)

7-9. Society of Economic Paleontolo-gists and Mineralogists, Anaheim, Calif.(Mrs. R. Tener, SEPM, Box 979, Tulsa,Okla. 74101)

7-10. Aerospace Medical Assoc., LasVegas, Nev. (M. H. Goodwin, AMA,Washington National Airport, Washing-ton, D.C. 20001)

7-11. Society of Manufacturing En-gineers, Detroit, Mich. (R. W. Taylor,SME, 20501 Ford Rd., Dearborn, Mich.48128)

7-11. Society of Plastics Engineers,Montreal, P.Q., Canada. (C. C. Campbell,SPE, 656 WV. Putnam Ave., Greenwich,Conn. 06830)

8-9. Fluvial Processes and Sedimenta-tion, 9th Canadian Hydrology Symp.,Edmonton, Alta., Canada. (C. R. Neill,Research Council of Alberta, 303 Civil-Electrical Engineering Bldg., Univ. ofAlberta, Edmonton T6G 2E1)

9-11. Operations Research Soc. ofAmerica, Mlilwaukee, Wis. (J. R. Bor-sting, Dept. of Operations Research andAdministrative Science, Naval Postgrad-tate School, Monterey, Calif. 93940)

9-11. Midwestern Psychological Assoc.,

Chicago, Ill. (W. F. Hill, Dept. of Psy-chology, Northwestern Univ., Evanston,Ill. 60201)

9-11. International Symp. on Throm-bosis and (lie Molecular Biology of theI'latelet amid Otlier Interacting Cells,Chicago, Ill. (F. h. Booyse, Dept. ofBiochemistry, Ruish Mledical College, 1753W. Congress Pkwy., Chicago 60612)

9-12. Society for Technical Communi-cation, Houston, Tex. (C. T. Youngblood,STC, Suite 421, 1010 Vermont Ave., NW,Washington, D.C. 20005)

10-11. Polymer and Fiber Microscopy,12th symp., Textile Research Inst., Ra-leigh, N.C. (D. C. Felty, Chemstrand Re-search Center, Research Triangle Park,DLurham, N.C. 27702)

11-12. American Assoc. of ClinicalUrologists, New York, N.Y. (R. B. Car-son, AACU, 708 E. Broward Blvd., FortLauderdale, Fla. 33301)

13-17. Radiation Research Soc., St.Louis, Mo. (R. J. Bturk, Jr., RRS, 421139th St., NW, Washington, D.C. 20016)

13-18. Electrochemical Soc., Chicago,Ill. (E. G. Enck, ES, P.O. Box 2071,Princeton, N.J. 08540)

13-18. Electronics Div., Electrochemi-cal Soc., Chicago, Ill. (H. R. Huff, TexasInstruments, Inc., Mail Station 202, Dal-las, Tex. 75222)

13-18. Society for Experimental StressAnalysis, Los Angeles, Calif. (B. E. Rossi,SESA, 21 Bridge Sq., Westport, Conn.06880)

14-16. American Assoc. of Petroleum

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Geologi.sts, Anaheim, Calif. (T. L. Bear,Bear & Kistler, 1052 W. 6 St., Los An-geles, Calif. 90017)

14-17. IrregularIties in the EquatorialIonosphere, American Geophysical Union,Dallas, Tex. (A. F. Spilhaus, Jr., AGU,1717 L St., NW, Washington, D.C. 20036)

14-18. Symposium on EnvironmentalBehaviour of Radionuclides Released inthe Nuclear Industry, Intern. AtomicEnergy Agency, Aix-en-Provence, France.(J. H. Kane, Office of Information Ser-vices, U.S. Atomic Energy Commission,Washington, D.C. 20545)

14-18. American Psychiatric Assoc.,M1ontreal, P.Q., Canada. (B. W. Hogan,APA, 1700 18th St., NW, Washington,D.C. 20009)

15-17. American Inst. of Chemists,Houston, Tex. (P. B. Slawter, Jr., AIC.,79 Mladison Ave., New York 10016)

15-17. Electrical and Electronic Mea-stirement and Test Instrument Conf., Ot-tawa, Ont., Canada. (G. R. Symonds,4-261 Fifth Ave., Ottawa KlS 2N4)

