PROCEEDINGS OF THE AMERICAN ACADEMY OP ARTS AND SCIENCES, NEW SERIES. Vol. XL WHOLE SERIES. Vol. XIX. FROM MAY, 1883, TO ]\LVY, 1884. SELECTED FROM THE RECORDS. BOSTON: UNIVERSITY PRESS: JOHN WILSON AND SON. 1884- XS d r CONTENTS. PAGE I. Contributions to North American Botany. By Asa Gray . 1 II. Oti the Development of the Posterior Fissure of the Spinal Cord, and the Reduction of the Central Canal, in the Pig. By William Baknes 97 III. The Relation of the External Meatus^ Tympanum, and Eusta- chian Tube to the First Visceral Cleft. By Albert H. TUTTLE Ill IV. The Fossil White Ants of Colorado. By Samuel H. Scudder 133 V. The Zodiacal Light. By Arthur Searle 146 VI. On Certain Substances obtained from Turmeric. By C. Loring Jackson and A. E. Menke 211 VII. On the Action of Phosphorous Trichloride on Aniline. By C. Loring Jackson and A. E. Menke 222 VIII. Researches upon the Photography of Planetary and Stellar Spectra. By the late Henry Draper, M. D., LL. D. . 231 IX. Contributions from the Chemical Laboratory of Harvard Col- lege. On Mucophenoxybromic Acid. By Henry B. Hill and Edward K. Stevens 262 X. Sir William HerscheVs Observations of Variable Stars. By Edward C. Pickering 269 XL Contributions from the Chemical Laboratory of Harvard Col- lege. I. — On ^-Bromtetrachlorpropionic Acid. By Charles F. Mabery 279 II. — On a- and ^-Chlordibromacrylic Acids. By Charles F. Mabery and Rachel Lloyd 281 ni. — On ^-Dibromdichlorpropionic and ^-bromdichloracrylic Acids. By Charles F. Mabery and H. H. Nich- olson . . . , 289 rV. — On Orthoiodtoluolsulphonic Acid. By Charles F. Mabery and George H. Palmer 293 IV C0NTENT6. PAGE XII. Recent Observations of Variable Stars. By Edward C. Pickering 296 XIII. The Phases of the Moon. By Arthur Searle .... 310 XIV. Mean Right Ascensions of 133 Stars near the North Pole, observed in 1S82 and 1883, at the Field Memorial Observa- tory of Wiiliams Colkfje. By Truman Henry Safkoud 321 XV. A New Theory of Cohesion applied to the Thermodynamics of Liquids and Solids. By Harold Whiting, A. M. . . 353 Proceedings 467 Memoirs : — Ezra Abbot 487 Calvin Ellis 492 Evangelinus Apostolides Sophocles 502 Stephen Alexander 504 John Lawrence Le Conte 511 George Engelmann 516 Arnold Guyot 522 Andrew Atkinson Humphreys 526 William Augustus Norton 530 J. Lawrence Smith 535 Joachim Barrande 539 Jean-Baptiste-Andre Dumas 545 Oswald Heer 556 Fran9ois-Auguste-Alexis Mignet 559 Sir Edward Sabine .560 Johann Friedrich Julius Schmidt 564 Gabriel Gustav Valentin 567 Charles Adolphe Wurtz 568 List of the Fellows and Foreign Honorary Members . . 571 Index 579 PROCEEDINGS OF THE AMERICAN ACADEMY OF ARTS AND SCIENCES. VOL. XIX. MARINE BIOLOGICAL LABORATORY. Received /;^^^X;,./. B. Clevelandi. Branches and peduncles slightly pubescent ; bracts of invo- lucre 8 to 12, ovate, rather obtuse, with one or three obscure nerves at base ; rays oval ; young akenes minutely scabro-hispidulous ; paleac of pappus slcnder- awned, only 2 in disk and ray. — Near San Diego, Cleveland, 1874. *+ ++ Nearly filiform leaves 3-5-parted or some entire. B. PLATYCARPHA, Gray, 1. c. Sligiitly pubescent throughout; bracts of invo- lucre 6 or 7, ovate, acutish, lightly and about equally 3-nerved at base ; rays narrowly oblong ; paleae of pappus slendcr-awned, 6 or 7 both in ray and disk. — Thus far received only from the valley of the Sacramento, station unknown, coll. by Slillman. § 2. DiCH^TA. {Dichceta, Nutt.) Pappus (occasionally wanting) of two forms, * Unlike in disk and raj', in both of about 5 fimbriate-laciniate paleaj, in the former awned, in tlie latter mostly muticous : leaves entire. B. Palmeri, Gray, Bot. Calif, i. 37G, is only of Guadalupe Island off Lower California, Palmer. * * Not unlike in disk and ray, composed in both of truncate or muticous short paleoe between 2 or 3 awned ones or naked awns. H- Rays hardly exsertcd : leaves all entire : pappus of 3 to 5 awns and at least twice as many squamellate narrow laciniate palea;. B. MARiTiMA, Gray. Farralones Islands. Should be collected anew. +- •<- Rays usually exserted : pappus sometimes wanting : some of the leaves laciniate or pinnatifid: involucral bracts of the next section. — Dicliata, 'iHutt. B. FuEMONTi, Gray. Leaves slender; pappus of 4 slender awns and of nar- row entire or 2-cleft small paleJE. B. uLiGiNOSA, Gray. Leaves linear or broader, the lower once or twice pinna- tifi