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PROCEEDINGS

OF THE

AMERICAN ACADEMY

r

OF

ARTS AND SCIENCES.

NEW S E R I E S. Vol. IV.

WHOLE SERIES. Vol. XIL

from may, 1876, to may, 1877. SELECTED FROM THE RECORDS.

BOSTON: PRESS OF JOHN WILSON AND SON.

1877.

^ • 1 -Slo

2 ^' ^ I

CONTENTS.

PAGE

I. Researches in Telephony. By A. Graham Bell ... 1 II. ScheeWs Green : Its Composition as usunlbj prepared, and Some Experiments upon Arsenite of Copper. By S. P. Sharples, S. B 11

III. Contributions from the Chemical Laboratory of Harvard

College : —

1. On the Ethers of Uric Acid. By H. B. Hill . . 26

2. On Some of the Salts of Methyluric Acid, Q H^ (CH^)

N^O^. By Oscar R. Jackson 36

IV. Contributions from the Physical Laboratory of the Massa-

chusetts Institute of Technology : —

11. On the Effect of Temperature on the Viscosity of Air.

By Silas W. Holman 41

V. Contributions to the Botany of North America. By Asa

Gray 51

VI. Contributions from the Laboratory of S. P. Sharpies : —

Schweinfurt Green : Some Experiments on the Action of Arsenic Trioxide on Copper Acetate, with the View of Investigating the Composition of the above Com- pound. By E. R. Hills 85

VII. Milk Analyses. By S. P. Sharples 98

VIII. On a New Mode of Manipulating Hydric Sulphide. By

JOSIAH P. CoOKE, Jr 113

IX. On the Process of Reverse Filtering and its Application to Large

Masses of Material. By Josiah P. Cooke, Jr. . . . 124 X. Contributions from the Physical Laboratory of Harvard College : —

12. On Vortex Rings in Liquids. By Johx Trow-

bridge 131

XL Contributions from the Physical Laboratory of Harvard College : —

14. On a New Method of Comparing the Electro-motive

Forces of Two Batteries and Measuring their Inter- nal Resistance. By B. O. Peirce, Jr. . . . 137

15. On a New Method of Measuring the Resistance of a

Galvanic Battery. By B. O. Peirce, Jr. . . 140

IV CONTENTS.

PAGE

XII. Note on (lie Deternnnation of the Law of Propagation of Heat

in the Interior of a Solid Body. By B. O. Peirce, Jr. 143 XIII. Antigeny, or Sexual Dimorphism in Butterflies. By

Samuel H. Scudder 150

XIY. Characters of some Little-knoxvn or New Genera of Plants.

By Asa Gray 159

XV. Ohserrationes Liche7iologicce, No. 4. Observations on North American and other Lichens. By Edward Tucker-

max, M.A 166

XVI. Theory of the Horizontal Photohelio graph, including its Ap- plication to the Determination of the Solar Parallax by Means of Tra?isits of Venus. By Professor William

Harkness, U. S. X 186

XVII. On Diamido-sulpliobenzide-dicarhoriic Acid. By Arthur

Michael and T. H. Xorton 205

XVIII. Contributions from the Chemical Laboratory of Harvard College : —

Pccsearches on the Substituted Benzyl Compounds. By

C. LoRixG Jackson 209

First Paper. On Certain Substituted Benzylbrom-

ides. C. LoRiNG Jackson 211

Second Paper. On Parabrombenzyl Compounds.

Woodbury Lowery 221

XIX. Contribution toward the History of the Fluorides of Man- ganese. By W. H. Melville 228

XX. On some Algce new to the United States. By W. G. Far- low 235

Description of a New Alga of California. By Professor

Daniel C. Eaton, of Yale College 245

XXI. Descriptions of New Species of Plants, with Revisions of Cer- tain Genera. By Sereno Watson 246

Proceedings 279

List of the Fellows and Foreign Honorary Members 336 Index 343

PROCEEDINGS

OF THE

AMERICAN ACADEMY

OF

ARTS AND SCIENCES.

VOL. XII. PAPERS READ BEFORE THE ACADEMY.

I.

RESEARCHES IN TELEPHONY. By A. Graham Bell.

Presented May 10, 1876, by the Corresponding Secretary.

1. It has long been known that an electro-magnet gives forth a decided sound when it is suddenly magnetized or demagnetized. "When the circuit upon which it is placed is rapidly made and broken, a succession of explosive noises proceeds from the magnet. These' sounds produce upon the ear the effect of a musical note, when the current is interrupted a sufficient number of times per second. The discovery of " Galvanic Music," by Page,* in 1837, led inquirers in dif- ferent parts of the world almost simultaneously to enter into the field of telephonic research ; and the acoustical effects produced by magnetization were carefully studied l)y Marrian,t Beatson,! Gassiot,§ De la Rive,||

* C. G. Page. "The Production of Galvanic Music." Sllliman's Journ.,

1837, XXXII., p. .596; Silliman's Journ., July, 1837, p. 854; Silliman's Journ.,

1838, XXXIIL, p. 118; Bibl. Univ. (new series), 1839, XL, p. 398.

t J. P. Marrlan. Phil. Mag., XXV., p. 382; Inst., 1845, p. 20; Arch, de l']fclectr.,V., p. 105.

t IF. Bfalson. Arch, de I'Electr., V., p. 197 ; Arch, de Sc. Phys. et Nat. (2d series), II., p. 113.

§ Gassiot. See " Treatise on Electricity," by De la Rive, I., p. 300.

II De la Rive. Treatise on Electricity, I., p. 300; Phil. Mag., XXXV., p. 422 ; Arch, de I'Electr., V., p 200; Inst., 184G, p. 83; Coniptes Kendus, XX., p. 1287; Comp. Rend., XXII., p. 432; Pogg. Ann., LXXVI., p. 637; Ann. de Chim. et de Phys., XXVI., p. 158.

VOL. Xll. (n. S. IV.) 1

2 PROCEEDINGS OF THE AMERICAN ACADEMY

Matteucci,* Guillemin,t Wertheim,| "\Vartraann,§ Janniar,]| Joiile,11 Laborde,** Legat,tt Reis,tl PoggeiidorfF,§§ Du Moucel,|||| Dele- zenne,1[ir and others.***

2. In the autumn of 1874, I discovered that the sounds emitted by an electro-magnet under the influence of a discontinuous current of electricity are not due wholly to sudden changes in the magnetic con- dition of the iron core (as heretofore supposed), but that a portion of the effect results from vibrations in the insulated copper-wires composing the coils. An electro-magnet was arranged upon circuit with an in- strument for interrupting the current, — the rheotome being placed in a distant room, so as to avoid interference with the experiment. Upon applying the ear to the magnet, a musical note was clearly per- ceived, and the sound persisted after the iron core had been removed. It was then much, feebler in intensity, but was otherwise unchanged, — the curious crackling noise accompanying the sound being well marked.

The effect may probably be explained by the attraction of the coils of the wire for one another during the passage of the galvanic current,

* Matteucci. Inst., 1845, p. 315 ; Arch, cle I'Electr., V., 389. t Gui/leniin. Corap. Rend., XXII., p. 264; Inst., 1846, p. 30; Arch. d. So. Phys. (2d series), I., p. 191.

I G. Wertheim. Comp. Rend., XXII., pp. 336, 544; Inst., 1846, pp. 65, 100; Pogg. Ann., LXVIII.,p. 140; Comp. Rend., XXVI., p. 505; Inst., 1848, p. 142; Ann. de Chim. et de Phys., XXIII., p. 302; Arch. d. Sc. Phys. et Nat., VIII., p. 206 ; Pogg. Ann., LXXVII., p. 43 ; Borl. Ber., IV., p. 121.

§ Elie ]Vartmann. Comp. Rend., XXII., p. 544; Phil. Mag. (3d series), XXVIII., p. 544; Arch. d. Sc. Phys. et Nat. (2d series), I., p. 419; lust., 1846, p. 290; Monatscher. d. Berl. Akad., 1846, p. 111.

II Janmar. Comp. Rend., XXIII., p. 319; Inst., 1846, p. 269; Arch. d. Sc. Phys. et Nat. (2d series), II., p. 394.

IF J. P. Joule. Piiil. Mag., XXV., pp. 76, 225 ; Berl. Ber., III., p. 489.

** Lahorde. Comp. Rend., L., p. 692; Cosmos, XVII., p. 514.

tt Legal. Brix. Z. S., IX., p. 125.

\X Reis. " Te'le'phonie." Polytechnic Journ., CLXVIII., p. 185; Bottger's Notizbl., 1863, No. 6.

§§ J. C. Poggendorff. Pogg. Ann., XCVIII., p. 192; Berliner Monatsber., 1856, p. 133 ; Cosmos, IX., p. 49 ; Berl. Ber., XII., p. 241 ; Pogg. Ann., LXXXVII., p. 139.

nil Du Moncel. Expose, II., p. 125; also. III., p. 83.

Tn[ Delezenne. " Sound produced by Magnetization," Bibl. Univ. (new series), 1841, XVI., p. 406.

*** See London Journ., XXXII., p. 402; Polytechnic Journ., CX., p. 16;

Cosmos, IV., p. 43 ; Glosener Traite' gene'ral, &c., p. 350 ; Dove.-Repert.,VI.,

p. 58 ; Pogg. Ann., XLIII., p. 411 ; Berl. Ber., I., p. 144; Arch. d. Sc. Phys. et Nat., XVI., p. 406 ; Kuhn's Encyclopedia der Physik, pp. 1014-1021.

OF ARTS AND SCIENCES. 6

and the sudtlen cessation of such attraction when the current is inter- rupted. When a spiral of fine wire is made to dip into a cup of mer- cury, so as thereby to close a galvanic circuit, it is well known that the spiral coils up and shortens. Ferguson * constructed a rheotome upon this principle. The shortening of the spiral lifted the end of the wire out of the mercury, thus opening the circuit, and the weight of the wire sufficed to bring the end down again, — so that the spiral was thrown into continuous vibration. I conceive that a somewhat similar motion is occasioned in a helix of wire by the passage of a discontinu- ous current, although further research has convinced me that other causes also conspire to produce the effect noted above. The extra currents occasioned by the induction of the voltaic current upon itself in the coils of the helix no doubt play an important part in the pro- duction of the sound, as very curious audible effects are produced by electrical impulses of high tension. It is probable, too, that a molecular vibration is occasioned in the conducting wire, as sounds are emitted by many substances when a discontinuous current is passed through them. Very distinct sounds proceed from straight pieces of iron, steel, retort-carbon, and plumbago. I believe that I have also obtained audible effects from thin platinum and German-silver wires, and from mercury contained in a narrow groove about four feet long. In these cases, however, the sounds were so faint and outside noises so loud that the experiments require verification. "Well-marked sounds proceed from conductors of all kinds when formed into spirals or helices. I find that De la Rive had noticed the production of sound from iron and steel during the passage of an intermittent current, although he failed to obtain audible results from other substances. In order that such effects should be observed, extreme quietness is necessary. The rheotome itself is a great source of annoyance, as it always produces a sound of similar pitch to the one which it is desired to hear. It is absolutely requisite that it should be placed out of earshot of the observer, and at such a distance as to exclude the possibility of sounds being mechanically conducted along the wire.

3. Very striking audible effects can be produced upon a short circuit by means of two Grove elements. I had a helix of insulated copper-wire (No. 23) constructed, having a resistance of about twelve ohms. It was placed in circuit with a rheotome which interrupted the current one hundred times per second. Upon placing the helix to my ear I

* Ferguson. Proceedings of Royal Scottish See. of Arts, April 9, 18G6; Paper on "A New Current Interrupter."

4 PROCEEDINGS OF THE AMERICAN ACADEMY

could hear the unison of the note produced by the rheotome. The intensity of the sound was much increased by placing a wrouglit-iron nail inside the helix. In both these cases, a crackling effect accompa- nied the sound. When the nail was held in the fingers so that no portion of it touched the helix, the crackling effect disappeared, and a pure musical note resulted.

When the nail was placed inside the helix, between two cylindrical pieces of iron, a loud sound resulted that could be heard all over a large room. The nail seemed to vibrate bodily, striking the cylindrical pieces of metal alternately, and the iron cylinders themselves were violently agitated.

4. Loud sounds are emitted by pieces of iron and steel when sub- jected to the attraction of an electro-magnet which is placed in cir- cuit with a rheotome. Under such circumstances, the armatures of Morse-sounders and Eelays produce sonorous effects. I have succeeded in rendering the sounds audible to large audiences by interposing a tense membrane between the electro-magnet and its armature. The armature in this case consisted of a piece of clock- spring glued to the membrane. This form of apparatus I have found invaluable in all my experiments. The instrument was connected with a parlor organ, the reeds of which weie so arranged as to open and close the circuit during their vibration. When the organ was played the music was loudly reproduced by the telephonic i-eceiver in a distant room. When chords were played upon the organ, the various notes composing the chords were emitted simultaneously by the armature of the receiver.

5. rhe simultaneous production of musical notes of different pitch by tlie electric current, was foreseen by me as early as 1870, and demonstrated during the year 1873. Elisha Gray,* of Chicago, and Paul La .Cour,t of Copenhagen, lay claim to the same discovery. The fact that sounds of different pitch can be simultaneously produced upon any part of a telegraphic circuit is of great practical importance ; for the duration of a musical note can be made to signify the dot or dash of the Morse alphabet, and thus a number of telegraphic mes- sages may be sent simultaneously over the same wire without confusion by making signals of a definite pitch for each message.

6. If the armature of an electro-magnet has a definite rate of oscil- lation of its own, it is thrown bodily into vibration when the interrup-

* ElUha Gray. Eng. Pat. Spec, No. 974. See " Engineer," March 26, 1876. t Paul la Cour. Telegraphic Journal, Nov. 1, 1875.

OF ARTS AND SCIENCES. 5

lions of the current are timed to its movements. For instance, present an electro-magnet to the strings of a piano. It will be found that the etrinjj which is in unison with the rheotome included in the circuit will be thrown into vibration by the attraction of the magnet.

liehnholtz,* in his experiments upon the synthesis of vowel sounds caused continuous vibration in tuning-forks which were used as the armatures of electro-magnets. One of the forks was employed as a rheotome. Platinum wires attached to the prongs dipped into mer- cury.

The intermittent current occasioned by the vibration of the fork traversed a circuit containing a number of electro-magnets between the poles of which were placed tuning-forks whose normal rates of vibration were multiples of that of the transmitting fork. All the forks were kejjt in continuous vibration by the passage of the inter- rupted current. By re-enforcing the tones of the forks in different degrees by means of resonators, Helmholtz succeeded in reproducing artificially certain vowel sounds.

I have caused intense vibration in a steel strip, one extremity of which was firmly clamped to the pole of a U-shaped electro-magnet, the free end overhanging the otlier pole. The amplitude of the vibration was greatest when the coil was removed from the leg of the magnet to which the armature was attached.

7. All the effects noted above result from rapid interruptions of a voltaic current, but sounds may be produced electrically in many other ways.

The Canon Gottoin de Coma,t in 1785, observed that noises were emitted by iron rods placed in the open air during certain electrical conditions of the atmosphere ; Beatson $ produced a sound from an iron wire by the discharge of a Leyden jar; Gore § obtained loud musical notes from mercury, accompanied by singularly beautiful cris- pations of the surface during the course of experiments in electrolysis ; and PagH || produced musical tones from Trevelyan's bars by the action of the galvanic current.

8. When an intermittent current is passed through the thick wires of a Ruhmkorff's coil, very curious audible effects are produced by the

* Helmholtz. Die Lelire von dem Tonempfindungen.

t See " Treatise on Electricity," by De la Rive, I., p. 300.

X Ihid.

§ Gore. Proceedings of "Royal Society, XII., p. 217.

II Page. " Vibration of Trevelyan's bars by the galvanic current." SiUi- man's Journal, 1850, IX., pp. 105-108.

6 PROCEEDINGS OF THE AMERICAN ACADEMY

currents induced in the secondary wires. A rheotome was placed in circuit with the thick wires of a Ruhmkorff's coil, and the fine wires were connected with two strips of brass (A and B), insulated from one another by means of a sheet of paper. Upon placing the ear against one of the strips of brass, a sound was perceived like that described above as proceeding from an empty helix of wire during the passage of an intermittent voltaic current. A similar sound, only much more intense, was emitted by a tin-foil condenser when connected with the fine wires of the coil.

One of the strips of brass, A (mentioned above), was held closely against the ear. A loud sound came from A whenever the slijs B was touched with the other hand. It is doubtful in all these cases whether the sounds proceeded from the metals or from the imperfect conductors interposed between them. Further experiments seem to favor the latter supposition. The strips of brass A and B were held one in each hand. The induced currents occasioned a muscular tremor in the fingei'S. Upon placing my forefinger to my ear a loud crackling noise was audible, seemingly proceeding from the finger itself. A friend who was present placed my finger to his e.ar, but heard nothing. I requested him to hold the strips A and B himself. He was then dis- tinctly conscious of a noise (which I was unable to jierceive) proceed- ing from his finger. In these cases a portion of the induced currents passed through the head of the observer when he placed his ear against his own finger ; and it is possible that the sound was occasioned by a vibration of the surfaces of the ear and finger in contact.

When two persons receive a shock from a Ruhmkorff's coil by clasping hands, each taking hold of one wire of the coil with the free hand, a sound proceeds from the clasped hands. The effect is not produced when the hands are moist. When either of the two touches the body of the other a loud sound comes from the parts in contact. When the arm of one is placed against the arm of the other, the noise produced can be heard at a distance of several feet. In all these cases a slight shock is experienced so long as the contact is preserved. The introduction of a piece of paper between the parts in contact does not materially interfere with the production of the sounds, while the unpleasant effects of the shock are avoided.

When a powerful current is passed through the body, a musical note can be perceived when the ear is closely applied to the arm of the person experimented upon. The sound seems to proceed from the muscles of the fore-arm and from the biceps muscle. The musical note is the unison of the rheotome employed to interrupt the primary

OP ARTS AND SCIENCES. 7

circuit. I failed to obtain audible effects in tbis way when the pitch of the rbeotome was high. Elisha Gray * has also produced audible effects by the passage of induced electricity through the human body. A musical note is occasioned by the spark of a Ruhmkorff's coil when the primary circuit is made and broken sufficiently rapidly. When two rheotomes of different pitch are caused simultaneously to open and close the primary circuit, a double tone proceeds from the spark.

9. AVhen a voltaic battery is common to two closed circuits, the current is divided between them. If one of the circuits is rapidly opened and closed, a pulsatory action of the current is occasioned upon the other.

All the audible effects resulting from the passage of an intermittent current can also be produced, though in less degree, by means of a pulsatory current.

10. When a permanent magnet is caused to vibrate in front of the pole of an electro-magnet, an undulatory or oscillatory current of electricity is induced in the coils of the electro-magnet, and sounds proceed from the armatures of other electro-magnets placed upon the circuit. The telephonic receiver referred to above (par. 4), was con- nected in circuit with a single-pole electro-magnet, no battery being used. A steel tuning-fork which had been previously magnetized was caused to vibrate in front of the pole of the electro-magnet. A musical note similar in pitch to that produced by the tuning-fork proceeded from the telephonic receiver in a distant room.

11. The effect was much increased when a battery was included in the circuit. In this case, the vibration of the permanent magnet threw the battery-current into waves. A similar effect was produced by the vibration of an unmagnetized tuning-fork in front of the electro-magnet. The vibration of a soft iron armature, or of a small piece of steel spring no larger than the pole of the electro-raagnet in front of which it was placed, sufficed to produce audible effects in the distant room.

12. Two sino-le-pole electro-magnets, each having a resistance of ten ohms, were arranged upon a circuit with a battery of five carbon elements. The total resistance of the circuit, exclusive of the battery, was about twenty-five ohms. A drum-head of gold-beater's skin, seven centimetres in diameter, was placed in front of each electro- magnet, and a circular piece of clock-spring, one centimetre in diameter, was glued to the middle of each membrane. The telephones so constructed were placed in different rooms. One was retained in

* Elisha Gray. Eng. Pat. Spec, No. 2646, see " Engineer," Aug. U, 1874.

8 PROCEEDINGS OP THE AMERICAN ACADEMY

the experimental room, and the other taken to the basement of an adjoining house.

Upon singing into the telephone, tlie tones of the voice were re- produced by the instrument in the distant room. When two persons sang simultaneously into the instrument, two notes were emitted simul- taneously by the telephone in the other house. A friend was sent into the adjoining building to note the effect produced by articulate speech. I placed the membrane of the telephone near my mouth, and uttered the sentence, "Do you understand what I say ? " Presently an answer was returned through the instrument in my hand. Articu- late words proceeded from the clock-spring attached to the membrane, and I heard the sentence : " Yes ; I understand you perfectly."

The articulation was somewhat muffled and indistinct, although in this case it was intelligible. Familiar quotations, such as, "To be, or not to be ; that is the question." " A horse, a horse,*my kingdom for a horse." " What hath God wrought," &c., were generally understood after a few repetitions. The effects were not sufficiently distinct to admit of sustained conversation through the wire. Indeed, as a gen- eral rule, the articulation was unintelligible, excepting when familiar sentences were employed. Occasionally, however, a sentence would come out with such startling distinctness as to render it difficult to believe that the speaker was not close at hand. No sound was audible when the clock-spring was removed from the membrane.

The elementary sounds of the English language were uttered suc- cessively into one of the telephones and the effects noted at the other. Consonantal sounds, with the exception of L and M, were unrecog- nizable. Vowel-sounds in most cases were distinct. Diphthongal vowels, such as a (in ale), o (in old), i (in isle), oiv (in now), oy (in boy), oor (in poor), oor (in door), ere (in here), ere (in there), were well marked.

Triphthoogal vowels, such as ire (in fire), our (in flour), ower (in mower), ayer (in player), were also distinct. Of the elementary vowel-sounds, the most distinct were those which had the largest oral apertures. Such were a (in far), aw (in law), a (in man), and e (in men).

13. Electrical undulations can be produced directly in the voltaic current by vibrating the conducting wire in a liquid of high resistance included in the circuit.

The stem of a tuning-fork was connected with a wire leading to one of the telephones described in the preceding paragraph. While the tuning-fork was in vibration, the end of one of the prongs was dipped

OF ARTS AND SCIENCES. 9

into water included in tlie circuit. A sound proceeded from the distant telephone. When two tuning-forks of different pitch were connected together, and simultaneously caused to vibrate in the water, two musical notes (the unisons respectively of those produced by the forks) were emitted simultaneously by the telephone.

A platinum wire attached to a stretched membrane, completed a voltaic circuit l)y dipping into water. Upon speaking to the membrane, articulate sounds proceeded from the telephone in the distant room. The sounds produced by the telephone became louder when dilute sul- phuric acid, or a saturated solution of salt, was substituted for the water. Au'lible effects were also produced by the vibration of plumbago in mercury, in a solution of bichromate of potash, in salt and water, in dilute sulphuric acid, and in pure water.

14. Sullivan * discovered that a current of electricity is generated by the vibration of a wire composed partly of one metal and partly of another ; and it is probable that electrical undulations were caused by the vibration. The current was produced so long as the wire emitted a musical note, but stopped immediately upon the cessation of the sound.

15. Although sounds proceed from the armatures of electro-magnets under the influence of uiidulatory currents of electricity, I have been un- able to detect any audible effects due to the electro- magnets themselves. An undulatory current was passed through the coils of an electro- magnet which was held closely against the ear. No sound was per- ceived until a piece of iron or steel was presented to the pole of the magnet. No sounds either were observed when the undulatory cur- rent was passed through iron, steel, retort-carl)on, or plumbago. In these respects an undulatory current is curiously different from an inter- mittent one. (See par. 2.)

16. The telephonic effects described above are produced by three distinct varieties of currents, which I term respectively intermittent, pulsatory, and undulatory. Intermittent currents are characterized by the alternate presence and absence of electricity upon the circuit ; Pulsatory currents result from sudden or instantaneous changes in the intensity of a continuous current ; and undulatory currents are pro- duced by gradual changes in the intensity of a current analogous to the changes in the density of air occasioned by simi)le jiendulous vibrations. The varying intensity of an undulatory current can be

* Sullivan. " Currents of Electricity produced by the vibration of Metals." Phil. Mag., 1845, p. 201; Arch, de I'^lectr., X., p. 480.

10

PROCEEDINGS OF THE AMERICAN ACADEMY

represented by a sinusoidal curve, or by the resultant of several sinus- oidal curves.

Intermittent, pulsatory, and undulatory currents may be of two kinds, — voltaic, or induced; and these varieties may be still further discriminated into direct and reversed currents ; or those in which the electrical impulses are all positive or negative, and those in which they are alternately positive and negative.

I 00

(

^ s

CD in

H ^

Intermittent.

( Voltaic. (^ Induced.

{

( Reversed (See par. 8).

Direct (See par. 1, 2, 3, 4, 5, 6).

Reversed.

Direct.

a

_ r^ •— '

.--^Pulsatory-

\

Voltaic,

Undulatory.

\

( Direct (See par. 9). ( Reversed.

/ Induced. < r, ' j ^ I Reversed.

ect (See par. 11, 12, 13, 15).

versed. Direct. Reversed (See par. 10).

Voltaic.

Induced.

( Direc ( Reve

{

17. In conclusion, I would say that the different kinds of currents described above may be studied optically by means of Konig's mano- metric capsule.* The instrument, as I have employed it, consists simjily of a gas-chamber closed by a membrane to which is attached a piece of clock-spring. When the spring is subjected to the attraction of an electro-magnet, through the coils of which a "telephonic " current of electricity is passed, the flame is thrown into vibration.

I find the instrument invaluable as a rheometer, for an ordinary galvanometer is of little or no use when " telephonic " currents are to be tested. For instance, the galvanometer needle is insensitive to the most powerful undulatory current when the impulses are reversed, and is only slightly deflected when they are direct. The manometric cap- sule, on the other hand, affords a means of testing the amplitude of the electrical undulations; that is, of deciding the difference between the maximum and minimum intensity of the current.

* Konig. " Upon Manometric Flames," Phil. Mag., 1873, XLV., No. 297, 298.

OP ARTS AND SCIENCES. 11

II.

SCHEELE'S GREEN,

ITS COMPOSITION AS USUALLY PREPARED, AND SOxME EX- PERIMENTS UPON ARSENITE OF COPPER.

By S. p. Sharples, SB.

Presented, June 14, 1876.

In 1778, the eminent Swedish chemist, Charles William Scheele, com- municated to the Academy of Sciences at Stockholm the method of preparing the green pigment which has since borne his name. He, however, says, that it was discovered three years previously.

This piument is of a yellowish green color, and has been long used in the arts under various names ; such as, mountain green, mineral green, and Swedish green. At the time of its discovery, it was the most brilliant green obtainable.

The discovery, in. 1814, of the copper aceto-arsenite, known as Schweinfurth green, Paris green, English green, and sometimes wrongly called Scheele's green, has, however, almost entirely tlirown Scheele's green out of the market ; and it is at the present day an unknown sub- stance, so far as its use as a pigment is concerned ; although it may be still found on the price lists of manufacturing chemists, and the receipts for its manufacture are found in works on dyeing and calico-printing. But its covering power is very low, and it is far inferior in brilliancy to its successful rival, Paris green.

Having had occasion to examine some samples of this pigment some time ago, I became convinced that the composition of Scheele's green, as laid down in the books, was altogether a matter of conjecture ; since I could find no record of any analysis that had ever been made of the substance prepared according to Scheele's directions, which have been copied without change for the last hundred years.

The formula given varies with the date ; Scheele himself, of course, neither made a quantitative analj'sis nor gave a formula. Succeeding writers seem to have followed him in the first respect, but have given formulas to correspond with their ideas of the composition that the salt should have.

12 PROCEEDINGS OP THE AMERICAN ACADEMY

The older writers give the formula CuOAs^Og, this would give the percentages of copper oxide and arsenic trioxide, as follows : —

Copper oxide, 29.50

Arsenic trioxide, 70.50

100.00

(The atomic weights used through this paper are: oxygen, 16; copper, 63.4 ; the old formulas being changed to correspond to these weights. As a matter of convenience, I have made all statements of composition in terms of copper oxide and arsenic trioxide, but in so doing I have no wish to be understood as asserting that they exist as copper oxide and arsenic trioxide in the compound.)

Berzelius * gives the formula, Cu2:S.s ; this, in modern notation, would be Cu^As^Og ; or in percentages.

Copper oxide, 44.50

Arsenic trioxide, 55.50

100.00

He describes the methods by which it may be obtained as either, by digesting carbonate of copper with water and arsenious acid, or by Scheele's method, giving for the latter almost exactly Sclieele's receipt. Ure t gives Scheele's receipt, and then says it consists of oxide of copper, 28.51, arsenious acid, 71.46. This corresponds to the first formula given above, CuAs^O^.

Miller t gives the formula CuHAsOg. This in percentages would be:

Copper oxide, 42.37

Arsenic trioxide, 52.83

Water, 4.80

This formula seems to be the favorite one at present, and may be found in most of the text-books.

Bloxam,§ in the course of his long and elaborate investigations of the arsenites, made some experiments upon copper arsenite, but failed to obtain a definite compound. The first salt made, he says, contained : —

« Ure's Diet., New York, 1847, p. 1100.

t Traite ile Cliemie, Tome 4, p. 182. Paris, 1847.

t Miller's Elements of Chemistry. London, 1864, p. 292.

§ Bloxam, C. L., Jour. Chem. Soc, 1862, p. 292.

OF ARTS AND SCIENCES.

13

Per cente.	Equivalents.
40.54	1.88
53.80	1.
5.67	1.16
Per cents.	Equivalents.
44.29	2.21
49.98	1.00
5.73	1.26
Per cents.	Equivalents.
46.52	2.35
49.36	1.00
4.12	.92
Per cents.	Equivalents.
42.69	1.96
52.67	1.
4.64	.97

Copper oxide, Arsenic trioxide, "Water,

The second contained : —

Copper oxide, Arsenic trioxide. Water,

The third product gave : —

Copper oxide. Arsenic trioxide, Water,

The fourth gave : —

Copper oxide. Arsenic trioxide, Water,

From this last analysis he deduces the formula CuIIAsO.. In a foot-note he says : " Scheele's prescription for the commercial green arsenite of copper involves 2.3 equivalents of oxide of copper for one equivalent of arsenious acid, so that Scheele's green dried at 212° F., appears to be essentially a mixture of CuHAsO^, with an excess of oxide of cojiper."

This observation is perfectly correct if nothing is taken into the ac- count except the quantities taken by Scheele ; but Sclieele himself says, in a foot-note:* "Tlie water with which the color is lixiviated con- tains a little arsenic, and must not be thrown out in a place to which cattle have access." The evident tendency of this loss of arsenic would be to make the salt more basic than the formula (CuO)2.32As„03 (H.,0)g2 calls for, this being the formula which Bloxam supposes to represent Scheele's green.

In Watts's Dictionary,! under the head of arsenite of copper, this sentence occurs : " It is a light green precipitate, which dissolves in an excess of ammonia, without color, yielding a solution of arsenic acid and cuprous oxide."

Berzelius's formula is given, and the sentence just quoted is evi-

* Scheele's Essays. London, 1786, p. 254. t Vol. I., p. 376.

14 PROCEEDINGS OF THE AMERICAN ACADEMY

dently a translation, either directly or indirectly, from the same author.

The description of copper arsenite in the French edition of Ber- zelius, Paris, 1847, is as follows: "The neutral salt is obtained by precijiitatinLT sulphate of copper by arsenite of potassa. The precipi- tate is green. When it contains an excess of base, its color is more in- tense ; but it decomposes spontaneously, in a little time becoming a dark brown, and then contains cupric arsenate and cuprous arsenite. Caustic ammonia dissolves this salt into a colorless liquid containing, probably, cuprous arsenate." The German of 1838 is the same as the above, with the exception that it reads : " When the alkali is in excess, the color is more intense, but it decomposes in a little time," &c. " This salt " referred to in the above paragraph, is evidently the brown salt, and not the green. Moreover, the German text, and not the French, is the coi'rect one, as is shown by my own experiments.

In this connection, the following extract is of interest. Rose says of Scheele's green : " This precipitate is soluble in an excess of ammonia, also in an excess of hydrate of potassa. The solution has in both cases a similar blue color. The blue solution formed by hydrate of potassa deposits in time reddish-brown suboxide of copper ; the liquid becomes colorless, and contains arsenate of potMssium. The blue solution formed by ammonia is not modified by time."

The reference from Berzelius seems to have been misunderstood by German as well as English writers, as the same statement occurs in the Handworterbuch der Chemie, B. 2, 1858, p. 300, which says Scheele's green dissolves colorless in ammonia as arsenic acid and cuprous oxide. Graham-Otto * also repeats the same.

In the New Chemistry,! the above blunder is repeated, and two formulas are given, as follows : " Arsenite of copper, (Cu.,0)2As.,03 or, Cu./AsO,)^." And the article finishes by saying there are also two hydrated salts, CuH_,(As0.5)2, and CuHAsOn. The percentage com- position of these salts would be as follows, supposing the above formulas are correctly given : —

Copper Arsenic	CCusC oxide, (sub. trioxide,	O2AS2O3. 59.06) 40.94	CU3(AS03)2. 54.61 45.39	CuH4(As03)o. 25.33 63.18	CUHASO3. 42.37 52.83
Water,					11.49	4.80

* Vol. III., 557, 4th ed.

t Chemistry, Theoretical and Practical. Lippincott & Co. ; Phila., 1876, p. 260.

OF ARTS AND SCIENCES. 15

In the first of these formulas, there is an evident mistake ; it is a copy of the formula given by Watts, without takiug into account that Watts, while doubling the atomic weight of oxygen, retained the old weight of copper, so that, corrected, this formula reads (CuO)2 ASjOj ; or, in other words, is Berzelius's formula.

But both of the formulas, one and two, are wrong, from the fact that they contain no water. No. 3 is an evident attempt to represent the acid arsenite which Berzelius mentions, and No. 4 is Bloxam's formula.

As will be seen, the whole literature of the subject is founded upon three sets of facts. Scheele's prescription, which all the authors, whom I have quoted, have given, making only such alterations as were necessary on account of chancres in weights and measures. And it is a sintjular fact, that not one of these authors has taken the trouble to see if the quan- tities of copper sulphate and arsenic trioxide taken would produce a salt of the formula given ; or have discovered the fact tiiat nearly twice as much potassium carbonate is used as is necessary to saturate the sulphuric trioxide of the copper sulphate, and Scheele's foot-note has been totallv ignored.

Secondly, Berzelius's account of the salt, which has evidently been misunderstood.

Thirdly, Bloxam's analyses of salts, which he would have found difficult, if not impossible, to reproduce, had he been so inclined.

After comparing the various works cited, it became a matter of in- terest to find out, in the first place, what Scheele's green really is, what are its properties, and whether there is more than one copper arsenite.

The experiment was tried of making copper arsenite according to the method given by Berzelius ; that is, by dissolving copper carbonate in an aqueous solution of arsenic trioxide.

Hydrocopper carbonate was prepared by precipitating copper sul- phate in the cold by an excess of sodium carbonate, and washing the precipitate with cold water until free from sulphates. Some of the precipitate was boiled with a saturated solution of arsenic trioxide, its blue color soon changed to a bright green, which it maintained, although boiled for upwards of an hour. The green i^recipitate was filtered off, and washed with hot water, until the wash waters were free from arsenic.

The substance remaining on the filter was of a bright sfreen color, scarcely inferior to Schweinfurth green in brilliancy, although of a vellowish shade.

16 PROCEEDINGS OF THE AMERICAN ACADEMY

The green precipitate was dried and analyzed, it gave, —

Al^ALYSIS No. I.

Per cents. Atomic Ratios.

Copper oxide, 66.02 8.31

Arsenic trioxide, 8.32 .42

Carbon dioxide, 15.26 3.47

Water, 10.33 5.74

99.93

This corresponds well with a mixture of dibasic carbonate and tribasic arsenite.

The brown basic carbonate produced by boiling the hydrocopper car- bonate with water was then boiled with arsenic trioxide, but was not changed in color. The filtrate from the green precipitate contained a large amount of arsenic, but was free from copper ; and I failed to obtain on evaporation the yellowish-green acid salt spoken of by Ber- zelius.

P'urther experiments on the carbonate were tried to see if it could be completely decomposed by boiling with excess of arsenic trioxide, but they all resulted in failure.

It seems to me that Berzelius must have been misled by the produc- tion of the brilliant green arsenio-carbonate, as he gives no analysis to support his assertion.

Arsenic trioxide seems to have a very strong influence in preventing the blackening of copper carbonates and hydrates, a very small per- centage preventing this well-known reaction.

A series of expei-iments were then tried on the production of Scheele's green, following the course laid down in the books and by Scheele himself; viz., first, the production of a more or less basic, sodium or potassium arsenite ; and, secondly, the addition of this to a solution of copper sulphate.

Experiment No. 1.

		Parts.	Atomic Ratios.
Copper sulphate.	CuS0,5H„0	50	2.04
Potassium carbonate.	K,C03	25	1.81
Arsenic trioxide.	As,03	10	.50

Dissolved the potassium carbonate in water, boiled and added the arsenic trioxide, filtered and added to the boiling solution of copper sul- phate. The precipitate, when washed and dried, was of a yellowish green; the filtrate was blue.

OF ARTS AND SCIENCES.

17

Analysis No. II.

Per cents.	Atomic Ratios.
Copper oxide, 56.98		7.18
Arsenic trioxide, 21.45		1.08
Sulphur trioxide, 12.80		1.60
Ferrous oxide, 1.60		.22
Water, 7.17		3.98
Experiment No. 2.	Parts.	Atomic Ratios.
Copper sulphate, CuSO^oH^O	50	2.04
Potassium carbonate, Kg^^s	30	2.17
Arsenic trioxide, AS2O3	15	.76

Treated as before ; filtrate pale blue, precipitate, a brighter green than No. 1.

Analysis No. III.

Per cents.	Atomic Ratios,
Copper oxide, 49.58	6.24
Arsenic trioxide, 32.12	1.62
Sulphur trioxide, 4.42	.55
Water, 13.88	7.82
Experiment No. 3.	Atomic Ratios.
CuSO,5H20, 50	2.04
K,C03, 40	2.90
As.,0„ 10	.50

Treated as before ; filtrate pale yellow, precipitate had more of a yellowish tinge than before.

Analysis No. IV.

Copper oxide, Arsenic trioxide, Sulphur trioxide. Water,

CuSO,5H20, K..CO3,

ASgOg,

VOL. XII. (n. 8. IV.)

Per cents.	Atomic Ratios,
51.26	6.43
31.67	1.60
5.32	.66
11.75	6.53
No. 4.
Parts.	Atomic Ratios.
50	2.04
50	3.61
18	.90

18 PROCEEDINGS OF THE AMERICAN ACADEMY

The potash and arsenic were dissolved and allowed to cool, then added to the cold solution of copper. The mixture effervesced strongly ; half of it was allowed to stand until next day, then filtered ; the other half was boiled, whicii operation it stood without blackening. Analysis of the first half gave, —

Analysis No. V.

	Per cents.	Atomic Ratios.
Copper oxide,	49.55	6.24
Arsenic trioxide,	38.90	1.96
Water,	11.55	6.42
The second half gave, —
Analysis N	0. VI.
	Per cents.	Atomic Ratios.
Copper oxide,	46.65	5.87
Arsenic trioxide.	42.94	2.17
Water,	10.41	5.78

Per c«iits.	Atomic Ratios.
51.40	6.47
39.57	1.99
8.72	■ 4.85

This preparation was repeated, using the same proportions ; the pre- cipitate was boiled, and washed with hot water until the filtrate was free from arsenic.

Analysis No. VII.

Copper oxide. Arsenic trioxide, Water,

This seems to indicate that either the salt is decomposed by washing with hot water, or that it consists of a strongly basic salt mixed with free arsenious acid. The first view is most likely the correct one, if we modify it so as to read : "it is decomposed by washing with either hot or cold water, forming a more basic salt."

But further experiments seem to show that this decomposition is much slower with cold tlian with hot water. And I have found it utterly impossible to remove the whole of the arsenic by prolonged washing.

This fact was further confirmed by an experiment of Prof. J. M. Ordway, who waslied a portion of the salt with 3,000 times its weight of water, without completely decomposing it. The basic salt produced by washing does not blacken on boiling with water, thus showing that we have a true basic salt or mixtures of several basic salts, and not a mixture of Bloxam's normal arsenite, HCuAsO^, and hydrate of copper.

OF ARTS AND SCIENCES.

19

Parts.	Atomic Ratios,
124.8	2.
49. .5	1.
53.	2.

Experiment No. 5.

In order to see if the salt IICu AsO^ could be prepared by taking the exact amount (if arsenic trioxide and copper sulphate necessary to form it, the following ^Jroportious were taken : —

Copper sulphate, Arsenic trioxide, Sodium carbonate,

The solution of arsenic in the sodium carbonate was boiled, and added, while boiling, to the solution of copper sulphate. And the ebullition was continued till all the carbonic aoid was driven off. The precipitate was washed by decantation once or twice, and then divided into three portions ; the first was merely drained, the second was washed a little, and the third was washed until arsenic ceased to be found in the wash-water. These portions were numbered respectively, VIIL, IX., X. They all contained basic copper sulphate, and No. VIII. probably contained a little sodium sulphate.

Analysis No. VIII.

	Per cents.	Atomic Ratios.
Copper oxide.	49.78	6.27
Arsenic trioxide.	35.93	1.80
Sulphur trioxide,	6.07	.76
Water,	7.56	4.20

99.34

Analysis No. IX.

	Per cents.	Atomic Ratios,
Copper oxide.	47.71	6.00
Arsenic oxide.	43.74	2.21
Sulphur trioxide,	3.10	.39
Water,	5.47	3.04

100.02

Analysis No. X.