15-20. American Physiological Soc.,Atlantic City, N.J. (R. G. Daggs, APS,9650 Rockville Pike, Bethesda, Md. 20014)

16-18. National Soc. for the Preven-tion of Blindness, New York, N.Y. (W.D. David, NSPB, 79 Madison Ave., NewYork 100 16)

16-19. Society of Technical Writers andPublishers, Houston, Tex. (C. T. Young-blood, STWP, Suite 421, 1010 VermontAve., NW, Washington, D.C. 20005)

16-20. American Pediatric Soc., San

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Francisco, Calif. (C. D. Cook, 333 CedatSt., New Haven, Conn. 06510)20-22. Council of Biology Editors,

Bethesda, Md. (K. F. Heumann, Federa-tion of American Socs. for ExperimentalBiology, 9650 Rockville Pike, Bethesda,Md. 20014)

20-23. American Thoracic Soc., NewYork, N.Y. (R. G. Weymueller, ATS,1740 Broadway, New York 10019)

20-23. National Tuberculosis and Res-piratory Disease Assoc., New York, N.Y.(R. J. Anderson, NTRDA, 1740 Broad-way, New York 10019)

20-25. Conference on Mass Spectrom-etry and Allied Topics, 21st, San Fran-cisco, Calif. (F. E. Saalfeld, NavalResearch Lab., Code 6110, Washington,D.C. 20390)20-26. American Gastroenterological

Assoc., New York, N.Y. (J. A. Benson,Jr., 3181 SW Sam Jackson Park Rd.,Portland, Ore. 97201)

20-26. American Soc. for Gastrointes-tinal Endoscopy, New York, N.Y. (J. A.Rinaldo, Jr., ASGE, 16001 W. Nine MileRd., Southfield, Mich. 48075)

21-23. Biomedical Perspectives of Ag-glutinins of Invertebrate and Plant Ori-gins, New York Acad. of Sciences, NewYork, N.Y. (E. Cohen, Roswell Park Me-morial lnst., Buffalo, N.Y.)

21-23. American Soc. for Quality Con-trol, Cleveland, Ohio. (R. W. Shearman,ASQC, 161 W. Wisconsin Ave., Milwau-kee, Wis. 53203)

21-24. American College of Obstetri-cians and Gynecologists, Bal Harbour, Fla.(M. Newton, ACOG, 79 W. Monroe St.,Chicago, Ill. 60603)

21-25. American Industrial HygieneAssoc., Boston, Mass. (G. D. Clayton,AIHA, 25711 Southfield Rd., Southfield,Mich., 48075)

21-26. World Congr. of Otorhinolaryn-gology, 10th, Venice, Italy. (M. Arslan,Clinica ORL, Policlinico, Univ. of Padua,Padua, Italy)

23-25. American Inst. of IndustrialEngineers, Chicago, Ill. (J. F. Jericho,AIlE, 345 E. 47 St., New York 10017)

24-25. Fluorescense: Microscopy, Mea-surements and Photochemistry, intern.symp., Lisbon, Portugal. (A. de LemosBastos, Instituto Portugues de Oncologiade Francisco Gentil, Palhava-Lisboa 4)

27-30. International Congr. of Bron-choesophagology, 14th, Lausanne, Swit-zerland. (J. P. Taillen, Clinique ORL,Hopital Cantonal, 1011 Lausanne)

28-30. American OphthalmologicalSoc., Hot Springs, Va. (R. W. Hollen-horst, AOS, 200 First St., SW, Rochester,Minn. 55901)

29-1. American Orthopsychiatric As-soc., 50th annual, New York, N.Y. (M.F. Langer, AOA, 1790 Broadway, NewYork 1001 9)

30-1. Canadian Meteorological Soc., 7thannual congr., Halifax, N.S. (Miss N.Waller, Maritime Command Headquarters,FMO Halifax, N.S.)

