XII. A Century of Zoology in America. Wesley R. Coe 391 XIII. The Development of Botany since 1818. George L. Goodale 439 PORTRAITS Benjamin Silliman _Frontispiece_ From a painting by G. S. Hubbard, Esq., in possession of Miss Henrietta W. Hubbard Benjamin Silliman, Jr. opposite page 28 James D. Dana „ „ 36 Edward S. Dana „ „ 48 Wolcott Gibbs „ „ 52 James Hall „ „ 84 G. K. Gilbert „ „ 140 Edward Hitchcock „ „ 156 O. C. Marsh „ „ 232 F. V. Hayden „ „ 196 J. W. Powell „ „ 204 Clarence King „ „ 208 George J. Brush „ „ 276 J. Willard Gibbs „ „ 324 H. A. Newton „ „ 336 James Clerk Maxwell „ „ 348 Louis Agassiz „ „ 404 Thomas H. Huxley „ „ 410 A. E. Verrill „ „ 412 Asa Gray „ „ 444 Charles Darwin „ „ 452 A CENTURY OF SCIENCE IN AMERICA I THE AMERICAN JOURNAL OF SCIENCE FROM 1818 TO 1918 By EDWARD S. DANA _Introduction._ In July, 1818, one hundred years ago, the first number of the American Journal of Science and Arts was given to the public. This is the only scientific periodical in this country to maintain an uninterrupted existence since that early date, and this honor is shared with hardly more than half a dozen other independent scientific periodicals in the world at large. Similar publications of learned societies for the same period are also very few in number.