	Per cents.	Atomic Ratios.
Copper oxide.	57.77	7.27
Arsenic oxide.	27.50	1.39
Sulphur trioxide,	5.27	.66
Water,	8.97	4.98

99.51

20 PROCEEDINGS OF THE AMERICAN ACADEMY

None of the above blackened on boiling with water, and all gave a blue solution with ammonia. Nos. VIII., IX. closely approximate a mixture of tribasic sulphate with Bloxam's salt; while No. X. is more basic than the formula for triarsenite calls for.

Experiment No. 6.

Molecules.

Copper sulphate, 6

Sodic carbonate, 3

Arsenic trioxide, 1

The filtrate was blue and acid ; the precipitate gave, —

Analysis No. XL

	Per cents.	Atomic Ratios.
Copper oxide.	60.80	7.66
Arsenic trioxide,	14.53	.73
Sulphur trioxide.	13.34	1.67
Water,	11.11	6.17

This corresponds with a mixture of tribasic arsenite and sulphate, with a little excess of copper oxide.

To the blue filtrate from the above, three molecules more of sodic carbonate were added, the filtrate was faint yellow, and free from copper, but contained arsenic; the precipitate contained a little car- bonate.

Analysis No. XII.

	Per cents.	Atomic RatioSc
Copper oxide.	56.71	7.14
Arsenic trioxide.	28.62	1.44
Sulpliur trioxide,	1.59	.20
Water,	9.50	5.28
Carbon dioxide,	.3.35	.77

99.77

These precipitates both dissolved in ammonia with a blue color, and stood boiling without change of color.

Experiment No. 7.

Molecules.

Copper sulphate, 6

Potassium carbonate, 6

Arsenic trioxide, 1

OP ARTS AND SCIENCES. 21

Boiled for half an hour, filtrate colorless, free from copper, but con- tained arsenic ; precipitate did not blacken on boiling, was free from carbonates, but contained basic sulphate. Washed until filtrate was free from arsenic.

Analysis No. XIII.

	Per cents.	Atomic Ratios.
Copper oxide,	58.85	7.41
Arsenic trioxide,	27.08	1.37
Sulphur trioxide,	4.83	.60
Water,	8.55	4.75

99.30

Experiment No. 8.

Scheele's orijrinal receipt is very nearly one part by weight ot arsenic to three each of copper sulphate and potassium carbonate, and is frequently so given. The proportions as given by Scheele are, eleven ounces of the first, and thirty-two of each of the otiiers. In molecules, supposing the potassium carbonate to be pure and anhydrous, as he directs it should be, the receipt will be as follows : —

As A, 1-

CuO, 2.32

ICCOg, 4.34

Or nearly double the amount of potassium carbonate required in the

CuSO, + IVjCOg = CuCOg + K,SO,.

A portion was, therefore prepared, using

Parts. Molecules. Copper sulphate 6 2.35

Potassium carbonate, 3 2.17

Arsenic trioxide, 2 1.

The filtrate was slightly acid and blue, but the potassium carbonate used not quite anhydrous. The color produced was fully equal to that produced by the oi-diuary receipt. The filtrate contained arsenic.

Analysis No. XIV.

	Per cents.	Atomic Ratios.
Copper oxide,	51.37	6.62
Arsenic trioxide,	39.94	2.02
Sulphur trioxide,	1.80	.22
Water,	6.61	3.67

22 PROCEEDINGS OF THE AMERICAN ACADEMY

This is an almost exact mixture of tribasic sulphate and arsenite. It dissolved in ammonia with a blue color, and did not blacken on boil- ing. Tlie potassium carbonate may, therefore, be considerably dimin- ished from that called lor in Scheele's receipt.

Experiment No. 9.

This was nearly a repetition of Experiment No. 4 as to quantities used. The object being in this case to study more iully tlie effects of washing, the proportions taken approximate closely to Scheele's receipt : —

Copper sulpliate, Arseuic trioxide, Potassic carbonate,

The solutions were mixed and boiled for half an hour; the first (No. XV.) was washed until the wash-water was free from sulphates; the other (No. XVI.) until the wash- water was free from arsenic.

Analysis No. XV.

Parts.	Molecules.
3	2.35
1	1.
3	4.34

	Per cents.	Atomic Ratios,
Copper oxide,	52.23	G.60
Ar.-ienic trioxide.	35.41	1.79
Sulphur trioxide,	5.88	.74
Water,	6.02	8.35

99.54 Analysis No. XVI.

	Per cents.	Atomic Ratioa,
Copper oxide,	57.18	7.20
Arsenic trioxide,	25.(32	\.m
Sulphur trioxide,	6.31	.79
Water,	10.85	3.90

'Experiment No. 10.

This preparation was made exactly according to Scheele's own direc- tions, as given by himself in the Proceedings of the Stockholm Academy, using the English translation for the weights and measures. The sample was divided after precipitation. No. XVII. was washed by decantation with the amount of water he specifies.

No. XVIII. was first boiled with water, and then washed with hot water so long as arsenic was found in the filtrate. The proportions used were, —

OF ARTS AND SCIENCES. 23

Parts. Arsenic trioxide, 11

Potassium carbouate, 32

Dissolved the potassium carbonate in thirty-two parts of water, added the arsenic trioxide boiled and filtered.

Parts.

Copper sulphate crystallized, 32

Water, 192

Dissolved and boiled while hot ; added, with constant stirring, the hot solution of arsenic trioxide.

Analysis No. XVII.

	Per cents.	Atomic Ratios.
		Found.	Taken.
Copper oxide,	50.76	3.10	2.32
Arsenic trioxide.	40.82	1.00	1.
Sulphur trioxide,	1.63	.10
Water,	6.41	1.75

99.62 Analysis No. XVIII.

	Per cents.	Atomic Ratios,
Copper oxide.	49.25	6.20
Arsenic trioxide.	42.66	2.15
Sulphur trioxide.	.42	.05
Water,	6.71	3.72

99.04

In summing up, I will first call attention to the fact that in no one of the eighteen samples does the arsenic exist in these compounds in as great a ratio as required by Bloxam's formula. Further, they all contain water, and this water is not driven off at a temperature of 150° C. In every case, arsenic was found in the filtrate, sometimes in considerable amount, as is shown by comparison of the ratios of copper sulphate and arsenic trioxide taken, and the ratios between the copper oxide and arsenic, as found in the analysis. All the samples dissolved in ammonia with a blue color.

In Experiments Nos. 4, 9, and 10 almost identical amounts of sub* stances were taken ; but the results, as will be seen, ditl'er widely.

Scheele's green may, accoiding to my experiments, be described as a

24 PROCEEDINGS OP THE AMERICAN ACADEMY

more or less basic copper arsenite, which may or may not contain basic copper sulphate and carbonate ; the composition of it seeming to de- pend to a considerable extent upon the degree of concentration of the liquid from which it is precipitated. Its basicity also seems to depend to a considerable extent upon the same fact, the more dilute the solu- tion the more basic tlie salt.

The composition also depends, to some extent, on the amount of wash-water used in washing it.

The normal pi<fment which is represented by Analysis XVIII. may be described as follows : —

It is of a yellowish green color, soluble in dilute acids and in caustic alkalies. It dissolves in alkalies with a blue color, and is decomposed by excess of soda or potassa, or their carbonates, but is not decom- posed by ammonia, even upon boiling. It does not blacken upon boiling with distilled water. When dissolved in ammonia, if a solu- tion of soda or potash is added, the solution is bleached, from the reduction of the copper salt to a cuprous salt.

Its average composition, as generally prepared, omitting the sulphur trioxide which is generally found in it, is about as follows : —

Copper oxide,	50.00
Arsenic trioxide,	42.00
Water,	8.00

This approximates closely to the formula,

Cu3As20,2Il20.

This formula would give the following percentages : —

Copper oxide.	51.44
Arsenic trioxide.	41.93
Water,	7.93

Taking this view of the subject, Scheele's green is the normal tri- cupric arsenite, and corresponds to the triargentic arsenite described by Bloxam.

It is almost impossible, however, to obtain a perfectly constant prod- uct, from the strong tendency to form basic sulphates and basic arsenites.

As a matter of economy in the preparation, it will be found more advantageous to take the following proportions rather than those given by Scheele : -

OF ARTS AND SCIENCES. 25

Parts. Copper sulphate, 6

Arsenic trioxide, 2

Sodium carbonate, Na^CO3l0H2O, 8

Dissolve the soda and arsenic in ten parts of water, and the copper sulphate in forty parts of water ; filter botli solutions if necessary. Mix while boiling, boil for a few minutes, and then allow to stand until next day ; pour off the supernatant licjuid, fill up the vessel with hot water ; repeat this operation about three times, then filter, and dry at about 100° C.

In analyzing these salts, the water was determined by ignition in a current of oxygen. The water being collected and weighed in a chloride of calcium tube. The arsenic was determined in various ways, but it was found that the conversion into arsenic pentoxide and trituration with uranium solution gave the most satisfactory results. The copper was determined with the battery.

The separation of copper and arsenic was made either by boiling with a slight excess of potassa with previous oxidation by nitric acid or bromine, or by adding potassa, and then passing hydrogen sulphide through the solution until the copper was completely precipitated.

My thanks are due to my assistant, E. R. Hills, for the able manner in which he has aided me by making many analyses of these salts, — an undertaking that can be appreciated only by those who have tried working with copper and arsenic in combination.

Since the above paper was finished, I have succeeded in obtaining two samples of copper arsenite as found in commerce. The first of these resembled closely that analyzed in Analysis No. XII. in color, and on examination it was found to contain carbon dioxide and sul- phur trioxide ; the other resembled Analysis No. XVIII., and, like it, contained a trace of sulphate.

Boston, June 1st.

26 PROCEEDINGS OF THE AMERICAN ACADEMY

III.

CONTRIBUTIONS FROM THE CHEMICAL LABORATORY OF

HARVARD COLLEGE.

I.— ON THE ETHERS OF URIC ACID. By H. B. Hill.

{First Paper.) Presented, June 14, 1876.

Although the constitution of many of the derivatives of uric acid may be said to be fairly established, the structure of uric acid itself is still a matter of conjee-ture. The formulae given by Baeyer,* Kolbe,t Streckert Erlenmeyer, § Mulder, || Hiifner, T[ Gibbs, ** Medicus, ft Drechsel, tt and Mallet ; §§ differing, as they do, in points more or less essential, show that the experimental data are as yet insufficient to estab- lish its structure. In this connection the ethers of uric acid seem to have attracted little attention. In 1864, Dryjiin |{|| prepared the diethyl and triethyl ethers by the action of ethyl iodide upon diplumbic urate. I have been unable to obtain the original paper, but from the summary of it given in the Jahresbericht HH for that year, and in Gmelin's*** hand-book, it would appear that he submitted them to no very ex- tended examination. I have, therefore, undertaken the study of the ethers of uric acid, with the hope that a careful study of the products

* Ann. Chem. u. Pliarm., 127, 235.

t Journ. fiir prakt. Chem. [2] 1. 134. Berichte, Deutsch. Chem. Gesellsch. III. 183.

J Zeitsehr. fUr Chem. 1868, 863.

§ Zeitsehr. fur Chem. 1869, 176. Munchen. Acad. Ber. 2, 276.

II Bericht. der Deutsch. Cliem. Gesellsch. VL 1237.

t Journ. fur prakt. Chem. [2J 3, 23.

** Amn. Journ. [2] 46, 289.

tt Ann. Chem u. Pharm. 175, 243.

tt Chem. Centralbl. 1875, 493.

§§ Amn. Journ. Mch. 1876, 195.

nil Russ. Zeitsehr. Pharm. ii. 3, 28, 49, 113, 121.

IT Jahresbericht. 1864, 629.

*** Gmelin, Suppl. ii. 1026.

OF ARTS AND SCIENCES. 27

of their decomposition may throw additional light upon the structure of uric aci(i.

A few preliminary experiments convinced me that the compounds in the methyl series could be much more conveniently made than those of the ethyl or benzyl. I tlierefore began with the methyl ethers, and this paper gives tl^^ results I have obtained in the study of the first of these.

Methyhiric acid, C-H3(CH3)N^03.

Methyluric acid may readily be prepared by the action of methyl iodide upon monoplurabic urate. The metathesis takes place slowly at 110°-130°, rapidly between 160° and 165°. The dry lead salt mixed with methyl iodide in molecular proportions, enough ether being added to keep the mixture fluid, is heated in sealed tubes for eighteen hours at 165°. After tlie evaporation of the ether, the product of the reaction is boiled with water, and the solution filtered from the un- altered plumbic urate. The lead is then precipitated with hydric sulpliide, and the plumbic sulphide filtered off boiling hot. The filtrate deposits, on cooling, meihyluric acid in small crystals. Tliese are dissolved in dilute potassic hydrate, the solution boiled for a ^evf minutes, reprecipitated by hydrochloric acid, and recr}stallized from boiling water. The yield is about 60 f^ of the amount theoretically required by the lead salt which enters into the reaction. 220 grms. plumbic urate gave 54 grms. methyluric acid, and 89 grms. of unaltered lead salt. Afterwards, in working up the recovered lead salt, which was much more compact in form than the salt originally employed, I found the decomposition almost complete. In this case 100 grms. lead salt gave me 41 grms. methyluric acid. A portion of the uric acid is completely decomposed, and is found as ammonium salt in the mother liquors and the crude product. I attempted to increase the yield by employing anhydrous ether in the place of common ether. Although no ammonium compounds were then formed, a much smaller percent- age of the lead salt entered into reaction. Longer heating at a .ewer temperature did not increase the yield, inasmuch as a larger quantity of dimethyl ether was then formed. The amount of dimethyl ether formed by heating to 16.)° is small; and as it is much more soluble in water than the monomethyl ether, it may readily be removed by re- crystallization.

Methyluric acid crystallizes in small clear flat prisms, apparently of the triraetric system, the crystals being often pointed at either end. By slow cooling of a dilute solution, these crystals sometimes reach a

28 PROCEEDINGS OF THE AMERICAN ACADEMY

length of 2-3 mm., but they are usually much smaller. The substance undergoes no visible change when heated to about 300° ; at a higher temperature, it melts with complete decomposition, and without per- ceptible sublimation. It is soluble in boiling water, almost insoluble in cold water or in boiling alcohol ; insoluble in ether. Cold concen- trated sulphuric acid dissolves it abundantly ; upon dilution it crystal- lizes out, apparently unchanged. Air-dried it contains water, a portion of which it loses at 100° ; the rest slowly, but completely, at 160°.

1.3887 grm. substance air-dried lost at 165° 0.1124 grm. = 8.09%.

The formula C5H3(CH3)N^03 . Hp requires 9.00%. Of substance dried at 100°: —

1. 0.7772 grm. lost at 165° 0.0399 grm. = 5.13 %.

2. 0.4953 „ „ 0.0289 „ = 5.83 %.

3. 0.4670 „ „ 0.0238 „ = 5.10 %.

4. 0.8106 „ „ 0.0451 „ = 5.57 %.

The formula C5H3(Cri3)N,03 . iHp requires 4.77 %.

from these determinations, it would appear that water is not a definite constituent of the compound. The microscopic appearance of the substance remains unchanged.

The substance dried at 165° has the formula 05113(0 H3)N^03, as the following analyses show: —

1. 0.4284 grm. gave 0.1310 grm. 11,0, and 0.6210 grm. OO2.

2. 0.2748 grm. gave 0.0985 grm. II.p, and 0.3972 grm. OO2.

3. 0.1822 grm. gave 50.0 cc. nitrogen, at 20°.o, and 754.3 mm. pressure.

Calculated for Found.

0,H,N,03. 1 2 3

0 39.56 39.53 39.43

H 3.30 3.39 3.98

N 30.77 30.98

To determine the solubility in boiling water, a boiling saturated solution was filtered through a hot, water filter into tared fiasks. After cooling, the flasks were weighed, the contents washed out, evaporated in platinum, and the residue dried at 165°.

1. 52.290 grm. solution left 0.2043 grm. residue.

2. 55.379 grm. solution left 0.2187 grm. residue.

The boiling saturated solution contains, therefore, the percentages, — 1 2

0.3906 0.3950

OF ARTS AND SCIENCES. 29

A boiling solution was allowed to stand overnight at a temperature of about 20°. For three hours before tiltering. it was kept at 20°, with constant stirring. Portions of the filtered solution were weighed, evaporated, and the residue dried at lo5°, —

1. 39.020 grm. solution gave 0.0083 grm. residue.

2. 49.854 grm. solution gave 0.0111 grm. residue.

The solution saturated at 20° contained, therefore, in percentages, —

1 2

0.0213 0.0223

As the mean of these determinations, we find that there is required for the solution of one part of methyluric acid 253.6 parts of boiling water, and 4596 parts of water at 2(1°.

The aqueous solution reddens litmus feebly, and decomposes car- bonates readily on heating. A solution in potassic or sodic hydrate is not precipitated by carbonic dioxide. From a concentrated cold solu- tion, stronger acids precipitate it gelatinous, from hot or dilute solutions crystalline.

With bases metliyluric acid forms a series of definite salts, some of which have been studied by Mr. O. R. Jackson in this laboi-atory. The results of this investigation he presents to the Academy in a separate communication. He has shown tliat the monomethyl ether of uric acid is itself a dibasic acid, like uric acid; a fact which is certainly remarkable, and of obvious theoretical importance.

Action of Hydrochloric Acid.

In 1867, Streeker* showed that uric acid heated with fuming hydro- chloric or liydriodic acid to 170° assimilates five molecules of water, giving carbonic dioxide, ammonia, and glycocoll, —

C,H,X,03 + 5H,0 = 3C0, + 3NH3 + C,H,NO,.

The inferences which he drew f from this reaction concerning the structure of uric acid are well known. Emmerling$ has I'ecently shown that cyanogen gas passed into boiling hydriodic acid is converted into glycocoll, and seeks thus to give Strecker's reaction a new interpre- tation. In either case, however, it seemed to me of importance to

* Ann. Cliem. u. Pliarm. 146, 142; Zeitschr. fur Chem. 1868, 215.

t Zeitschr. fiir Cliem. 1868, 363.

t Bericlite Deutsch. Cliem. Gesellsch. VI. 1351.

30 PROCEEDINGS OF THE AMERICAN ACADEMY

determine the products of the decomposition of methyhiric acid under these conditions.

Two tubes, each containing 1.3 grm. methyluric acid, and an excess of hydrochloric acid saturated at 0°, were heated four or five hours at 170'^. The gas wliich escaped on opening the tubes was found to con- tain no methyl chloride. The excess of acid was driven off on the water bath, and the residue distilled with plumbic hydrate until the distillate was no longer alkaline. The ammoniacal distillate was caught in hydrochloric acid, and evaporated to dryness on the water bath. The residue was treated with a small (juantity of absolute alcohol, and the filtered solution again evaporated to dryness. There was then left a white saline residue, wliich gave with great readiness Hofmaiin's iso- cyanide reaction, showing the presence of a monamine. The chloride was converted into the platinum salt, and this was analyzed after re- crystallization from hot water.

0.4760 grm. gave on ignition 0.1991 grm. platinum.

Calculated for Found.

. (CH3NH,).PtClg Pt 41.61 41.82

Methylamine is, therefore, one of the products of the reaction.

From the residue left on distillation, it was easy to isolate glycocoll in the ordinary way. The licjuid was filtered from the basic [dumbic chloride, the lead removed from the solution by hydric sulphide, and the filtrated evaporated. On standing, glycocoll crystallized out with its characteristic properties. For its identification, it was converted into the copper salt by boiling with freshly precipitated cupric oxide, and precipitation of the blue solution by alcohol. Of this salt, —

0.4400 grm. lost at 130° 0.0388 grm.

Calculated for Found.

(C2H,N0,)_,Cu . li.fi Bfi 7.85 7.68

A determination of copper in the dry salt gave, —

0.4068 grm. left on ignition 0.1523 grm. CuO.

Calculated for Found.

(C,H,NO,),Cu CuO 37.00 37.43

The reaction in this case may therefore be writtten, —

C,H3(CH3) N,03 + 5 H,0 = 3C0, + 2NH3 + CH.NH, + CJI.NO,.

OF ARTS AND SCIENCES. 31

It will be seen that this reaction proves the commonly accepted view that uric acid is not an hydroxyl but an iniid acid.

In order further to establish tlie relative position of the methyl radical, it seemed to me of chief importance to follow it through oxida- tion in alkaline and acid solution, and thus determine its relation to allantoin and alloxan or paraban.

Methylallantoin. C^H. (CHg) N^^.

Methyluric acid is readily oxidized in alkaline solution, according to the metliod of Claus and Emde.* The .solution must be dilute with but a small excess of alkali, the potassic permanganate added slowly in exact molecular proportion. As soon as the manganese dioxide has separated, it must be filtered rapidly with the aid of the pump, and the filtrate slightly acidified with acetic acid. I then found it most ad- vantageous to evaporate as quickly as possible on the water bath to small volume. After standing twenty-four hours, the methylallantoin crystallizes out in clusters of radiated prisms. These separated from the mother liquor by pressure, and recrystallized several times from hot water, form clear distinct monoclinic prisms, closely resembling ordinary allantoin. They are readily soluble in hot water, sparingly in cold ; almost insoluble in alcohol, hot or cold, and insoluble in ether. These crystals melt with decomposition at 225°.

In spite of many variations of the method, I could obtain in this way but fifteen per cent of the theoretical yield. From the mother liquors evaporated to a syrup, alcohol separates a potash salt, probably of methylallantoic acid. On account of its uninviting character it was not further examined.

Methylallantoin dried at 100° gave, on analysis, —

0.23G2 grm. gave 0.1092 grm. 11,0, and 0.2978 grra. COg.

Calculated for Found.

C,H,(CIl3)NA. C 34.89 34.39

H 4.65 5.13

Silver nitrate gives in a hot saturated solution on the cautious addi- tion of ammonic hydrate, a crystalline precipitate consisting of needles or short prisms. This salt is readily soluble in hot water, more sparing'y in cold. By spontaneous evaporation of the cold solution,

* Bericlite Deutsch. Chera. Gesellsch. VII. 226.

32 PROCEEDINGS OF THE AMERICAN ACADEMY

tolerably perfect crystals of the trimetric system were obtained. This compound may be dried, without decomposition, at 100°, and gave then OQ analysis, —

0.1668 grm. left on ignition 0.0646 grm. silver.

Calculated for Found.

AgC,II,(CIl3)N,03. Ag 38.71 38.61

Baeyer * has shown that allantoin, when heated with hydriodic acid, breaks up into urea and hydantoin ; and it was evident that methyl- allantoin should give an analogous reaction. I therefore heated methylallantoin with concentrated hydriodic acid, following the direc- tions given by Baeyer.t When the reaction appeared to be ended, the liberated iodine was reduced with sulphide of hydrogen, and the hydriodic acid removed by plumbic carbonate. The filtrate gave on evaporation, after standing for some time, clear crystals, which, freed from the syrupy mother liquor, and recrystallized from water, formed transparent prisms, readily soluble in water or alcohol, and giving no precipitate with zincic chloride. Ti)eir melting point I found to be 144°-145°. The quantity at my disposal was insufficient for analysis, but there can be no doubt of the identity of this substance with methyl hydantoiu described by Neubauer t as resulting from the action of baric hydrate upon creatinine, inasmuch as he gives these properties and the melting point 145'^. The reaction may, therefore, be written, —

CH3

/

C,H,(CH3)N,03 + H, = Co' + Co''

\ \

NH^ NH— CO

Once, as the action of the hydi-iodic acid was longer continued, I obtained a substance crystallizing in broad rhombic plates, readily soluble in water, sparingly soluble in alcohol, wlii^h gave a precipitate with an alcoholic soUition of zincic chloride. These crystals melted at 10,5°, and sublimed readily at 100°. They were evidently sarcosine formed from the decomposition of methylliydantoin.

* Ann. Chem. u. Plmrm. 117, 178. t Ann. Cliera. u. Pharm. 130, 158. } Ann Chem. u. Pharm. 137, 288.

OP ARTS AND SCIENCES. 33

Oxidation of methyluric acid with nitric acid.

By the oxidation of methyluric acid with nitric acid, a solution is obtained which gives a deep red coloration on wanning with amnionic hydrate. From this solution, however, I have as yet been unable to isolate a crystalline product. By spontaneous evaporation in the air, a sticky syrup is obtained, which does not solidify, even after long standing in vacuo over sulphuric acid. Alcohol dissolves this residue, the solution remains clear after the addition of ether, and on evaporation again leaves an uncrystallizable syrup. I have been equally unsuccess- ful in separating by stannous chloride or sulphide of hydrogen a crystalline alloxantine or dialuric acid. Oxidation with potassic chlorate and hydrochloric acid, according to the method of Schlieper,* gave the same result. These reactions were sufficient to give a quali- tative proof tliat the solution did not contain ordinary alloxan. I therefore attem(»ted to prepare from this solution a methylalloxanate in form fit for analysis. I first tried with baric hydrate, to form the barium salt. The ordinary method, following closely the directions of Schlieper, f gave me, however, a salt containing but a trace of nitrogen and with percentages of barium, carbon, and hydrogen, closely approximating those required by a basic baric mesoxalate, BaCgO^.BaO^H^. At the same time a strong smell of methylamine was perceived. If a smaller quantity of baric hydrate were added in the cold, and then alcohol in excess, a barium salt was thrown down which contained nitrogen, but it could not in this way be obtained of constant cumposition. Plumbic hydrate seemed to determine the for^ mation of the methylalloxanate, but no better results were obtained. The silver salt blackened too rapidly to admit of analysis.

The lime salt is the only one I have been able to prepare with con- stant composition. Methyluric acid is dissolved in as small a quantity of nitric acid of 1.42 sp. gr. as possible, the solution somewliat diluted, and the excess of acid neutralized with calcic carbonate in the cold. The solution is tiien allowed to stand in vacuo for some time, to free it from carbonic dioxide, afterwards diluted with six or eight volumes of alcohol and filtered. The cautious addition of amnionic hydrate to the filtrate throws down a bulky semigelatinous precipitate, wiiich, well washed with alcohol, and dried at 100°, forms an amorphous powder, which has a faint pink color, — undoubtedly caused by a trace of alloxan. The dry salt was soluble in cold water, though with some difficulty.

* Ann. Cliem. u. Pharm. 55, 2G1. t Ann. Chem. u. Pharui. 55, 212. TOL. XII. (n. S. IV.) 3

34 PROCEEDINGS OF THE AMERICAN ACADEMY

Analysis gave for substance dried at 100°, —

1. 0.1778 grm. gave 0.1125 gnu. CaSO^.

2. 0.2275 grm. gave 0.1446 grm. CaSO,.

3. 0.3049 grm. gave 36.8 cc, nitrogen at 21°.5, and 762.1 mm. pressure.

Calculated for Found.

CJI(CH3)N20,Ca 1 2 3

Ca 18.87 18.61 18.69

N 13.21 13.68

The analyses 1 and 2 were made with different preparations.

If ammouic hydrate be first added, and the calcic salt then precipi- tated by alcohol, the salt contains too little nitrogen A sample prepared in this way gave, on analysis, 20.88 % Ca, and 10.75 % N. So also if the precipitate thrown down by ammonic hydrate in alcoholic solution be dissolved in water, and reprecipitated by alcohol, the per- centage of calcium is increased, and the nitrogen diminished. Analysis gave 20.49 % Ca.

Inasmuch as the chief point was to prove the formation of methyl- alloxan by this oxidation, I distilled the calcium salt, prepared in the manner described, with potassic hydrate in a current of steam. The ammoniacal distillate readily gave the characteristic isocyanide reaction by heating with alcoholic potash and chloroform. It was neutralized ■with hydrochloric acid, evaporated, and from the residue the methyl- amine chloride separated by absolute alcohol. An analysis of the platinum salt gave —

0.2160 grm. left on ignition 0.0902 grm. platinum.

Calculated for Found.

(CH^Nig.PtCl,

Pt 41.61 41.76.

Thus proving that the calcium salt contained the group = N — CH^ . lu further confirmation, I was able to isolate common urea as the secondary product of the methylalloxan formation. After oxidizing with hydrochloric acid and potassic chlorate, the excess of acid was driven off by evaporation at gentle heat, the potassic chloride separated with absolute alcohol, and the alcoliolic solution evaporated to a syrup. The cautious addition of strong nitric acid caused the separation of abundant crystals of urea nitrate in characteristic form. The base, set free as usual with baric carbonate, after recrystallization from water, melted at 129°-130'>.

OP ARTS AND SCIENCES. 35

The reaction may, therefore, be written : —

CH3

/

NHjj N — CO

/ / I

C,H,(CH3)N,03 + H,0, = CO + CO CO

\ \ I

NH2 NH— CO

Methyl paraban, C3lI(CIl3)N203.

Although methylalloxan is so unstable in the presence of bases, in acid solution it possesses remarkable stability. It may be boiled for some time with strong nitric acid, or with hydrochloric acid aud potassic clilurate before tbe red coloration with ammonia disappears. On prolonged boiling (about an hour) with strong nitric acid, the oxidation is complete, and the solution contains methylparaban. For its preparation I have found it most advantageous to boil methyluric acid with five or six parts of nitric acid of sp. gr, 1.3, until a drop taken out fjives no coloration with ammonia. The excess of acid is then driven off on the water bath, the syrupy residue diluted with a little water, and well shaken out with ether. On distilling off the ether, a syrup remains which soon crj'stallizes in shining radiated prisms, which are recrystallized from hot water. Thej are somewhat difficultly soluble in cold water, readily in hot ; soluble in alcohol and ether. The substance melts at 149°. 5, sublimes very slowly at 100°, and at higher temperature with great readiness. For analysis, the air-dried substance was heated three hours at 100° ; duriug that time 0.2260 grm. lost 0.0030 grm.

1. 0.1714 grm. gave 0.2333 grm. CO2. *

2. 0.2160 grm. gave 0.0785 grm. H,0, and 0.2629 grm. COg.

Found.

1 2

37.12 37.48

4.04

The substance gives no precipitate with calcic chloride, even after the addition of ammonic hydrate. On warming the ammoniacal solu- tion, a precipitate falls not wholly soluble in acetic acid. Argen- tic nitrate precipitates it only in concentrated solution. The silver salt prepared from concentrated solution, wnth the cautious addition of

* The hydrogen in this analysis was lost.

	Calculated for
	C,N,H,03
C	37.50
H	3.13

36 PROCEEDINGS OF THE AMERICAN ACADEMY

ammonic hydrate, crystallizes in prismatic needles ; quite readily solu- ble in hot water, sparingly in cold. Under the microscope it crystal- lizes from hot aqueous solution in rhombic plates. It may be dried at 100° without decomposition. It gave on analysis, —

0.1210 grm. left on ignition 0.0056 grm. silver.

Calculated for Found.

AgC,N,Il303. As 45.95 45.95

There can be no doubt that this substance is identical with that obtained by Dessaigiies* from creatinine, which was first recognized by Strecker f as methylparaban. Dessaignes gives no melting point, but the description given corresponds peifectly with the substance I have obtained ; the only diiference being that I find the substance quite readily soluble in ether, whereas he gives it as somewhat soluble only.

A consideration of the bearing of these facts upon the structure of uiic acid I shall postpone until I have obtained further results.

n. — ON SOME OF THE SALTS OF METIIYLURIC ACID,

C^HstCHsJN.Og.

By Oscar R. Jackson.

Presented, June 14, 1876.

This work was undertaken with the purpose of proving the basicity of methyluric acid. The acid was obtained by the method described by Prof. 11. B. Hill, under whose direction the preparation and analyses of the salts were conducted.

Owing to the fact that all the dibasic salts absorb carbonic acid very readily when exposed to air, as is the case with the salts of uric acid, special means had to be taken to dry the salts in an atmosphere free from carbonic acid. For this purpose they were dried in vacuo over sulphuric acid, and a few pieces of potassic hydrate were also placed under the receiver when the dibasic salts were dried. For the de- termination of the water of crystallization, the salts were heated to

* Ann. Chem. u. Pharm. 97, 343. t Ann. Chem. u. Pharm. 118, 164.

OF ARTS AND SCIENCES. 37

140° to 150° in a current of air ; the air being first caused to pass tlirough a series of six tubes, each 2. J feet long; two being filled with solid potassic hydrate, and the remaining four with calcic chloride. The substance being weigiied before and after heating, the water was estimated by the loss of weight. The bases were then estimated in the anhydrous salts by the methods given below.

Dipotassic methylurate, K2CJI(CH3)N^03 . 311^0.

This salt was made by suspending about one gramme of the acid in ten or fifteen cubic centimetres of boiling water in a small flask, and then adding a solution of potassic hydrate in large excess over the amount necessary to dissolve the acid. The solution was then boiled for some time, and about 100 cc. of alcohol added. On the addition of tlie alcohol, the salt separates out in a flocculent form. The flask is then corked up, to avoid exposure to carbonic acid, and allowed to stand twenty-four hours. The precipitate is then filtered off rapidly by the Bunsen pump, washed with alcohol, and dried in vacuo over sulphuric acid and potassic hydrate.

This salt when dry is an amorphous flocculent substance, and is very soluble in hot water; but when a hot solution cools, the salt does not separate out, but becomes a gelatinous mass resembling glue. This salt absorbs carbonic acid very readily from the air. When carbonic acid is passed tlu-ough a solution of this salt, the monopotassic salt is probably formed, though no precipitate falls.

The water of crystallization was determined by the method given above. For the determination of the potassium, the anhydrous salt was ignited in a platinum crucible ; and, after the residue had been burned as white as possible, it was treated with a few drops of hydro- chloric acid. The excess of hydrochloric acid was then driven off, and the crucible ignited gently to avoid decrepitation, and then finally heated to dull redness for a few seconds.

0.3700 grm. of salt dried in vacuo gave 0.0635 grm. lip = 17.17 % Calculated for K^C^HCCiyN.Og . 311,0 = 17.29 %

0.4974 grm. of dried salt gave 0.2367 grm. KCl; K = 24.95 %

Calculated for K,C5H(CH3)N,03 = 25.04 %

Monopotassic methylurate, KCgTT2(CIl3)NP3 . 1\0.

This salt was made by suspending about one gramme of the acid in ten or fifteen centimetres of boiling water, and adding potassic carbon-

38 PROCEEDINGS OF THE AMERICAN ACADEMY

ate in slight excess over the calculated amount. The acid dissolves on the addition of the potassic carbonate with disengagement of carbonic acid. The solution was then boiled for some time, until the effervescence ceased, and precipitated with alcohol; allowed to stand twenty-four hours, filtered, washed with alcohol, and dried as in the case of the dipotassic salt.

This salt is quite like the dipotassic salt. It is very soluble in hot water, gelatinous on cooling, and is insoluble in alcohol.

The method of analysis was the same as for the dipotassic salt, with the exception that the potassium was estimated in the hydrous salt.

0.3161 grm. of salt di-ied in vacuo gave 0.0228 grm. H^O = 7.21 % Calculated for KCJi^CCHjjN.Oj.H.O = 7.56%

0.3766 grm. of salt dried wt7a(;Mo gave 0.1152 grm. KCl ; K= 16.01 % Calculated for KC5H2(CH3)N^03 . II^O = 16.42 %

Disodic methyhirate, Na,C5H(CIl3)NP3 . 3II2O.

This salt was made bv dissolving; the acid in an excess of sodic hydrate and precipitating with alcohol, exactly as in the case of the dipotassic salt, which it closely resembles.

The analysis was conducted in the same way as above.

0.6691 grm. of salt dried in vacuo gave 0.1287 grm. H^O = 19.23 % Calculated for Na2C5n(CH3)N,03 . 3H,0 = 19.28 %

0.4548 grm. dried salt gave 0.2304 grm. NaCl ; Na = 19.92 %

Calculated for Na2C5H(Cn3)N,03 = 20.35 %

Monosodlc methylurate, l^a.C^:l.XCYi^)l!ifi.^ . H2O.

This salt was made by adding, very carefully, a solution of Na.,SO^ to a boiling-hot solution of monobaric methylurate until there is no further precipitate of baric sulphate. The solution was then filtered from the BaSO^, evaporated to a very small quantity, and then pre- cipitated with a large amount of alcoljol 100 to 150 cc. ; allowed to stand twenty-fovtr hours, filtered, washed with alcohol, and dried in imcuo. This salt does not seem to be quite as gelatinous as the rest, and is much more soluble in dilute alcohol.

In the analysis of this salt the water was determined as above, and the sodium by ignition of the anhydrous salt, and treated with a few drops of sulphuric acid.

OF ARTS AND SCIENCES. 39

0.1944 grm. of salt dried in vacuo gave 0.0150 grm. H^O = 7.81 % Calculated forNaC,n,(CIl3)N,03. 11,0 = 8.10%

0.1790 grm. of dried salt gave 0.0G13 grm. Na^SO^; Na = 11.00 % Calculated for NaCJI.CCigN.Og = 11.27 %

Dibaric methylurate, BsLC^W^CR^^fi^ , S^HgO.

This salt was made by dissolving one gr. of the acid in as little boil- ing water as possible in a small flaj^k, and adding tweuty-Hve cc. of cold saturated solution of baric hydrate. The solution was then boiled for some time, corked up, and allowetl to stand. The salt separates out in very minute needles, clustered together in places, and of a slightly greenish tinge. The salt was collected on a filter, and washed rapidly with a very small quantity of cold water, and then dried in vacuo. The chief feature of this salt is, that it is the only one of the salts obtained which shows the slightest tendency to assume a crystal- line form. It is also the most insoluble of any of the salts.

The salt prepared in this way gave, in several analyses, too great a percentage of barium. It was found impossible to free it from the excess of baric hydrate by washing on account of the ready solubility of the salt.

The water was determined as before, and the barium by ignition o'f the anhydrous salt in a platinum crucible, and treatment with a little sulphuric acid. The excess of acid was driven off, and then the crucible heated for some time in a current of air to oxidize any sulphide which might have been formed.

o

1.2318 grm. salt dried in vacuo gave 0.1979 grm. H^O = 16.06 % Calculated for BaC,H(CH.)N,03 . 311120 = 16.57 %

0.4738 grm. dried salt gave 0.365G grm. BaSO^; Ba = 44.07 %

Calculated for BaC5H(CH3)N^03 = 43.22 %

3fonobaric methylurate, BaC5(H(CH3)N^03)2 • 4H2O.

For the preparation of this salt, about one gramme of the acid was suspended in boiling water, and baric carbonate added until no more would dissolve. The solution was then boiled for some time, and filtered from the undissolved baric carbonate, and precipitated by alcohol. On tiie addition of alcohol, it separates out as white powdei". It is very soluble in hot water, and solidifies on coolins: into a white jelly-like mass.

40 PROCEEDINGS OF THE AMERICAN ACADEMY

The analysis was made as in the case of the dibarium salt.

0.5073 <rrm. salt dried in vacuo gave 0.0G14 grm. H^O = 12.10 % Calculated for Ba (C5H(CH8)N,03) . 4H,0 = 12.60 %

0.4472 grm. dried salt gave 0.2109 grm. BaSO, ; Ba = 27.73 % Calculated for Ba(C5H(Cn3)N,Oj2 = 27.45 %

Monocaldc methylurate, Ca(C.H(CH.j)NP8)2 • 3HoO.

This salt was made from calcic carbonate in the same manner as the monobarium salt, except that it was found necessary to boil the acid with the carbonate for several hours, in order to ensure the complete conversion of the acid.

This salt has nearly the same properties as tlie monobarium salt. It is a grayish substance, very soluble in hot water, and gelatinizes on cooling.

The analysis was conducted as in the case of the barium salts.

0.2123 grm. salt dried in vacuo gave 0.0244 grm. H^O = 11.49 % Calculated for Ca(C5lI(CH3)N,03)2 . 411^0 " = 11.89 %

0.1864 grm. of dried salt gave 0.0600 grm. CaSO^ ; Ca = 9.43 % Calculated for Ca(C5H(CH3)N,03)2 = 9.95 %

A dicalcium salt has been obtained by the action of methyluric acid on calcic hydrate, but has not yet been analyzed.

The action of methyluric acid on plumbic carbonate was tried with expectation of obtaining a lead salt, but the reaction does not seem to work easily, for though carbonic acid is evolved, and sulphide of hydrogen gives a slight precipitate with the filtrate, still the salt which separates out on cooling does not seem to be homogeneous, and on analysis gives but a very small percentage of lead. It probably con- sists of tlie free acid with a small amount of lead salt.

We thus see that there are two distinct sets of salts, and it is evident that methyluric acid is dibasic, — a fact of considerable theoretical in- terest, inasmuch as uric acid only forms two sets of salts, and not without some bearing on the constitution of uric acid.

Before closing. I wish to express my sincere thanks to Prof. IL B. Ilill for his valuable advice, and for the kind interest which he has taken in the progress of this work.

OF ARTS AND SCIENCES. 41

IV.

CONTRIBUTIONS FROM THE PHYSICAL LABORATORY OF THE MASSACHUSETTS INSTITUTE OF TECHNOLOGY.

XL ON THE EFFECT OF TEMPERATURE ON THE VISCOSITY

OF AIR.

By Silas W. Holman.

Read, June 14, 1876.

The developments of the "kinetic theory" of gases made within the last ten years have enabled it to account satisfactorily for many of the laws of gases. The mathematical deductions of Clausius, Maxwell and others, based upon the hypothesis of a gas composed of molecules acting upon each other at impact like perfectly elastic spheres, have furnished expressions for the laws of its elasticity, viscosity, conduc- tivity for heat, ditfusive power and other properties. For some of these laws we have experimental data of value in testing the validity of these deductions and assumptions. Next to the elasticity, perhaps the phenomena of the viscosity of gases are best adapted to investigation.