30-1. Laser Engineering and Applica-tions, 4th biennial joint sponsorship ofthe Inst. of Electrical and ElectronicsEngineers and the Optical Soc. of Ameri-ca, Washington, D.C. (D. Edgar, CourtesyAssociates, Suite 700, 1629 K St., NW,Washington, D.C. 20006)

Circle No. 85 on Readers' Service Card

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"The Estuary-Septic Tank of the Megalopolis"

This is but one of 71 scientific papersmaking up the comprehensive volume

ESTUARIESpublished by AAAS in 1967 and re-

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30-1. European Conf. on the Use ofLow Energy Accelerators, Polytechnic ofthe Sotuth Bank and Inst. of Physics,Iondon, England. (A. H. Jiggins, Dept.of Physics. PSB, London, S.E.l OAA)

June

3-5. Royal Soc. of Canada, Kingston,Ont. (Public Relations Dept., RSC, Queen'sUniv., Kingston)

3-7. Special Libraries Assoc., Pitts-bLurgh, Pa. (F. E. McKenna, SLA, 235Park Ave. S., New York 10003)

3-7. Asian Pacific Congr. of PlasticSurgery, Jerusalem, Israel. (N. Ben-Hur.P.O. Box 16271, Tel-Aviv, Israel)

4-6. Brookhaven Symp. in Biology, 25th,Upton, N.Y. (P. S. Carlson, Biology Dept.,Brookhaven Natl. Lab., Upton 11973)

4-8. Carbon, I Ith biennial conf., Amer-ican Carbon Committee, Oak Ridge Natl.Lab., Gatlinburg, Tenn. (W. P. Eatherly,Oak Ridge Natl. Lab., P.O. Box X, OakRidge 37830)

4-8. American Federation of Informa-tion Processing Soc., New York, N.Y. (T.C. White, AFIPS, 210 Summit Ave.,Montvale, N.J. 07645)

4-8. Symposium on Rapid Methodsand Automation in Microbiology, Stock-holm, Sweden. (Miss S. Olsen, Dept. ofApplied Microbiology, Karolinska In-stitutet, S-104 01 Stockholm 60, Sweden)

4-8. American Assoc. for the Study ofNeoplastic Diseases, Heidelberg, Ger-many. (R. H. Jackson, 10607 Miles Ave.,Cleveland, Ohio 44105)

4-9. International Assoc. of Hydro-logical Sciences, Madrid, Spain. (D. R.Dawdy, Engineering Research Center,U.S. Geological Survey, Colorado StateUniv., Fort Collins, Colo. 80521)

6-7. Government Data Systems Conf. onNew Systems in Law Enforcement andCriminal Justice, 2nd natl., New York,N.Y. (WV. A. KuLlok, Div. of Business andManagement, New York Univ., 600 ThirdAve., New York 10016)

6-8. Alaska State Medical Assoc., Fair-banks. (R. G. Ogden, ASMA, 1135 W.8 Ave., Anchorage, Alaska 99501)

6-8. Mode of Action of Mlicrobial Wallsand Mlembranes, New York Acad. of Sci-ences, New York, N.Y. (NI. R. J. Salton,New Yor-k- Univ., New York)

7-9. International Congr. on Immu-nology in Obstetrics and Gynaccology,Padua, Italy. (N. Carretti, Obstetrics andGynaccology Clinic, Univ. of Padua, ViaGiustiniani No. 3, Padua 35100)

7-9. American Rlheumatism Assoc.,Los Angeles, Calif. (Miss L. Bonfiglio,ARA, 1212 Avenue of the Americas,New York 10036)

7-9. MIass Spectrometry in Biochemistryand MTedicine, intern. symp., Milan, Italy.(A. Frigerio, Istituto di Ricerche Farma-cologiche "Mario Negri," 20157 Mlilan-Via Eritrea, 62 Italy)

10-14. Institute of Food Technologists,Miami Beach, Fla. (C. L. Willey, IFT,221 N. LaSalle St., Chicago, 111. 60601)

10-14. Special Libraries Assoc., Phil-adelphia, Pa. (F. E. MIcKenna, SLA, 235Pai-k Ave. S., New York 10003)

10-15. Neturostirgical Soc. of America,Pembroke, Bermuda. (S. N. Chou, Univ.of Nlinnesota Medical School, Minneapolis55455)

16 MARCfH 1973

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Volcanism in Mexico and Central AmericaR. W. Decker

DOI: 10.1126/science.179.4078.1149-a (4078), 1149-1157.179Science 

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trademark of AAAS. is a registeredScienceAdvancement of Science, 1200 New York Avenue NW, Washington, DC 20005. The title

(print ISSN 0036-8075; online ISSN 1095-9203) is published by the American Association for theScience

1973 by the American Association for the Advancement of Science

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