According to the kinetic theory, the molecules of the gas are con- stantly in rectilinear motion. In virtue of their mass and velocity, these molecules have a certain momentum. Hence, if we have two layers of air moving over each other, we shall have a mutual inter- change of momentum from the transference of molecules from one layer to another, the result being a tendency toward an equalization of the velocities of the two layers. This produces the effect of friction between the two layers, and its amount determines the viscosity of the gas in any particular case. From analytical considerations Maxwell has deduced * an expression which, as corrected by Clausius,t should

read,

_ Mu

where j/ is the coefficient of viscosity of any gas ; Mis the mass of a mole- cule ; u the "velocity of mean square " of the molecules ; and s thedis-

* Pliil. Mag. xix., xx.; 1860. t Phil. Mag. xix., 434.

42 PROCEEDINGS OF THE AMERICAN ACADEMY

tance between the centres of two molecules at impact. The value of t] is expressed in units of length, mass and time, since it is a tatigentifJ force. This formula, if true, shows that the viscosity of any gas sliould be independent of its density at a constant temperature, and should in- crease proportionally to the value of u. But u'^ is proportional to the absolute temperature, whence we see that the viscosity should increase proportionally to the square root of the absolute temperature (which we may reckon from — 273*0.). Maxwell has also pointed out * that in this expression we should obtain the same result with regard to the pressure, whatever ast^umption we adopt of the mutual action at impact of the molecule ; but tiiat it is necessary to make some special assump- tion upon the nature of this action to determine the variation with the temperature.

Previous to this deduction by Maxwell, there had been but little work done upon the viscosity of gases, and almost nothing as to its variation with temperature. Subsequently, experiments have beeu made by Meyer, Maxwell, Puluj, and v(m Oliermayer. The forms of apparatus used have depended upon two fundamental methods : I*', the retardation of pendtdums by the surrounding ga-es ; 2°, the transpira- tion of gases through capillary tubes. In the present pai)er, I propose to discuss somewhat the value of these experiments in determining the variation of the viscosity with the temperature, and to describe some recent experiments made with a modification of the second of the above methods.

In a paper published in Poggendorff's Annalen, exxv., 177, 1865, O. E. Meyer describes a series of experiments upon the internal friction of air made by measuring the retardation of three circular glass plates oscillating around a vertical axis in a closed receiver containing the gas, whose temperature and pressure could be varied. From the results of these measurements, Meyer concludes that the coefficient of viscosity is independent of the pressure. It will, however, be evident, upon an inspection of the published results, — especially by application of the graphical method, — that no reliance can be placed ui)on them for de- termining variation with the tempeiature. IVIeyer's second paper (Pogg. Ann. cxxvii., 199, 353) is devoted to a discussion of Graham's transpiration experiments,t from which we may derive quite a satis- factory proof of the law of Poiseuille as a|)plied to gases. In the Philosophical Transactions, London, 186G, Maxwell published a series

* Pliil. Mag. XXXV., 211.

t riiil. Trans. Roy. Soc. Lond. 1846-49.

OF ARTS AND SCIENCES. 43

of results obtained by a similar apparatus to that used by Meyer. From these Maxwell concludes that the viscosity is independent of the pressure upon the gas, aud that it increases as the first power of the absolute temperature. If, however, the results published in that paper be all upon which this law is based, we cannot regard it as very securely established. A third pa{)er was published by Meyer, in Pogg. Ann. cxliii., 14 ; in which the results of seven experiments with oscil- lating plates after Maxwell's pattern, but with bitilar suspension, were given. These, like the others, are iusutiicient to determine the etFect of temperature. In three subsequent papers* by Meyer a large num- ber of experiments are described. These were made by the method of transpiration through capillary tubes, and preliminary experiments were made to prove the validity of the law of Poiseuille. This law may be expressed by the following equation : —

where V is the volume of gas transpired in the time t, measured at the temperature of the capillary, and under the pressure p ; the pressure at entering tlie tube being jo,, and at leaving it jo,. The length of the capillary is 1, and its radius R ; ij being the coefficient of viscosity of the gas. This law may, I think, be regarded as established for varia- tions of pressure not exceeding two atmospheres, and for tubes in which the length is very large as compared with the diameter.

]Meyer gives a series of twenty-five experiments, and selects eleven as the most reliable. These all seem to indicate an increase of viscos- ity with rising temperature greater than the \ power, but appear at the same time quite discordant among themselves. Upon the ac- companying figure, I have shown the extremes of these by a graphical representation. The method used to discuss them is one described in the Proceedings of the Academy for 1874, page 222. If we have a line of the general form represented by the equation yz=.jnx^, we may take logarithms of both sides and get the equation, log y=-n \ogx -\- log m, which has the form of the ecjuation to a straight line. Hence, if we have the coordinates of a series of points which we suppose may be connected by a curve of the exponeutitU form, we may determine this fact by plotting logarithms of these cooi'dinates, which should give us points along a straight line whose tangent is the exponent in the primary equation. Thus, if our equation to the variation of ri with the

* Pogg. Ann. cxlvui., 1, 203, 526.

44

PROCEEDINGS OF THE AMERICAN ACADEMY

absolute temperature r be of the supposed form i] = ct', vvliere c is a constant, we may take the value of log t] and log t fi-ora our experi- ments, and expect upon plotting them to get a straight line making an angle whose tangent is x. This method I have applied to the results of Meyer, and the extreme points are shown at the points marked D and £ in the accompanying cut.

Fig. 1.

3.^

4.40

.00

The single experiment at zero centigrade gives the point 0. All the other experiments furnish points scattered between Z) and E. The absolute values of the coefficient in these cases are : —

For the line CD, x :

T =	»? =
C 273°. (7	0.000168
D 203°.2	0.000198
E 287°.5	0.000178
- 2.3 ; for the line GE, a;— 1.12.	This gives us

OP ARTS AND SCIENCES. 45

an idea of the value of these results in determining the variation of the viscosity with the temperature. We cannot say from them, wliether this variation is proportional to the first or second power of the absolute temperature. Even the results published in the tifth paper, which was to determine this law, are insutHcient. In the first series of these re- sults, shown upon the curve by the extreme lines NS and TS, we see that the exponent representing the law of variation with the tempera- ture varies from x= 0.2 1 for line NS to x=.[).i)9 for line TS, a variation even greater than in the results previously discussed. All the other observations give points intermediate between xVund T, The second series furnishes little better data; and the tliird series, from determinations witii oscillating plates, are not sufficiently complete for discussion in tliis way. They, however, afford no greater satisfaction.

Puluj has used the method of transpiration for some measurements of this law, and his results appear in the Sitz'ber. Wien. Acad, of 1874, Ixix., 287. The results which he has obtained appear rather more concordant than those of Meyer, but still siiow considerable disagreement. Upon the above cut, the lines OP and 0 Q show the extremes of these results as obtained by a discussion of his experi- ments. These lines do not represent the greatest variations between successive results in the same series, but the extreme variation between the mean results of various series. For OP, x= O.Go ; for OQ, x = 0A7. It will thus be seen that these results are more concordant than the different series of Meyer : they are not, however, completely satisfactory.

Later than these we have a brief notice of some experiments by von Obermayer, in the Phil. Mag., xlix., 332, 1875, in which he states that he has ol)tained results " which confirm those of JNIeyer's experi- ments in a perfectly satisfactory manner." He states Meyer's results as furnishing the exponent | for the variation of q with the absolute temperature ; whence we must conclude that this number expresses the result at which he has arrived.

What value now are we to place upon these results, and which is the true one ? Maxwell has given a: = 1 ; Meyer, x =z ^ ; Puluj, a; = f ; von Obennnyer, x = |. The first two values, x =1 and a:=:|, we can hardly accept as certain, from the consilerations pre- viously shown. Tlie value given by Puluj of x=5 is undoubtedly somewhat greater than is warranted by his results. Of the remaining experiments we cannot judge, since they have not yet appeared in full, so far as I have been able to ascertain.

The importance of this question in its bearing upon the kinetic

46

PROCEEDINGS OP THE AMERICAN ACADEMY

theory, as well as from its prominent plaee among the phenomena of gases, renders it very desirable that we should know the true law.

In endeavoring to arrange some new form of apparatus for a more accurate study of this law, the idea of a differential arrangement was sugjrested to me by Professor Pickering. This has been the origin of the following method. Two glass capillaries, AB and CD, were placed side by side, each in a tin trough to contain a bath to regulate the temperature of the gas. Air-tight glass and rubber connectors extended from G to the gauge F, and to tlie end D of one capillary. The ends ^ and Cof the capillaries were connected with the gauge E by means of a T joint of glass. Tiie end A of the second tube communicated with the external air throusfh the chloride of calcium tubes -^aad I. The size of the connectors at the ends of AB

Fig:. 2.

and CD was sufficient to allow the gas to assume the temperature of the bath. The tube at G was connected with a large flask, from which the air was continuously exhausted by means of a Richards' jet aspira- tor. The size of this flask rendered the pressure co:istant in spite of slight variations in water pressure. An inspection of this arrangement will show that when the flask is exhausted, and a vacuum produced at G, the air will enter at A under the atmospheric pressure, and will pass with constantly diminishing pressure to G ; so that, at any inter- mediate point, as the junction of the two tubes at BC, we shall have a pressure intermediate between the two extremes. It will also be seea that the same volume of air is successively transpired through ^5 and CD; providing that there be no leak, which was carefully guarded against by making all the joints about C, B, and B — which were the only ones that affected the results — as tight as possible. By the two baths we may have the gas transpired successively through AB and

OF ARTS AND SCIENCES. 47

(7Z), either at the same or at different temperatures. Now, if we de- note by Fj, i?j, ^p r]^, &c., the vohime of gas transpired by A£, the radius and length of AB, and the coefficient of viscosity of the air pass- ing througii it, while V^, &c., represent the same quantities for CD ; also, if PpP2' 7'" Pi '"epresent the pressure of the gas at A, B, C, and B respectively as obtained from the gauge and bai'ometer readings ; then from (1) we may write,

and

But if both baths are at the same temperature F^ = F^ if <^ ^ #05 and 11^ = /^i,? whence we may write,

^V^i ~ Ih'-p-z''

(4.)

Also in general it will be seen from the nature of the apparatus that

V V.

1 — — — where 8^ and 8.^ represent respectively the tempera-

l-l-a5^ 1 -|- "So

tures at which \\ and F^ are transpired. Hence

(o.)

From equation (0) it will be seen that, in order to determine with this apparatus the ratio j/j : //„ between the coefficients of viscosity in the two tubes when the temperature of these is 8^ and 8.^ respectively, we have onl}- to know the ratio of the dimensions as expressed by

jHrti and to measure jt?p p.^, and p^ by reading three mercury columns.

Also we can obtain a value of Trrr f™m readings of the gauges when

8^ = 8.,, which needs only to be corrected for expansion of the glass to be used directly in equation (5). The whole process is thus re- duced to the simple matter of reading columns of mercury, no meas- ure-ments of volumes of gas being necessary. The nature of the correction of Ji and I for temperature appears by putting into the above formuhs in which these values are supposed to be for 0° C, the coefficients of expansion of the glass =: A ; we thus get from (5) : —

Vj _ R,H\ -}- A6,)%{1 -\- A6.2) Pi'-P^^ 1 + «S2 V2 — /?2'( 1 + A6,]iX,( 1 + .4c5j • ;v -7-3- ' I + aS,

(6.) _R,H\-\-AdJ^?., pf-pl 1 + oh

48 PROCEEDINGS OF THE AMERICAN ACADEMY

Lest, however, an error might occur in the last reduction fi'om a difference between the coefficient of expansion of the bore of a capillary tube and of its lineal expansion, I have carefidly measured both, and find that the coefficient for the bore is 0.0000075, while for the linear expansion I find 0.0i)00080 per degree centigrade, a difference too slight to affect the results in my use of it ; I have thought it best to use the value 0.0000075 as it entered in the fourth power, while the other entered only in the first power. The tubes used have also been calibrated to insure the selection of those of uniform bore, and their dimensions have been accurately measured by mercury and a micro- meter screw. The dimensions of the two tubes used in ihe experi- ments to be described, were, for tube No. I., }. = 1272.3 mm., R = 0.1098 mm. ; for tube No. II., ;i= 1274.1 mm., ie = 0.1115 mm.

To make an experiment with this apparatus, it is merely necessary to start the jet of wafei" and allow the exhaustion to proceed until the mercury columns in J^ and J^ have come completely to rest. Read- ings are then taken of the heiglits of these columns by means of a cathetometer from a steel scale placed beside the gauges. Tlie reading of the barometer corrected for instrumental error gives the pressure at A. All these are reduced to the freezing point, and A' and i^are corrected for capillaiity by the tables of Delcros. <rhe temperature of the baths is also taken by thermometers in various positions in the troughs. This must be kept constant throughout the experiment, and I have, therefore, principally used the temperatures of melting ice and boiling water. In the experiments of which the following table gives the results, advantage ha^s been taken of the four methods of checking the results of one experiment by another, by reversing tiie direction of flow of the air through the tubes and heating alternately? in each case, first one and then the other trough. In the table, column first gives the number of the experiment; column second, the direction of flow of the air, which entered at the tube whose number is first given and passed out from the other ; columns three, four and five give the pressures at A, B and D respective'ly ; columns six and seven show the temperatures in centigrade degrees of the baths around tubes I. and II. respectively ;

column eight shows the values of the ratio j^-^ at different tempera-

tures ; column nine, the values of — , i.e. of ri at the higher to ?/ at the

lower temperature ; column ten shows the values of the exponent x in tlie equation )^= cr^. This is the quantity which it was the object of the experiments to obtain.

OF ARTS AND SCIENCES.

49

No.	Dir.	Z*!	Pi	Pi	3-1.	^11.		V2	X
		m. m.	m. m.	VI. 711.
1	I.-II.	759.9	525 2	16 3	ii'o	17.°0	0.912
•1	»1	,,	5i9.3	17.1	17.0	47.5		1.083	0.799
4	}f	759.8	525 6	18 0	15.1	15.1	0.916
5	M	'1	584.4	18.9	1 »	J?	0.921
6	J»	765.7	550.9	18.6	17.8	178	0.934
7	II-I.	)f	490 7	17.7	17.5	99.0		1.212	0.776
8	>>	)»	491.2	17.6	17.5	99.5		1.206	0.755
9	»I	«»	490.0	17.3	17.5	99.8		1.215	0 780
11		755.2	467.8	20.4	0.0	100.0		1.272	0.771
12	»>	»>	46K.4	19.4	>)	>J		1 2()7	0.7,57
VA	)J	>1	467.9	19.6	))	>)		1.271	0.708
14	J»	I»	Vu 7	19.3	)*	)'		1.273	0.773
16		»t	&14.2	20 7	0.0	0.0	0.027
17	i.-i'i.	756.7	525.3	23.4	*»	VI	0.928
18	J)	T1	5W.8	21.5	0.0	100.0		1.277	0782
19	It	761.4	529 1	16.1	100.0	100.0	0.933
20	>>	762.0	530.2	16 7	f*	?»	0.937
21	M	763.1	452.2	18.5	100.0	0.0		1.259	0.738

Vi

R^%

In the calculation of the ratio - of this table, the value of ^ ^ used

was the mean of that obtained from experiments 16 and 17, after cor- recting for temperature. The agreement of these two values within 0.1 per cent is a test of the accuracy of the method, as the two ex- periments were made on different days, and the direction of the current was reversed. It will be seen that the vahie of this quantity increases slightly with the temperature, as we should expect from the slight ditFerence in size of the two tubes used. The values of x will be seen to agree quite closely, with the exception of experiments 2 and 21. I have treated these results in the same manner as those of Meyer, and the result is shown on Fiij. 1-

The point A is plotted from experiment 18. and i? from 21 ; so that the lines AC and BC show the greatest variation in nine out of ten determinations, while the majority of these lie so close together as not to be capable of clear representation between A and B. The point C has been raised from C for distinctness. Experiment 2 would indicate a deviation from the straight line ; but I do not regard this as a per- fectly reliable determination. More experiments are needed between 0° and 100° to establish the law.

In order to compare these results with those of Meyer, I have been obliged to assume his value of jy = 0.000168 at 0.° C. as a start- ing-point, since the apparatus which I have used does not give absolute values of the coefficient of viscosity, but only ratios. It would ap- pear, however, that the great concordance among the results thus far obtained would warrant its application to absolute measurements, for

VOL. XII. (n. S. IV.) 4

60 PROCEEDINGS OF THE AMERICAN ACADEMY

which it would only be necessary to measure the "volume of the gas transpired in a known time. These, with experiments upon other gases, and also upon the validity of Poiseuille's law, I hope to be able to ac- complish. The many points of superiority of this apparatus, and the excellence of these preliminary results, would seem to indicate more accurate determinations than others preceding them.

As a result of these experiments, it would appear that the viscosity of air increases proportionally to the 0.77 power, nearly, of the absolute tempei-ature between 0° and 100° C. Tiiis value corresponds quite closely to the | power, and we might infer tiiat this was tlie value of x towards which the experiments pointed ; but as I feel assured that further experiments will furnish still more concordant results, I should be unwilling to accept 0.75 until tiiese had been performed. The gen- eral agreement of my results with the numbers of iMeyer and von Obermayer would seem to point to the fact that the value of x cannot be as great as unity, and is probably about 0.75.

Plate 1,

J7y<if«o"

■"^

Siiciair * ist lis:.

yhil3.

Canbya Candida.

Plate II.

^M ciadai: 4 Sm.iiit. Jbli ,

Arctomecon Californicum.

OP ARTS AND SCIENCES. 51

V.

CONTRIBUTIONS TO THE BOTANY OF NORTH

AMERICA.

By Asa Gray.

Presented June 13, and October 11, 1876.

1. Characters of Canhya {n. gen.) and Arctomecon.

WITH TWO PLATES.

CANBYA, Parry, nov. gen. Papaveracearum.

Sepala 3, caduca. Petala 6, obovata, diu persistentia, deraum scari- osa, capsulam obvolventia. Stamina 6-9 : filaraenta antheris oblongo- linearibus breviora. Ovarium subglobosum : placentae 3, nerviformes, multiovulatfB : stylus nullus : stigmata 3, oblongo-linearia, reflexo- divaricata, ovario adpressa, placentis superposita, facie superiore (interiore) prorsus papillosa. Capsula ovoidea, membranacea, a vertice ad basim trivalvis, valvis placentas filiformes cum stigmatibus persistentes nudantibus. Semina plurima, elongato-oblonga, parum arcuata; testa laevissima nitida ; rhaphe baud prominula nuda. Embryo prope basim albuminis minimus, cylindraceus. — Herbula annua, glabra, parum unci- alis ; foliis alternis linearibus integerrimis subcarnosis cum ramis brevissimis ciBspitoso-confertissimis ; scapis perplurimis filiformibus (semipollicaribus) unifloris ; petalis l«te albis.

Canbya CANDIDA, Parry. South-eastern California, in sandy soil on the Upper Mohave River, Dr. E. Palmer, May 18, 1876 (in flower and fruit). — This charming little winter-annual is one of the discov- eries made by the botanical party, consisting of Doctors Palmer and Parry and Mr. Lemmon, which passed last winter in S. E. California and adjacent districts. Dr. Parry, who immediately recognized its botanical interest, proposed to dedicate the plant to our common friend and worthy fellow botanist, William ]\I. Canby, Esq., of Wilmington, Delaware ; and I have peculiar pleasure in carrying this proposition into effect.

52 PROCEEDINGS OF THE AMERICAN ACADEMY

The plant is of most diminutive size, but of much botanical interest and no small beauty. From the Sagina-Wkc tuft of foliage at the surface of the ground rises a multitude of tiny peduncles or scapes, each tipped with a bright white flower which lasts for many days ; the petals (barely two lines long) opening at sunrise, and at sunset closing over the ovary, and at length permanently over the capsule, into a globular form, which the discoverer likens to a pearl. The most unexpected anomaly in this order of a persistent (instead of ca- ducous) corolla is shared by Arctomecon, native of the same district, as Dr. Parry himself ascertained upon rediscovering that exceedingly rare plant in the spring of the preceding year. There are other Papaveraceous plants which hold their petals for a day or two, notably Sanguinaria in which they open and close for four or five days before falling; but in these two peculiar genera they become scarious, re- maining permanently in Arctoniecon, and up to the full maturity of the capsule iu Canhya.

The two genera, although closely related, differ in some important points of floral structure as well as in aspect. The most marked differ- ence is in the stigmas, which in Canhya are perfectly sessile, long, entire, and divergent to the utmost, so that their backs are closely applied to the surface of the rounded top of the ovary, directly over the placentae, and the upper or ventral face papillose-stigmatic ; while Arctomecon has a short style, the indistinct lobes of which bear extrorse and two-lobed stigmas, which are alternate with the placentae, and are closely appressed or even partly united in a kind of head. The capsule of the one is membranaceous and dehiscent to the base; of the other, coriaceous and apparently dehiscent only to the middle. The seeds and the stamens are likewise different. The wretched figure of Arctomecon in Fremont's Report exhibits none of these characters, and it led Bentham and Hooker to conjecture that plant might be only a Papaver, allied to P. nudicaule. Dr. Parry's specimens were received in time for a partial, reconsti-uction of the generic character in the Botany of California ; but the position of the stigmas and the presence of a j^rominent crest of the seed have not before been noticed. A full character of that genus is therefore here given, along with that of Canhya.

ARCTOMECON, Torr.

Sepala 2, raro 3 ? Petala 4, latissime obovata, persistentia, demum tenuiter scariosa. Stamina indefinite plurima: filamenta sursum parum dilatata, antheris brevi-linearibus lougiora. Ovarium obovoideum:

OF ARTS AND SCIENCES. 53

placentaj 3-6, nerviformes, pluriovulatae : stylus brevissimus, sublobatus, lobis erectis pi. m. coadunatis stigmata placentis alterna cordato-biloba capitato-couferta extrorsum gereiitibus. Capsula obovoidea, suban- giilata, apice brevitcr 3-6-valvis; valvis coriaceis a placentis filiforra- ibus stylo brevissimo persistente connexis solutis. Semina paiiciuscula, majuscula, oblonga, recta; rhaplie cristata; testa tenuiter lineolata, crista ad hilurn cariincnlato-dilatata sursum sensim angustiore. Em- bryo cylindraceus, alhumine § brevior. — Ilerba nana, ut videtur biennis; foliis alternis (summisve nunc oppositis) cuneatis vel spathu- lato-lanceolatis apice 2-o-dentatis seu inciso lobatis barbato-setosis ; pedunculis subumbellatis nunc scapiformibus uniiioi'is ; floribus majus- culis albis.

Akctomecon Californiccm, Torr. in Frem. Rep. ed. 2, 312, t. 2; Parry in Am. JSaturalist, ix. 139 & 268 ; Brewer «& Watson, Bot. Calif, i. 21.

The accompanying plates illustrate the two genera: —

PLATE I. CANBYA CANDIDA. Plant of the natural size. Fig. 1. Flower bud, enlarged.

2. Expanded flower, enlarged.

3. Stamen, more magnified, as are all the following details.

4. Base of ovary showing cross section, and upper part, with the stigmas. 6. Mature capsule witli the investing persistent petals.

6. Dehiscent capsule, with seeds.

7. Same, the seeds fallen.

8. Seed, more magnified.

9. Embryo, on the same scale.

PLATE II. AKCTOMECON CALIFORNICUM. Natural size : the detaus variously magnified. Fig. 1. A stamen.

2. Pistil transversely divided.

3. Dehiscent capsule.

4. Seed, lateral view.

5. Same, witli crest anterior.

6. Embryo, equally magnified with the seed.

7. Portion of surface of seed, more magnified, to show the lineolation.

8. Portion of bristle from a leaf.

64 PROCEEDINGS OF THE AMERICAN ACADEMY

2. Characters of New Species, &c.

IsorYRUM STiPiTATUM. Perenne ; radicibus fuscicnlatis ; caulibiis spitham^is versus apicetn 1-2-foliatis 1-2-rioris; foliis radicalibus tri- caulinis saepius bi-ternatisectis, petioliilis primariis secundariisque elonofatis, sesmentis ultimis foliolisve sessilil)us nunc confluentibus lineari-oblongis intefrris vel cuneatis trifidis ; pedunculo sub flore parvo incrassato ; sepalis 4-5 oblongis ; petalis niillis ; staminibus parum 10, filainentis subulato-complanatis : folliculis totidem oblongis utrinque obtusissimis vix venosis 3-4-spermis longiuscule stipitatis. — Northern C^dif()rnia, near Yreka, Siskiyou Co., April, 187G, under Ceanothiis and Oak bushes, Rev. E. L. Greene. A most distinct species ; with flowers much smaller tlian those of T. occidentale, of which it has the habit, although larger than those of T. fumarioides. Stipe of the fruit nearly a Line long.

Nastuktium traciiycarpum. E radice annua ? erectum, ramosum (pedale), fere glabrum ; foliis lyrato-subpinnaiitidis ; racemis laxis ; floribus albidis ; petalis spathnlatis sepala antherasque oblongo-sagitta- tas parum supeiantibus ; siliquis oblongo-linearibus (lin. 4-5 longis) papilloso-asperatis in pedicello rigido mox recnrvato curvato-adscenden- tibus stylo longo subulato superatis. — S. W. Colorado, on the San Juan, &c., T. S. Brandegee, in Hay den's Expedition, 1875. The rhachis of the raceme and the stout peilicels are more or less studded with the small rough papill;^ which abound on the pod and suggest the name for the specirs, which is a very distinct one.

Lepidium dictyotdm, Gray, var. ? acutidens, siliculis magis ovatis, dentibus loniiioribus deltoideo- immo subulato-trian<fulatis omnino acu- tis. — California at Yreka, E. L. Greene.

Claytonia bulbifkka. C. SibiriccB, L. (alsinodei, Sims) similis, sedbulbillis radicalibus bulboso-confertis pereunans; ra'-emis elongandis fulioso-bracteatis ; bracteis spathnlatis sen lineari-oblongis ; sepalis latioribus, fructiferis dilatatis. — Scott Mountains, Siskiyou Co., Cali- fornia, P>. L. Greene. Also received from some other Californian col- lectors, but without the bulbiferous base. To the acute observation of Mr. Greene we are also indebted for an indication of the characters which appear to demand the re-establishment of C. parvijlora, Hook, and perhaps one or two other specicvS.

Astragalus coi>linus. Dough, var. C\lifornicus, leguminibus cum stipite sesquipoUicaribus purpureo-marmoratis. — Yreka, Califor- nia, E. L. Greene.

Astragalus FLAVus, Nutt, var. candicans. Canescens ; pedun-

OF ARTS AND SCIENCES. 55

culis subscapiformibus. — Near Richfield, Utah, at 5,900 feet, in loose a§hy soil, Lester F. Ward, in Powell's Expedition. Apparently a form of Nattall's species, but more condensed as well as hoary, and witli somewhat the aspect of Oxytropis. The specimens supply mature fruit, which is wanting in Nuttall's specimens. The legume is one-celled, with little or uo introflexion or thickening of the dorsal suture ; while externally the ventral suture has a very salient ridge and a shallow and broad groove each side of it, somewhat in the manner of A. bisulcafus.

Astragalus Ward[. laflnti : perennis? viridis, undiqne fere gla- ber ; caulibus erectis nltrapedalibiis foliosis : stipulis triangularibus vel subnlatis parviilis : foliolis multijngis angusto-oblongis obtusis retusisve (lin. 3-4 longis) ; pedunculis filiformibus folio brevioribus laxe racemoso- 10-15-floris; floribus moxpendulis; calycis dentibus subulato-setaceis tubo breviter campanulato aeqiiilongis ; corolla alba nunc purpurascente lin. 2-3 longa; legumine vesiculoso ovato acuto recto sub«quilatero baud stipitato glaberrimo purpureo-marniorato |-pollicari. — Sevier Co., Utah, on the edge of Aquarin's Plateau, at 8,700 feet, Lester F. Ward, in Powell's Expedition.

Astragalus Newberkyt. Scyfocarpi : subcaulescens ; caudicibus in radice elongato profundo brevissimis confertis ; foliis argenteo-seri- ceis ; foliolis 3-7 nunc lato- nunc angusto-obovatis approximatis (lin. 4—6 longis) ; pedunculis brevibus vel brevissimis pauciHoris ; calyce cylindraceo sericeo, dentibus tubo plus dimidio brevioribus ; corolla ochroleuca |-pollicari, unguibus elongatis ; legumine chartaceo ovato infiato villoso pollicari uiiiloculari, acumine lato lateraliter compresso subincurvo, suturis baud incrassatis nee intiis nee extus prominulis. — A. Chamceleuce, Gray in Bot. Iv'es Colorad. Exp. 10, quoad pi. New- berry.— On the frontiers of Utah and Arizona, Prof. Newberry. Cafion east nf Glen wood, Sevier Co., Utah, at 7,000 feet, Lester F. Ward, in Powell's Expedition, 1875. Having now the fruit, it is clear that Newberry's plant, in flower only, is not the same as Phaca pyg- mcea, Nutt., which should retain the name of A. Chamceleuce, while this may take that of the original discoverer.

Astragalus Patthrsoxf. Snjfocarpi : robustus, 1-2-pedalis, ad- presso-piiberulus, nunc glabellus ; foliolis 6-10-jugis oblongis crassius- cnlis (semipoll. ad pollicem longis) : pedimculis racemoso-plurifloris folium fcquantibus vel superantibus ; floribus mox pendulis ultra-semi- pollicaribiis ; calycis dentibus setaceo-subulatis tubo cylindraceo dimidio brevioribus ; corolla alba ; carina apice nunc purpurascente ; legumine ovali crasso-coriaceo inflate glabro (saepius pollicari) polyspermo, basi intra calycem abrupte contracta substipitiformi, suturis nee intrusis nee

56 PROCEEDINGS OP THE AMERICAN ACADEMY

extus prominulis. — Foot-hills of Gore Mountains, Colorado, H. N. Patterson. Rio McElmo, Southwestern Colorado, T. S. Brandegee, in Haydeii's Expedition, 1875. Utah on Dirty-Devil River, and near Richfield, L. F. Ward, in Powell's Expedition, 1875. The two last in fruit only ; while the fruit of Mr. Patterson's plant (who alone has found the flowers) is decidedly smaller, sometimes little over half an inch lonw.

Astragalus subcompressus. A. racemoso sect. Galegiformhim admodum siniilis ; dentibus calycis brevioribus ; corolla ochroleuca ; legumine falcato lateraliter compresso intus septo completo bilocellato, sulco dorsali angusto subclauso, stipite e calycis tubo baud exserto. — S. W. Colorado, common at the altitude of 7,000 feet, T. S. Brandegee, in Haydeu's Exped. 1875. Legumes an inch and a quarter or only an inch long, 2\ to nearly 3 lines wide, the well-developed ones decidedly falcate ; the partition about twice the length of the depth of the groove, which in the cross-section of the well-grown pod before dehiscence is oval and almost closed.

Astragalus ITaydknianus. A. bisulcato affinis, minor; pube magis cinerea ; spica elongata virgata ; floribus multo minoribus (lin. 3-4 longis) ; calycis dentibus subulatis tubo multo brevioribus ; corolla alba, carina apice purpureo tincta ; legumine ovali utrinque obtusissimo venis transversis ruguloso 6-7-ovulato 2-4-spermo, facie ventrali late profundeque impressa sutura ccstteformi valde piominente percursa, stipite calycem hand superante. — Common in S. W. Colorado, at the altitude of 7,000 feet, T. S. Brandegee, in Hayden's Expedition, 1875. Also banks of Grand River in Middle Park, II. N. Patterson. " Plant 2 or 3 feet high." Dedicated to Dr. F. V. Hayden, the Director of the expedition in wliich it was collected, and the distinguished ex- plorer and surveyor of our whole Rocky Mountain district.

Astragalus tricarinatus. A. arrccto subsimilis, 1-2-pedalis ; foliolis plnrimis parvis (lin. 3-4 longis) ovalibus obovatisve emarjiinatis crassiusculis supra glabellis subtus cauo-puberulis secus rhachin elon- gatam sat rigidam sparsis vel remotiusculis ; racemis sparsifloris longe pedunculati:^ ; bracteis ovato-subulatis minimis ; floribus subpatentibus ; calycis nigro-hirsutuli tubo brevi-campanulato pe^licello aequilongo dentibus subulatis parura longiore ; corolla ochroleuca sen flavida (semi- pollicem longa) ; ovario glaberrimo ; legumine lato-lineari, matnro arcuato ultrapollicari coriaceo bilocellato quasi tiicarinato, nempe dorso inter carinas obtusas late sulcato, ventre acutissime carinato, faciebus concavis, sectione transversa late Y-formi, stipite calycis tubo breviore. — White Water, San Bernardino Co., California, Parry, 1876.

OP ARTS AND SCIENCES. 57

Astragalus humtllimus. Caespitoso-depressus, condensatus ; caudice lignescente ; caulibus vix polli<;anbus stipulis scariosis coalitis imbricato-tectis petiolis persistentibus hystricosis ; foliolis 3-5-jugis oblongis canescentibus mai'jjine revolutis liiieain lon^is demiini de- cidiiis ; pedum-ulis brevibus 1-3-flons ; calycis deiitibus subulads tubo oblongo-campanulato dimidio brevioribus; corolla pallida: k^guraine ovato coriaceo albido-pubescente parvo (liii. 2 loiigo) uniloculari 9-ovulato fere moiiosperuio, siituris extus promiuulis. — Flat rocky grounds on the jMesa Verde, S. W. Colorado, T. S. Brandcgee, in Hayden's Expedition, 1875. Habit of A.jejimns, AVatson, but much more dwarf and condensed, not rising moie than 2 or 3 inches above the ground, and often choked in drifting sand. Persistent petioles and rhachis only an inch long, more rigid and spinescent than those of A. Jejunus, which are also persistent : the jjod decidedly different.

Lespedeza leptostachya, Engelm. in herb. Gray. Pube undique adpressa argenteo-canescens ; petiolo j)etiolulo terminali longiore ; foliolis linearibus ; spicis paniculatis gracilibus sublaxifloris longiuscule pedunculatis ; legumine calycem adsequante vel subsuperante. — Min- nesota, T.J. Hale. Illinois, Bebb. Iowa, T. C. Arthur, Bessey. Has passed for L. angusti folia, from which its slender s()ikes and paniculate habit at once distinguish it. Our species of the group are dilficult and need revision, witii very ample materials to be studied with the atten- tion which Maxiraowicz has bestowed upon the Asiatic species. L. capitafa, Michx., should be known by its very short petioles, short- peduncled and globular heads of flowers, and legume much shorter than the calyx ; L. angusfifolia. Ell., by smaller and often oblong heads, on distinct ami sometimes slender peduncles, and legumes hardly shorter than the calyx, the leaflets linear ; L. kirta, by pubescence of stem perhaps always spreading, leaflets from orbicular to narrow oblong, petioles mostly slender, oblong spikes on elongated peduncles, and legume at maturity hardly shorter than the cnlyx.

Epilobium jucundum. E. paniculato affine ; floribus multo majori- bus thyrsoideo-paniculatis ; calycis tubo ultra ovarium longe producto tubuloso-infundibuliformi ; petalis Isete purpureis late obcordatis semi- pollicaribus ; antheris fere linearibus ; stylo prrelongo. — Scott Valley, Siskij'ou Co., California, E. L. Greene, Aug. 28, 1876. A showy species, well worthy of cultivation, having llowers almost as large as those of E. obcordaium, and very numerous in a rather crowded pani- cle. The calyx beyond the ovary is half an inch long, more narrowly funuel-form thau in E. paniculatum, the tubular part about equalling

58 PROCEEDINGS OF THE AMERICAN ACADEMY

the ovary ; the petals are much broader as well as larger, and the anthers (of short-linear outline) fully twice longer.

Galium Brandegei. Caespitoso-depressum, parvum, glabrum, laevissimum ; radieibus fibrosis ; foliis quaternis obovatis vel spathulatis fere aveniis lin. 1-3 longis; peduncuHs uniHoris solitariis biiiisve nudis ; flore albido semi-lineam loiigo ; fructu l,T3vi glabro. — Valley of the Rio Grande, New Mexico, on Los Finos Trail, at 9,000 feet, Sept,,- 1875, T. S. Brandegee, in Hayden's Expedition. Spreading extensively over the barely moist ground, evidently perennial ; the stems only 2 or 3 inches long. We have no other North American s^Decies much resembling this.

BiiicivELLiA Greenei. Subsesquipedalis, pube viscidissima ; cauli- bus usque ad capitula solitaria ramus terminantia foliosis ; foliis cauli- nis ovatis obtusis medium versus inajqualiter serratis basi subtruncatis brevissirne petiolatis, ramealibus oblongis subintegerrimis, sumrais capitulum involucrantibus eoque brevioribus ; involucro proprio multi- floro, squamis liuearibus acumiaatis glabellis, extiniis brevioribus tan- tum lauceolatis ; acheniis ad angulos hirtellis. — Siskiyou Co., California, on the south fork of Scott River, E. L. Greene, Aug. '24, 1876. Cau- line leaves an inch long, thinnish ; those of the short and somewhat corymbose flowering branches barely half an inch long. Head three quarters of an inch long.

BiGELOViA Vaseyi. Chrysothamnus : depressa, glabra, Ifevis ; cau- libus e basi decumbente erectis spithamaeis ; foliis atigustis spathulato- linearibus obtusis: capitulis corymboso-confertis plerumque sessilibus ; involucro aiigusto oblongo subclavato 5-floro, squamis minus carinatis oblongis obtusissimis chartaceis, exterioribus apice crassiore viridulo ; appendicibus styli obtusiusculis parte stiginatica lineari dimidio brevioribus ; ovario glaberrimo. — Colorado, in Middle Park, Dr. Geo. Yasey. in Powell's Exped., 1868. Utah, on Aquarin's Plateau, at 9,000 feet, L. F. Ward, in Powell's Exped., 1875. Leaves an inch or less in length, a line or less wide. Heads in Vasey's specimens 4 lines long, in Ward's better developed ones are 5 or almost 6 lines long; the scales of the involucre less carinate and less prominently straight ranked than in the related species ; the greenish tij)s also suggesting the Aplodiscus section.

SoLiDAGO SPARSIFLORA. Virgaurea, Virgatce : scabrido-puberula ; foliis inferioribus ignotis, su; erioribus floralibusque parvulis lanceolatis (lin. 6-12 longis); racemulis oligocephalis laxis laxcque thyrsoideis ; involucri squamis linearibus ])uberulis apice viridulis acutiusculis ; flori- bus radii circiter 10 ligulis parvulis, disci 4-5 ; acheniis sericeo-pubes-

OF AllTS AND SCIENCES. 59

centibus. — Arizona, near Camp Lowell, Sept., 1874. Rothrock, in Wlieekr Expedition, 1874.

Gymnolomia (Heliomeris) Porteri. Annua, ramosa ; foliislan- ceolatis linearibusque plerisque alternis integerrimis margine inferue parce hisjjidis ; capitulLs cymoso-pauiculatis, pedunculo gracili ; involu- cro laxo e squamis angiiste liiiearibus siibfoliaceis fere uniseriatis ligulas subjequantibus ; receptaculo alte conico; corolla disci fauce lati^sime campanulata lobis aequilonga, tubo abrupto brevi basi incras- sato ; St) lo basi bulboso, ramis liispidulis appeiidice tenuiter subulata hispida terminatis ; acbeniis turgidis hispidulis calvis, marginibus ad apicem latum truncatum in umlionem parvum productis, areola parva vix anuulata. — Hudbeckin? Porteri, Gray, PI. Fendl. 83. Stone Mountain, Upper Georgia, Porter, Hendee, Ravenel, and later Engel- mann and Canby, August and September.

Palafoxia Feayi. Scabra ; foliis oblongis lanceolatisque basi vel utrinque obtusis (poJlicaribiis) ; capitulis subcymosis ; involucro e squamis linearibus obtusis floribus 2-3-pIo brevioribus pedunculisque eglandulosis ; corollje fauce cylindracea lobisque breviusculis P. lineari- fijlicB ; pappi paleis oblongis obtusis basi incrassatis achetiio multoties corollae tubo dimidio brevioribus. — S. Florida, Dr. William T. Feay, Dr. Chapman.

HuLSEA Parryi. Hurailis ; foliis plerisque radicalibus confertis spathulatis infequaliter argute dentatis priuiura albo-lanuginosis ; cauli- bus floriferis plurimis scapiformibus (spithanijeis) gracilibus glabellis simplicibus monoce[)halis vel basi tlivisis bracteis paucis linearibus subulatisve instructis ; capitulo pro genere parvo (semipollicem alto) ; involucro viscoso-pubescente, squamis lato-linearibus flores disci ligu- lasque paucas incons[)icuas subfequantibus ; pappi paleis oblongis parum erosis subfequalibus. — S. E. California, in tiie Mohave district. Dr. Parry, 1876. The flowers appear to be yellow, with tips disposed to turn to purple.

Gaillardia spathulata. C. acaw/i spec, insigni peraffinis ; cau- libus spithamjBis e caudice perenni multicipiti plurimis plerumque ramosis foliatis ; foliis spalhulatis integerrimis basi sensim attenuata sessilibus ; pedunculo breviusculo , paj^pi paleis 9-11 oldongis longius aristatis, arista corollam disci mox superante. — S. Utah, in Rabbit Valley, at 7,000 feet, L. F. Ward, in Powell's p]xped., 1875. Leaves, as in G. acaidis, thickish and firm; the larger a full inch long; the uppermost reduced to half or a third of an inch. Heads rather smaller than in G. acauiis. on a slender terminal peduncle of an inch or two ia length. Disk-corollas 3 lines long.

60 PROCEEDINGS OP THE AMERICAN ACADEMY

Tetrabyimia comosa. Lagothamnus : lana gnaphaloiclea flealbata, 3— 4-peclalis ; ramis ramulisque erectis ; foliis sparsis linearibus plaiiis (s£Epe ultra-pollicaribiu-i) cuspidato-mucronatis aiitdeciduis autnoiiiiuUis in spinam modice induratam persistentem mutatis ; fat-cic'ulis axillaiibus nullis ; capitulis ad apicem ramosum corymboso-cymiilosis ; caeterum fere T. spinosce. — W. Nevada, Lemmoii. 8. E. borders of California, E. Palmer. Potrero, San Diego Co., D. Cleveland.

Nemacladds longiplouus. Foliis radicalibus magis cano-birtis; corolla tubulosa sepalis aequalibus a basi fere discretis sublinearibus 3-4- plo longioribus, tubo fere integro ; filamentis longius monadelphis ; ovario fusiformi ; capsula oblonga septo contrario subcompressa calyce libero plus diiplo longiure ; seminibus turgide ovalibus. — S. E. Cali- fornia, Wallace, Lemnion. A specimen of this, collected by Mr. Wal- lace (probably between Los Angeles and San Bernardino), has long been in our herbarium, but the charaoters have been noticed only nov? upon the coming of fine specimens collected recently by Mr. Lemmon. The flowers and fruit differ strikingly from those of iV^ ramosissimus, and call for emendation of tlie generic character. In the new species the calyx is actually free from the ovary and capsule, and 5-parted to the base, and the long and narrow capsule is 2-valved from top to bot- tom. It is very interesting to have a second species of this remarkable genus; but it throws no additional light upon its affinities.

Lobelia Ludoviciana. Inter L. paludusam et L. appendlculafam quasi media, glabra, caule 2-3-pe(lali gracili folioso ; foliis crassiusculis basi angustatis, superioribus lanceolatis acutis, inferioribus petiolatis, imis spathulatis obtusis ; racemo nudo laxe 5-2()-floro ; floribus secun- dis horizontalibus puberulis ; corolla casruleu semipollicari ; calycis tubo fere hemispboerico, lobis ovato- seu .(auriculis brevibus integris reflexis) cordato-lanceolatis tubo corolla; dimidio brevioribus capsula parum longioribus margine saepius integerriniis ; autheris majoribus superne hirsutis, apice imberbi. — In wet prairies, Western Louisiana, J. Hale ; Texas, near Houston. Liiidheimer.

Lobelia. Feayana. L. Cliffortiance et L. Berlandleri affinis, glabra, annna; caulibus spitbamajis ramosis ditfusis tenellis ; foliis (^-|-pollicaribus) obovatis vel rotundatis petiolatis repando-denticu- latis, summisve spathulatis seu lanceolatis sessilibus ; racerais nudis pedunculatis laxe 4-10-floris ; pedicellis (lin. 2—4 lougis) flori a;quiIongis bractea subulata 2— 3-plo longioribus ; calycis tubo capsulaque (§ iiifera) lato-obconicis, sinubus nudis, lobis subulatis tubo corollre laste ca^ruleae (parum lin. 2 longne) dimidio brevioribus apicem liberum capsuhv vix Buperautibus ; antheris glabris, brevioribus apice barbulatis ; seminibus

OF ARTS AND SCIENCES. 61

oblongis, te*ta cellulosa. — Eastern and Southern Florida, Dr. Feay, Dr. K. Palmer, Mrs. Treat, &c.

Akctostaphylos Clevelandi. a. bicoloris quoad folia et tomen- tum sat similis, bipedalis ; ramis longe crebreque foliosis ; foliis sub- sessilibus oblongis sublauceolatis cuspidato-acuminatis supra mox g^abratis iiitidulis subtus albido-tomentulosis ; racemis folioso-bractea- tis ; pedicellis bractea brevioribus flore diiplo longioribus supra niediuui folioso-bibracteolatis ; sepalis ovatis imbricatis tonientosis ; corolla brevi-oblonga sub-urceolata (lin. 4 loiiga) albida multinervulosa; fila- mentis subulatis villosis ; stigmate capitato ; disco hypogyno ovarii glabri dimidiiim aBquante : drupa ignota. — Potrero, San Diego Co., California, D. Cleveland, 1876. In flower Sept. 20.

Rhododendron Chapmanii. R. punctato perquam similis ; ramis rigidioribus erectis; foliis crassioribus minus petiolatis ; floribus prieco- cioribus ; corolla? infundibuliformis lobis ovatis tubo staminibus styloque brevioribus ; seminibus anguste oblongis. — R, pimctatum var. Cbapra. Fl. 266. — Sandy pine barrens of W. Florida, Dr. Chapman.

CLETHRA, PYROLA, etc. The early view that the anthers of Pyrolece. are in normal position in tiie bud (in other words, that they are extrorse and the foramina basal), to which I reverted in the later editions of the Manual of Bot. N. U. States, upon some observations by the late Prof. H. J. Clark, must be adhered to. Baillon, indeed (in Adansonia, i. 194), states the contrary with much particularity, appar- ently from direct ol)6ervation : " Cliaque loge se termine en un tube k pore de dehiscence apical. L'antliere est introrse quand le pore est en haut.; elle est, par consequent, extrorse quand le pore regarde en bas. Le filet est dans son jeune Tige rectiligne et dresse. Plus tard il s'alonge beaucoup et s'inflecliit en se moulant sur la convexite de I'anthere. Lors de I'epanouissement complet, il se redresse une seconde fois en totalite." I can affirm, on the contrary, that the anthers are developed from the first in this extrorse position, and undergo no in- version in the bud ; indeed, the anther is well formed and the basal horns i)lainly recognizable before the filament has an appreciable length, at least such as would allow the former to execute the supposed " mouvement de bascule."

Clethra agrees with the Pyrolece in having primarily extrorse anthers, as well as in the simple pollen and completely polypetalous corolla. These characters are fully equal in value to those upon which De Candolle and others break up the original Ericaceoi into separate orders, and, if apprehended by Bentham and Hooker, might have led them to give ordinal rank to the /*?/rofe«, appending Clethra, which they

62 PROCEEDINGS OP THE AMERICAN ACADEMY

almost exclude from Ericacece. Much preferring to retain the order as a jireat whole, I would combine Clethra and the tribe Fyrulece into the third suborder, Pyrolinece.

Galax aphylla, Linn. The name first appears in the first edition of the Species Flantarum, p. 200, in 1753. Neither generic nor spe- cific name has any fitness ; the herb is not milky, nor is it leafiess, except as to tiie scape. The plant in view, the Anonymos s. Belvedere, of Clayton, is recognizable by the good generic character in the first edition of the Flora Virginica, and from Clayton's herbarium. The generic character of Galax first appears a year later, in the 5th edition of the Genera Plantarum, and it is, as has been noted, utterly incongruous with Clayton's plant, to whicli Linnasus meant to apply it. This generic character Linnasus copied from Mitchell's Nova Planta- rum Genera, viz., from his VUicella, merely substituting the name of Galax. Consequently not a word of the Linn;«an generic character is applicable to Galax aphylla^ Linnanis's only species ; wherefore it is not surprising that Andrews, Richaid, and Ventenat should have re- spectively described that plant under other generic names. Although the contradiction was long ago pointed out, still most authors, down to Endlicher, De Candolle, and later, have followed LinuiBus in citing Viticella as a synonym of Galax. Gronovius, in the second edition of the Flora Virginica, was evidently struck by this total discrepancy ; and he covered it in a curious way, by omitting altogether the correct character of Clayton's plant, as printed in the original edition. It was reserved for INIr. Bentham to divine what Mitchell's Viticella really is, viz., HydropJtyllum appe^vliculatum, to which the name of Galax etymo- logically is equally inap|)lical)le. See lk'ntli.& Ilook. Gen. ii. 827.

STEIRONEMA, Raf. in Ann. Gen Phys. Brux. vii. 192 (1820). Genus between Trientalis and Lysiinacliia, distinguished from both by the presence of staminodia (the rudiments of the other series of stamens) between the fertile filaments, and by the {estivation of the corolla, in whicli each division is separately involute around, or even convolutely enwraps the stamen before it. The latter character, which I have I'ecently ascert dned, is not alluded to by Baudo in his index of the caulescent Anagallidece (Ann. Sci. Nat. ser. 2, xx.), nor by Bentham and Hooker in the second volume of the Genera Plantarum, in which tlie aestivation of the corolla is first systematically einployed in the arrangement of this order.* Following Bigelow (§ Seleucia) I had

* The tribe Li/simackiem is characterized as having convolute (or " contorted ") aestivation of the corolla; the Primulece, by quincuncially imbricated. This

OF ARTS AND SCIENCES. 63

long ago marked out Steironema as a subgenus ; but this new particu- lar warrants the complete se{)aration.

The species are not easy to define, as they incline to run into each other. But they are on the whole tolerably well distinguished in the later editions of the Manual of the Botany of the N. United States. iliey ace : —

S. ciLiATUM. (S. ciliata, Raf. 1. c.)

S. RADiCANS. Lysimachia radicans, Hook. Companion to Bot. Mag. i. 177.

S. LANCEOLATUM. {S. heleropliylla, Raf. & S. Jlorida, Baudo, mainly.) Lysimachia Ifinceolata, Walt. Var. hybrid um, tlie L. hy- brida, Michx. Var. angustifolium, the L. angustifuUa, Lam., and L. heterupliylla, Michx.

S. LONGIFOLIOM. (^S. longifuUa'^ & S. revoluta, Raf.) The oldest specific name is Lysimachia quadrijlora, Sims, Bot. Mag. t. G60, but that name is an inappropriate and deceptive one. L. longifoUa^ Pursh, is only a little later, and is unobjectionable.

FuAXiNUS Gkeggii. Onuis: fruticosa, glabra ; ramis gracilibus teretibus ; foliolis 3-7 angusto-spathulatis seu oblongo-obovatis obtusis obtuse paucidentatis vel integerrimis planis coriapeis fere aveniis sessili- bus parvis, petiolo inter foliola alato-marginato ; samara oblongo-lineari apice retusa stylo brevissimo apiculata. — F. Schiedeana vav. parviJoHa, Torr. Bot. Mex. Bound. 16G. — S. W. Texas, and adjacent parts of Mexico, Gregg, Schott, Bigelow, Parry.

FoRESTiERA Neo-Mexicana. F. acuminatcB proxima; foliis rai- noribus (pollicaribus) spathulato-oblongis apice obtusis vel obtuse subacuminatis brevi-petiolatis ; floribus foemineis fasciculatis (baud paniculatis) ; calyce minuto subpersistente ; drupis brevi-oblongis vel ovoideis obtusis. — F. acuminala var. parvifolia, Gray, Proc. Am. Acad. iv. 364:. — New Mexico, Fendler, C. Wright, Palmer, Brandegee.

holds well, the anomalous case of Steironema excepted, yet with somewhat of the gradations which are almost everywiiere apt to occur between these two modes. On tiie one iiand some PrimuJie (notably P. Boveana) will occasionally have three of the lobes in the "contorted" fashion, and only two wholly cov- ered ; on the other, species of Li/simachlu, such as L. clethroides, not rarely present flowers with one lobe wholly exterior and one wholly interior. By suppressing the tribe Li/siinachiece, C/jclauien and Dodecalheon are brought into juxtaposition, and the four tribes are made to rest on stable cliaracters, — Hot- toniece on the anatropous ovules, Corklece on tlie irregular flowers, and SamoletB on the adnation of the base of calyx and ovary.

The authors of the Genera Plantarum have overlooked the heterogone dimorphism of the flowers of Hottonia.

64 PROCEEDINGS OP THE AMERICAN ACADEMY

Amsonia brevifolia. Glabra ; foliis ovatis vel superiorlbus lan- ceolatis crassiusculis basi aiigustata subsessilibus ; corolla lobis ovatis oblongisve tubo subclavato dhnidio brevioribus, fauce sub ore tantum barbato : stigmate subtrochleari apice bilobato ; foUiculis moniliformi- torosis in articulis turgidis facile secedentibus. — S. Utab and "W. Arizona, to tlie border of California, Mrs. Tbouipson, Dr. Parry, Dr. Palmer. Tbere are four western species, forming a section, charac- terized by having a bilobed tip to the stigma, and the more or less clavate tube to tlie corolla always longer than the lobes ; the calyx deeply parted into attenuate-subulate divisions (2 or 3 lines long) ; the stems lower, more branched, and bearing smaller or simpler flower-clusters than the eastern species. Of these the present and the nearly i-elated A. tomentosa, Torr., have very torose follicles, disposed when dry to break up into joints. A. longijlora, Torr., and the following appear always to produce slender and continuous follicles, and have a tube to the corolla four or five times the length of the lobes.

Amsoxia Palmeri. Glabra ; foliis angusto-lanceolatis lineari- busque sessilibus ; corollce alboe lobis ovatis (lin. 1^-2 longis) tubo clavato intus longe barbato 3-4-plo brevioribus ; stigmate didymo hir- tello ; fulliculis gracilibus continuis. — Arizona, Dr. Palmer. Described from specimens raised from seed collected by Dr. Palmer. Inter- mediate in appearance between A. tomentosa, which is sometimes gla- brous, and A. longijlura. The stigma consists of two tliick lobes, which are distinct almost down to tlie reflexed ring or collar. The eastern species, reducible to two, have a depressed-cajjitate stigma, truncate and entire at the apex.

PiiiLiBEETiA ToRREYi. Velutino-pubesccns ; foliis cordato-lan- ceolatis vel sagittatis acuminatis ; pedunculis folia a^quantibus 10—15- floris ; corolliB ut videtur albai (lin. 8-9 diametro) lobis late ovatis obtusis extus puberulis villosissimo-ciliatis pedicello parum brevioribus ; columna filamentorum vix ulla. — Sarcosleinma eleffcins? Torr. Bot. Mex. Bound. 1G2, non Decaisne. — S. W. Texas, Parry, ]>igelow. P. elegans is less pubescent, has smoother corolla variegated with pur- ple witliin, narrower lobes, and a manifest column. P. cynanchoides (Sarcosteinma cynanchoides, Decaisne in DC.) is a variable species, with smaller and more numerous flowers, on longer filiform pedicels, the smoothish corolla barely ciliate. P. linearis is a variable low species, of which Sarcostemma heterophyllum, Engelm., appears to be a form approaching the narrowest-leaved P. cynanclioides ; and var. hirtella (^Sarcostemma, Bot; Calif), a narrow-leaved and pubescent form, the leaves rarely auriculate or cordate at base. P. viminalis

OF ARTS AND SCIENCES. ' 65

(Asclept'os vuninolis, Swartz) appears to be the most proper name for the Sarcostemma Brownii (not Bi-oivnei) of INIt-yer and Grisebach, S. claitsnm of Decaisne, mainly, and /S*. crassifolium of Chapman P. undulata (^Sarcostemma unduhitum, Torr. 1. c.) is our only species with a conspicuous column, somewhat longer than the tumid scales of tlie stamineal corona.

ASCLEPIAS, &c. In elaborating this genus and its allies for the North American Flora, the limitation of the genera has to be consid- ered. More than thirty years ago this work was done by the excellent Decaisne for De Candolle's Prodromus, evidently in a hunied way ; Dr. P^ngelmanu and the late Dr. Torrey have |)ublislied important details; and the former has supplied me wiili full notes and many sketches of his elaborate studies, which, unfortunately, have for a long time remained unpublished. For his I'erent elaboration of the whole order in the new Genera Plantarum, Mr. Benthain could not critically examine all the species. Had he done so, he would probably have either re-established Nuttall's Anantherix (as Dr. Engelmann in his notes long ago proposed), or he would have remanded it to Asclepias. The process of the hood, s[)ecially ciiaracteristic of this last genus, although generally corniform, not vei-y rarely takes the form of a pointless crest or plate, like that which in Ananthertx divides at least the upper part of the cavity. Then Acerates angustifoUa (Polyotus, Nutt.), as Nuttall intimated, has the technical character of Asclepias in a reduced form. I think I have found a character in the anthers, which may be turned to useful account; and it may be of no disadvan- tage that, while distinguishing Acerates from Gomphocarpus (the latter sufficiently heterogeneous without the addition of the former), it helps to separate Nuttall's original Auantherix (the anomalous Asclepias connivens of Baldwin) from the two more common sj)ecies which Nuttall long afierwai'ds added to it, along even with Podustigma, his Stylandra.

I venture to rearrange the genera in question, in the manner pro- posed in the foot-note.*

* SYNOPSIS. A. CucuUi coronae basilares intus nmli, ab antheras longe remoti. PoDOSTiGMA, Ell. Coroilae lobi campanulato-erecti. Colunina staminea praelonga. Antherarum alse triangulares basi lata truncata.

B. CucuUi (aut basilares aut in columna brevi pi. m. elevati) antlieris prox- imae : corolla rotatopatens vel reflexa. •

* Cuculli intus processu dorsali vel subbasilari corniformi seu cristseformi aucti.

VOL. XII. (n. S. IV.) 5

66 ^ PROCEEDINGS OF THE AMERICAN ACADEMY

To obviate confusion or mistake wliich may arise as to the priority of Elliott's names over those of Nuttall, it sliould be recorded that, al-

AjTANTiiEnix, Nutt. (Gen.) Corolla sub anthesi reflexa. Columna sub cu- cuUis brevissima. CucuUi adsurgentes, corollEe aequiloiigi, antlieras longe supe- rantes, oblongoclavati apice incurvo, a latere compressi, praeter niarginem ventralem anguste apiceque dilatato bilamellatum solidi, crista obtusissima inclusa. Aiitlierarum alae ntembntnacere, deorsum valde dilatatfe, latissimas, basi liorlzontaliter tnincatffi. Caudiculaj capillares poUijiiis oblongis 2-8 j)lo longiores ! Folia opposila. — A. connivens. A. viridis, Nutt. Gen. excl. syn. Asclejiins viridis, Walt.

AscLEPiODORA. Corolla rotato-patens. Cuculli basilares coluninfpbrevissimae totffi inserii, patenti-adsurgentes, calceolifornies, prorsus cavi, versus apicem crista lamellitbrmi quasi bilocellati. Antlierarum alas corneae basi pi. ni. angus- tat£e. Cnudicula polliniis pyr'forinibus breviores. Folia sjei)ius alterna. — A. VIRIDIS. A^chpias viridis, Walt. Anantherix jmnicidafmt, Nutt. Trans. Am. Plul. Soc. V. 202. ulcerate joa/ijc((/a/a, Decaisne. — A. decumuens. Anantherix decurnhens, Nutt. 1. c.

Asclepias, L. Corolla sub anthesi fere semper reflexa. Cueulli intus pro- cessu c'oriiifonni vel crista^fornii audi. Antlierarum alfe corneiB deorsum usque ad basim truncatam seu late rotiindatam dilatatae. Folia sanpius opposita.

* * Cuculli intus prorsus inappendioulati : corolla sub anthesi reflexa.

AcERATES, Ell. Cuculli involuto-concavi, intus aperti. Antlierarum alae medio vel supra medium (nee basi) dilatatae vel angulatce. Folia sa^pius alterna vel subalterna. Cfet. Aschpiadis.

ScHizoNOTUS. Cuculli saccati, ovales, intus toto longitudine columnae ad- nati, extus longitudinaliter bivalves. Antherae, etc., Aceratis. Folia opposita. — S. PURPURASCENS. Goinpliocarpiis purpuruscens, Gray, Bot. Calif, i. 477.

GoMPHOCARPUS, R. Br. Cuculli intus vel apice aperti. Antherae, etc., Ascle- piadis.

ASCLEPIAS, L.

An American genus except for two African species, mainly North American. I do not see the way to a really natural arrangement of our species ; but the following may serve as a key to them.

§ 1. Cuculli sessiles, nee basi attenuati: antlierarum alae basi latae angulato- truncatae vel auriuulato-deflexae, rarius rotundatae.

* Corolla cum corona aurantiaca : folliculi nudi in pedicello decurvo arrecti : folia pleraque alterna vel sparsa : herba non lactescens !

A. TUBEROSA, L., et var. decumbens.

* * Corolla laete rubja vel purpurea : folliculi nudi, in pedicello decurvo arrecti,

A. Curassavica & A. incarnata exceptaj.

-1- Cuculli aurantiaci : columna sat longa : herbae glabrae.

A. CcRASSAvicA, L. Naturalized if not native in Florida, &c. ; now widely dispersed over the tropical coasts.

A. PAL'PERCULA, Michx. A. lanceolata, Walt., a name which might be restored.

OF ARTS AND SCIENCES. 67

though the first volume of Elliott's work bears the date of 1821 upon the title-page, the first fasciculus was issued in the year 1816, and re-

•t- •«- Cuculli purpurei vel purpurascentes : urabellae multiflorae.

A. KUBRA, L., wliich is founded on Clayton's no. 263 in Gronov. Fl. Virg., with uppermost leaves accidentally alternate.

A. PURPURASCENS, L., founded on Dill. Elth. t. 28, and Herm. Parad. Bot. 33. A. amana, L., founded on Dill. Elth. t. 27, not of herb. L., which is A. vari- egata.

A. iNCARNATA, L., With var. PULCHRA, Pcrs., and var. longifolia, the latter a Texan and New Mexican narrow-leaved form.

* * * Corolla et corona viridulae, flavescentes, albae, nunc sordide vel pallide purpurascentes.

^ Foiliculi processibus mollibus echinati, crebre tomentosi, turgidi, in pedicellis defle.xis arrecti : plantse tomentosae.

A. SPECiosA, Torr. A. Donglasii, Hook. A. CoRNUTi, Decaisne. A. Syriaca, L.

-t- ■*- Foiliculi rostro tantum parce verrucoso-echinulato : herba glabra.

A. S0LLIVANTII, Engelm.

-I- -1- -f- Foiliculi laeves, aut glabri aut tomentulosi,

■w- In pedicellis deflexis vel decurvis arrecti.

= TJmbella in pedunculo elongato caulem siniplicem terminante solitaria : folia arete sessilia seu amplexicaulia : plantse gluberrimae glaucescentes.

A. OBTL'siFOLiA, L. A. purpurascens, Walt. Car. 103.

A. Meadii, Torr. in Gray, Man. ed. 2, addend. ; ed. 5, 397.

= = Umbellae in caule elato 2-4 ; pedunculis folia lata oblonga aequantibus vel superantibus : herba praeter inflorescentiam glabra.

A. GLAUCESCENS, HBK. Specimens of this Mexican species were collected in S. \V. Texas, and referred in the Botany of the ]\Iexicun Boundary Survey to A. Sitllicantii.

^ = = Umbellae pedunculo caulibus abbreviatis foliisque orbicularibus longiore.

A. nummularia, Torr. Bot. Mex. Bound. 163, t. 45.

= = = = Umbellae 2-8 vel plures, raro solitariae ; pedunculis (A. cinerea ex- cepta) folia baud superantibus.

a. Folia lata seu latiuscula, sat magna : cuculli lati antheras vix parumve superantes : caules dodrantales ad 4-pedales.

1. Herbse glabrae vel primum puberulaj, nunquam floccosffi.

A. CRTPTOCERAS, Watsou, Bot. King, 283, t. 28. Sat humilis, decumbens, rotundifolia; cucuUis saccato-ovatis apice bi-aouminatis cornu includentibus.

A. AMPLEXiCACLis, Michx. Decumbens; foliis carnosulis cordatis amplex- antibns ; cucuUis obovato-truncatis, cornu fere incluso. — A. humistrata, Walt., " floribus rubris " exceptis.

68 PROCEEDINGS OF THE AMERICAN ACADEMY

issued, with the second fasciculus, before the close of that year ; aud the third and fourth appeared before November, 1817, — the latter

A. Jamesii, Torr. Adscendens, subpedalis, prinium farinoso pubera ; foliis orbiculatis sen late ovalibus crassis ; cucullis latis apice truncatis, cornu cristae- fornii falcato parum exserto.

A. rHYTOLACCOiDES, Pursh. Glabra, 4-5-pedali8 ; umbellae laxae pedicellis filiformibus elongatis; corolla vlridula; cucullis albis vel subroseis eroso-trun- catis angiilis internis in dentein longe productis, cornu erecto tenui-subulato exserto. — A. nivea, Bot. Mag. t. 481, non L.

A. VARiEGATA, L. Glabra vel glabrata, l-2«pedalis ; unibellis compactis brevi-pcdunculatis ; corolla alba basi cucullisque vijntricosis purpureo tiiictis ; cornu falcato-subulato breviexserto. — Founded wholly on syn. Dill. & Pluk. A. nivea, L. in part, as to syn. Gronor. & herb.

2. Tomentosa vel pubescens : umbellae laterales brevi-peduneulatae : flores viri- duli : cucuUi truncati : folliculi tomentosi vel canescens. Cismontanse.

A. TOMENTOSA, Ell. CuculU in columna brevissima antheris breviores, pro- cessu vix exserto.

A. ARENARiA, Torr. Bot. Mex. Bound. 1G2. CucuUi antheras superantes, processu horizontaliter exserto.

3. rioccoso-Ianuginosae vel canescentes, demum nunc glabratse; caules robusti:

folliculi ovati. Ultramontanae.

<=> CucuUi erecti apice horizontaliter truncati : herbae pube brevi sen lana adi)ressa primuni dcalhatae : umbellfe peduneulataj, pedicellis lanuginosis.

A. Fremonti, Torr. Pacif. R. Rep. vi. 87, sine char. Canescenti-tomentosa vel pubera; foliis ovalibus vel oblongis obtusis retusisve nunc subcordatis petiolatis, margine lasvi ; coroUae albidae lobis oblongo-ovatis ; columna brevis- sima; cucullis antheris aequilongis marginibus anti^e in dentem productis, pro- cessu lato apice suhulato inflexo parum exserto. — >«orthern California, Fremont, Newberry. Not since met with.

A. ehosa, Torr. Bot. Mex. Bound. 162. A. leucophi/I/a, Engelm. in Am. Nat. ix. 349; Gray, Bot. Calif, i. 476. — This species proves to have bien tirst described by Dr. I'orrey, on a glabrate state of the plant which, in the younger and white-lanuginous condition, appropriately received from Dr. Eiigelmann the name of A. leucophijlla. Completely glabrate speciinens have since come in. The rough erosion of the edges of the leaves, to which the original name refers, is evident in all the specimens.

o o CucuUi ventricosi, processu lato incluso : herbae lana longiore floccosa vestitae. Californicae.

A. eriocarpa, Benth. Umbellas pedunculatae.

A. vestita. Hook. & Arn. Umbellae laterales sessiles.

b. Folia angusta, glabra ; caules humiles ramosi : cuculli obtusi antheris breviores vel paullo longiores : folliculi ovati : umbellse pauciflorte.

A. BRACHYSTEPHANA, Engelm. in Torr. Bot. Mex. Bound. 163. Cuculli brevissimi.

OF ARTS AND SCIENCES. 69

containing the genera in question. Nuttall's Genera of North Ameri- can Plants appeared as a whole in the year 1818, the copyright bearing the date of April 3 of that year.

A. iNVOLUCRATA, Eiigehii. 1. c. Uiiibella foliis quasi involucrata.

c. Folia angustissiina : caules huniiles insigniter ramosi: cuculli lanceolato- subulati longissimi, basi eoncavi.

A. MACROTis, Torr. Bot. Mex. Bound. 164, t. 45. A peculiar species.

d. Folia ovata seu oblonga, pubescentia vel glabella : caules erecti 1-2-pedales : cuculli oblongi, antheris 2-3-plo longiores, apice iategerrimo rotundato.

1. Cuculli involuto-concavi, supra medium a processu corniformi apice incurvo vel inflexo exserto liberi : foUiculi toruentosi vel pubescentes.

A. ovALiFOLiA, Decaisne in DC. A. variegntn var., Hook. Fl. Bor.-Am. ii. 252, t. 141. A. Nuttallitna, Gray, Man. ed. 2, non Torr. — Tlie habitat, " Cali- fornia," assigned to tiiis si^ecies by Decaisne, stood in the way of its identifica- tion. Tlie following, from a more south-westerly district, which I confounded with it, appears to be quite distinct.

A. Hallii. Puberula, niox glabrata : foliis crassiusculis ovato-seu oblongo- lanceolatis subacutis basi rotundatis brevi-petiolatis, costa valida, venis leviter adsceiulentibus rectis subtus proniinulis : umbellis multifloris paucis corymbosis pedunculatis ; corollse viridiilo-albae purpiirascentis lobis oblongis : cucuUis elon- gato-oblongis inteyerrimis basi liastato-bigibbosis cornu sicajfornie parum super- antibus. — .1. oral ifoliu, Gray in Proc. Acad.Philad. 1863, 75. — Colorado; near Denver, E. Hall, no. 480. Upper Arkansas River, T. C. Porter. In aspect this most resembles A. Snllirainii. The follicles are not known; but the anther- wings are destitute of the corniculations at the basal angle which are conspicu- ous in the latter species.

A. OBOVATA, Ell. Sk. i. 321. A well-marked species, with somewhat the aspect of Acerates viridiflora. The anther-wings are manifestly bicorniculate at the salient basal angle. Tlie hoods are dorsally somewhat hastately bigibbous above the short contracted base, and from the gibbosity are narrowly wing- appendaged upward and inward for some distance : the inner margins of the hood entire, straight, and so involute as to meet vertically for almost tlie whole length : at the very base inside is a pair of short and roundish fleshy internal auricles. The abruptly inflexcd apex of the horn is subulate and traversed with a dorsal groove or channel.

2. Cuculli a latere complanati, solidi, margine ventral! petaloideo-bilamellato, lamellis semi-obovatis, parte dilatata cristam subconformem eroso-trun- catam includente, angulo interno processu subulato breviter exserto api- culato.

A. NYCTAGiNiFOLiA. Scabrido-puberula ; caule ut videtur pedali adsurgente : foliis ovatis subrhombeis basi in petiolum sat longum contractis, venis adscen- dentibus : umbellis axillaribus 4-8-floris brevissime pedunculatis ; pedicellis petiolo a?qni!ongis ; corolla viridula semipollicari, lobis oblongis ; cucullis erectis antheris subtriplo longioribus : columna sub corona vix ulla : antherarum alls

70 PROCEEDINGS OF THE AMERICAN ACADEMY

Melinia angustifolia. Fere glabra, subvolubilis ; caulibus fili- formibus ; foliis angustissime linearibus petiolatis ; pedunculis brevibus

basi rotundatis. — Rock Spring, Providence Mountains, S. E. California, Palmer, 1876. — Belongs, with the preceding and tlie following, to the Oturia section of Kuntli and Decaisne ; but with a pecuhar hoot!, not unlike that of A. Cuii/teri (infra) and certainly much like that of the original Anantherix. The crest is produced at its internal angle into the horn which is the distinguishing mark of Ascle/ikts.

■M- ++ Folliculi in pedicellis recurvis patulisve penduli vel patentes : caules elati junciformes, foliis subulato-fihformibus delapsis nudi : cucullis panduratis erectis antheras longius superantibus: processu cristjeformi adnato intus bre- vissime cornuto.

A. SUBULATA, Decaisne in DC. 1. c. ; Torr. in Pacif. R. Rep. v. 3iJ2, t. 7. — This remarkable Asdepius of the S. Californian and Arizonian desert appears to be tiie Mexican species briefly described by Decaisne; but a comparison of specimens should be maile.

•M- ++ ++ Folliculi (tamquam noti) in pedicellis adscendentibus erecti, stepius fusifornies.

= Folia lata plerumque quaterna : flores roseo-albi.

A. QUADRiFOLiA, L. A pretty species, with the middle leaves almost always in whorls of four.

= = Folia lata vel latiuscula opposita, nee vertieillata: flores parvi albi.

A. PERENNis, Walt. A. parviflora, Ait., published one year later. A. dehilis, Michx , partly confused with A. qiiudnfolid, to which the "Obs." relates. Towards its northern limits this species conimonl}- wants the coma to the seeds. — Var. PAKVULA is a low and remarkably small-leaved form of the species, from \V. Texas, mentioned by Torrey in Bot. Mex. Bound. 104. — The two following related species are not known to occur within the United States; and the last by its narrow leaves would belong to the next division. They are introduced in reference to the synonymy.

A. xivEA, L. (n(jn herb., but {\\q Apocipium Pevsicnrm j)u7('s, etc., Dill. Elth. t. 29, and A. Ainericannm, etc., Plum. t. iiO, on which the species was founded), Griseb. Fl. W. Ind. 419, excl. syn. Bot. Mag. (which belongs to A.pIi'/toluiToides), is West Indian, and probably not in Louisiana, to which Grisehach credits it. It is distinguislied from A. )>eren>iiti by the greenish-white corolla, longer hoods with shorter horn, and an undulation near the base of the anther-wings, at least when dry.

A. viRGATA, Lagasca, Gen. & Spec. 14, is Mexican, and resembles the pre- ceding in the flowers; but the petals are wiiite, or sometimes rose-iinled (as in Brit. Fl. Gard. ser. 2, t. 8.5), the anther-wings plane, and the leaves linear or linear-lanceolate and less petioled. From Kunth's character (but not that of Decaisne) it may be the A. Unifolia, HBK. I have seen only cultivated speci- mens, under the name of A. angustifolia and of A. linearis.

===== Folia angusta sen angustissima (elongato lanceolata ad lineari-fili- formia), in sp. nonnuUis vertieillata, in unica alterna.

OF ARTS AND SCIENCES. 71

bibracteolatis pleruraque unifloris nunc geminis ; corolla campanulata fere 5-partita sepalis lanceolatis acuiuiuatis parum longiore, lobis

a. Corolla reflexa generis : cuculii cornusubulato exserto instructi. 1. Colurana sub cucuUis conspicua, antlieris parum dimidlo brevior.

A. Mexicana, Cav. Ic. i. 42, t. 58. A. fascicularis, Decaisne in DC. A. macrop/ii/!la, Nutt. PI. Gamb. 180. This species, which is common from Oregon to the borilers of Mexico, appears to be identical with specimens collected in the valley of Mexico by Bourgeau (no. (33), and by Ghiesbreght still farther south. The figure in the Icones of Cavanilles very well represents it.

A. VERTiciLLATA, L. A widely distributed species, including ^4. galioides, HBK., of Me.xico. Var. pu.mila is a singularly dwarf or depauperate form, of the western dry plains, from Nebraska to New Mexico. Var. suBVERriciLLAXA (A. verticillata \a.r. galioides, Torr. Dot. Mex. Bound. 164, chiefly), is a marked form, with single stems, simple or branched, the leaves mostly in pairs and threes, and their margins little revolute, the horns of the hoods rather less ex- serted. Decaisne's A. verticillata var. lini folia may include this ; but it is evi- dently a mixture of A. verticillata (to wliicli the specimens from "Florida and Georgia" mny belong) ; of A. virijala, L;ig. {A anf/astifolia, Roeni. & Scliult. &c.), which, from Kunth's character of opposite leaves and little exserted horn, may be A. UnifoUa, HBK.; and of ^1. Mexicana, Cav. (from which may come the character of leaves 4-6-nate), which must be identical with A. fascicularis of Decaisne. Here also A. linearis, Scheele in Linntea, xxi.

(A. LiNARiA, Cav , a Mexican species which has been associated with A. vet- ticillnta, differs much in the very short stamina! column, short and almost included horns, and in the ovate follicles becoming erect on the docurved pedi- cel, which is not known to occur in any species of this section.)

2. Columna brevis crassior.

A. QUINQUEDENTATA. Facie fere A. verticillatce var. suhverticillntK ; foliis omnibus oppositis angusto-linearibus elongatis; umbellis paucifioris longiuscuhi pedunculatis ; corollas virescenti-alb£e lobis ovalibus (lin. 2|-3 longis) ; cucuUis antlieris aequilongis columna triplo longioribus complicatis, dorso subcarinato, apice truncato grosse argute 5-dentato ; processu falcato ad apicem cucuUi usque adnato ihiqiie bifido, lobo dorsali minimo dentiforiin, ventrali in coriiu suljula- tum inflexum breviter exsertum producto. — W. Texas, on or near the San Pedro River, C. Wright, no. 1689, referred in Torr. Bot. Mex. Bound. 104, to a variety of A. verticillata. It is much more related to the appended Mexican species.

(A. CoDLTERi. Praecedenti affinis ; foliis oppositis filiformibus ; umbellis 3-6-floris ; pedicellis filiformibus pedunculo subaequilongis ; coroUae albse lobis oblongis (lin. 3— t longis) ; cucullis columna crassa triplo longioril)Us antheras aequantibus complicatocorapressis subquadratis dorso carinatis centro solidis apice truncatis subintegris; processu lato-subulato falcato infra apicem cuculli libero integerrimo longius exserto. — Mexico, Coulter, coll. no. 983. Single specimen, in flower: fruit not seen. The horn of the hood springs from a solid central portion, which is winged dorsally by a keel; the ventral part and top bilamellar and open.)

72 PROCEEDINGS OF THE AMERICAN ACADEMY

lanceolatis apice crassiusculo recurvo intus piiberulis basim versus penicillato-barbulatis : corona phyllis spathulato-oblongis planis crassi-

A. ANGUSTiFOLiA, Ell. Sk. i. 325, 1817. A. tuberosa ? Walt. Car. fide Eil. A. Michanrii, Decaisne, 1. c. : so named because a specimen in Micliaux's herba- rium is mixed with his A. longifolia ; but Elliott's specific name has priority of all homonj'ms. The narrow and elongated thickish leaves are mainly alternate, which marks the species.

A. viRiDULA, Chapm. Fl. 302. A well marked species, with opposite and very narrow leaves, most resembling tlie following ; but with smaller yellowish- green flowers, and hoods considerably exceeding the anthers and the horn. — Found only in the vicinity of Apalachicola, Florida.

3. Columna sub cucuUis nulla : folia opposita.

A. ciNEREA, Walt. Well distinguished by the few-flowered lax umbels, and short very obliquely dorsally truncate hoods, the ventral cusps of which surpass the broad-triangular horn.

b. Corolla cum calyce rotato-patens, nunquam reflexa : crista mutica adnata in cucuUo.

A. Fkayi, Chapman in litt. A. cinerece subsimilis ; foliis fere filiformibus longis patentissirais ; umbellis terminalibus et subterminalibus brevi-peduncu- lat'is paui'ifloris ; corolla alba majuscula explanata ; cucullis etiam albis prajter costam petaloideis oblongis integris involuto-concavis antheris aequilongis sed patenlibus intus dorso medio lamella semiovali integerrima instructis. — Tampa, Florida, Dr. Leavenworth (a single specimen in herb. Torr., collected 40 jears ago), Dr. Wm. T. Feay, Dr. A. F. Garber. Dr. Chapman proposed to call this an Acerates, but in my view it is clearly an Asclepias.

§ 2. PoDOSTEMMA. CuculH stipitati, erecti, stipitibus antheraslonge superanti- bus basibus columnae adnatis, lamina spathulata intus cristata, crista insequal- iter bicorniculata : antherarum aliB medio latiores et subangulatae.

A. i.oNGicoKNU, Benth. A. Litidhrimerl, Engelm. & Gray. — Ranges from Texas to Nicaragua. Follicles arrect on the deflexed pedicels.

§ 3. NoTHACERATES. CuculU sessiles, oblongi, apice bidentati, intus crista angusta jjrorsus adnata e sinu corniculato-excurrente : antherarum alffi deorsum dilatat;B, supra basim late rotiindatam auriculatoemargiiiatfe : pol- linia arcuato-obovata. Habitus Acerutis aiiriculuke.

A. STENOPHYLLA. Poli/otiis nnf;iistifi>liiis, Nutt. in Trans. Anier. Phil. Soc. v. 201. Acei'iti's angustifoUa, Decaisne in DC. 1. c. Nuttall noted the clear transi- tion to Asclepias.

ACERATES, Ell. « Gynostemium subglobosum : columna sub cucullis brevibus manifesta : folia pleraque allerna.

A. AURicuLATA, Engelm. in Bot. Mex. Bound. 160. Foliis preelongis ang s- tissimis umbellisque ^.sc/«=/»Vu/t stenophylhe simillima; cucullis basi late auric i- latis ; antherarum alls angustis utrinque sequilatis.

OF ARTS AND SCIENCES. 73

usculis inappendiculatis basi coroUae et columnne longiusculae insertis corolla dimidio brevioribus ; rosiro stigmatis gracili iutegerrimo mem- braiiam aiitlierurum erectam pauUo superante. — Metai>telina? angusti- fuliu/n, 'I'orr. Bot. Mex. Bouud. 159. Ravine at Santa Cruz, Sonora, Mexico, very near tbe southern boundary of Arizona. Instead of constituting a new genus for this species, it is here referred to the extra-tropical South American genus Melinia, on account of the long and slender beak to the stigma, corolla-lobes distinctly but narrowly dextrorse-convolute, narrow sepals, &c. It is excluded from Oxypetalum by the absence of any tooth" or appendage to the caudicles of the poUinia. The corona is attached rather more distUictly to the corolla than to the cclumn. and the pieces are wholly distinct and rather widely separate ; but a slight ridge at the base of each is decurrent into a slightly salient line on the column. The latter is about the length of the body of the anthers, w^hich, again, bear a still longer erect mem- brane, ovate-oblonoj in form.

MetastiiLma Blodgetti. Eiimetastehna : caulibus filiformibus ; foliis parvis anguste lanceolatis ; pedunculis 3-6-floris pedicillis (lineam lonois) et petiolo brevioribus vel nullis ; corolke 5-partitae lobis obloiigo-lanceolatis iutus sub apice peuicillato-barbatis : coronge

A. LONGiFOLiA, Ell. Columna pauUo longiore ; ciicuUis ovalibus intejierrimis inappendiculatis niarginibus ventralihus medio coluninte adnatis antlieris di- midio brevioribus ; antiierarum alis senii-rliombeis basi niagis attenuatis.

* * Gyiiostemiuni longius quam latum : cucuUi oblongi parum breviores, basi bus columnam brevissimam tola longitudine obtegentibus : folia latiora saepe opposita.

A. LAXUGixosA, Decaisne. Als antherarum paullo infra medium latiores subangulatai.

A. viRiDiFLORA, Ell. AIsB autlierarum versus apicem latiores subangulatae, basi longius angustatse.

GOMPIIOCARPUS, R. Br.

This genus is briefly defined as Asclepias without any crest or horn in the hoods. E.xcept for two ai>pended Californian species, which technically belong to it, it would be restricted to the Old World, mainly to Africa.

G. TOMEXTOsus, Gray, Bot. Calif, i. 477 {Acerates lomentosa, Torr.),has wholly tlie aspect and the structure of Asclefjias vestita, of the same region, except as to the hoods, which are spreading or even depending, so that the (juasi- bivalvular opening is superior or in appearance dorsal, giving a resemblance to the structure in the plant which I named G. purpurascens, but am now obliged to separate genericall y.

G. coRDiFOLius, Benth., except for the want of horn, would be an Asclepias, related to A. phytolaccoides.

74 PROCEEDINGS OF THE AMERICAN ACADEMY

Bquamis termi-subiilatis imae basi corollas insertis antheris cum columna breviore (sed manifesta) adaequantihus. — M. parvijioruin, Cbapm. Fl. 367, non R. Br.— Pine Key, S. Florida, Blodgett.

GONOLOBUS and LACHNOS TOiAIA. Later autbors generally appear to liave taken tbeir idea of Gouolohus from tbose numerous tropical speoies wbicb ditler considerably from tbe typical ones of tbe Soutliern Atlantic States. Tbe latter have not the coloied-reticulated corolla of most of tbe tropical species, nor tbe broad and rounded lobes of many of them, nor tbe strongly salient-angled stigma, which has been made a part of tbe generic character, nor is the corona borne on tbe corolla, but either distinctly on tbe short stamineal column or at its very base at tbe junction with tbe corolla. Laclmosfoma^ 11 BK., was founded on a single and peculiar species, with " corolla subbypo- crateriformis," or at least with tube as long as the limb, and with "corona pentapbylla, fauci coroUte inserta, foHolis cuneatis carnosis apice lunato-bilobis," etc. Noting that tbe column of (llatnents is aduate to tbe tube of tbe corolla (as it truly is for tbe whole length), Kunth, indeed, adds the query : '' An igitur corona summo tubo fila- mentorum nee fauci coroUae inserta?" But the flowers I have exam- ined, from Fendler's no. 1050, show that the first view was tbe correct one. On separating the tube of the corolla from that of the filaments, almost without lesion, the coronal appendages are left on tlie former, to which they manifestly belong. There are, moreover, vestiges of a stamineal corona, in tbe form of minute scale-like processes, one under tbe base of each anther. Decaisne adds three other species to the genus, and characterizes it by the " corona staminea gynostegio plus minusve adnata, pentapbylla." It will be allowed that, if tbe genus can stand upon tbe 5-pbyllous corona, tbe mere insertion will be unimportant. But Mr. Bentbam, enlarging the genus much more by adding Decaisne's Ibutia and Chthamalia, includes species with cup- shaped and wiih annular corona, thus resting LacJmostoma mainly ou tbe insertion of this oi'gan, which is variable from species to species, and really not different fi'om that of typical species of Gonolobus. And our only reticulate-petaled species of the latter bears the annular corona distinctly on the column, close to its base, but wholly separate from the corolla. It thus appears, on tbe whole, that LacJmostoma should be restricted to the original L. tigrinum ; and that CJdhamalia (as the subjoined details show) should form only a subgenus of Gono- lohus. Those reticulate-flowered tropical species (of which we have one, not very typical, representative in Texas), with all its variations in the gyuostemium and corona, may form another section, which may

OF ARTS AND SCIENCES. 75

conveniently take the name of Dicfyolohus, using here the Greek word in the sense of lobe, instead of pod.

The North American Gonolobi, of the Atlantic United States, are confused and dilfitnilt, partly because flower and fruit have seldom been had from the same plant. The subjoined conspectus gives the result of my study of the present available materials, aided by notes and sketches from Dr. Enoelmanu. *

* GONOLOBUS, Michx. Fl. i. 119.

§ 1. DiCTTOLOBUS. Corolla rete subtili conspicuo saepius colorato venosissima, nunc rugulosa ; lobis plerumque hitis. ilores in nostra parvuli, in pleris majusculi.

G. RETicuLATUs, Engelm. Mss. G. qramtJntna, Torr. Bot. Mex. Bound. 165, non Scheele in Linnsa. — Texas and adjacent borders of Mexico. Well described (except as to antlier-tips, which really overlie the edges of tlie stigma), but wrongly referred, by Dr. Torrey. Scheele's description of the peduncles as shorter than the petiole, the pedicels as barely equalling the flowers, and the lobes of the corolla as lancei)late-attenuate from a broader base, is incompatible with the present species, and relates to a variety of G. Items, Michx.

§2. EcGONOLOBUs. Corolla baud reticulata, lobis angustioribus : corona sim- plex, intus inappendiculata, columnae basi sspius iuserta : stigmatis anguli parura prominuli : caules herbacei.

* Pedunculi pauci-pluriflori : corolla 5 partita, rotata, patentissima,

••- Crassiuscula, viridula, extus cum calyce pedunculo brevi pedicellisque gla- bra : corona sub gynosteraio pateriformis undulatocrenata, carnosa : antherae membrana tenuiter scariosa super marginem stigmatis inflexa : folliculi laeves 5-angulati.

G. suBEROSus, R. Br. Ci/nanchum, L. Hort. Cliff. 79 (excl. syn. Apocymim scandens fruticosum finnioso coiiice BrasiUamuii, Herm. Parad. 53), & Spec. 212, excl. syn. Gronov. Periplocn Carnllnensis, etc., Dill. Elth. 300, t. 229, f. 296. G. macroplii/llus, Chapm Fl. 368. Corolla in alabastro late conica, lobis ovato-trian- gularibus a basi sensim angustioribus acuminatis supra albido-hirsutulis nunc glabratis. — Although Hermann's Brazilian plant, referred to, suggested the name, we may consider the Linnaean species as founded on the Dillenian plant, the figure of which very well represents what we take for this species. More- over tlie Grouovian synonym belongs to G. hirsidns or G. Camfinensis. De- caisne's G. siiber<>s>is, with ovate pubescent sepals, and corolla glabrous within, must be some quite other species.

G. l;evis, JMiclix. Fl. i. 119. Minus pilosus vel glahellus ; nmbellis 5-10-floris petiolo vix aequilongis: foliis oblongo-cordatis ; corolla in alabastro elongato- conica, lobis lanceolatis sen lineari-lanceolatis glabris ; folliculis laevibus 5-angu. latis. — Mississippi to Arkansas and Texas. Pursh introduces some confusion by adding a wrong synonym, and a consequent misstatement of the color of the corolla. It passes freely into

76 PROCEEDINGS OF THE AMERICAN ACADEMY

GiLTA (Dactylophyllum) Parry^. Pygmaea, floribunda, pubes- cens ; caule e radice annua nunc vix semipollicari floiibus breviore nunc demum bipollicuri a basi confertim ramoso ; foliis plerisque oppositis 5-7-partitis, segmentis acerosis (lin. 2-3 longis) ; floribus iu dicbotomiis subsessilibus ; calyce profuude 5-fido corolla fere triple breviore lobis lanceolato-subulatis, tube brevissimo obconico ; corolla aut alba aut sulpliurea aut casruleo-lilacina, tubo brevissimo cum

Var. MACROPHYLLUS. Foliis rotundato-cordatis majoribus (nunc 9-10-polli- caribus), acuniine abrupto, lobis basilaribus rotundatis sinuni sjepe claudentibus, pagina inferiore pube molli brevi nunc granulosa saepius indutis; calycis lobis versus apicem rariter ciliolatis ; foUiculis brevibus angulatis 5-costatis. — G. macrophyllns, Miclix. 1. c. G. viridiflorus, Nutt. Gen. i. 163 ( G. Nuttallii, De- caisne in DC.) G tiluefolius, Decaisne in DC. G. grunulatus, Scheele in Linnaea, xxi. 759. Viiicetoxiciim gonocaipos, Walt. Car. 1U4, pro parte. — S. Carolina to Texas, Kentucky and Missouri. Elliott's G. viacrofiliyllus, with muricate fruit and slender lobes to the corona, must be G. Baldwhiidnus, Ciiapnian's is G. mberosas, and Decaisne's, in the Prodromus, is mainly G. oUiquus. Pursh's addition of " flowers dark purple or dirty yellow " was taken from Walter, who evidently had more than one species under his Vincetoxicuin gonocarpos.

■*- -1- Corolla submembranacea, purpurea, ochroleuca, vel albida : corona cupu- lifoimis, gynosteniio adsequans : niembrana antherarum inconspicua vel ob- soleta : pedunculi saepius loiigiusculi pluriflori, cum calyce pedicellisque pubescentes : corolla extus pi. m. pubera : folliculi teretes muricati. •t-t. Coronae subcarnosae margo tantum crenatus.

G. OBLiQuus, R. Br. Corolla intus sanguineo-purpurea, extus viridula, lobis lineari-ligulatis : corona 10-crenulata, crenulis aitemis angustioribus plerunique emarginatis vel bidenticulatis. — Roein. & Schult. Syst. vi. 64 ; Bart. Fl. Am. Sept. iii. t. 99; Gray, Man. ed. 5, 399. G. hlrsutus, Nutt. Gen. i. 1G3, non Michx. G. macrojihyllus, Decaisne, I. c, non Michx. Goiiolol'ium hirsiitum, Pursh, Fl. i. 179. Cynanchum oblirpnnn, Jacq. Ic. Ear. t. 341. C. discolor, Sims, Bot. Mag. t. 1273. C. hirtum, L. ? quoad Apocynum scandens Virginianum, etc., Moris. Hist. The most northern species, ranging from (Carolina?) the moun- tains of Virginia to Pennsylvania, Ohio, and Kentucky. — Var. Shortii, ap- parently a form with larger (and dull purplish?) flowers, said to exhale the scent of Calycanllttis-h\os,soms : known only in specimens collected by Short and Peter, near Lexington, Kentucky, where it should be re-discovered.

G. HiRSUTUs, Michx. 1. c. Pedunculi pauciflori : corolla intus atro-purpurea, lobis elliptico-oblongis : corona margine obtuse aequaliter 10-crenata. — Virginia and Tennessee to Florida. The corolla in dried specimens by transmitted light shows a reticulate venation more distinctly than any other species of this group.

•w- ++ Corona 5-lobata, dentibus geminatis vel bifidis interjectis : pedunculi pluriflori sublongiores.

G. Carolinensis, R. Br. Corolla badia vel atro-purpurea, majuscula. lobis oblongis seu lineari-oblongis: corona subcarnosa, undiilato-.5 lobata, sinubus processu subulato biiido gynostemio adaequante instructis. — Cynanchum Caroli-

OF ARTS AND SCIENCES. 77

fauce obconico lobis obovatis integerrimis vel erosulis apice saepius cus- pidalis 2-4-plo breviore ; antheris oblongis ; capsula ovali-oblonga polysperma ; semiiiibus angulatis fere cubicis, tegumento externo laxo temii uec spirillifero nee mucilaginoso. — San Bernardino Co., S. E. California, on desert plains near the head of the Mohave River, Parry and Lemmon, also Palmer. A very distinct and pretty little species, in appearance somewhat intermediate between G. dianthoides and a

nense, Jacq. Ic. Rar. t. 342. This from the character should he WaUer's Vince- toxiciim acaidliocarpos, Elliott's G. Carolinensis (excluding the fruit), and probahly (t. kii-suins, Sweet, Brit. Fl. Gard. t. 1. It extends from South Carolina to Louisiana and Arkansas.

G. Baldwixianus, Sweet. Corolla albida vel flavida, lobis oblongis demum subspathulatis tenuioribiis : corona fere membranacea altius fissa, segnientis 5 latis ssepius eniarginatis, 10 per paria interjectis lineari-subulatis duplo longioribus stigma superantibus. — G. »«(;c;o/</(////((s, Ell., non Michx. G. Carolinensis, 'Nutt Gen. i. ItJo, non R. Br. G. Iiirsutiis, Lodd. Cab. t. 305 ? Georgia and Alabama to N. W. Arkansas. Elliott and Nuttall, who describe from dried specimens, speak of the corolla as " obscure yellow " or " yellowish," but Engelmann, who col- lected it in Arkansas, says " wliitisii " ; and Buckley on tlie ticket of his speci- mens in the Torrey herbarium, collected in Alabama, writes "flowers white." This species clearly coimects Poli/stenuiia, Decaisne, with Emjoiiolohus.

* * Flores solitarii subsessiles : antiiera9 etiam Chtliamnlice, sed corona simplex

Eugonolubi.

G. SAGiTTiFOLTus. Plumilis, volubilis, vix puberula; foliis subcarnosis parvis sagittatis, auriculis obtusis : corolla lutea glabra alte 5-tiila, lobis lanceo- lato-linearibus : corona imae basi corollae inserta cyathiforma integerrima; foUi- culis lanceolatis lajvihus. — Rio Limpio, W. Texas, Wright. This is Dr. Torrey's G. parvifolius only as respects the specimen of Wright referred to by him, and from which he describeil the follicle.

§ 3. Chthamai.ia. (ClithnmaUa & Lachnostomatis sytec. Decaisne.) Corolla baud reticulata, campanulata vel rotata, 5 loba vel 5-partita: corona intus cristata vel append iculata, raro (appendici>)us liberis) duplex : antherae prominiilaj a stigmate niagis liberae, marginibus nunc (Asclepiadis modo) alls corneis instructaj. Plantse humiliores saepius parviflores.

* Diffusae, nee volubiles : pedunculi nuUi : pedicelli 2-3 ad axillas fasciculati : folia cordata.

G. PUBIFLORC9, Engclm. PI. Lindh. i. 44; Torr. Mex. Bound. 165. G. prostratus, Baldw. in Ell., non R. Br. Chthatiuilia /nihifloni, Decaisne. — The only species of this section east of the Mississippi, and an ambiguous one. It has exactly the aspect of the two following, except that the campanulate corolla is cleft barely to the middle (in which it is very unlike true Gonolohi), but the cup-shaped crown, which overtops the stigma, is almost simple within, the five crests being attenuated and inconspicuous or even obsolete : there are five minute adnate auricles at the very base. The follicle, which I have not seen. is said to be smooth.

78 PROCEEDINGS OF THE AMERICAN ACADEMY

very dwarf G. dichotoma, rlesirable for cultivation on account of its abundaut and vaiiously colored flowers of comparatively large size for the pygmy growth, the corolla being fully half an inch long, indeed longer than the earlier stems. At the suggestion of Mr. Lemmou, this dainty plant is dedicated to Mrs. Dr. Parry, one of the botanical party who passed the last winter and spring in the San Bernardino district ■ — making many interesting discoveries — and whose services to botany well merit this recognition.

G. BiFLORUS, Nutt. in herb. DC. ; Torr. 1. c. Chthamalia biJJora, Decaisne. In this tlie corolla is rotate and deeply 5 cleft ; the corona tleeply lobed ; and the canaliculate cre.st ailnate to each lobe is connected at base with the cobimn, wliile it terminates above in tlie stout and conspicuous tliickened acumination which incurves over the ed^e of tlie stigma. The follicles, as in the next, are large and muricate. — Var. Wrightii, also from Eastern Te.xas, is a form with the corolla almost 5-parted into narrower lobes, and the cusps of the corona shorter.

G. CYNANCiioiDES, Engelm. PL Lindh. i. 48. has the inflorescence much inclined to be racemose-clustered on a peduncle-like summit of the stem, the upper leaves being reduced and bract-like, the corolla rotatecampanulate and almost 5 parted, and the very obtusely 5 lobed corona is appendaged within by a shorter crest which terminates in a free and blunt apex, shorter than the lobo to which it adheres.

* * Caules Juimiles sed volubiles : fiores (luteoli) subsessiles solitarii, raro

geinini : folia parva, pi. m. hastata.

G. PARViFOLitrs, Torr. 1. c, excl. fruct. The corolla is globose in the bud, deeply 5-lobed, and almost rotate when expanded, the lobes ovate. The fleshy corona is at the very base of the short column; its lobes ovate, spreading, ap- pendaged with a very broad adnate crest, the edge of which at base is united with the column, at the apex extended into a minute iuflexed tooth.

G. HASTur.ATUS. Litc/inostoma hastulatitm, Gray, Bot. Calif, i. G20. In this the corolla is narrowly oblong in the bud, the lobes linear. The corona is of distinct pieces, like the hoods of AsrJe/)ias, and, as in that genus, borne at the summit of the colunm, close under the antliers ; tlie ligule or horn within is prominently exserted and inflexed. Follicle rather slender and minutely muricate.

* * * Caules elongati subvolubiles : pedunculi axillares folio sagittato-cordato

brcviores, unibellato 3-5-fiori : corolla oblongo-campanulata, lurida, inajus- cula (J pollicaris), alte 6-fida, lobis lineari-obloiigis : corona cyatliiformis, 8ub-lobata, intus lamellis 5 columnae adnatis quasi septata.

G. PRODOCTUS, Torr. 1. c. The follicles are ovate and smootli. The species ranges from Western Texas to Arizona, and into adjacent parts of Mexico.

* * * * Pedunculi filiformes folia mox longe superantes, quasi racemoso-pauci-

flori : flores perpusilli: corolla rotata : corona alte lacuiiata, duplex : caulis humilis, a basi ramosissimus, nee volubilis.

OF ARTS AND SCIENCES. 79

GiLiA (Lfptostphox) brevicula. Inter Tenuiforas notabilis tubo corollaj (cajruleae seu violaceae) limbo parum sesquilongiore, foliis brevibus calyceque subglanluloso-liirtellis. — On the INIohuve River, S. E. California, Dr. E. Palmer, 187G. — Stem barely a span liigh, more branching than in G. unJrosacea, which it much resembles; the branches becoming c^nnose. Leaves only 3 lines long ; the divisions acerose-subulate, the j^nbescence short-hirsute and glandular. Tube of the corolla barely 5 lines long, nearly double the length of the calyx and bracts ; the oval lobes fully o lines long. Stamens ex- serled from the very short cyathiform throat. Style exserted: stigmas long and slender, almo>t capillary, fully equalling the lobes of the corolla. The latter appears to have been blue, or violet-purple. The flowers are abundant, and the species would be attractive in cultivation.

GiLiA (Ipomopsis) Haydeni. G. subniidcB affinis, ramosior, fere glabra ; ramulis peduncidis (corymbosis longioribus) calycibusque

G. PARViFLOROS. Lnchnostoma ? pnrviflorum, Torr. 1. c. This remarkable spe- cies closes tlie series. Its principal corona is somewhat Hlce that of G. Bitldwini- anits, which is a genuine Gonolofiits. It is diviileil into five short and broad membranaceous h)bes, wliicti from tiie apex are produced into a pair of slender subulate processes, witii a wide sinus between : opposite eacii lobe within, and separately inserted, is a simihir and longer process, which may answer to the lignle or otiier internal appendage of the foregoing species, become wholly free. Tlie follicle is ovate ami tuberculate-muricate.

(G. PROSTRATUS, R. Br., the Lnchnostoma prostratum of Decaisne, is also a Chtliainalia, with lobes of the corona nearly distinct, each produced into a pair of processes like those of the preceding, but also with a shorter intermediate one, and still another before this, the latter answering to the internal ligule adnate up to the notch of the lobe.)

To Pl//ra»f!tpra — a little known genus, well referred by Bentham (who had not seen specimens) to the Gonolobece, and marked by the direct adhesion of the corona lobes by the whole length of the middle of tlie inner face to the column — there are two Cuban species to add, both with flat-top(ied stigma: viz., —

rxTCANTHERA ACCMiNATA = 0/ i/io.sM acKiiiiiKita, Griscb. Cat. PI. Cubens. 175. In this the Io])es of the deeply G-parted corona are ovate-oblong, attached along the middle only to the whole length of the column, the sinuses rounded and open. Pollinia obliquely short-pyriform, pellucid at the insertion of the caudicle.

Ptycan'tiiera OBLONGATA = OrlJiosin ohlongntn, Griseb. 1. c. Lobes of the disk oblately oval and emarginate, with thinner free edges, the centre adnate to the whole length of the column, wliicli is considerably shorter than in the pre- ceding species, the sinuses somewhat auriculate. Pollinia nearly oblong, strongly arcuate.

80 PROCEEDINGS OF THE AMERICAN ACADEMY

praesertim glandiilosis ; foliis radicalibus pinnatifidis, caulinis parcis brevibus liiiearibus iiitegerrimis ; corolla tubuloso-infiiiidihuliformi gra- cili (^-|-pollicari) hete rosea, tube lobis obovatis 3-4-|)lo longiore ; antheris subsessilibus fauci insertis ; stigmatibus brevisf^imis ; ovarii loculis 6-ovulatis 2-3-spermis ; serainibns obloiigis, testa tenui sub aqua nee spirillifera nee mucilaginosa. — High j^lains of the San Juan, S. W. Colorado or adjacent part of Utah, Braudegee, in Hayden's Exped. 1875.

GiLiA (Ipomopsis?) c^spitosa. Glanduloso-puberula, viscida ; caulibus brevissimis e caudice inulticipiteca3spitante pedunculis ramisve floridis nudiusculis (2-3-pollicaribus) laxe 3-5-floris terminatis ; foliis radicalibus confertis crassiusculis spathulatis vel spathulato-lanceolatis (imis lin. 2-3 longis) obtusissimis, sequentibus longioribus mucronatis, pedunculorum ad bracteas subulatas diminutis ; pedicellis fere nudis ; calycis angusti lobis subulato-setaceis ; ovulis in loculis paucis. — Rabbit Valley, Utah, on barren cliffs of sandstone, at 7,000 feet, L. F. Ward, in Powell's Plixpedition, 1875. The corollas gone, and fruit not formed ; but the plant cannot belong to any already published species.

Phacelia (Eutoca) orisea. Annua, cinereo-pubescens et hirsuta, viscidula : caule ultra-spithamaio a basi ranioso ; ramis patentibus sat validis, hirsutia patentissima rigidiila, pube brevissima densa; foliis ovatis oblongisque integerrimis (semipollicaribus ad pollicaria) brevi- petiolatis cinereo-strigosis ; spicis elongatis densifloris ; calycibus sub- sessilibus, .sejxilis spathulatis patenti-hispidis corolla (alba?) subdimidio brevioribus capsulam ovatam acutam paullo sujoerantibus ; filamentis longe exsertis pills brevibus papillisve retrorsis hirsutulis basi plicis transversis adnatis appendiculatis ; ovulis 10-12; seniinibus 5-6 grosse rugoso-favosis. — On Pine Mountain, back of San Simeon Bay, Cali- fornia, Palmer.

Eritrichium setosissimum. Krynitzhya inter subsect, Pseudo- myosotidemei Pterygium, habitu potius E. glomerati, cinereo-pubescens, hirsutulum, et setis ui'entibus hispidissimum ; caule valido ultra-bipe- dali e radice nt videtur bieuni ; foliis spathulatis sen lanceolatis ; spicis racemoso-paniculatis pauci- et parvi-bracteatis, friictiferis elongatis strictis (4-pollicaribus) ; corolla alba parva (lin. 2-3 longa), tubo lobis rotundatis vix duplo longiore intus versus basin 10-dentato-annulato, fauce insigniter 5-fornicata ; antheris brevi-oblongis ; nuculis pro genere magnis ala integerrima circumdatis (cum ala ovata lin. 2-3 longis) opacis scabriuscnlis, fiicie dorsali parum convexis, ventrali angulo obtusissimo per sulcum angustissimum gynobasi subuliformi aequiloDgae

OF ARTS AND SCIENCES. 81

affixa. — Shores of Fish Lake, Utah, at 8,700 feet, L. F. Ward, in Powell's J^xpedition, 1875. A most remarkable species, which, without the fruit, might be coufouuded with E. glomeratum.

F.RITRICH1UM Hoi.OPTEUUM. Kryiiitzkia, facie E. leiocarpt et E. muriciilati formjB validioris ; corolla fance fornidbus Conspicuis basi tubi appeudicibus parvulis instructis : nuculis omnibus ala an^usta in- tegerrima circumdatis dorso muricatis. — S. Utah, Capt. F. M. Bishop ; Ehrenberg, Arizona, Palmer.

Pectocarta (Gruvelia) ptjsilla. — Gruvelia pusiUa, A. DC. Prodr. X. 118. That most successful plant-finder, Rev. E. L. Greene, sends this Chilian species from the vicinity of Yreka, in the northern part of California, east of the Coast Range mountains, therefore far from the coast. It there abounds in company with the natives of the region, and, as Mr. Greene states, would not be suspected to be other than indigenous.

Pectocarta (Gruvelia) setosa. A prEecedente distiuctissima foliis etc. hispidis ; calyce t^etis paucis validis divaricatis horrido ; nucu- lis majoribus ala latiuscula nunc undulata marginatis undique uncinato- setulosis. — S. E. California, on the desert plains of the upper Mohave River, Palmer.

Lycium gracilipes. Vrscidulo-puberulum ; foliis crassiusculis spathulatis seii oblongo-obovatis (lin. 2-6 longis) : pedicellis pubero- glandulosis folia floralia longius superantibus flori subtequilongis : calyce campaiiulato breviter 5-dentato ; corolla infuudibuliformi " violacea nunc albescente " semipollicari, tubo proprio calycem vix superante, fauce sensim ampliata, lobis 5 lato-ovatis obtusissimis lineam longis ; filamentis filiformibus fauci versus basim iusertis iiiferue villosulis ; antheris sub- inclusis. — Northern Arizona, at Williams Fork (alias Bill Williams' River), Palmer, 1876.

Antirrhinum (Pseudorontium*) chttrospermum. Calycis segmentis oblongo-lanceolatis tubo corollae tequilongis ; cyatho setuinis maximo ollasformi. — Ehrenberg, Arizona. Palmer.

Pentstemon comarrhenus. Speciosi: gracilis, glaucescens, glaber vel foliis (summis linearibus, imis oblongis ovalibusque) minutissime

* Antirrhinum sect. Pseudorontium. Capsula tenui-chartacea subdidy- ma, loculis aequalibus apice irregulariter ruinpentibus Asurinoe. Semina ala pelviforiui niodo Orontii. — Sjiee. 2, Am. Bor.-Occ. Merid. ; foliis alternis petiolatis ovatis integerrimis ; caule erecto ; piibe viscidula ; floribus parvis. A. CTATHiFERUM, Bentli., ex tab. & descr. calycis sefrmentis lineari-lanceolatis tubo corollas multo brevioribus, cyatho seminis niajusculo; & A. chytro- 6PERMUM supra.

VOL. XII. (n. S. IV.) 6

82 PROCEEDINGS OF THE AMERICAN ACADEMY

pruinoso-puberulis ; panicula virgata laxa ; pedunculis pedicellisque loiigiusculis ; sep;ilis ovalibus parvis (liaud ultra liu. 2 longis) ; corolla (pollicari) c«ruIeo-pur|)urea, tubo inferne loiigius attenuato ; antheris longissime lanatis. — Common in Utah, especially southward, coll. by Gordon, ¥.. W. Emef;^on, Mrs. Thompson, Siler, and recently by L. F. Ward. Like P. secundijlorus ; but flowers larger, looser and hardly secund in the panicle; and the anthers long-woolly almost in the manner of P. Menziesii. Still nearer, perhaps, to the le-s-known P. strictus, Benth. ; but that has much smaller and narrower flowers in a crowded inflorescence, acuminate sepals, &c.

Pentstemon Wauoi. Speciosi: crebre caesio-puberulus ; caule sub- pedali ; corollis extus pallidis ; antherte glabrie loculis subcartilagineis basi acutis apicibus contiguis longiuscule inapertis : cvst. P. f/labri. — Utah, near Glenwood, at 5,300 feet, L. F. Ward, in Powell's Expe- dition, 1874.

MiMULUs Palmeri. Eumimulus: viscidulus sed fere glaber, spith- amajus e radice annua, paniculato-ramosus ; fuliis sessilibus integerrimis, imis spathulato-oblongis, superioribus linearibus ; pedunculis tiliformibus folium bis superantibus : calyce baud obliquo, dentibus ae(]ualibus latis obtusissimis ; corolla (^ poll, longa) move J^u nan i infundibuliformi san- guineo-purpurea calyce triplo longiore, lonis brevibus suba^qualibus. — S. E. California, on the Mohave Kiver, Palmer. A truly handsome species, well worthy of cultivation.

Okthocarpus lasiorhynciius. 0. lacero proximus ; pube moUi- ore ; floribus majoribus ; coroUie loete aurese saccis ampborilms galea tenuiter subulata dense albo-villosa superatis. — Mohave River, S. E. California, Palmer, 1876.

Munardklla Palmeri. Nana, rhizomatibus stoloniformibus per- ennans ; capitulis corollisque M. odoratisslince ; caulibus vix spithjimceis parum puberulis ; foliis coiifertis oblongo-linearibus lanceolatisve obtusissimis parvulis crassiusculis viridibus fere glabris, venis glandu- lisque punctiformibus obsoletis ; bracteis rubesceutibus ohlonjris sub- hii'sutis ciliatis ; dentibus calycis lanceolatis acutis intus marginibusque parce hispidis. — Redwood forests on Sta. Lucia Mountains, Cali- fornia, Palmer.

Stachys Rothrockii. Spithamoea, a basi ramosa, villoso-lanata ; radice ut videtur perenni ; foliis omnibus sessilibus lanceolatis obtusius- culis subintegerrimis (pollicaribus), floralibus superioribus flores baud superantibus; verticillastris sjepius trifloris spicato-confertis ; calyce sessili subcampanulato, dentibus subovatis muticis ; coroUaj (lin. 4—5 longue) tubo iucluso, galea saltern extus albo-villosa. — Zuni Village,

OF ARTS AND SCIENCES. 83

New Mexico, Dr. J. T. Rothrock, in Wheeler's Expedition, ISTk In aspect considerably unlike any other North American species : appar- ently indigenous.

Eriogonuji Greenei. Heterosepala inter E. proUferum et E. ovalifoUum : niajusculum ; foliis oblongis acutiusculis ; scapo ultra- sjjithamseo sub involucro priuiario sessili 3-radiato, radiis elongatis involucra 1-3 turbiiuita (lin. 3 longa) gerentibus quandoque pro- liferis ; perigouio albo (lin. 3 longo), segiuentis exteriuribus ovalibus basi cordulatis per costam viridulana interioribus angustioribus baud emarginatis longius adnatis. — Northern California, on rocky hills about Yreka, E. L. Greene. Au interesting accession to the Hetero- sepala section.

OxYTHECA TRiLOBATA. Cymoso-raniosa ; foliis radicalibus brac- teisque fere 0. Watsoai ; involucris longius pedunculatis pio genere maximis alte 5-partitis nunc hinc divisis, phyllis patentibus foliaceis oblongo-lanceolatis costa valida excurrente aristatis ; perigonii sepalis ligulato-oblongis superne trifidis, lobis ovato-lanceolatis erosulis acuminatis. — San Bernardino Co , S. E. California, Lenimon and Parry.

Chlor.ea Austins. Planta allia aphylla ; radicibus carnoso- fibrosis ; caulibus fusciculatis (subpedalibus) laxe vaginalis ; spica ob- longa laxiuscula ; floribus pro genere parvis albidis (perianthio parum semipollicari) ; labello trilobo, lobo medio integerrimo transverse oblongo ; anthera modo Cephalantherce substipitata. — Banks of a wooded ravine iu the Sierra Nevada, California, near Quincy, in Plumas Co., Mrs. R. M. Austin ; — whose zeal and services to botany, and notably her observations upon the habits of Darlinytonia, render it particularly proper that this remarkable plant of her own discovery should commemorate her name. I refer it to the South American genus ChlorcBa, rather than to the European and North Asian Cepha- lanthera, on account of its habit, and because there is no articulation between epichilium and hypochilium.

POSTSCRIPT.

Saxifraga chrtsantha. S. Hirculo et serpyllifoUce affinis : caudiculis perennantibus caespitor^is diapensioideo-foliatis cum stolonibus filiformibus ; foliis spathulatis seu lineari-spathulatis obtusissimis niti- dulis glabris (lin. 2-3 longis) basi sensim angustatis sessilibus, caudi- culorum crebre rosulato-imbricatis ; caulibus floriferis scapiibrmibus fere bipoUicaribus 1— 4-foliatis 1— 2-floris glabris vel superne cum

84 PROCEEDINGS OP THE AMERICAN ACADEMY

calyce reflexo glanduloso-hirsutulis ; petalis ovalibus lajte aureis basi ecallosis supra unguem truncatis vel subcordatis ; ovario et capsula late ovatis apice breviter bilobis ; seminibus oblongis striolatis nitidis. — S. Hirculus, Gray in Am. Jour. Sci. xxxiii. 409 (coll. Parry, no. 164 & 106), non L. S. serpyllifulia, Gray in Proc. Acad. Philad. 1803, 02 (coll. Hall & Harbour, no. 199), non Pursh. High alpine region of the Coloi-ado Rocky Mountains, especially abundant on Torrey's and Gray's Peaks, at 11-14,000 feet, its golden flowers close to the sward, more brilliant than those of the equally abundant Geum Rossii which accompanies it. S. Hirculus occurs at very much less elevation, fully resembling the Arctic American and the European plant. S. serpylUfolia, Pursh, now better known by good Alaskan specimens, collected by Prof. Harrington in 1871-2, is more slender, the flowers solitary and smaller, the calyx not reflexed even in fruit, petals light yellow, cells of the anther parallel, ovary partly immersed in a disk, its base adnate to the base of the calyx, the capsule dis- tinctly 2-horned at the summit, and the tijJ of the horns narrow and styliforra. These distinctions were made out several years ago, and the Rocky Mountain species has been freely distributed among bota- nists under the name of S. chrysantha, but it has accidentally escaped publication.

OF ARTS AND SCIENCES. 85

VI.

CONTRIBUTION FROM THE LABORATORY OF S. P. SHARPLES.

*

SCHWEINFURT GREEX:

SOME EXPERIMENTS ON THE ACTION OF ARSENIC TRIOX- IDE ON COPPER ACETATE, WITH THE VIEW OF INVESTI- GATING THE COMPOSITION OF THE ABOVE COiVU'OUND.

By E. R. Hills.

Read by title, November 8, 1876.

After the completion of the paper on Scheele's Green by Professor S. P. Sharpies, I became interested to know something about the com- position of the closely allied substance, Schweinfurt green, — as to whether it was perfectly definite in its composition, or whether it varied in a similar manner to Scheele's green. I therefore obtained a sample of Schweinfurt green from the Massachusetts Institute of Tech- nology, which was procured by them in the market for analysis. This was submitted to a careful analysis, and gave as follows : —

Analysis No. I.

	Per cents,
Copper oxide,	25.82
Arsenic trioxide.	45.18
Acetic anhydride (CJT,jO,.j),	15.40
Sulphuric anhydride (SO3)	1.76
Barium sulphate,	11.44 •

99. GO

If now we deduct from this the sulphuric anhydride and barium sul- phate, and calculate the percentages anew, we have, —

Per cents. Atomic Ratios. Copper oxide, 29.88 4.26

Arsenic trioxide, 52.30 3.00

Acetic anhydride, 17.82 1.98

100.

86 PROCEEDINGS OF THE AMERICAN ACADEMY

A sample of Schweinfurt green was then obtained from Messrs. Folsom & Co. of this city. This sample was said to be perfectly pure, and was made in their works. It was of a much brighter shade than the preceding, and gave on analysis : —

Analysis No. II.

	Per cents.	Atomic Ratios.
Copper oxide,	30.97	4.43
Arsenic trioxide.	52.82	3.00
Acetic anhydride,	16.03	1.79

99.82

This is very nearly the same as the preceding sample, calculated

as pure copper aceto-arsenite. It corresponds quite nearly to the

formula,

2 (CuOCJip,) 3 (CuOAs^Og),

which calculated to percentages is thus : —

Per cents. Atomic Ratios.

Copper oxide, 33.19 5.

Arsenic trioxide, 49.73 3

Acetic anhydride, 17.08 2.

100.

It will be seen by comparing the percentages that both samples analyzed contain more arsenious acid than is called for by the formula: this is most probably due to the difficulty of washing out the excess of arsenic in process of manufacture.

The foi-mula given in the books for Schweinfurt green is, —

CuOC,H,03	3(CuOAsP3),
which was based upon the following analysis : —
	Per cents.	Atomic Ratios,
Copper oxide,	31.24	3.96
Arsenic trioxide,	58.62	3.00
Acetic anhydride.	10.13	1.00

100.

This analysis was made by E. Ehrmann in the laboratory of Pro- fessor Von Liebig, and the results were published in " Der Annalen der Pharmacie," * in 1834, in which paper Ehrmann, after giving the

* Der Annalen der Pharmacie, Band XII., 1831, Seite 72.

OF ARTS AND SCIENCES. 87

origin of the salt, gives a formula for its preparation, and then the composition as determined by him.

The receipt he gives is as follows, which he states works as well in small amounts as in large : —

"10 parts verdigris are mixed with as much water at 50-55° as is necessary to produce a moderately thin emulsion : this is then passed through a fine hair sieve, to separate the marc of the grape or the small particles of copper from the basic acetate of copper.

" This emulsion is poured still warm into a solution of 8 parts of powilered arsenious acid in 100 parts water, which is kept in a state of brisk ebullition in a copper kettle. The mixing is done quickly, and meanwhile the fire must be kept bright and hot, so that the boiling of the solution of arsenious acid may not be interrupted. The color appears in a few minutes. If the verdigris is added cold, or the boiling of the arsenious acid is interrupted, the precipitate is of a dull yellow- green color, in which case some acetic acid must be added to the solu- tion, boiling a few minutes longer, and allowed to stand to cool by itself, after which the dull precipitate becomes crystalline, and is converted into Schweinfurt green.

" On account of the difficulty with which the arsenious acid dissolves in pure water, many makers add to the water, with the 8 parts of ar- senious acid, -^ parts (that is, to 8 pounds 1 oz.) of pure potash ; but, before the addition of the verdigris, the solution must be made neutral with acetic acid. . . .

" If a boiling solution of neutral acetate of copper and one of arse- nious acid in water, the amounts of each being equal, are mixed, a very voluminous precipitate of a dull olive-green color occurs immediately : if the supernatant liquid be allowed to stand in contact with this some hours, or cool slowly with it, it loses its gelatinous condition, sinks together, becomes crystalline in granular crystals, and assumes the use- ful color of Vienna green.

" The compound acquires a still more brilliant color, if an equal volume of cold water is added to the liquid after mixing.

" If the mixture, instead of standing by itself, be boiled a few min- utes, the conversion to the crystalline salt is accomplished in a very short space of time.

'' The difference in the shades of color is due mainly to the size of the crystalline grains : when rubbed to a fine powder on a color-slab, their appearance is similar. . . .

" The pure compound which was obtained by the preceding method was submitted to analytical investigation. . . .

88 PROCEEDINGS OP THE AMERICAN ACADEMY

" Sdiweinfurt green is a double salt of acetic 'acid, arsenious acid, and oxide of copper : it is entirely insoluble in water. All mineral acids, and even concentrated acetic acid, extract the oxide of copper from it, leaving the white arsenious acid bthind. It is also decom- posed by fixed alkalies, except that in this case oxide of copper remains behind. If the alkaline liquid, which has dissolved the arsenious acid, is boiled with the precipitated oxide of copper, this is reduced to the suboxide by the arsenious acid : the oxide, which is at first black, becomes orange-red by boiling. . . . Ammonia dissolves it without decompo:*ition, with the well known blue color of copper."

Some Schweiiifurt green was now prepared by the first of these receipts.

Experiment No. 1.

Took 20 grams verdigris and made it into a thin paste with water, rubbing it well in a mortar to break up any lumps and mix thor- oughly. IG grams of arsenic trioxide were dissolved in water, to which about 1 gram of potassium carbonate was added : then the emul- sion of verdigris was added to the boiling solution of arsenic trioxide, which was made acid with acetic acid. At first yellow-green copper arsenite was precipitated : this, on boiling, very gradually changed to the aceto-arsenite, at first crystallizing in a pellicle over the surface ; finally, with the addition of a little acetic acid, the whole mass became more dense and crystalline, leaving a blue solution, from which the precipitate was separated by a filter. The precipitate was washed with boiling water, till no arsenic was fo\ind in the filtrate on testing the acidulated liquid with sulphuretted hydrogen. The filtrate con- tained copper, arsenic trioxide, and potassium acetate.

The precipitate was dried at 100° C. for twenty -four hours, and then analyzed.

Analysis No. III.

	Per cents.	Atomic Ratios,
Copper oxide,	32.00	4.33
Arsenic trioxide.	55.G3	3.00
Acetic anhydride.	12.31	1.29

99.94

The precipitate was of a pale green color, inferior to the samples previously examined, and its specific gravity was much lower.

The above receipt was now varied by substituting the neutral copper acetate for verdigris : the manipulation is much easier than with the basic acetate.

OF ARTS AND SCIENCES. 89

Experiment No. 2.

80 grams arsenic trioxide dissolved in water. 100 „ copper acetate „ „ „

The copper salt was added to the solution of arsenic trioxide : as in the former case, a yellow-green flocculent precipitate was produced, which was graduMlly converted by boiling into the brilliant aceto- arsenite. The filtrate from the pigment was acid, of a deep blue color, and contained arsenic trioxide, copper, and acetates.

The precipitate wasdiied at 100° C. as before, and gave on analysis these results : —

Analysis No. IV.

	Per cents.	Atomic Ratios.
Copper oxide,	32.12	4.r>6
Arsenic trioxide.	56.08	3.00
Acetic anhydride,	10.37	1.07
H) droscopic water.	.61

99.18

These two salts approximate to Ehrmann's formula, although they vary somewliat from it. In 1858,* " N. Reilter found in four com- mercial Schweinfurt greens (No. I. was pure, II.-IV. were mixed with heavy spar and gypsum, all four samples showed the presence of free arsenious acid, they were washed before analysis), after deducting the water and impurities : —

	I.	II.	in.	rv.
Copper oxide.	33.97	34.94	33.83	33,65
Arsenic trioxide.	57.52	58.18	54.31	57.93
Acetic auhydiide,	8.51	7.88	11.86	8.42

100.00 101.00 100.00 100.00

" He says it follows from these numbers that Schweinfurt green con- sists of monarseiiite of copper, combined with vai-ying amounts of basic (not mono) copper acetate."

It will be seen, by comparison of these results with those obtained by Ehrmann, that they with one exception contain less acetic anhydride and more arsenic trioxide and copper oxide, while they do not approach the composition of the commercial samples analyzed by myself. Thia is, I think, partly due to an admixture of free arsenic trioxide.

* Jahresbericht der Cliemie, 1858, Seite 651.

90 PROCEEDINGS OP THE AMERICAN ACADEMY

Experiment No. 3.

The filtrate in Experiment No. 2 contained copper, arsenic trioxide, and acetates. To this solution, in which no precipitate occurred on the addition of more arsenic trioxide, sodium carbonate was added to faint alkaline reaction. A yellow-green precipitate fell, which was collected on a filter, washed until the filtrate was free from arsenic trioxide. Dried, the composition was, —

Analysis No. V.
Per cents.	Atomic Ratios.
Copper oxide, 50.G9	3.31
Arsenic trioxide, 38.13	1.00
Walter, 11.88

100.70

This is copper arsenite of the following formula, CugAs^O,; 2H2O, with about 4 per cent of hydroscopic water, and contained, as far as could be ascertained by careful testing, no acetic acid.

The question then arose. Does sodium arsenite precipitate pure cop- per arsenite from copper acetate in all cases, or does it also carry down some basic copper acetate with it ? This led to

Experiment No. 4.

Copper acetate, 33 grams.

Sodium carbonate, 50 „

Arsenic trioxide, 18 „

The arsenic; trioxide was dissolved in the sodium carbonate, and the solution mixed with the copper acetate solution, both being near the boiling point. A 3'ellow-green precipitate fell, the supernatant liquid contained acetates, arsenic trioxide, and carbonates, and was slightly yellow. The precipitate was separated by a filter, and washed till no arsenic trioxide was found in the wash-water. This was much like the product obtained in Experiment No. 3, except that the color was a little brighter and of a bluer shade, and when analyzed gave : —

Analysis No. VI.

	Per cents.	Atomic Ratios.
Copper oxide.	62.06	10.35
Arsenic trioxide.	37.81	3.00
Acetic anhydride,	2.70	.40
Water,	8.21	7.08

100.78

OF ARTS AND SCIENCES. 91

This shows that when sodium arsenite acts on copper acetate, if there is not a lai-ge excess of arsenic trioxide, we get copper arsenite, •which contains some basic copper acetate, as is the case with the copper sulpliate under like conditions, and tliat the acetic acid gives a brighter shade to tlie color.

To answer the question as to whether an excess of copper acetate would produce, when mixed with arsenic trioxide, a salt containiajr more basic copper acetate, we have

Experiment No. 5.

Copper acetate, 250 grams.

Arsenic trioxide, 50 „

Dissolved in water separately, and mixed the boiling solutions and boiled an hour. The precipitate was green, the filtrate from it was blue, and contained arsenic trioxide, copper, and acetates. The pre- cipitate had this composition : —

Analysis No. VII.

Per cents.

Copper oxide, 50.00

Arsenic trioxide, 35.57

Acetic anhydride, 2.47

"Water, 1 1 .07

99.11

This result, deducting hydroscopic water and calculating the per cents anew, gives : —

	Per cents.	Atomic Ratios,
Copper oxide,	52.06	10.80
Arsenic trioxide,	37 04	3.00
Acetic anhydride,	2.57	.39
Water,	8.33	7.38

100.00

This is a mixture of copper arsenite and basic copper acetate, almost of exactly the same composition as that obtained by the action of sodium arsenite on copper acetate in Experiment No. 4, and, instead of con- taining a considerable amount of copper acetate, has a very small amount.

92

PROCEEDINGS OF THE AMERICAN ACADEMY

Experiment No. 6.

To Ihe filtrate from the pigment obtained in Expt. No. 5, 50 grams of arsenic trioxide were added and some free acetic acid : a new forma- tion of the well-known color of Schweinfurt green occurred after a prolonged boiling ; this was allowed to stand over night in contact with the solution from which it was precipitated ; it was tiien tiltered off and washed free from the excess of arsenic trioxide. The filtrate was blue, and acid, containing copper, arsenic trioxide, and acetates ; on the addi- tion of more arsenic trioxide, no precipitate fell, but, on neutralizing, one was produced having the color of the one in Expt. No. 3, and it was probably of similar composition, but was in too small an amount for analysis. The composition of the pigment obtained was : —

Analysis No. VIII.

	Per cents.	Atomic Ratios,
Copper oxide.	31.00	7.09
Arsenic trioxide,	54.48	5.00
Acetic anhydride,	11.32	2.00
Combined water,	2.55	2.56
Hydroscopic water.	.65	.70

100.00 This is very near the formula, —

2(CuOCJI,03) 5(CuOAs,03)-}-2II,0, which when calculated in percentages is : —

Copper oxide. Arsenic trioxide. Acetic anhydride, Water,

Per cents.

31.12 55.43 11.43

2.02

100.00

Atomic Ratios. 7.00 5.00 2.00 2.00

This was the first hydrated copper aceto-arsenite obtained, excepting the resulting pigments from Expts. Nos. 5 and 6, whicli may be consid- ered as mixtures; for, although there was a small amount of water in nearly all samples, it was hydroscopic water, and was entirely driven oflf by heating to 105° C.

This experiment was repeated, giving : —

OP ARTS AND SCIENCES. 93

Analysis No. IX.

Copper oxide, Arsenic trioxide, Acetic anhydride, Combined water, Hydroscopic water,

Per cents.	Atomic Ratios.
31.53	7.05
55.03	5.00
10.16	1.76
2.28	2.32
.64	.60

100.04

This is a confirmation of the preceding result, and seems to prove the existence of a hydrated copper aceto-arsenite.

Having experimented on an excess of copper acetate with a small amount of arsenic trioxide, the other extreme was now tried, and, as the proportion was 5 to 1 in preceding case, so here 5 to 1 was used.

Experiment No. 7. Copper acetate, 25 grams.

Arsenic trioxide, 125 „

Dissolved separately, added the copper solution to the arsenic triox- ide, and boiled ; the reaction was as in the preceding cases ; first cop- per arsenite, changing to aceto-arsenite ; this precipitate was filtei'ed off and washed with hot water; the filtrate contained a trace of copper and a large amount of arsenic trioxide. When the excess of arsenic trioxide was waslied out of the precipitate, the latter was dried at 100° C. and analyzed.

Analysis No. X.

	Per cents.	Atomic Batios.
Copper oxide,	31.19	4.85
Arsenic trioxide.	46.47	3.00
Acetic anhydride.	14.05	1.76
Combined water,	7.05	4.85
Hydroscopic water,	1.15

99.91 This agrees with the formula, —

2(CuOC,H,03) 3(CuOAs203) +5H2O, which, calculated in percentages, gives, —

04 PROCEEDINGS OF THE AMERICAN ACADEMY

	Per cents.	Atomic Katios
Copper oxide,	30.90	5.00
Ai'seiiic trioxide,	46.22	3.00
Acetic anhydride,	15.88	2.00
Water,	7.00	5.00

100.00

This salt is in color the most brilliant of all the samples in my pos- session, and of a decidedly different shade from thei samples of the formulae, —

(CuOC,H,.0,) 3(CuOAs20,) and 2(CuOC,H,63) 3(CuOAsA),

being more grass-green, having less blue in it. It comports itself with acids and alkalies in a similar manner to the last-mentioned salt, but is a little more dense ; it holds to its five molecules of water strongly, it not being decomposed at 120° C. When heated for a long time at this temperature, it oxidizes slowly and gains steadily in weight. Tliis is probably the salt existing in the commercial samples examined minus tlie water, and is the nearest approach to them I have been able to make, the exact formula for their production being a trade secret.

"* Wagner states that the formula given by Ehrmann is only empirical, because a portion of the copper is present as the suboxide, and a portion of the arsenic as arsenic acid."

To test this statement, I examined my samples of Schweinfurt green in the following maimer: In each case a weighed amount of the green was dissolved in pure hydrochloric acid, made alkaline with ammonia water and " magnesia mixture " added, and in each case a precipitate occurred. After allowing this to stand over night, it was filtered off and washed with aqua ammonia dissolved in hydrochloric acid, and neutralized with ammonia, then acidulated with acetic acid, and acetate of uranium solution of known strength added, testing in the usual way for an excess, with ferrocyanide of potash. The first drop of uranium solution gave a brown coloration when tested with the ferrocyanide, and an excess gave no precipitate, proving beyond a doubt the absence of arsenic pentoxide.

The precipitate obtained by the " magnesia mixture " was doubtless basic magnesium sulphate and magnesia itself.

* Handbook Chemiual Technology, Rudolf Wagner, Ph. D. Translated by W. Crooks, F.R.S. Appletou & Co., N. Y., 1872. Page 58.

OF ARTS AND SCIENCES. 95

Therefore I conclude that the formulae do represent the composition, both empirically and rationally, and that there is no suboxide of cop- per present, as also no arsenic acid.

Wagner, after giving Ehrmann's receipt, publishes the following from M. Braconnot: '• 15 kilos of sulphate of copper (CuSO^-f-'^^^-.'O) are dissolved in the smallest possible quantity of boiling water, and mixed with a boiling ami concentrated solution of arsenite of soda or potash, so prepared as to contain 20 kilos of arsenious acid. There is imme- diately formed a dirty greenish-colored precipitate, which is converted into Schweinfurt green by the addition of some 15 litres concentrated wood-vinegar. This having been done, the precipitate is filtered off and washed. . . .

" It thus appears that the preparation of this pigment aims first at the least expensive preparation of neutral arsenite of copper, which is then converted into aceto-arsenite of cojjper, by digesting the precipitate with acetic acid."

Kow this is very probably the method, by which the samjile obtained from the Massachusetts Institute of Technology was made, and accounts for the basic copper sulphate found in it. The insoluble matter is used to dilute the color and as adulteration.

These latter are therefore impurities, and are to be disregarded in speaking of its composition.

Now with regard to the pure pigment: Ehrmann's analysis is with- out doubt correct, and is sustained by two samples prepared by myself; but this cannot be regarded as the universal composition of the salt, and does not, as has be^u already said, cover the commerrial samples that I found in the market. Therefore we must look farther, and we find there is another salt having the formula, —

2(CuOC,HA) 3(CuOAsA),

in two commercial samples ; hence we infer that the composition varies between these salts, that it may be CuOC^H^Og 3(CuOAs.,0.j), or 2(CuOC^Hy03) S^CuOAs^Og), or something between the two; and we also see that the amount of arsenic trioxide may vary considerably, from the difficulty with which it is removed by washing, even with hot water, in process of manufacture.

In the extract from N. Reilter, we have a series of results which vary from any obtained by Ehrmann and myself (with one exception), where the amounts of acetic acid are much less. And he states that Schweinfurt green is copper mono-arsenite combined with varying amounts of basic copper acetate. We have a variance of from

9(5 PROCEEDINGS OF THE AMERICAN ACADEMY

7.88% — 17.82% of acetic anhydride, a variance of nearly 10%. As the salt is crystalline, and is formed out of different propor- tions of the materials used, with the same composition, as it was in several cases where no great change was made, it appears as a definite chemical compound, and the variation is, I think, best explained by considering the existence of several definite salts. Also in three cases I have found water chemically combined, which shows still more vari- ance, but these salts also appear definite, and agree with vei*y simple formulas.

Pure Schweinfurt green may therefore be composed either entirely of the salt having the formula (CuOCJIuO.) 3(CuOAs03), or en- tirely of that having the formula 2(CuOC^HP3) 3(CuOAs203), or may have a composition between the two, from a mixture of these salts, and it may contain combined water having this formula, 2(CuOC,H,03), 5(CuOAs20,3)4-2H,0, or may have the formula 2(CuOC,H,03) 3(CuOAs203) 5H,0. And all tiiese results may be varied again still more by a mechanical mixture of arsenic trioxide, from the difficulty of removing the same by washing. That the arsenic is present as trioxide, it contains no arsenic pentoxide so far as I have been able to find in this investigation. The salts of the formulae 2(CuOC,H,03) 3(CuAs,03) and 2(CuOC,HA) 3(CuOAs,03)+5H20 are more brilliant than the other two with less basic copper acetate in them, the difference being quite marked.

Therefore this beautiful pigment is not so definite as has been pre- viously supposed, but may vary some ten per cent in its amount of acetic acid, twelve per cent in its arsenic trioxide, and five per cent in its amount of copper oxide ; while some samples contain chemi- cally combined water, in one specimen going up to seven per cent. And all of these would be taken by an observer for Schweinfurt green, and can only be distinguished by a slight difference in shade of color and chemical composition, which latter shows there exists three definite salts.

In the analyses of this paper, the following methods were employed:

A weighed portion was dissolved in an excess of nitric acid, the solution boiled some time in order to oxidize the arsenic trioxide, the solution was then made alkaline with caustic potasli, which pre- cipitated the copper as oxide, which if the acids are all oxidized is black; if not, orange-red, in which case the separation is not as per- fect, and it cannot be manipulated with as much ease, as when the oxidation is perfect. The fluid with the precipitate is boiled and

OF ARTS AND SCIENCES. 97

filtered, tlie precipitate washed with hot water, dissolved in dilute sulphuric acid, and the metallic copper precipitated by a battery.

The filtrate containing the arsenic is made acid with acetic acid, and titrated wilh uranium acetate solution.

This method was carefully tested against others and itself, and proved to give the most satisfactory results.

The acetic anhydride was determined by ignition with lead chromate as in an oi-ganic analysis, collecting the carbonic acid and water, and weighing the same ; the excess in weight of water above that formed from the combustion of the acetic acid, gave the total water. The hydroscopic water was determined by drying the salt for three or four hours in an air-bath at 100° — 105° C. until a constant weight was obtained, of course deducting the hydroscopic from the total water, gives that which is combined.

I owe my sincere thanks to Professor S. P. Sharpies, for his kind- ness in allowing me the use of his very convenient laboratory, his library, and for some suggestions as the investigation progressed.

Boston, October 24, 187G.

VOL. XII. (n. s. it.)

98 PROCEEDINGS OF THE AMERICAN ACADEMY

VII.

MILK ANALYSES.

By S. p. Sharples, S.B.

Presented, Nov. 8, 1876.

In my former paper on this subject, read before the Academy last Decemlxjr, I gave the residts of the analyses of a number of specimens of milk from the vicinity of Boston. Since that time 1 have iiad occasion to examine critically the method of analysis which I a^as led to adopt by my experiments, as then reported, and the results were so satisfactory that I have extended my investigations further upon the subject of pure milk as produced by cows of different breeds and by the same cow under ditfurent conditions. The pure milk for these experiments was kindly furnished me by Dr. E. L. Sturtevaut, and was in each case drawn under his own supervision.

The method of analysis followed was &'st to determine the specific gravity, by weighing 100 cc. of the milk : this was then set for cream ; 25 cc. were precipitated by acetic add and the sugar determined. Five cubic centimetres were carefully weighed, evaporated to dryness, again weighed, tlie fat dissolved out by benzine, the solids not fat weighed, and then the ash determined by ignition. The caseine was determined by difference, and of course includes all the albumen and other substances of this nature that exist in the solids not fat after the abstraction of the sugar and ash.

The test analyses, with two exceptions, were made on samples of adulterated milk, which were seized during the past year by the milk inspector of the city of Lynn.

Analysis No. I. April 1, 1876.

Cream 5^

Sp. Gr 1.020

OP ARTS AND SCIENCES.

99

	Analysis 2So. 1.	Analysis No. 2.	Average
Sugar . . .	2.86	2.86	2.860
Caseine . . .	2.99	3.00	2.995
Ash . . .	.42	.42	.420

Solids not Fat Fat . . . .

Total Solids Water . .

6.27 2.15

8.42 91.58

100.00

6.28

2.18

8.46

91.54

6.275

2.165

8.440

91.560

100.00

100.000

In each case, a sinnle precipitation of tlie caseine and fet for the purpose of determining the sugar was made ; but the solution was titrated at least twice, and the average of the results, which never varied more than a cc, taken as the amount of sugar.

This method of determining the sugar has been condemned by many chemists; but, if the precaution is taken of pi'eparing a fre-^h solution every time a series of determinations are made, the results will, so far as I have experimented, be found to be comparable with each other, and those determinations made in the same sample of milk will agree very closely with each other.

Analysis No. II. April 8, 1876.

Cream 6%

Sp. Gr 1.0215

Sugar . Caseine . Ash . .

Solids not Fat Fat . . . .

Total Solids Water . .

Analysis No. 1 3.45	Analysis No. 2. 3.45	Average. 3.450
2.78	2.79	2.785
.48	.47	.475

6.71

2.31

9.02

90.98

6.71 2.31

9.02 90.98

6.710 2.310

9.020

90.980

100.00

100.00

100.000

100 PROCEEDINGS OP THE AMERICAN ACADEMY

Analysis No. III. April 14, 1876.

Cream 4%

Sp. Gr 1.022

Analysis Analysis

No 1. No 2. Average.

Sugar .... 3.74 3.74 3.74

Caseine. . . . 3.28 3.26 3.27

Ash .56 .56 .56

Solids not Fat . 7.58 7.56 7.57

Fat 2.32 2.34 2.33

Total Solids . . 9.90 9.90 9.90

Water .... 90.10 90.10 90.10

100.00 100.00 100.00

Analysis No. IV. May 2, 1876.

Cream 5%

Sp. Gr 1.023

Analysis Analj'sis

No. 1. No. 2. Average.

Sugar .... 3.36 3.36 3.360

Caseiue . . . ' . 3.25 3.22 3.235

Ash 50 .50 .500

Solids not Fat . 7.11 7.08 7.095

Fat 2.25 2.25 2.250

Total Solids . . 9.36 9.33 9.345

Water .... 90.64 90.67 90.655

100.00 100.00 100.000

Analysis No. V.

Cream 8%

Sp. Gr 1.0255

Analysis Analysis

No.l. No. 2. Average.

Sugar .... 3.96 3.96 3.960

Caseine .... 3.64 3.69 3.665

Ash 45 .45 .450

OF ARTS AND SCIENCES. 101

Solias not Fat . 8.05 8.10 8.075

Fat ' 3.30 3.30 3.300

Total Solids . . 11.35 11.40 11.375

Water .... 88.65 88.60 88.625

100.00 100.00 100.000

Analysis No. VL August 2, 1876.'

Cream 8.5^

Sp. Gr 1.023

Analysis Analysis

No. 1. Nu 2. Average.

Sugar .... 3.04 3.04' 3.04

Caseine .... 3.62 3.66 3.64

Ash 43 .43 .43

Solids not Fat . 7.09 7.13 7.11

Fat 2.18 2.14 • 2.16

Total Solids . . 9.27 9.27 9.27

Water .... 90.73 90.73 90.73

100.00 100.00 100.00

Analysis No. VIT. August 28, 1876.

(Sample of milk known to be pure.)

Cream 5^

Sp. Gr 1.030

Analysis Analysis

Ko. 1. J{o. 2. Average.

Sugar .... 3.94 3.94 3.940

Caseine .... 4.81 4.82 4.815

Ash 65 .65 .650

Solids not Fat . 9.40 9.41 9.405

Fat 2.47 2.49 2.480

Total Solids . . 11.87 11-90 11.885

Water .... 88.13 88.10 88.115

100.00 100.00 100.000

102 PROCEEDINGS OF THE AMERICAN ACADEMY

Analysis No. VIII. August 28, 1876.

(Sample known to be pure.)

Cream 18%

Sp. Gr 1.033

Analysis Analysis

>i'o. 1. JS'o. 'A. Average.

Sugar .... 4.19 4.19 4.19

Ciuseiue .... 5.23 5.17 5.20

Ash .... . .72 .72 .72

Solids not Fat . 10.14 10.08 10.11

Fat 4.35 4.35 4.35

Total Solids . . 14.49 14.43 14.46

Water .... 85.51 85.57 85.54

100.00 100.00 100.00

These last two were samples of pure milk furnished by Dr. Sturte- vant. After finishing the first analysis of each, I was led to suspect that there must be some error in No. VII., as the total solids are low for a pure milk. I therefore repeated both analyses, taking a second sample from the bottles some five or six hours after the first samples wei'e taken, with the above results. The above eiglit are not selected analyses, but are all the duplicate analyses I have made up to this time.

These analyses, with the exception of the two last, having been made for legal purposes, it became necessary to compare the results with some standard taken arbitrarily to represent an average pure milk. The standard of 12.5 per cent total solids has been chosen by many chemists, following Mr, Wanklyn in this respect.

It is in all prohabiHty a little too low for this vicinity ; but it has been adopted for the reason tliat the courts have generally ruled that, provided a milk-dealer keeps his milk abjve the quality of the poorest milk tliat has ever been analyzed, he is to be regarded as selling pure milk, and is therefore not liable to conviction for adulteraiiou. Tlie suit for adulteration being a criminal suit and not a civil suit for damages, the defendant is given every advantage, and the public is forced to be con- tented if the milk is as rii-h in total solids as the poorest milk that a half-starved cow was ever known to give. A much more just way to the consumer and to the producer would be to give in the law a certain

OP ARTS AND SCIENCES. 103

standard below which the solids in milk should not be allowed to fall. This might be even as low as 12 per cent. This low figure would be better than the present system, because, in the first place, the consumer would get a better article than he now gets, when all milk that contains over Ut.75 per cent of solid matter has to be pa-;seJ as pure. The producer woidd fire better also, since by stopping the sale of watered milk, or rather tliat portion of watered milk tluit falls below 12 per cent of total solids, the demand would be increased for pure milk. As it is now, the majoi-ity of dealers seem to prefer to buy seven-eighths or less of the milk that they need and make up the balance with water, since water costs considerably less than milk.

It seems to be pretty generally conceded that the producer very rarely waters the milk that he delivers to the middlemen or contrac- tors. These deliver to the owuers of milk routes, who sell to private families or to stores, from whence it is delivered to the consumer. The owners of the milk routes are the ones who are generally accused of adulterating the milk.

Such a law as that mentioned would, therefore, only diminish their profits, while both tlie producer and contractor would be better satisfied , for the market would be better and the consumer would be better served. It may be urged, oii the other hand, that milk being an un- certain animal product, dependent on various circumstances for its richness and strength, — any one of which circumstances may at any time become abnormal, and so change the value of the milk, — there- fore it would be unjust to establish any fixed standard below which the solids should not fall. Tlie answer to this is that the milk of well- fed cows, in good health, rarely, if ever, falls below 11.5 per cent of total solids, and that it will average over 13 per cent of total solids, and that by establishing the standard at 12 per cent, with a margin of half a per cent for exceptional cases, no injustice is done to any one, while the public would be decidedly benefited.

The average milk containing 12.5 per cent of solids should have about the following composition : —

Actual Theory, Analysis.

Sp. Gr 1.030 1.031

Cream 8% 6%

Sugar 4.40 4.32

Caseine 4.30 4.27

Ash 60 .64

104

PROCEEDINGS OP THE AMERICAN ACADEMY

Solids not Fat .... 9.30

Fat 3.20

Total Solids 12.50

Water 87.50

100.00

9.23 3.27

12.50

87.50

100.00

For comparison I have annexed the figures as given by an actual analysis of a sample of milk which contained 12.5 per cent of total solidso

In determininj; the amount of added water for the information of the court, we may use any one of several of the determinations given; that is, we may compare the total soUds, when we have the proportion

12.5 : a :: lOO : x

a representing the amount of total solids found, and x the amount of pure milk in the sample ; or we may use the proportion

9.3 : b :: lOO : x

b represents the amount of solids not fat. A third proportion is

4.4 : c : : lOO : x

c representing the percentage of sugar as found. In order to show how nearly the amount of added water as determined by these three methods agree, I will give, in addition to the six samples of adulterated milk already given, a few more samples of milk suspected of being adulterated, and then give the amount of pure milk and the amount of added water in each sam})le as determined by each of tlie above pro- portions. I also include in the table three other samples of milk known to be pure, but which would be condemned by one or more of the above tests.

Analysis.	Sugar.	Caseine.	Ash.	Solifls not Fat.	Fat.	Total Solids.		Sp. Gr.	Cream.
No. IX.	3.52	3.37	.46	7.35	2.45	9.80	90,20	1.025	9
X.	3.58	3.25	.4.3	7.21	3.37	10.58	89.42	1 .024	9
„ XI.	3.52	3.11	.52	7.15	2.10	9.25	90.75	1 .024	6
„ XII.	3.58	3 5!)	.48	7.00	2.07	9.67	90.38	1.025	6
„ XIII.	3 78	3.40	.48	7.61	2.53	10.14	89 86	1.026	8
„ XIV.	4.88	3.48	.64	0.00	2 13	11 13	88.87	10315	10
„ XV.	4.82	3.54	.57	8.93	2.71	11.64	88.36	1028	6

OP ARTS AND SCIENCES.

105

Numbers VIL, XIV,, XV., were known to be pure milk.

	From Total Solids.	From Solids not Fat.	From Sugab.
Analysis.
	Pure Milk.	Added Water.	Pure Milk.	Added Water.	Pure Milk.	Adileil Water.
No. I.	67.52	32.48	67.47	32 53	65.00	35 00
II.	72.10	27.84	72 15	27.85	7841	21.59
„ lit.	79.20	20.80	81.89	18.61	85.00	15.00
„ IV.	74.76	25 24	76.28	23.72	70.37	23.63
V.	91.00	9.00	86.83	13 17	90 00	10.00
„ VI.	74. IG	25.84	76.45	23 55	69.09	30.91
„ vn.	95.0S	4.92	101.13	—1 13	89.55	10.45
„ i.\'.	78.40	21.60	79.03	20.97	80.00	20.00
X.	84.04	15.36	77.53	22.47	80 23	19.77
„ XI.	74.00	26.00	7t..88	23.12	80.00	20 00
„ XII.	77.36	22.64	81.72	18 28	80 23	19.77
„ XIII.	81 12	18.88	81.83	18.17	84.77	15.23
„ XIV.	89.04	10.96	96 77	3.23	110 90	—10.90
„ XV.	93.12	6.88	90.02	398	109.55	— y.55

The figures with the — sign before them sliow that this iflgredient, instead of being below the normal amount, was present in excess.

These cases, with the exception of Nos. V., VIL, XIV., and XV., were all carried into court, and convictions were secured. Xo. V. it was thought not advisable to prosecute, though there could be but little doubt of the adulteration. The other three, as before stated, were pure milk, and each one of these three rises in one determination above the standard chosen ; and, if they had been brought to me to be examined as adulterated milks, I should have refused, as I did in the case of Xo. V., to appear against the seller, as in each case there would be a strong doubt in his favor.

A paper by Dr. Mott, of Xew York, on the milk from the right and left breasts of women, suggested to me that I sliould try similar ex- periments with the different quarters of tlie udder of the cow. This I have been enabled to do throu<ih the kindness of Dr. Sturtevant.

I had previously found that I could, without any extra effort, make from four to six com|)lete analyses a day, if I had a complete set of apparatus for each analysis. Commencing work at 10 a.-\i., when the milk arrived at my office, the four analyses have been completed, ex- cept the reading of tlie volume of cream, by 6 p.m. Analyses Xos. XVI., XVII.. XVIII., and XIX., were of milk yielded by the Ayrshire cow " Model of Perfection." She was eleven years old, and calved Dec. 31, 1875. Evening's milk, Aug. 13, 1876.

106

PROCEEDINGS OF THE AMERICAN ACADEMY

The milk was drawn from each teat into a separate vessel, and was

brought to me next morning.

XVI. Right forward teat, yield 907. grams.

XVII. Left forward teat, yield 577. „

XV'^III. Right rear teat, yield 680. „

XIX. Left rear teat, vield 577. „

Total yield 2741.

	XVI.	XVII.	XVIII.	XIX.	Average.
Cream Sp. Gr Sugar Ch seine Ash	25. 1.025 4.09 4.48 .68	42. 1.024 2.18 6.58 .61	29. 1.026 3.44 5.00 .66	24. 1.028 4.20 5.59 .67	28.1 1.0257 3.72 5.11 .66
Solids not Fat . . . Fat	9.25 5 59	9.87 4.43	9.10 4.39	10.46 3.84	9.49 4.68
Total Solids . . . Water	14.84 85.16	13,80 86 20	13.49 86.51	14 30 85.70	14.17 85.83
100.00	lOO.UO	100.00	lOO.OJ	100.00

The sugar in No. XVII. was tested a second time with the same results.

Analyses Nos. XX., XXL, XXIL, XXIIL The above results varied so much that it was desirable to repeat this experiment, which v/as accordingly done with another cow, with the following results : —

Ayrshire cow " Tabitha;" feed, 4 quarts cob meal i)er day, hay. and corn fodder ; age, 2^ years; calved last spring. Evening's milk, Nov. 19, 1875. AualyzedNov. 21, 1876.

XX. Right forward teat, yield 624. grams.

XXI. Left forward teat, yield 624. „

XXIL Right rear teat, yield 680. „

XXIIL Left rear teat, yield 737. „

Total yield 2665.

OF ARTS AND SCIENCES.

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1 ; XX. i	XXI.	XXII.	XXIII.	Average.
Cream, vol. p. c. . Sp. Gr Susar Caseine .... Ash	14. 1.032 4.00 3.58 .51)	11. 1.031 5.ro 3.42 .57	13. 1.0.306 4.72 3.61 .01	10. 1.0315 4 88 3.48 .64	11.9 1.031 4.87 3.51. .60
Solids not Fat . . Fat	9 02 3.32	8 90 3.00	8.94 2.73	9.00 2.13	8.08 2.77
Total Solids . . . Water	12..34 87.66	11.90 8o.0l	11.67 88.33	11.13 88.87	1175 88.25
100.00	100.00	100.00	100.00	100.00

The variation in this case consists mainly in the amount of fat. This variation, as will be seen, amounts to 1.21 per cent. The averages for both the above milks were found by ascertaining the total weight of each product given by tlie teat, adding the four weights together and diviiiing by the total weight of milk yielded.

It is evident from these experiments that each quarter of the udder yields a milk that may differ considerably from that given by any of the other quarters. This, however, has only a scientific interest, as in practice the four quarters are drawn simultaneously and the average result is used.

Some further experiments were tried in reference to the influence of breed and feed on the quality of the milk. These are far too few in number to base any opinion on ; but, so far as I have been able to carry them, they show the need of extended experiments on this subject, — experiments which should be carried over the space of several years, with analysis at least once a week, careful records being kept of tem- perature of the air, state of the weather, and general condition of the cow ; and a sufficient number of cows of each breed should be em- ployed, that the individual equation of the cow should be eliminated so far as possible. To be comparaljle, these analyses should be either made by one person, or, if made by several, they should be made l)y the same method, and these persons should compare their working by making several simultaneous analyses of the same sample of milk.

Analysis No. XXIV., Ayrshire cow " Geor<rie ; " calved July 7, 1876; food, pasture, fodder corn, and six quarts of shorts. Evening milk, Aug. 7, 1876.

108

PROCEEDINGS OF THE AMERICAN ACADEMY

Analysis No. XXV., Ayrshire cow " Georgiana;" calved July 19 ; food the same as last. Evening milk, Aug. 7, 1876.

Analysis No. XXVI., Ayrshire cow " Georgiana ; " feed for a week previous, green fodder corn and grass. Evening milk, Aug. 19, 1876.

Analysis No. XXVII., cow " Georgiana ; " feed for the previous week, green fodder corn, grass, and three quarts corn meal per day. Evening milk, Aug. 28, 1876.

Analysis No. XXVllI., cow " Georgiana ; " feed for the previous week, grass, and five quarts of shorts, and one quart of corn meal per day. Evening milk, Sept. 3, 1876.

These two cows were full-blood Ayrshire, mother and daughter. " Georgie " was imported, and " Georgiana " was calved in this country.

	XXIV.	XXV.	XVI.	XVII.	XVIII.	Average.
Cream vol. p. c. Sp. Gr. . . . Sugar .... Caseine . . . Ash ....	14. 1.029 5.00 360 .59	17. 1.031 5.19 4.13 .07	20. 1.030 5.20 3.34 .00	5. 1.030 3.94 4.82 .65	6. 1.031 4.32 4.27 .64	12.4 1.0302 4.73 4.03 .63
Solids not Fat . Pat	9.19 3.09	9.99 . 4.20	9.14 4.34	9.41 2.48	023 3.37	9.39 3.48
Total Solids . Water. . . .	12.28 87.72	14.19 85.81	13.48 86.52	11.89 88 11	12 50 87.50	12.87 87.13
100.00	100.00	100.00	100.00	100.00	100.00

Analysis No. XXIX., Jersey cow " Ilenny ; " calved July 17, 1876 ; food, pasture and green fodder corn, two quarts mixed corn and oat meal, and one quart shorts per day. Evening milk, Aug. 6, 1876.

Analysis No. XXX., Jersey cow "Danseuse;" calved May 11; same feed as No. XXIX. Evening milk, Aug. 6, 1876.

Analysis No. XXXL, Jersey cow " Ileuny ;" feed for the previous week, corn fodder and pasture. Evening milk, Aug. 19.

Analysis No. XXXII., Jersey cow " Henny ; " food, pasture and corn meal. Evening milk, Aug. 27, 1876.

Analysis XXXIII., cow "Ilenny;" food, pasture and six quarts of shorts per day. Evening milk, Sept. 3, 1876.

OF ARTS AND SCIENCES.

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	XXIX.	XXX.	XXXI.	XXXII.	XXXIU	Average.
Cream vol. p. c. Sp.Gr. . . . Suojar .... Caseine . . . Ash ....	27. 1.027 4.20 4.42 .59	21. l.OSl 4.57 378 .69	22. 1030 5.67 2.64 .62	18. 1.033 4.19 5.17 .72	13.5 1.030 4.81 8-83 .61	20 3 1.030 4.69 3.97 .02
Solids not Fat . Fat	9 21 4.72	8.94 6.61	8.93 5.07	10.08 4.35	9.25 4.78	9 28 5.12
Total Solids . . Water ....	1401 85.99	15.55 84.45	14.00 86.00	14.43 85.57	14.03 85.97	14.40 85.60
100.00	lOU.OO	100.00	100.00	100.00	100.00

It appears from the average of these two series of analysis that in this experiment the two breeds of cows gave milk that averaged almost exactly the same composition, with the exception of the yield of flit ; the Jersey giving on the average nearly one half more fat than the Ayrshire. The average result of the thirty-four analyses of pure milk, twenty-two of which were reported kst December, and twelve now, is as follows : —

Sp. Gr 1.030

Cream vol. p. c 13.8

Sugar 4.82

Caseine 4-06

Ash 65

Solids not Fat 9.53

Fat 4.62

Total Solids 14.15

Water 85.85

100.00

"With these analyses to judge from, it seems to me that an inspector of milk is fully justified in asking a conviction from the courts, if, when the theoretical milk containing 12.5 per cent of solids is taken as a standard, each of the three proportions starting from total solids, solids not fat, and sugar, show an addition of fifteen per cent or over of water.

110

PROCEEDINGS OF THE AMERICAN ACADEMY

No specimen of pure milk that I have ever examined, or that I can find any records of, fails to the extent of fifteen per cent of indicated adulteration in all three of these particulars. And I may add still further, although the specific gravity of a milk is not regarded as a reliable indication of its purity, that, in every case of adulterated milk I have met with, the inspector was justified in his seizure, if the sp. gr. fell below 1.026.

The mistake is sometimes made of con.sidering the estimation of added water as an absolute determination, entitled to the same weight as the actual analysis. But it must be evident to any one. on a few moments' reflection, that these estimations cannot be so regarded, and that they are only approximsitions, whose chief value is to show the courts how much the milk falls below a milk of fair quality ; and, when taken in connection with the fact that pure milk never falls so far below this standard, tiiey enable the court to judge intelligently whether there are fair grounds for considering the sample to be adulterated.

Boston, Nov. 27, 1876.

APPENDIX.

It having been suggested that the first run of the milk of a cow was much poorer than the strippings. and therefore a milkman, who was desirous of proving that his milk was unwatered, might procure an analysis of such a specimen, the foIlo^^ing experiment was tried : —

Analysis No. XXXI V., cow " Georgiana," right forward teat. Even-

	Analysis No. XXXIV.	Average.
No. 1.	No. 2.	No. 3.
Sp. Gr Cream .... Sugar Ciiseine .... Asli	1.029 6%	i.o;i2 y% 4.80 4.25 .58	1.027 11% 4.50 3.! 10 .54	1.029 «% 4.61 3 65 .55
4. 3.06 .54	49 3.01 .54
Solids not Fat . . Fat	8.09 1.78	8.04 1.84	9.63 3.03	8.94 4.03	8.81 2.61
Total Solids . . Water ....	9.87 90.13	9.88 90.12	12 66 87.34	12.97 87.03	1142 88.58
100.00	IOj.uo	lOJ.UO	100.00	100.00

OF ARTS AND SCIENCES.

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ing, Dec. 3, 1876. The milk was divided into three portions, as follows . 319 grams were fir.st drawn into one bottle, 274 grams were drawn into a second, and the remainder of the milk, 100 grams, was drawn into the third bottle. These three samples of milk were brouj^ht to Boston next morning and analyzed, with the following results. No. 1 proving so poor, a second analysis was made of it. This did not change the figures to any amount.

The first drawing in this case, while showing a deficiency of total solids, and soli<Is not fat, nevertheless has rather more than the average amount of sugar, so the rule laid down would fail to condemn this as a watered milk. No one, however, would hesitate a moment in saying that it was a very poor article indeed. " Georgiana's" milk, as shown all through tliis paper, is not a very rich milk.

The near approach of Ayrshire milk to woman's milk is worthy of remark. The average of many analyses of woman's milk, as given by different authors, is as follows : —

	Colnrert Woman's Milk Average of 12 Analyses, by Mott.	Wliite Woman's Milk Average of 89 Analyses, by Verniiis and Becquerel.	Wliite Woman's Milk Average of 14 Analyses, by Sijiiou.	White Woman's Milk Average of 14 Analyses, by Tidy.
Sugar Caseine Ash	5.71 332 .60	4 364 3.924 0.138	4 82 3.43 0.23	4 265 3.5-23 0.285
Solids not Fat . . Fat	9.63 4.03	8.426 2.666	9.11 2 53	8.073 4.021
Total Solids . . . Water	13.66 8634	11 092 88.908	11.64 88.36	12.194 87 806
100.00	100.00	100.00	100.00

These differ fully as much among themselves as any one differs from the average of Ayrshire milk, as given. Any tampering with Ayrshire milk, such as adding sugar and water to it, in order to make it more nearly resemble woman's milk, will therefore evidently do more harm than good: it is free from the excess of fat which often- times renders Alderney milk unfit for food for delicate children, and I have been assured by those who have used it that it makes an excellent substitute for woman's milk. For children's food, it evidently needs

112 PEOCEEDINGS OF THE AMERICAN ACADEMY

nothing done to it, except warming it slightly, so as to take the chill off.

In this connection, I think I am justified in saying that no one cow's milk. is as uniform in composition as the milk of a herd of cows, and that, if a uniform diet is wished for a child, it will be much better secured by mixing the milk of a number of cows, than when it is attempted by trying to secure the milk of a single cow. Since, as we see, the milk of any one of the cows taken varies very considerably.

Boston, Dec. 7, 1876.

OF ARTS AND SCIENCES. 113

VIII.

ON A NEW MODE OF MANIPULATING HYDRIC

SULPHIDE.

By Josiah p. Cooke, Jr.,

Erving Prqfessor qf Chemistry and Mineralogy in Harvard College. Presented May 30th, 1876.

In chemical laboratories, where instruction in qualitative analysis is given to large numbers on the class system, the use of hydric sulphide gas as a reagent is attended with grave inconveniences. These evils can in great measure be avoided by substituting for the gas a solution of the reagent in water, saturated at the ordinary temperature and pressure of the air ; when, as is well known, one volume of water dissolves about 3.4 volumes of the gas (measured at 15° C. and 76 cm.). Such a solution was for a long time used in the laboratory of Harvard College. It was prepared in a long series of two litre bottles connected by glass tubes in the usual way, and the solution was kept in the laboratory in a large tubulated glass flask, from which it was drawn by the students, as occasion required. This solution answers almost every purpose for which the reagent is used in the ordinary course of qualitative analysis, and the few conditions under which it does not give satisfactory results can be easily avoided. Moreover, in ease of application and promptness of effect it has all the advantages of a liquid reagent ; and the only inconvenience its use involves is an occasional evaporation of a solution, which the dilution by the reagent may render necessary. Of course a solution of hydric sulphide is liable to oxidation, and soon becomes turbid in contact with the air ; but this change can be easily avoided by fitting to the neck of the flask (in which the solution is kept), by means of a rubber stopper, a glass tube dipping under the liquid, and connecting this tube with one of the vents of illuminating gas in the laboratory.

For quantitative work, and for the preparation of chemical products, when considerable quantities of metallic sulphides must be precipitated, a solution of hydric sulphide, saturated under the ordinary pressure of

VOL. XII. (N. S. IV.) 8

114 PROCEEDINGS OP THE AMERICAN ACADEMY

the air, is inconveniently dilute ; and two years since we described a simple method by which a solution concentrated under pressure could easily be prepared with the ordinary laboratory appliances. A heavy glass bottle of about four litres' capacity served as a generator, and from this the gas passed through a wash-bottle into two other bottles of the same size and strength as the first. The intermediate bottle was three-fourths filled with water, while the last served simply as a gasholder. The connections were so arranged that the gas, after bubbling up through the water, was delivered at the top of the gas- holder ; and, by a tube uniting the bottom of the gasholder with the water-pipes of the laboratory, the interior of the apparatus could be submitted to the pressure of a column of water sixty feet high. The gasholder was also provided with an exit tube, which could be closed by a compression cock. The connecting tubes all passed through rubber stoppers which were firmly wired to the necks of the bottles, and the water-bottle was connected with its neighbors by two lengths of stout rubber hose so that the water could be shaken up with the gas without disturbing the rest of the apparatus. In order to saturate the water with hydric sulphide, a charge of ferrous sulphide sulphuric acid and water sufficient to yield at least three times the amount of gas theoretically required was placed in the generator, and, after the connections were made, the gas was allowed to stream through the ap- paratus until all the air was displaced. The exit tube of the last bottle was then closed, the water pressure turned on and the water-bottle frequently shaken, until absorption ceased, and the aqueduct water — at first forced by its pressure into the gasholder — was driven back into the pipes. Before dismounting the api^aratus, the rubber connec- tors were all closed by compression cocks, and care was taken to vent the generator gradually. Moreover, the connectors of the water-bottle were so arranged that when the apparatus was dismounted a short piece of rubber hose was left attached to each orifice of the bottle, both of which were closed by compression cocks. To one of these a vent tube was subsequently attached, and by this the solution was drawn off at pleasure, as from a soda-water siphon.

This simple apparatus was constantly used by us for two years, and served an excellent purpose ; but it was found that after the glass genei'ators had been charged several times they were liable to burst under the same pressure which at first they had readily sustained. The same accident never happened to the other bottles. But of course, if the pressure is long continued, bottles of glass of the size named, however well made, would be liable to such an accident ; and, if the

OP ARTS AND SCIENCES.

115

apparatus is to be remounted, it would be better to use a metallic vessel for the generator, aud to cover the glass bottles with some kind of netting. The experience with the glass apparatus led us to seek to adapt to the same purpose some one of the various soda-water appara- tuses which are greatly used in the United States for the production of effervescing drinks. After examining several of the patterns in the market, we selected for trial the one represented below, which is man- ufactured by the firm of John Matthews, of New York, at their estab- lishment, — First Avenue, 26th and 27th Streets, — in that city. The apparatus was designed by them for preparing that overcharged aqueous solution of carbonic dioxide, which in the United States is familiarly called soda-water ; but with a very slight modification it can be used with equal efficiency for the preparation of a similar solution of hydric sulphide. We have worked out the details of the process, which this new application involves, and publish them with the hope that the apparatus may be found of as great value in other laboratories

Fig. 1.

116

PROCEEDINGS OF THE AMERICAN ACADEMY

as in our own. The wood-cuts are taken from the catalogue of the firm, who have kindly loaned the blocks for this paper ; and we would here express our obligations to them for their great courtesy and lib- erality during the whole course of our exjieriments.

The apparatus consists of two parts, the generator and the fountains ; and in Fig. 1 the generator is represented connected by a rubber hose with one of the fountains, of which in practice we use three, connected in a line by similar lengths of rubber hose, like so many Woolf's bot- tles. In the figure, only the first of the line is represented, which is set on trunnions in a frame, in order to facilitate the agitation of the water and the gas. Only one of these frames, however, is required, to which the other fountains can readily be transferred. A section of the generator is represented in Fig. 2. It is made of cast iron, and in

Fig. 2.

two parts (readily distinguished in the figure), which are firmly bolted together, so as to confine in its place the bell-metal jjlate M, which separates the upper from the lower chamber. In the lower chamber is placed dilute sulphuric acid, which is poured in through the bung A.

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117

In the upper chamber, and resting on the plate, is placed coarsely powdered sulphide of iron, which is put in through the bung B. Through the plate M, and on two lines at right angles to each other, there are cut radial slits, ^ an inch wide, which are guarded by four iron arms. These arms are attached to the agitator shaft S, and move over the surface of the plate, alternately covering and uncovering the slits, when the handle E is turned. To the lower end of the same shaft is fastened the agitator O, which is turned simultaneously with the arms just mentioned. After the apparatus has been charged, it is evident that by turning the handle the sulphide of iron may be sifted down at pleasure into the acid water below ; and the handles and arms are so disposed that when the bungs are uncovered by the handles the slits are covered by the arms. From the generator, the gas passes through the washer R, whose relations to the apparatus, as well as that of the pressure gauge, are evident from the figure. The generator is lined with lead, and the rest of the apparatus, including the bell-metal plate M, with pure tin. The lead lining of the generator is seamless and very heavy, and all the cocks are lined with block tin tubing. Of the various valves, bungs, and stuffing boxes indicated in the figure, it is unnecessary to speak in detail. It is sufficient to say that they are of excellent workmanship, and during a year's trial have kejit perfectly tight. The charging bung, B, however, is closed by a safety cap of peculiar construction, which deserves special mention, because it insures the safety of the apparatus. The cap is represented by Fig. 3, and a section is given in Fig. 4. It will be seen by the last that the escape of the compressed gas from the generator through the apertures d is only prevented by a thin disk a, which is shown in detail by Fig. 5.

Fig. 3.

Fig. 5.

FifT. 4.

This disk is made of two thin plates : the lower one, which comes in contact with the acid spray, is of lead, and the upper one of silvered copper, whose thickness is so adjusted that it must be at once ruptured if the pressure in the apparatus should become unduly great.

118

PROCEEDINGS OF THE AMERICAN ACADEMY

Although the so-called soda-water fountains — in which the solution of the gas and water is made — have all in general the same simjDle relation of parts, they are constructed of very different materials and after very different methods. The outside shell may be either of ham- mered copper or of some form of iron, and this may be lined with tin, enamel, or glass. After having determined by experiment that a solu- tion of hydric sulphide — especially when some carbonic dioxide is added — exerts no action on a surface of metallic tin, except a very slight and superficial staining, we selected as best adapted to our purpose the steel fountains, also manufactured by the firm of John Matthews, Fig. 6. These are made of plates of steel, united in a

K.VkKi.'i^^^^'^^^

Fig. G.

peculiar way invented by themselves so as to secure with comparative lightness very great strength. They are lined on the inside with sheet tin, and the tin lining forms an independent vessel, which alone is connected with the bungs. The tubes and valve cocks are also either made or lined with tin, so that the solution never comes in contact with any other metal. For making ordinary soda-water, the fountain requires only a single valve, which connects with a tube leading to the bottom of the vessel, and this serves both to charge the fountain and to draw

OF ARTS AND SCIENCES. 119

off the solution when made. But since a solution of hydric sulphide is rendered turbid if left in contact with eveu a small quantity of air, and since a variable amount of free hydrogen is always formed by the action of sulphuric acid on common sulphide of iron, it was necessary for our purpose to add to the ordinary fountain a vent cock as shown in the last figure. This enables us to connect together several foun- tains after the manner of Woolf's bottles as already described, and, by passing the current of gas through the whole line, to drive out all the air originally in the apparatus, as well as the free hydrogen subse- quently evolved. Moreover, in the preparation of the solution of hydric sulphide, the generator should be much larger relatively to the fountains than in the preparation of soda-water. Thus we use for charging the so-called six-gallon steel fountains, the "Upright Generator " known as No. 40, which has a capacity below the diaphragm of sixty litres. It should be here stated that the fountains are only rated at two thirds of their total capacity, which is the volume of soda water which is ordinarily made in them. They should never be more than thi-ee-fourths filled with water. But, even with this liberal allowance for gas room, the six-gallon fountains referred to will hold twenty-five litres of water. It may also be stated, although the fact must be evident, that a single large fountain will not give as good results as several small ones of equal capacity ; since in expelling the air and free hydrogen, as we have described, there would be a consid- erable loss of material, if only one fountain were used. Still, in labora- tories where the consumption is not great, the loss is not important ; and the smallest " Upright Generator," with one six- gallon fountain, will be found to be a perfectly satisfactory apparatus.

Assuming first that the larger apparatus is used, the method of charging is as follows : The large generator is too heavy to be readily moved, and should be placed so that the discharge valve will empty directly into a drain. Water also should be brought to the apparatus by hose, — if possible, both hot and cold water, — not only for convenience in charging, but also in washing. Finally, there ought to be a good flue in the neighborhood, into which the waste gas may be discharged. The apparatus having been thus established, the three fountains — first rinsed out — are filled each with twenty-five litres of distilled water, and, the valves having been secured, the fountains are connected with each other and the generator by means of stout rubber hose as already indicated, and the vent valve of the last fountain is connected with the flue by a length of common gas hose. The generator is then charged as follows : The handle is first placed so as to uncover the bungs and cover the slits in the diaphragm. Through the bung A is

120 PEOCEEDINGS OP THE AMERICAN ACADEMY

now poured 40 litres of hot water, heated to between 70° and 80° C, and then 5 litres of common oil of vitriol are poured very cautiously into the same bung through a lead funnel with narrow spout provided for the purpose. The acid water will thus be heated nearly to the boiling point, and its capacity of dissolving ferrous sulphate raised to the maximum. Next 6 kilogrammes of sulphide of iron — previously sufficiently pulverized to pass through a wire sieve with eight meshes to the inch, and mixed with two kilogrammes of marble powder — is run through a wide-mouth funnel into the bung B. The bungs having been now all closed, the joints of the apparatus tested, the exit valve D of the generator and all the valves of the fountains opened, a small amount of the powder is sifted down into the acid water by turning the handle not more than a single revolution, always taking care to leave it so that the slits of the diaphragm shall be left covered. The gas is then allowed to stream through the apparatus, and tested as it escapes into the flue, until it burns without explosion, using a small pneumatic trough for that purpose. The air is now nearly expelled, and the escape of gas should be reduced by the last vent valve until the current only su^jplies a small jet, which may now be attached and lighted with safety, and by the size of this flame the vent may after- wards be regulated. The handles are now slowly turned, and the pressure in the apparatus carried up to about 120 pounds. The valves of the fountains and the valve D of the generator are now all closed, and the two last fountains detached, leaving the first (which is mounted on a frame as represented in Fig. 1) united to the generator as before. This is now rocked for several minutes to and fro, in order to thoroughly agitate the water with the gas. The stop valve G should then be opened, and then the valve D (very gradually), so that the gas may be admitted slowly to the fountain. The valves are then again closed, and the agitation renewed, and the same operation is repeated several times until no more gas is absorbed by the water in the foun- tain, the pressure in the generator meanwhile being maintained at 120 lbs., by turning the handle. The first fountain is then removed, and the same process repeated with each of the others. At the close of the operation, after all chemical action has ceased, there remains in the generator — both free and dissolved in the liquid residue — a large volume of hydric sulphide gas. This we economize by venting the generator slowly through Woolfs bottles containing aqua ammonia, and thus preparing at tlie same time ammonic sulphide. It is not unimportant to aild that the generator should be emptied before it cools, and the ferrous sulphate has time to crystallize. The discharge valve R should then be removed, and the whole apparatus thoroughly

OF ARTS AND SCIENCES. 121

washed out. If the valve becomes clogged, it can generally be cleared by developing pressure in the generator by means of a small charge of ground marble. Otherwise, after the pressure has been relieved, and the upper valves and bungs closed, the discharge valve must be cautiously removed, and an opening forced through the lower bung. Such details are necessary in order that others may profit by our ex- perience ; but, lest the details should convey the impression that the apparatus is complicated, and that the process requires skilled labor, it may be stated that in this laboratory the apparatus is entirely iu charge of a laboratory servant, and may be managed by any workman of ordinary intelligence. It does not require more than four hours to work over a single charge, and this yields 75 litres of hydric sulphide solution under a pressure of 120 lbs. According to our experience, this supply lasts with a class of one hundred students in qualitative analysis about a month. For laboratories where the classes are much smaller than this, we should recommend the smallest size generator, which may be used with a single six-gallon fountain. The smaller apparatus is managed in precisely the same way as the larger, only taking one half the quantity of materials. It is important as before to wash out in the first place all the air, and to maintain a small cur- rent of gas through the vent valve of the fountain while the pressure in the apparatus is rising. This of course entails some loss of hydric sulphide ; but the chief loss is caused by the venting of the generator, and all this gas may be utilized for the preparation of alkaline sul- phides as described above, or this waste gas may be used for washing out the air from a second fountain, and thus preparing it for a subse- quent charge.

For dispensing the reagent in our qualitative laboratory, we place the fountain iu a cupboard and connect it by a block-tin tube with a so called "draught column," Fig. 7, in the ventilating hood above. From this each student draws the reagent as it is required. In quan- titative work we may draw the charged water directly from the fountain into the midst of the solution to be treated, using simply a common rubber hose terminated by a glass tube which dips under the surface of the liquid : the hose is attached to the nipple of a cajj which screws on to the valve of the fountain, and by confining two or more disks of linen cloth between the cap and the head of the valve (like washers) we can filter the solution as it flows out. It is more con- venient, however, to distribute the reagent to advanced students in the well-known soda-water siphon, Fig. 8. These require no description, but as the simple apparatus used for filling the siphon is not yet a familiar object in chemical laboratories, we give a figure of the

122

PRaCEZDLN'GS OF THE AMERICAN ACADEMY .

apparatus (Fig. 9), taken, like our other cuts, from the catalogue of John Matthews. By pressing the foot on a pedal shown at the base

Fio-. 7.

Fis. «■

of the apparatus, the siphon — confined in a cage — is raised, so that its mouth is forced tightly against one opening of a valve of peculiar construction, the second opening of which is united by a block-tin tube to a fountain ; while at the same time the handle of the siphon is pressed back. On now pushing the upper lever shown in the cut to the right, the valve of the fountain having been previously opened, a con- nection is made between the fountain and the siphon ; when the charged water rushes into the latter, condensing the air to a fraction of its origi- Bal volume. If next the same lever is pushed momentarily to the left, the first connection is closed; while a vent is opened, through which the condensed air rushes out into the atmosphere before the gas in solution has time to escape, and then on pushing back the handle a further portion of liquid enters, nearly filling the interior of the bottle. Lastly, on raising the foot, the valve of the siphon shuts at the same time that the bottle is lowered and released from its cage, — the whole process being the work of a few seconds. At the first filling, there sometimes remains a small amount of air in the siphon, so that the solution becomes slightly turbid on standing; but this effect of oxidation can be easily avoided by using a sufficient amount of marble powder

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123

iu charging the generator. This siphon unquestionably affords the

most convenient mode of using hydric sulphide; and for a private

laboratory a single siphon, well charged,

will afford as ample a supply as will

ordinarily be needed. It is greatly to be

hoped that our manufacturing chemists

may soon find an advantage in supplying

this important reagent in such an elegant

form.*

When the water is charged as directed above, it of course holds in solution, be- sides hydric sulphide, a considerable vol- ume of carbonic dioxide ; and if, under any circumstance, the presence of this last gas would produce an injurious effect, the marble powder can be simply omitted in charging the generator. In almost all cases, however, the carbonic dioxide ex- erts a very beneficial influence, and in several ways. In the first place, it in- sures the non-action of the hydric sul- phide on the metallic surfaces of the ap- paratus. In the second place, it protects the solution from the action of the air when it is drawn into an open vessel, so that after a metallic sulphide has been precipitated by an excess of the reagent, the products may be digested in an open flask or beaker without fear of oxidation. In the third place, the carbonic dioxide adds greatly to the tension of the confined gas, and enables us to develop sufiicient pressure to charge the siphon without unnecessarily increasing the strength of the solution of hydric sulphide.

Chemical Laboratort of Harvard College, 1876.

Fig. 9.

* All the apparatus here described may be obtained from the firm of John Matthews, First Avenue, 26th and 27th Streets, New York, at very reasonable rates. Be careful in ordering to state the use to which the apparatus is to be put, with the caution that no silver plating or lead paint should be used upou it.

124 PROCEEDINGS OF THE AMERICAN ACADEMY

IX.

ON THE PROCESS OF REVERSE FILTERING AND ITS APPLICATION TO LARGE MASSES OF MATERIAL.

By Josiah p. Cooke, Jr.,

Erving Professor of Chemistry and Mineralogy in Harvard College.

Presented May 30, 1876.

Bt reverse filtering is meant a process of filtration in which the liquid to be filtered is drawn upwards instead of flowing downwards in the usual way. Such a system is often used in the arts, as when a porous septum is attached to the mouth of a suction pipe ; or as in the small portable filters so useful to travellers, by which clear water may be sucked up from a muddy pool or turbid stream. These last suggested the application of the same principle in chemical analysis to the treat- ment of those precipitates which are usually weighed on a dried filter. In such cases, it is of course essential that the weight of the paper disk used as a filter should remain invariable ; and this constancy can be best secured by making the disk as small as possible. If the filter is large, it is impossible to have any confident assurance of the constancy of its weight, however great the care that may be taken to secure a similarity of hygrometric conditions at the two weighings ; and hence it has not hitherto been practicable to determine on a dried filter the weight of any considerable quantity of a precipitate with accuracy. But, in the process of reverse filtering, we can both wash and collect very large masses of precipitates with a filter not more than an inch iu diameter ; and if, before drying, these little disks of paper are soaked in dilute hydrochloric acid, and afterwards thoroughly washed in water, their weight remains practically invariable. Indeed, it is not necessary to enclose the filter in a weighing tube, or to pay any special regard to its hygrometric conditions other than to keep the usual drying materials in the balance case. The only liability to alteration of weight would arise from the dissolving of soluble material in the paper, and this may be wholly prevented by previously washing the disks as just described. In the early part of 1873, having occasion to determine large quan-

OF ARTS AND SCIENCES. 125

titles of sulphide of antimony, we in the first j^lace employed the porous filtering cones described by Prof. C. E. Munroe ; * but we found these both too limited in capacity, and too susceptible to hygroscopic influ- ences, to give the degree of accuracy we required. We were therefore led to devise the following apparatus, which Figures 1 and 2 will help us to describe. The most essential part of this appa- ratus is the platinum " rose " represented by Fig. I. This is cemented bv sealinor-wax to the end of a glass tube, and to its perforated base the small filters are applied. The glass tube is so cemented Fig. 1.

into the neck of the " rose " that the end may reach quite down to the perforated plate, and thus draw up all the liquid which collects in the hemispherical cup. Moreover, the perforated plate has an unbroken rim about -jV ^^ ^^ '^^^^ wide around the edge, which is sufficient to prevent any solid particles from creeping by the edges of the paper disk. The success and rapidity of the filtering depend on the proper construction of the perforated disk, and we obtained the best results only after several trials. The holes should be smoothly perforated about 5^0 of an inch in diameter, and as numerous as possible, leaving the unbroken rim described above. After the perforations are made, the face of the plate should be ground perfectly smooth. We use two sizes of these " roses," in one of which the hemisphere is \^ of an inch, and of the other li inches in diameter; but the smaller is the more useful, and is sufficiently large for all ordinary purposes. A disk of washed Swedish filtering paper, || of an inch in diameter, weighs only about 20 milligrammes ; and, to give an idea of the rapidity of the filtration, it is sufficient to say that, under a pressure of 50 centi- metres of mercury, these filters will pass from 20 to 30 litres of clear water in an hour. We have been greatly indebted to Messrs. John- eon, Matthey, & Co., of Hatton Garden, London, for the care they have taken in the construction of these " roses ; " and they can be procured of them through the mail. The cost of the smaller size is fifteen shillings sterling. The construction of the rest of the apparatus is made clear by Fig. 2. One of the stems of a glass three-way tube is clamped to an arm which can be raised or lowered on the vertical bar of an elevating stand by a rack and pinion movement, which ought, however, to be so loose, that the arm can be pushed suddenly up when necessary. By its second stem, the three-way tube is connected

* American Journal of Science, May, 1871.

126

PROCEEDINGS OF THE AMERICAN ACADEMY

by a rubber hose with a large glass bottle, in which a partial vacuum is maintained by a Buusen pump, but this connection can be closed by

Fig. 2.

a compression cock. The third stem, which makes a connection with the atmosphere, is closed by a rubber connector and nipper tap, and serves to suddenly relieve the pressure in case the filter slips or breaks. From the first and vertical stem of the three-way tube below the clamp is suspended the glass tube, having the rose at its end. The suspension consists of a rubber connector, so long that it can be bent double and the rose inverted, and so stout that when thus bent the connection with the bottle is completely closed. When inverted, the tube of the rose rests against the thumbscrew of the pinion, and is thus confined.

In order that we may make clear the mode of using the apparatus, let us assume that five grammes of antimonious sulphide have been precipitated in a glass beaker, holding two litres of liquid, and that the precipitate has settled, — as it will after boihog, — leaving the super- natant liquid perfectly clear. A partial vacuum having been formed

OF ARTS AND SCIENCES. ItiJ

in the bottle, and the beaker having been placed on the stand, we begin by attaching the paper disk to the base of the rose, moistening it for the pnrpose with water, and forcing it with the thumb against the perforated plate until the adhesion is complete at every point. It is important that the disk should not overlap the edge of the plate ; and, if the plate has been made as described, it will adhere tightly without so doing. The compression cock is then slowly opened ; and, as soon as the sound indicates that the air is being sucked through the filter, the base of the rose is quickly sunk under the liquid, and constantly lowered by the rack and pinion movement, as fast as the liquid is drawn off. The supernatant liquid may thus be decanted until the rose is close down to the precipitate ; but care should be taken at this stage not to push the process too far, lest the filter should become clogged by the adhesion of solid particles, as would be the case, if it comes too near the level of the precipitate. When the safe level has been reached, the arm of the stand is suddenly pushed upwards, while the rose is inverted and supported as above described. The beaker is now filled up with hot water ; and, after the precipitate has subsided, the wash water is drawn off as before, and so repeatedly as often as may be necessary. It is important, however, to carefully watch the filter, and every time before immersing the rose to see that the paper is moist and firmly adhering to the perforated plate. It is further essen- tial that the suction should not be for a moment interrupted while the filter is immersed. This condition is secured by the simple rubber joint we have described ; for, while when the rose is inverted the con- nection with the bottle is closed, the moment it is turned down the connection is opened, and the filter begins to draw. If, however, by any accident the filter should slip, the operator when on his guard can avoid loss of material by quickly opening the nipper tap, and relieving the pressure until the rose can be withdrawn and washed out. The filter can then be fished out with a glass I'od, washed off and replaced. A good strong filter will bear quite rough treatment ; and, if in the pro- cess it becomes clogged, it can be taken off when the rose is inverted, and the adhering precipitate washed back into the beaker. When re- placed, the paper thus cleansed often filters as rapidly as before. If, as is sometimes the case, the paper becomes hopelessly clogged, no great loss of accuracy is suffered by using a second or even a third filter. Of course, they must all be dried, and weighed either with the precipi- tate or apart, as most convenient.

The precipitate, having been thus washed, is next to be transferred to the crucible in which it is to be weighed ; and, to hold five grammes

128 PROCEEDINGS OF THE AMERICAN ACADEMY

of precipitated antimonious sulphide, we shall require a crucible hav- ing a capacity of 250 cubic centimetres. As much of the water as can readily be decanted from the precipitate is first poured into the cru- cible and drawn off with the filter, and then the precipitate is washed in with as little additional water as possible. Now the filter is plunged into the semi-fluid mass, and must not afterwards be removed until the process is completed. The rose ought not even to be raised however slightly, although additional material may be poured in around it. As the mass contracts in the crucible, the filter must be made to follow, always keeping it immersed ; and during this time the precipitate which has collected around the j^latiuum rose may be washed down by a stream from a wash bottle. In this way the greater part of the water can be removed, leaving the precipitate nearly as compact as it is left on a common filter, when dried by Bunsen's pump. When the precipitate is in this condition, the pressure is relieved by opening the nipper tap, and the rose raised, which leaves the filter behind. If any of the precipitate has clung to the platinum, this must now be washed into the crucible with a few drops of water, the rose and tube having first been detached from the connector for the purpose. It only now remains to dry the precipitate with the •little filter, and weigh it. If it is important to dry the precipitate at a temperature above 150° C, or even to ignite it, the mass should first be thoroughly dried at 100°. The little disk of paper can then be removed and weighed sei^arately, while the rest of the mass is heated to a higher temperature. The amount of material which remains adhering to the paper under these circumstances is exceed- ingly small, not usually exceeding a few milligrammes ; and allowance can be made for it in the final result, without sensible error.

Like other analytical processes, this method has its limits ; and any attempt to extend it beyond the sphere of its usefulness will lead to unsatisfactory results. It is of no use for filtering turbid liquids, since the small filters are rapidly clogged, and the process becomes propor- tionally slow. Whenever, however, a precipitate settles clearly, this method enables us to wash, collect, and weigh very large quantities of precipitates in a very short time with wonderful accuracy. We have used it chiefly to determine sulphide of antimony and chloride bromide or iodide of silver ; and the results of the following analyses, extracted from our forthcoming paper on the Atomic Weights of Antimony, will show how great accuracy can be attained with it : —

OF ARTS AND SCIENXES. 129

Synthesis of Sulphide of Axtimo.vy.

Weiglit in Grammes of Sb taken.	Weight of Sb„ dried at ISO'	S3 u.	Per cent of S ill same.
2.1439	3.0025		28.58
2.3417	3.2792		28.59
2.2182	3.1061		28.59

Analysis of Antimoniods Chloride.

Weight in Grammes "Weight of AgCl Per cent

of Sb CI3 taken. obtained. of Chloiine

20300 3.8282 4G.652

1.3686 2.5813 46.659

1.8638 3.5146 46.651

Analysis of Antimonious Bromide.

Weight in Grammes of Sb Bi^ takun.	Wei.'htof Ag obtauied.	Br	Per cent of Brouiine.
1.2124	1.8991		66.655
0.9417	1.4749		66.647

These analyses exhibit a fair sample of the results which can easily be obtained with this method. In order to assure ourselves that the weiglit of the small paper disks remained constant, we have repeat- edly dissolved off the small amount of adhering precijiitate, and after washing and drying reweiglied the disks at the completion of the analysis. Even with the larger di?ks there was in no case any mate- rial change in the weight, and in most aises no alteration whatever could be detected with a balance turning readily with -j^ of a milli- gramme.

The method of collecting precipitates here described, which, as we have shown, is so useful where considerable quantities are to be esti- mated, is equally applicable to very small amounts. When the quan- tity of the precipitate does not exceed a few milligrammes, the whole becomes fiistened by the suction to the surface of the paper. There is then, of course, no need of a crucible in the process. The filter, hav- ing been dried in a watch glass, is weighed by itself, and a result of very great accuracy is reached with great i-apidity. AVe have in this way fre- quently estimated minute quantities of baric sulphate and argentic chlo- ride, whose weight proved to be only a fraction of a milligramme.

VOL. XII. (n. S. IV.) 9

130 PROCEEDINGS OF THE AMERICAN ACADEMY

Although the apparatus here described and figured was invented independently by myself in order to overcome difficulties, already stated, which I met with in the course of my investigations, yet in its main features I was anticipated by Professor H. Carmichael,now of Bow- doin College ; and I had the misfortune not to have my attention called to his paper on the subject — dated at Gottingen, 1870, and published in the Zeitsclirift fur Chemie, neue Folge, Band VI., 481 — until long after my own apparatus had been perfected. But although Professor Carmichael and myself started from the same fundamental idea, yet we have worked this idea out in very different forms, and with very differ- ent purposes in view. While therefore I would acknowledge most fully Professor Carmichael's priority, I have thought it best to publish this paper with the sole object of adding to his previous work the results of my own experience, and with the hope that I may thus aid in introducing into analytical laboratories what I believe to be the most important improvement in analytical chemistry which has been made since the invention of the Bunsen pump.

Chemical Laboratory of Harvard College, 1876.

OF ARTS AND SCIENCES. 131

X.

coxTRiBUTioxs feo:m physical laboratory of har- vard COLLEGE.

No. XIi: — ON VORTEX RINGS IN LIQUIDS. By Joiix Trowbridge.

Presented, March 14, 1877.

It has often been observed by chemists that a drop of colored liquid falling from a burette into a liquid of a different specific gravity, in which it can diffuse, assumes tlie form of a ring. Vortex motion, by the researches of Helmholtz, Thomson, Rankine, and Maxwell, is now attracting so much attention, that I have thought that a study of the general equations of motion of matter in connection with a study of these rings would contribute to our knowledge of vortex movement.

Prof. W. B. Rogers publislunl in " The American Journal of Arts and Sciences," Vol. XXVI., 1858, a paper on smoke rings and liquid rings, and described several methods of studying them. In Professor Tait's " Recent Advances in Physical Science," a method of forming smoke rings is given. The apparatus consists merely of a large box closed at one end by a thin sheet of India rubber, or with a tightly stretched towel, and having a circular opening of six or eight inches in diameter at the other. Clouds of sal-ammoniac vapor are generated inside the box, and rings are expelled from the circular opening by a blow upon the rubber or towel. Sir William Thomson suggests that two such boxes placed so that the rings may impinge on each other at any angle would form a useful apparatus for studying the behavior of such rings towards each other. At the conclusion of this paper, several metiiods of studying liquid rings will be described. When a drop of liquid falls from a short distance into a liquid of less density, in which it cannot diffuse, the conditions of its motion just after the instant of its striking the surface of the liquid of less density are indicated by the general equations of heterogeneous strains.* " For

* Thomson and Tait's ivatural Philosophy.

V62 PROCEEDINGS OP THE AMERICAN ACADEMY

each particle we liave the component veh)cities u, v, w, parallel to the fixed axes OX, OF, OZ. These have the following expressions: —

^ ^ ^ dt' dt' dt'

X, y, z, t being independent variables, and «, /3, /, functions of them. If the disturbed condition is so related to the initial condition that every portion of the body can pass from its initial to its disturbed position and strain, by a translation and a strain without rotation, — i.e., if the three principal axes of the strain at any point are lines of the sub- stance which retain their parallelism, — we must have, —

Eq. (2) : — = ^ 'b z='i°- ^ =z^Ii -

dz dy dx dz dy dx

and, if these equations are fulfilled, the strain is now rotational, as specified." But these equations express that a d x -\- ^ dy -\- y d z, i& the differential of a function of three independent variables ; and there- fore, in order that there may be no rotation, a strain potential must exist. The forces which solicit the particles of tlie drop when it rests upon the liquid of less density in which it cannot diffuse are evidently their mutual attraction, a force arising from the superficial tension of the liquid, and one ai'ising from gravitation. It is evident, from a consideration of these forces, that, after the drop has suffered a strain at the surface, every poilion of the drop cannot pass from its initial position to the next following by a translation and a strain without rotation. For the drop tends to return from a shape api)roaching an oblate spheroid to that of a sphere. Equations (2) do not liold, and a strain potential does not exist, and tlierefore this drop must rotate. This rotation is not in general of the ring form. If, on tiie other hand, the drop of liquid can diffuse itself in the liquid through which it falls, each particle with the velocity u, v, w, is solicited at the moment of im- pact by a superficial tension, by the force of gravitation, and by a force arising from the rate of diffusion. In this case, there is no tendency of the body to reassume the spheroidal form in its passage through the liquid. On tiie other hand, to assume that each particle in the next state of the drop very near that which it assumes on striking the free surface of the liquid of less density, is translated without rota- tion, is to assume that each particle is compelled to move in restrained limits, which do not exist. For the components X\ Y^, Z^, of the attraction, which tend to make the non-diffusible drop reassume its spherical form, we have in the case of the diffusible the components

OF ARTS AND SCIENCES.

133

X, T, Z, of an external force arising from the superficial tension of the liquid, and the impulse given to the drop.

If we follow the notation of Poisson * and Helraholtz,t we shall have for the general equations of internal motion of a liquid : —

-rr 1 dp (fit I dii 1 du I dit h dx dt ' (/x ' dy ' dz

rl dp do , do t du I du

— '- = — -4- u— -\- V— -+- w—

h dy dt ^ dx ^ dy ^ 'I-

rr 1 dp dw 1 dw i dw i

Z -L =^ — + U — -4- V — H-

k dz dt ^ dx * dy '

W-

dz dw

I

' dz

dh \ dh I dh I dh Sh / ,\

— 4- u— -\- V— -\- w — = — (4) dt~ dx~ dy~ dz U ^ ^

du I dv I dw f-^

— -U — -I- — =. 0 (0) dx^ dy^ dz ^ ^

In which p is the pressure in a liquid at the point x, y, z; X, Y, Z, are the components of the external forces acting on a unit of mass; and h is the density. When tlie variation of h is infinitely small, we have Eq. (5). The forces X, T, Z, are considered to have a potential V. So that

X=ir, T^II. Z^.'-f Eq.(6)

dx dy dz

and the velocities u, v, w, a velocity potential qp. So that

u

d<i>

dtp dy

IV. = ^ Eq. (7)

dx' dv' dz

or, udx -f- vay -f- wdz = d(f,

and q) satisfying the equation

dx-' ' dy' ' dz^

which is what equation (5) becomes under the conditions expressed above. We must therefore have

du dy

du d~x'

do dz

dw dw du T-i /o\

cV dx = d-z ^^^•('^)

* Traitede Mechanique. t Crelle's Journ., LV., 1858.

dv dz	d'o 2^
dw 7G~	dii ^ d. 2r
du	d>; gy dx "^
dy

134 PEOCEEDINGS OP THE AMERICAN ACADEMY

equations similar to the equations expressing a strain potential. Helmholtz has shown that in the case of rotation of a fluid element, Eqs. (8) become

Eq. 9

and therefore " the existence of a velocity potential is inconsistent with the existence of rotation of the fluid element." We have seen from the equations of strain that the existence of a strain potential is incon- sistent with the rotation of a material particle. Let us now see if vortex movement can arise in a liquid from variation of density and pressure. Following Ilelmholtz's notation, we have, if t/; is a function

5i =:. ^ -]- rci^. + t>^ + w'!± Eq. (10) St at ' dx "^ du ^ dz A V >'

Calling S, y, ^, the components of the angular velocity, we can obtain their variations by substituting them in succession iu Eq. (10). If we eliminate X, T, Z, from Ecjs. (.'J) by the help of P^qs. (G), supposing that h and p are functions of x,y^ z, t, we obtain, introducing the values of ^, 7, "Q, from Eqs. (9) : —

_, /-,,\ 8f v/f'y r dw\ I dv I ^dw , 1 /dh dp dh dp\

Eq. (11) ^ = - S(- + -^-) + r- + C^, + 2T.U '^~d, -i)

and similar expressions for the variations of / and ^. If the variation of h is infinitely small, we obtain by the aid of Eq. (5) : —

Sf ^.dn I do I ydw

— = 5 \- y h t —

9( 'dx dx ' dx

If it is not infinitely small, we have the term

1 /dh dp fM dp\

2h\dz 'dy dy di)

which is independent of ^, y, t, and depends upon the variation of h and p. This term enters into the expressions for the variations in the angular velocities ; and shows, therefore, that a vortex movement can arise iu a process of diffusion by a variation in density and pressure, without the aid of initial angular velocities. This condition can be

OF ARTS AND SCIENCES. 135

shown experimentally by dropping a somewhat dense solution of one of the aniline colors into a mixture of glycerine and water. The orig- inal ring, after ceasing to move downward in the mixture, breaks up gradually into segments, which slowly in their turn assume the ring form. A mixture of water and glycerine is not necessary: jieculiar cusp-like figures indiv'ating tlie first stage of vortical movement can be seen whenever a thin stratum of one liquid slowly diffuses itself through another liquid of different density.

By a consideration of the equations —

e ^ + ("1 - t^)dt = e(^ + ^i dt^

« C+ K - ^o)dt = e(^:+^^dt^

given by Helmholtz, from which he draws the conclusion that " each

vortex line remains continually composed of the same elements of

fluid, and swim^ forward with them in the fluid," we see, on intro-

^>

duciug the new expressions which we have found for --, &c., P]q. (11),

St

that we approach nearer and nearer to this theoretical conclusion when the variations of h are smaller and smaller. Obviously, we should then obtain tlie most perfect rings Tvlien the drop and the liquid in which the motion takes place are composed of the same liquid. And, there- fore, a drop of water falling into loater must form a more perfect ring than that formed by a drop of any colored liquid of greater density than water.

The formation of these liquid rings is as fascinating and as simple an occupation as blowing soap-bubbles. All liquids falling from such a height that the surface of the liquid is not too much disturbed tO' enable the drup to be acted upon symmetrically by the forces at the free surfiice will form rings, if too great differences of density do not exist, and if the drop can diffuse in the liquid. The preceding mathe- matical discussion, as we have seen, shows us that a drop of pure water on striking the same element under the above conditions must neces- sarily assume the ring shape. This can be shown experimentally by covering the free surface of the water with a fine powder, or with mat- ter in a fine state of subdivision. 1 have found that an alcoholic tinct- ure of ginger, whicli gives on the surface of water a milky liquid consisting of particles iu a fine state of subdivision, answers the purpose

136 PROCEEDINGS OF THE AMERICAN ACADEMY

very well. Fine particles will be carried down by the drop, and will be seen to rotate in a vortex ring far below the surface. This fact can be stated, al^o, bj'- the employment of any of the aniline colors which are solvent in water, the falling drop consisting of a colored solution whose specific gravity does not differ sensibly from that of water. The metiiod that 1 have emploj^ed to produce the rings consists merely of a small glass tube, slightly smaller at one end than the otiier. A bit of cotton is wedged in nearer the larger end, over wliich a piece of flexi- ble rubber tubing is slipped. AVith the aid of the moutli, one can fill this tube with licpiid and eject it in drops at pleasure. The same appa- ratus enables us to form the rings beneath the surface of the liquid. With a tube bent horizontally, one can send the rings through a liquid in any desired direction ; and, by means of a three-way glass joint and a small india-rubber bag, one can send forth, by the same impulse, two rings whose paths make any desired angle with each other. By partly immersing the glass tubes connected with the three-way tube in the free surface of the liquid, and covering tiie surface of the water with fine powder, one can study the mutual behavior of half-vortex rings. A simpler method is to illuminate, by means of a gas-light, the bottom of a flat, white porcelain dish filled with water, and to observe the shadows of the half-vortex rings on the bottom of tlie dish formed by the movement of two spatulse along the surfiice. It can be readily seen, by this simple method, that a lialf-vortex ring moving near another in a parallel path and with a less velocity tends to follow in the path of the first ; and that two equal half-vortex rings moving in opposite directions along the same path separate into two vortices which move at right angles to the path of the original vortices. We can conclude, also, from this general discussion, that, whenever a mass of vapor of greater density than the surrounding air is suddenly formed in the higiier regions of the atmosphere, it tends to descend through it in a vortex ring.

The results of the preceding discussion are as follows : —

1. An an^dogy between the strain potential and the velocity poten- tial is indicated.

2. It is shown that the formation of liquid rings is a necessary result of the fumlameutal equations of strains and those of hydrodynamics ; and that tlu-y constitute a general and not a special phenomenon. A drop of water falling into water from a suitable height must assume a ring shape.

3. Vortices can and do arise in certain processes of diffusion.

4. Simple methods of studying vortex motion in liquids are given.

OP ARTS AND SCIENCES.

137

XI.

CONTRIBUTIOXS FROM THE PHYSICAL LABORATORY OF

HARVARD COLLEGE.

NO. XIV. — ON A NEW METHOD OF COMPARING THE ELECTRO- MOTIVE FORCES OF TWO BATTERIES AND MEASURING THEIR INTERNAL RESISTANCE.

By B. O. Peirce, Jr.

Presented, March 14, 1877.

The relative strengths of two currents which give ri?e to different deflections of a galvanometer needle are not easily compared, and therefore it has been the aim of pliysicists in making electric meas- urements to choose such methods as require the current through the galvanometer to be made either zero, or else equal in two given cases. The method of measuring resistances by Wheatstone's Bridge is an example of a '' nul" method. Mance's and Thomson's methods of measuring the resistances of batteries are examples of the class which require equal deflections.

Poggendorff's method of comparing the electromotive forces of two batteries is the only accurate method vehich belongs under either of these heads.

I have found that very accurate results can be obtained in the following way : —

Fig. 1.

The batteries to be measured are arranged as in the figure, with their electromotive forces conspiring, r is any small resistance. R^

138 PROCEEDINGS OF THE AMERICAN ACADEMY

and i?2 ^^^ resistances which may be varied until no current passes through tlie galvanometer. AVhen the current through the galvano- meter is nothing, the ratio of the electromotive forces of the two batteries is very easily found. Let HJ^ and K2 be tlie electromotive forces of the two batteries, and -5^ and B^ their internal resistances.

Kirclioff 's Second Law, when applied to the closed figure embracing the resistance £^, H^, G, gives,

JE, = (B, + 7?J 0 (1)

where (7 is the current traversing the circuit.

The same law when applied to the closed figure r, B,^, B.^, G, gives

B,= (r + B, + B,)0 (2)

Dividing (1) by (2)

(3)

In order to use this formula, we must know the values of i?^ and B^. These may be determined thus : Give to B., a little different value, and vary B^ until there is again no current going through the galvanometer. Repeat this operation with still a ditferent value of B^, and there will be three different values of the ratio of the elec- tromotive forces, which will give three equations to determine B^, B^,

E and —^. B. and R„ are most conveniently made large ; and in this

case, if extreme accuracy is not needed, we may neglect B^ and B,^ compared with R^ and R^.

It is, of course, not necessary to have any resistance corresponding to r ; but as it is often possible to get quite accurate results by making R^ and ^2 small resistances, and then varying r by means of a rheostat until no current traverses the galvanometer, a resistance r is inserted in the figure.

Tlie chief advantages of this method are : —

1st, its great accuracy.

2d, that the current through the galvanometer is made zero.

3d, that the circuit does not have to be broken during the com- parison.

4th, that the resistances of the two batteries are, very readily ob- tained without altering any of the adjustments, if their electromotive forces are constant.

The greatest disadvantage in this arrangement is that a large

OF ARTS AND SCIENCES.

139

current passes through the resistance coils. The current through the coils may be reduced by connecting, through a shunt, the battery- poles which are already connected by the resistance coils, and in this way one can avoid all risk of injuriou.^ly heating tlie fine wire.

The use of the shunt makes the formula which determines the ratio of the electromotive force of the two batteries a little more complex, but the mechanical work of the comparison is not altered.

Fig. 2.

C (Fig. 2) is the strength of the current going through the un- divided circuit. Cp and Cj are the strengtlis of the currents going through the shunt and through the resistance box respectively. Let S be the resistance of the shunt,

(7= (7,+ Co and C^{R^^R.^= C^.S

5+ /?! + /?,

.-. C=Ci

S

c. = ^

cs

Kirchoff's Second Law gives, when applied to the closed figures B^, R^, and G, and r, B.^, R.,, and G,

B, = B,G +

R,SC

5 + i^i + i?2

(1)

B.,= (r + B.^)G+^^^^^

(2)

140 PROCEEDINGS OF THE AMERICAN ACADEMY

Dividing (1) by (2)

E., (r + B,) (6 + E, + R.,) 4- li;S ^ '

wliich is the formula required.

NO. XV.— OX A NEW METHOD OF MEASURING THE RE- SISTANCE OF A GALVANIC BATTERY.

By B. 0. Peirce, Jr. Presented, March 14, 1877.

Of the many known methods of measuring the resistance of a galvanic battery, only two, those of Mance and Tiiomson, are found to give accurate results. A third method, which seems to work well in prac- tice, is this : —

A known resistance (r), a galvanometer of known resistance (G^), and the battery whose resistance is to be measured, are joined up in a simple circuit. The battery is shunted, and the deflection of the galvanometer needle is noted. This shunt is now removed, and the galvanometer is shunted, so that it gives the same deflection as before. A knowledge of the ratio of the resistances of the shunts gives the resistance of the battery by means of a simple formula. Let E be the electromotive force of the battery, and B its resistance, and let ^S* and G be the resistances of the shunts. In the expressions that follow, Cff, Csi ^'^d Ca denote currents passing through the galvanometer and the two shunts respectively.

When the battery is shunted, the whole current in the circuit is

8^ r -}- G

Kirchoff 's Laws give

(7 = Cff -I- C; and (T^ . ^ = Ga{r + G)

therefore

C^G,^A±L^r_0) ^2)

o

OF ARTS AND SCIENCES. 141

Equating the secoud members of (1) and (2)

i:S= C,|^(r+ G)-lrB{S-\-r-\-G)'^ (3)

When the battery shunt is removed, and a shunt put across the terminals of the galvanometer, the whole current traversing the circuit is

Kirchoff's Laws give

C = Ca-\- a and C^.G= Cg.G therefore

C = C, (^i^) (5)

Equating the second members of (4) and (5)

Ea= cJ^G<s^(r + B) {G-]-o)^ (6)

Dividing (3) by (6) and cancelling, we have, since the current passing through the galvanometer is the same in both cases,

[f7(T + (r + i?) ( (? + o)-]S = \_S{r J^ G) -\- B{S -\- r Jr G)']a or if

(;._|_ G)8— G

In practice, the terminals of r are connected to the galvanometer and to the battery respectively by binding-screws with three wire holes in each. One terminal of a Wheatstone's Rheostat is perma- nently fastened to one pole of the battery, and the other terminal is connected, first with the binding-screw on one side of r, and then with that on the other side. The handle of the Rheostat is to be turned until the galvanometer needle gives the same deflection in the second

142 PROCEEDINGS OF THE AMERICAN ACADEMY

case as in the first, and the ratio of the lengths of the shunt are taken to represent the ratio of their resistances.

With a piece of uncovered copper wire, not more than two metres long, and a resistance r equal to only twenty-four one hundredths of an ohm, I have obtained results which are quite as good as those obtained witli a box of resistance coil, using Thomson's method.

r should be a small resistance of not over five ohms for a long-coil galvanometer, and not over three ohms for a short-coil galvanometer. This method offers some advantages over that of Thomson, but it is not generally as good as the method due to Mance.

OF ARTS AND SCIENCES. 143

XII.

NOTE OX THE DETERMINATION OF THE LAW OF PROPA- GATION OF HEAT IN THE INTERIOR OF A SOLID BODY.

By B. O. Peirce, Jr.

Presented April 11th, 1877.

Newton's experiments upon the amount of heat communicated from a body ^ to a neighboring body B, at a lower temperature than A, led him to think that this amount was directly proportional to the difference of temperature between the two bodies. In 180o. Biot, assuminof that Newton's results were reliable, conceived that the same law must hold for the communication of heat between two neighboring molecules in the interior of a solid body, and he compared the observed temperatures at different points of a long bar heated at one end with the temperatures calculated on the assumption that the flux of heat in the direction x is represented by

dv dx

where y. is constant for the same body and v is the temperature of the point under consideration. Fourier — whose " Tlieorie de la Chaleur " was written in 1811, but not published until 1822 — followed Biot

in assuming

dv dx

to represent the flux of heat in the inside of a body, and

7 dv dx

the radiation at its surface, where x and h are different constants which he calls respectively the " conducibilite propre " and '• condiicibilite relative a I'air atmospherique." Just before Fourier's work was publijjhed, MM. Dulong «nd Petit showed that the amount of heat communicated from one body to another depends not only upon the

144 PROCEEDINGS OP THE AMERICAN ACADEMY

difference of their temperatures, but also upon the absolute tempera- tures of each. Poisson published, in 1835, his ''Theorie de la Chaleur," in which he assumed that the expression which Dulong and Petit had given for the loss of heat from radiation also represents the passage of the heat from molecule to molecule in the interior of the body. Libri, shortly before Poisson's book was pu!)li>hed, presented to the Academy of Sciences a paper in which he assumed that Fourier and Biot were correct in their hypothesis that the internal flux of heat could be written

, dn

dx

but that the law of extra radiation was that stated by Dulong and Petit. In 1837, Kelland published his "Theory of Heat." He applied Libri's hypotheses to the problem of determining the final distribution of heat in a ring, and showed that the solution thus arrived at was not very different from that wliich Fourier had de- termined. In other* respects, Kelland simply gave Fourier's work with corrections, as his object was to furnish a book for students. In 1841, Professor Kelland made a report to the British Association for the Advancement of Science " On the Present State of our Theoretical and Experimental Knowledge of the Laws of Conduction of Heat."

In this report, Kelland says that, although olyections might be made to the particular assumptions of Fourier, Libri, and Poisson, it is very probable that the flux of heat in the interior of a body may be written

where c is a constant depending upon the bofly and /{i") is some un- determined function of the temperature. Kelland assumed a particular value for f{v), and compared the temperatures calculated from the different hypotheses of Fourier, Libri, Poisson, and himself, with the corresponding temperatures observed by Biot in his experiments upon long bars. This comparison does not give the jDreference to any one of the different assumptions. Since 1841, nothing of any importance has been done, so far as I know, in the general theory of heat con- duction. Lame, whose "Theorie de la Chaleur" was published in 18G2, follows Fourier in his hypotheses, and those writers who, like Sir William Thomson, have had occasion to discuss practical questions about the cooling of bodies, have also made the same assumptions,

OF ARTS AND SCIENCES. 145

since the error thus introduced into their calculations is necessarily less than those arising from eri-ors in observing the phenomena.

Dulong and Petit's experiments showed that Fourier's assumption with regard to the flux of heat at the surface of a body due to ladia- tion was wrong, and Principal Forbes's experiments upon heated metallic bars showed that, in order to write the ^ux of heat in the interior of a body

do

dx

X must be regarded as a function of the temperature. Forbes's ex- periments evidently offer no objection to Kelland's hypothesis, for

— q,(v)$ and — c ^M dx dx

are equivalent expressions, if

(p{v) = cf'(v).

The first step in determining the form of the function y is made by showing that it must satisfy a differential equation which when the heated body is at its final state, reduces to Laplace's Equation.

Consider the element of volume dxdydz, which has one of its angles at the point (x, y, z) and its diagonally opposite angle at {x -\- dx, y -\- dy, z -\- dz). During the instant dt, the flux of heat across that face of the element which contains the point (x, y, z) and is parallel to the coordinate plane xy, is

F{v, z)= — c ^ dxdydt.

The amount of heat which flows out at the opposite face of the element is obtained by developing -F(t', z) by Taylor's Theorem :

F(v J^dv,z-\-dz)= — c ^ dxdydt — c ^^ dxdydzdt.

The flux across the second face is less than the flux across the first face by

c I ' dxdydzdt.

Considering each of the other pairs of opposite faces, it is evident that in the instant dt a quantity of heat equal to

VOL. XII. (n. S. IV.) 10

146 PROCEEDINGS OP THE AMERICAN ACADEMY

have been arlderl to the element. Let Q be the total amount of heat in the molecule, then

If Laplace's Operator is written " — V^,"

-^ = — cV-f(v) dxdydz.

Let s be the specific heat of the body which Dulong and Petit have shown to be a function of the temperature, and lets = ^\v), then

d^Q ^ d^v . "^'s . dxdydz,

^^(^) 4f = - "^'-^(^^ If r"^ = x^ -{- ip' and (jp = tan"~^ —

— \/Hiv\ = ^!^ -J- ^'^") I ^/Tf) , ^y»

-^ ^ ^ df^ "> r^ . cl(t>-^ "I" r . dr "^ dz^

•' '^'^''^ ir = + ' [d7^ + 77dF+ ?W^ + d7^)-^^'^

If the body has reached its final state, the element loses as much heat in any given time as it gains, so that f(^v) must satisfy Laplace's Equation, or

vy(r) = 0.

Consider a thin plate of metal of practically infinite extent, and of which all points are at a uniform temperature. Let this plate be laid upon and covered witii some perfectly non-conducting material, so that there can be no flux of heat perpendicular to the [)lane of the plate, and let a single point be heated by means of a copper wire pushed through the non-conducting material upon which the f)late lies.

There will be a fiux of heat from tlie heated point in all directions in the plane of the plate ; and, if the plate is homogeneous, the flux will be the same in all azimuths.

After the plate has reached its final state, the amount of heat added to each element of the plate will be the same that flows out of it, and dQ = 0. If the plate lies in the coordinate plane xy, there will be no flux in the direction of the axis of z, and hence

d'f{") — 0 . -d7^ ^'

OF ARTS AND SCIENCES. 147

and, if the plate is homogeneous,

Therefore /(r) must be a solution of the differential equation or f{v) = J + i? log r,

and the flux = — c

clf\v) ^cB

dr r

Consider a second plate of metal in every way like the first, only that it is heated at two points by means of a Y shaped piece of copper which is itself heated at its stem. The two arms of the Y are pushed through the non-conducting material and are of equal lengths, so that the two points shall be equally heated.

If Tj and r^ are the distances of any point from the two heated points, it is evident from the theory of conjugate functions that

f(v) is constant along any curve of the system [j\r..^ = const.] If a is the distance of the heated points from each other, the equation of the system of curves for any one of which /'(y) is constant may be written

(x^ + /)((x-ar + /)=!'.

Before the plate is imbedded in the non-conducting material, let it be covered with a thin layer of a mixture of parafRne, rosin, and wax, and after it has been heated long enough to have sensibly reached its final state let the source of heat be removed; then, if there is a clean line of demarcation between the wax that has been melted and that which has not, the form of one of the isothermals can be studied at leisure. Wherever y(r) is constant, v must be constant unless f(^v) is an equation of an infinitely high degree, which is inadmissible; and conversely, if v is constant along any curve, /(y) must also be constant at all points on that curve. If the isothermal traced by the melted wax is a curve whose equation is i\r^ = c, it will be safe to assume that the flux of heat in the intei'ior of a body is

_ c "^^^"^

148 PROCEEDINGS OF THE AMERICAN ACADEMY

as Kellaud assumed. By use of a suitable arrangement, it would be very easy to use such ranges of temperature as should make the experiment decisive. If the points were unequally heated by accident, the wax curve would not be symmetrical with respect to a line per- pendicular to that joining the two heated points. There could be no trouble with lack of homogeneity of the plate, as preliminary experi- ments show that from a single heated point the curve is perfectly symmetrical and distinct, with a probable error iu finding the line of demarcation practically insensible. I am indebted to Professor Gibbs for the suggestion that the New Hampshire Infusorial Earth might be advantageously used as an almost perfect non-conductor of heat.

Whatever might be the result of a series of experiments like those referred to above, it is evident, from the differential equation, that Fourier's solution cannot be a correct one. If the uniform tempera- ture of the plate were taken as the zero of the scale, the temperature of any point in the plate due to the two heated points would be tho sum of the temperatures that would be given to the same point if each heated point acted alone. On this hypothesis, it would be very easy to find a point in the plate so situated that, when the plate had reached its final state, the point would have a temperature nearly double that which either of the heated points have, which is mani- festly absurd. It does not appear that writers upon this subject have noticed this fact.

If experiment shows, as it probably will, that the propagation of heat in the interior of a solid is determined by the expression

— c^JM,

dx

it will not be hard to determine J{v) experimentally. The infusorial earth, it is believed, will prevent any sensible loss of heat from con- duction or radiation, so that the flow of heat in the plate will be de- termined solely by the law of internal flux. Let a plate of any metal other than copper be heated at a single point, and after it has reached its final state let the temperatures of the different points of the plate be determined relatively by means of the thermoelectric currents obtained by touching different points of the plate by the copper ter- minals of a Thomson's Short-Coil Galvanometer. These terminals are to be held by wooden pincers, and pushed through the light infuso- rial earth so as to explore the points of any line radiating from the point where the heat is applied.

OF AETS AND SCIENCES. 149

Let Tf,, r^, r„ r.j, &c., be a series of points in such a line determined by experiment, so tliut the galvanometer gives the same deflection when one terminal is at /•„_! and the other at r« as it does when the first terminal is at r^ and the second at r.^. If v is the temperature of all points upon the circle whose radius is r^, the temperature of all points at a distance from the heated point equal to r^ will be (v — V*'), and all points at a distance of Vn will have a temperature equal to (v — 7iVv). The temperatures may be determined as a function of r, [y = qr(r)] by obtaining the equation of the curve drawn by plotting the temperature as abscissas and the corresponding values of r as ordinates ; and tlie form of the function y may be mathematically obtained from the equation.

/(gr(r)) = ^' + ^'logr,

A' is the value of /(f/;(l)).

Kelland unintentionally says that the assumption of

dflv) ^ dx

as the law of flux will only necessitate the writing off(v) instead of V in Fourier's formulas. This statement is evidently only true when these formulas refer to a body which has attained its final state.

Mr. E. B. Lefavour and myself are engaged upon the experimental work laid out in this paper.

Harvard University, April 4, 1877.

150 PROCEEDINGS OF THE AMERICAN ACADEMY

XIII.

ANTIGENY, OR SEXUAL DIMORPHISM IN BUT- • TERFLIES.

By Samuel H. Scudder.

Presented, March 14, 1877.

In bis work on Selection in relation to sex, Darwin discusses the dif- ference of coloring which frequently distingui.shes the sexes of butter- flies, and concludes that "the male, as a general rule, is the most beautiful, and departs most from the usual type of coloring of the group to which the species belongs." (op. cit. i. 390.) Of the first proposition there can be no doubt; but, in the second, two distinct elements appear to be confounded : the separation of these is the object of the present eommunicalion.

Sexual dimorphism, or antigeny,* as exhibited in butterflies, is of two kinds, — colorational and structural. Colorational antigeny again may be divided into two classes: the first including those cases in which it is partial ; the second, those in which it is complete.

As one example of partial antigeny, we may take Ci/aniris pseudar- giolus (Boisd.-LeC). In the south, a portion of the females of the spring brood have the upper surface of the wings uniformly brown ; another portion have the greater part blue, like the male ; in the north, all the females are blue. In Jasoniades Turnus (Linn.), the males, and in the north all the females, are yellow above, heavily banded with black ; in the south, a large proportion of the fem;des have lost the yellow ground, and become wholly black ;, while others retain the universal ground-tint of the male. The dark female of Atrytone Zahuloa (Boisd.-LeC.) was for a long while considered a species dis- tinct from the normal female, in which the tawny colors of the male are shared by its mate.

* This term, signifying opposition or rlivcrsity of the sexes, is proposed to avoid circumlocution; for tliere are so ni;iny forms of sexual dimorphism requiring specific names, that a compound term for the general phenomenon becomes inconvenient.

OF ARTS AND SCIENCES. 151

These are all cases of melanism, and may be taken as examples of a class; in the first two, perhaps iu all, it is only toward the southern part of the insect's range that the melanism appears, and is in accord- ance with the general rule that melanic antigeny is more common at the south, while its opposite, albinism, is more frequent toward the north.

Albinism, for instance, is a common feature in the northern genus Enrynms. In our common E. Philodice (God.) and E. Earytheme (lioisd.), many females may be found in which the bright yellow or orange of the upper surface is replaced by a sordid greenish-white; and if we go farther north, or to higher altitudes, we shall tiud other species, iu which the albinism has become complete, affecting all the females.

It is a curious circumstance that, while albinic antigeny finds its most complete expression in high tem[)erate regions, and melanic an- tigeny prevails toward the tropics, the albinic females of a partially antigenic sj^ecies never appear in the spring brood, but increase in numbers throughout the hot season ; while, at least iu the case of the blue butterfly mentioned, the melanic females emerge in early spring, are confined to this biood, and are replaced in warmer weather by the gynandromorphic females ; thus, spring apparition appears to be corre- lated with southern distrIl)ution, and summer apparition WMth northern distribution : these two phenomena appear, in either case, to be directly antagonistic.

Although both albinism and melanism may become complete, par- tial antigeny, wherever it exists, is confined to the phenomena of melanism and albinism, and does not extend to the more varied forms of complete colorational antigeny, to which reference will now be made.

In the male of Xanthidla Nicippe (Cram.), the black bordering band of the wings is sharply defined, and extends across the entire outer margin ; in the female, the band is blurred, and stops abruptly before it reaches the lower angle of the front wings, or has half trav- ersed the hind wings. In Redone Brettus (Boisd.-LeC), the female is very dark-brown, almost black, with two little yellow spots in the middle of the front wings ; while the male differs totally, being tawny with indented brown borders and an oblique black dash in the middle of the front wings : at first glance, no one could suppose them iden- tical. In Semnopsyche Diana (Cram.), the male is a rich dark-brown with a very broad fulvous margin upon all the wings, marked on the front wings by one or two rows of black spots. The female, on the

152 PROCEEDINGS OF THE AMERICAN ACADEMY

Other hand, is a ricli purple-black, with no trace of fulvous, but with the space where it belDiigs occupied on the fore wings by three rows of white spots and dashes, and on the hind wings by two belts of blue, broken into spots, one of the belts narrow, the other exceedingly broad. In Erora lata (Edw.), the male is wholly brown, with a border of deep blue on a 23oi'tion of the hind wings ; while in tiie female, the blue has extended so as to cover almost all the hind wings, and even the base of the fore wings. But it is in the Coppers ( Villicantes) that this ph(?nomen<)ii is most common. Here the females are usually of a fulvous color heavily spotted with black, and particularly noticeable for their conspicuous broad dark border, and a row of spots crossing the wing beyond the middle ; while the males are either of some dark- brown shade with a purplish gloss, or of a fiery hue, almost always without any border or spots.

Now in all these cases of colorational antigeny, it is the female, and never the male, which first departs from the normal type of coloring of the group to which the species belongs. Occasionally the feminine peculiarity has been transmitted to the male, and, by this means, a new type of coloration estal)lished in the group ; but I recall no case where the male alone departs from the general type of coloring pecidiar to the group. This is precisely the opposite conclusion to that wliicli Darwin reached. He gives several examples on the authority of Bates, which certainly favor his conclusion, but may, at the same time, be explained from the opposite point of view. He gives other examples from the European blue butterflies, which not only do not support, but even oppose, his general statement.

Take the case of Semn. Diana, than which we could hardly find a stronger, since the group {Dnjades) to which it belongs is remarkably uniform, exhibiting in all its numerous membei's the same character- istic play of fulvous and black markings. Tiie male of S. Diana is indeed very unlike most otlier fritillaries, but it retains, nevertheless, abundant traces of the same style of ornamentation, and has precisely the same colors, while the female departs widely from the charac- teristic features of ornamentation, and, in addition, loses every trace of fulvous, so that no one at first glance woidd recognize it as a member of the group. Take again Earyinus Philodice and its allies. In some species, indeed, there are only pale females ; but in others all, or most of the females, are yellow or orange, like the males ; and any one who knows how yellow and orange tints prevail through- out the group of Fugacia will acknowledge that the color of the males is normal. So too with the Blues {^Adolescentes),\\\\\(A\ Larwiu him-

OF ARTS AND SCIENCES. 153

self quotes : in almost all of them, both males anrl females are of some shade of blue ; in comparatively few, the males are blue and the femnles brown ; in exceedingly few, both sexes are brown ; and the very fact that they are familiarly known as " Blues" is a popular recognition of the prevailing color. In the group of Skippers to which H. Brettus belongs (^Aslyn), tiie prevailing colors, at least in the temperate zones, are certainly tawny and black, or brown ; the latter, marginal. This is the case with the male of H. Brettns, while the female diverges from the type in becoming wholly brown. In Jusonlades TiiniHS, where we sometimes have a black female, it is more ditficult to decide what should be considered tiie normal color, owing to diversity of view upon the relationship of many of the Swallow-tails ; but. to judge only from those agreed by all to be most nearly allied to it, there can be no question whatever that the striped char.icter prevails.

It will also be noticed, in this last case and others given, that wher- ever partial antigeny or dimor[)liism is confined to one sex, it is always to the female : there seems to be no exception to this rule. In these instances, on my hypothesis, half of the females depart from the type ; on Darwin's, half of the females, and ail of the males. But if, on Dar- win's theory, sometimes one-half, and sometimes three-quarters of a species has diverged from the type, why does it never happen that only one-fourth of the sjiecies diverges ? This seems to be a very per- tinent and damaging inquiry.

The instances given by Darwin, which strongly sustain his view, are drawn from specimens of the Sotith American genus Epicalia, found in the rich cabinet of Mr. Bates. The facts, as stated by him. are these : There are twelve sjjecies of the genus discussed by him ;* of these, nine have gaudy males and plain females ; one has plain male and plain female ; and two have gaudy males and gauily females. The plain females, he adds, '' resemble each other in their general type of coloration, and likewise resemble both sexes in several allied genera, found in various parts of the world." To examine this case fairlv would need a large collection of exotic butterflies. If we confine our- selves to Epicalia, we evidently cannot say whether the gaudy or the plain coloring be normal : there would be less variation from the standard on the supposition that the gaudy were the normal t3'pe, and in this case it is the female which has departed from the type ; but the difference is not enough to form an objection. It is only when we look outside of Epicalia that judgment seems to lean toward Darwin's

* Kirby, in his last general catalogue, gives fifteen.

154 PROCEEDINGS OF THE AMERICAN ACADEMY

side ; but, from the unfortunate want of material, I cannot fairly dis- cuss this point.

Take, however, another case, which appears to be equally compli- cated,— our native Coppers (Villicaiites). We have one species in which both sexes are fiery red marked with black ; another where both are fulvous marked with black ; others where both sexes are brown ; and several where the male is brown, marked with fulvous, and the female fulvous, marked with brown ; others where the male is wholly brown, and the female fulvous, spotted with brown ; and again others with fiery male, and brown female. We have nearly every possible variation, but the prevalent feature is a dark male, often with more or less metallic reflections, which sometimes increase so as to give the insect a fiery copper hue ; and a fulvous, spotted, and margined female. I do not see how we can po.^sibl}' discover, with any certainty, fi'om within tlie limits of the group of Coppers, what sliould be considered the normal type. Nor are we much better off in an examination out- side the group: there the prevailing tint is either brown or blue; and I am inclined to think that brown, tending strongly to copper, should be considered the normal type ; in which case the males are normal, and the species generally antigenic.

But sexual dimorphism is not confined to color or pattern ; there is also structural, as well as colorational, antigeny. This term embraces all those minor features which, in these and other animals, have been classed as accessory or secondary sexual peculiarities. Structural antigeny is always complete, and, in direct opposition to the features we have been discussing, is wholly confined to the males.

In butterflies, structural antigeny is mostly confined to the wings and the legs ; occasionally it appears in the antennfe. Sometimes it affects the contour of the wings. One of the most conspicuous cases among our own butterflies is in Slrymon Titus (Fabr.), where the fore wings of the male have a poinded tip, and the hind wings have the inner angle sharply defined ; while in the female both the tip of the fore wings and the inner angle of the hind wings are broadly rounded.

Or it may affect the direction of the veins of the wings. Usually the difference between the sexes is slight, and concerns the point of origin of one or two of the upper branches of the subcostal vein of the fore wings ; but occasionally it is very marked, as in many hair-streaks, such as Thecla Edwardsii Saund., where the branches of the sub- costal vein near the end of the cell are thrown far out of place to accommodate a patch of peculiar crowded scales ; this patch itself,

OF ARTS AND SCIENCES. 155

moreover, is a feature of the males alone, and occurs in many hair- streaks wliere the position of the veins is not altered.

One of the most curious patches of tliis kind is found in the males of some species of Eurymus, althouj^h wholly absent from others inti- mately allied to them. It is a little patch of lustreless scales, which occurs at that part of the base of the hind wings which is always cov- ered by the front wings, so that it is quite concealed from sight. Patches of a different nature also mark the male sex ; thus, next the middle of the lower median vein of the hind wing of Danaida Plexip- pus (Linn.), and in some of its allies, we have a heavy thickening of the membrane, conspicuous from its covering of black scales.

In very many males of the larger Skippers {Hesperides), the front edge of the fore wing is abnormally expanded, and folded compactly upon the upper face of the wing, so snugly that often it can oidy be discovered with the lens; moreover tlie scales within this have turned to white silken floss, which, when the fold is raised, contrast conspicu- ously with tiie ordinarily dark surface of this part of the wing. In certain Swallow-tails (E(/m'tes) also, the inner border of the hind wings is folded back in a similar, though looser, manner ; but is so much lar- ger that, when opened, it often exposes a white downy surface as large as the abdomen.

Then again there is much variety of male adornment in special mod- ifications of hairs or scales upon ihe wings. The patch of tiie hair- streaks already mentioned is one instance of this; another example is found among the Dryadcs, in a row of long, fulvous, partially erect hairs along the upper edge of the cell of the hind wings ; this is accom- panied by a curious apparent thickening of the veins in tlie middle of the fore wing, due altogether to the presence of a multitude of small and densely clustered black scales, crowded against the veins at this point. A faint oblique ])atch of minute and crowded lustreless scales, accompanied by long silky hairs, is often seen crossing the wings of some of the Satyrids ; but this feature finds fullest expression iu the Astyci, or smaller Skippers, where a large proportion of males liave a patch or oblique dash of peculiar scales covering veins and membrane indiscriminately, but usually, and in our native butterflies ahvaj^s, occu- pying the middle of the front wing, and crossing the median veins obliquely near their base. This dash is variously formed, but the scales which compose it are much larger than the ordinai-y scales, are black, and frequently partially erect. They may also differ in various parts of the patch itself, and alter its character abruptly ; for in- stance, some comparatively huge and brilliant scales may occupy the

156 PROCEEDINGS OF THE AMERICAN ACADEMY

middle line, and be buttressed by a multitude of minute, crowded, lus- treless scales ; or there may be at one point a sort of whirlpool of large party-colored scales, imbricated, in the most regular fashion, like the normal scales, and, beyond them again, a multitude of the minute, crowded, lustreless fcales. These peculiarities, however, must be studied with a glass ; the naked eye may indeed discern that the patch differs in different insect?, but the general effect in all alike is a vari- ously formed velvety patch or olilitpie streak of black.

It may be remarked, in passing, that wherever antigeny, colorational or structural, manifests itself in the wings of butterflies, the differences between the sexes almost invariably occur upon the upper surface, and generally upon the front wing only ; it occasionally happens that there is a slight difference in the general tone of color on the under surface of both sexes, corresponding to what appears above, as in Semrwpsyche Diana ; but it rarely affects the markings of the wings. The differ- ences upon the upper surface, however, and especially upon the fore wings, are, as we have seen, often conspicuous and very curious. One can scarcely doubt tliat tliis is in direct relation with the general absence of all ornamentation from the lower surface of both wings, and usually also from the upper surface of the hind wings, of moths.

Sexual dimorphism in the legs shows itself in the proportional length of the different pairs in the two sexes, in the special development of certain joints, in the appendages, and in the clothing. It ap|)ears remarkably in the appendages of the two higher families of butter- flies, Nijmphales and Rnrules, and especially in the latter family, where the terminal appendages of the fore legs are nearly or quite lost in the males, and are as cons|)icuous as on the other legs in the female. I have not discovered that the differences in the length of tlie leg-joints follow any general law, although tliere are few of our butterflies whose sexes do not vary in this particular ; this form of antigeny is also most conspic- uous in the Rurales. The males of certain VilUcantes ( Chrysophaniis, Epidemia, Heodes, Feniseca) also present another curious feature in a tumid swelling of the basal joint of the middle and hind tarsi. Finally, the fore legs of the males of Nijmphales are frequently furnished with a spreading brush of hairs ; or, in other butterflies, the thighs and shanks of the middle and hind legs are supplied with curious pencils or fringes of stiff hair, which appear to have the same sigaificauce as similar adornments in higher animals.

Darwin supposes that these various male appurtenances, which occur throughout the aniratd kingdom, have all arisen by natural selec- tion, — that one of rival males being selected as a mate whose outward

OF ARTS AND SCIENCES. 157

cliarms are greatest. He certainly brings powerful argument and a strong array of facts to support this hypothesis ; but what then shall be said of tlie following ilhistration of structural antigeuy ; viz., the presence iu many males, but in no females whatever, of scales of the most exquisite beauty and delicacy, scattered among tlie more common sort, and invisible to the naked eye ? Even with the help of the microscope, they can often only be discovered by ruffling the wing, and forciljly extracting them from their concealment; and, so far as we can see, they give to tlie wing no peculiar character by which it may be distinguished from other wings.

These peculiar scales, or androcouia, as they may be called in ref- erence to their masculine nature, were first noticed by Bernard Deschamps more than forty years ago,* but have never been properly studied tliroughout the butterflies. Deschamps called them plumules, from their feathery tips ; but the term is utterly inappropriate to most of them ; and their form is so varied that only some word expressing their masculine character should be accepted, since this is their single common peculiarity.

These androconia are very capricious in their occurrence ; a number of allied genera may possess them, while a single genus, as closely allied, may be quite destitute. This is true throughout the butterflies, and yet there are large groups in which they are altogether wanting, and others in which their absence is extremely rare. In the highest butterflies, they are long, slender, and invariably feathered at the tip. In one small group (the Hdiconii), they are toothed as well as feath- ered. With the exception of the Heliconii, they may generally be distinguished from ordinary scales by the absence of any dentation at the tip. In the Voracia, they are fringed, and, with a single known exception, their extreme base is expanded into a sort of bulb ; else- where, even in the other Pierids, they are not fringed, but have a smooth rounded edge. In the Adolescentes they assume a battledore or fan shape, with a smooth edge, and are generally beaded, and more heavily striate than the scales. The same is true, but with more vari- ations, in tiie Villicantes and Ephori, where they have been considered wanting. In the Equites, where also they have been supposed to be wanting, they differ but little from the scales, but are much smaller and incjre coarsely striate. In the Urblcolce, where no one has hitherto recognized them, they present the greatest variety in the same individ-

* Recherches microscopiques ?ur I'organlsation des ailes des Le'pidopteres, Ann. Sc. Nat. [2] III. 111-37 (1835).

158 PROCEEDINGS OF THE AMERICAN ACADEMY

ual ; in one group (Hiesperides) there are hair-like androconia, and others wliich are exceedingly hirge and spindle-shaped. In the Astyei, besides hair-like and gigantic androconia, there are usually some which are spoon-shaped, with long handles.

As a general rule, these androconia are present in the patches to which we have alluded as forming oue phase of the antigenic charac- ters of the male ; but often, as in the Adolescentes and Voracia, they are scattered indiscriminately or in rows over the upper surface of the wings ; and there are many patches, like those at the base of tlie hind wings of some Fagacia, and next the median vein of the same wing in Dan. Plerippus, where androconia are not found. They do, how- ever, sometimes occur in patches on the hind wings, as in the fetid next the inner margin of the Equltes ; but, with the exception of the discal spot of the Ephori, they seem to be present in all patches found on the front wings ; occasionally forming the principal part of such patches, as in the Callidryades, and again taking no part in the display. Take, for example, the Dryades, where so many small black scales are crowded against certain veins as to give them a thickened appear- ance ; the androconia are also present in great numbers, but entirely concealed ; only by removing the scales can even the tassels of their long and slender blades be seen. Perhaps even more curious than this is the arrangement by which all the androconia of the Equites and Hesperides are tightly enclosed in a fold of the membrane ; it is not impossible that this fold can be opened at vvill by the insect, and it would then become conspicuous, and probably an attraction to the but- terfly's mate ; but what possible advantage can there be in partially or wholly concealed androconia, scattered separately over the wing ? In some Adolescentes, they are exceedingly scarce, numbering not more than one to a hundred scales, and the exposed surface of this one not one-tenth that of the scales about it. One might search an hour with a microscope over an unruffled wing and overlook it; indeed, it is as the merest speck of dust in a dust heap. Does the siglit of these creat- ures surpass our power of vision with the microscope ? The theory of sexual selection proposed by Darwin appears to fail here, just where it should aid us most.

OF ARTS AND SCIENCES. 159

XIV.

CHARACTERS OF SOME LITTLE-KNOWN OR NEW GENERA OF PLANTS.

By Asa Gray.

Read May 9, 1877.

CANOTIA, Torr., Genus Rutacearum.

Flores hermaphroditi. Calyx parvus, qiiinquelobus, persistens ; lobis latis sestivatione imbricatis. Petala 5, hypogyna, oblonga, utrin- qiie obtusissima, basi lata iuserta, aestivatione imbricata, intus medio costa prominula instructa, decidua. Stamina 5, hypogyna, calycis lobis opposita : filamenta subulata, petalis parum breviora, persistentia : antherje oblongo-cordatae, introrsae, sinu profiindo apici acutissimo filamenti affixis, mucrone parvo apiculataj ; localis iutus longitudi- nallter deiiisceiitibus. Pollen madidum tricorne. Discus iiullus. Ova- rium gynobasi crassa eoque multo ranjore inferne leviter 10-sulcata im- positum, o-loculare, stylo crasso demum elongando superatnra : stigma parvum, leviter 5-lobum ; loculis ovarii oppositipetalis. Ovula in loculis saepissirae 6, angulo iuterno biseriatim inserta, subhorizontalia ; micropyle int'era. Capsiila ovato-fusiformis, lignescens, epicarpio tenui subcarnoso induta, 5-locularis, ab apice 10-valvis (primum septicida, mox loculicida), portionibus styli persistens 10-fissilis superatis ; columella nulla. Semina in loculis solitaria vel bina loculum implentia, adscen- dentia, subovata, complanata ; testa subcoriacea creberrime papillulosa inferne in alam latam membranaceam nucleo sublongiorem producta. Embryo in strato tenui albuminis carnosi rectus ; cotyledoiiibus ovali- bu3 planis ; radicula breviuscula, infera. — Arbuscula 10-'20-pedalis, prorsus apliylla. glaberrima ; ramis alternis spartioideis viridibus rigidis nunc spiuesceutibus striatulis cicatricibus parvis remotis brunneis notatis ; inflorescentia secus ramulorum racemiformi ; pedunculis bre- vissimis fasciculatim vel cymoso-3-7-floris ; pedicellis articulatis ; brac- teis parvis squamiformibus ovato-subulatis oppositis deciduis ; corolla alba; glandulis ordinis evanidis.

160 PROCEEDINGS OF THE AMERICAN ACADEMY

Canotia holacantha, Toit. in Pacif. R. Rep. iv. G8 ; Benth. & Hook. Geu. i. 616 (where the radicle is inadverteutly said to be superior); Brewer & Watson, Bot. Cahf. i. 190. — Arizona, in the arid desert region, especially along mountain water-courses, Emory, Bigelow, and various other collectors, in fruit, first collected in flower by Palmer, and recently by Rothrock in Wheeler's Expedition.

A genus of hitherto undetermined affinity. Dr. Torrey, who knew only the fruit, with calyx and filaments persistent at its base, compared it with Eucryphia ; upon which Beutham and Hooker appended it, alono- with that genus and Euplironia, to Rosacea:, tribe Qalllajece. What- ever may be said of those genera, this is certainly not Rosaceous. Baillon, the first botanist to publish any thing upon the genus since the flowers were known, and who describes the '• discum crlandulosum incrassatum " under the ovary (but wrongly describes the calyx as valvate and the ovules as anatropou-), refers Canotia without question to Celastracece.* This is better than Rosacece, and the inferior radicle tells in its favor, as against the view which I take, having now for the first time examined the floweis. But I am confident that the plant belongs to the Rutacece. The structure of the gynol)ase, as I should call it, points strongly in this direction. This large and fleshy or, when dry, rather corky body upon which the ovary is mounted is broader than the latter in the blossom, as well as of twice its height; and is so confluent with it that, upon superficial observation, it would be taken for a component part of it. But it is solid within, and has a papillose- glandular surface, unlike that of the ovary it supports, which is smooth. Its likeness to that of Rue is manifest ; and in Thamnosma the same body becomes stipitiform. I find no trace in Canotia of a proper disk around the base of this, which is conspicuous in Thamnosma, As the fertilized ovary enlarges, it soon becomes broader than the gynobase as well as longer ; in the fruit the latter so inconspicuous that it has been ovei'looked. The wood and bark are not bitter to the taste, in the manner of most Simarubacece (which in a comprehensive consideration of relationships must be taken along with Rutacece), nor is the surface at all pustulate- or tuberculate-glandular as in Thamnosma. But in the petals, and especially in the sepals and minute bracts of the inflo- rescence, I discern evident traces of the Rutaceous oil-glands. Faint and few though they be, they suffice to confirm the affinity.

There are four of these spartioid green-barked and raainl}'^ leafless shrubs in the dry Arizonian region. Thamnosma montanum, Torr.,

* Adansonia, x. 18, & Hist, des Plantes, vi. 43, 1875.

OF ARTS AND SCIENCES. 161

which is a jjenuine Ratacea ; Holacantha Emoryi, Gray, an undoubted Siinaruhacea ; Koeberlinia spinosa, Zucc, which has been referred to the same order, but is more anomalous ; and tinally Caiiotia holacantha.^ which, if I mistake not, must take its place among the typical Rutacece, notwithstanding some anomalies.

The pollen of Canotia, as pointed out to me by Prof. Rothrock, who has supplied the best flowering specimens we possess, is exactly repre- sented by Sach's figure of that of Epilobium, viz., that in his Lehrbuch, fiir. 349.

a

SYMPETALEIA, Nov. Gen. Loasaceariim.

Calycis tubus globoso-obconicus ; limbus o-partitus, lobis tubo sequilongis. Corolla (alte gamopetala !) hypocraterimorpha ; tubo elongato subclavato intus infra medium piloso-annulato ; limbo 5-par- tito, lobis rotundatis testivatione imbricatis. Stamina circiter 25, corollte tubo sub fauce ant inordinate ant 5-seriatim inserta : fila- menta brevissima, tenuia : antherse subreniformes, uniloculares, bival- ves. Ovarium uniloculare : stylus filiformis : stigmata 5, brevia, conniventia. Ovula indefinite plurima, placentis 5 parietalibus in- serta. Capsula subglobosa, apice tantum dehiscens. Semina per- plurima, oblonga ; testa tenui conformi oblique striato-costulata. Embryo in albumine parco granuloso axilis, rectus, oblongus ; cotyle- donibus brevibns.

Sympetaleia aurea. Herba annua, humilis, Eucnidis facie, vis- coso-hirsutala et setis urentibus Itevibus hispida ; foliis longe-petiolatis rotundato-cordatis crenatis vel 3-o-lobatis ; pedunculis termiualibus et supra-axillaribus, fructiferis elongandis recurvis ; corolla aurea semi- poUicari. — Pulpito Point, Lower California, Dr. Thomas H. Streets, U. S. N. Coll. in February, 1875 ?

In this we have the anomaly of a Loasaceous plant with a truly gamopetalous corolla! In Eucnide of Zuccarini, — a genus which had been merged in Mentzella, but which Mr. Watson, in the Botany of California, has properly reinstated, — the petals are united at the very base into a ring, which bears the stamens. Here they are combined into a long tube, and even to the base of the spreading limb, and the stamens are borne in and below the throat. The imbricated aestivation of the corolla is shared by Eucnide, Mentzelia, &c. ; but the one-celled anthers, of the Malvaceous pattern, are peculiar. The tube of the calyx is completely adnate to the ovary, which is crowned by a flat disk ; and the corolla is epigynous. The habit of the plant is wholly

VOL. XII. (n. S. IV.) 11

162 PROCEEDINGS OF THE ABIERICAN ACADEMY

that of J^ucnide. The name choseu for the genus expresses its most striking character, viz., the union of the petals.*

LEMMONIA, Nov. Gen. Hydrojphyllacearum.

Corolla brevi-campanulata, sepala angusto-linearia hand superans, 5-loba, intus nuda. Stamina brevia, tubo corollte brevissimo a^qualiter inserta : filamenta siibulata. ad insertionem subito dilatata, quasi ap- pendiculata : antherce cordato-didjmEe. Discus obscurus. Ovarium ovoideum, pilosum, biloculare, stylis 2 brevibus superatum : stigmata capitellata. Ovula in loculis binis, superposita, obovata, auatropa. Capsula ovoidea, retusa, 4-sperma, bivalvis ; valvis membranaceis semisepta angusta firmiora ferentihus. Semina ratione capsulae magna, obovata, grosse rariter ruguloso-impressa ; testa tenui ca^terum licvi. Embryo cylindricus, rectus, albumine carnoso paullo brevier.

Lemmonia Californica. Herbula annua, depressa, dichotoma, sericeo-canescens ; foliis alternis basi apiceque ramorum confertis spathu- latis integerrimis ; floribus cymoso-congestis et in dichotomis infimis solitariis subsessilibus ; sepalis albo-villosis angustissirais apice noa latioribus, fructiferis (lineas 2 longis) capsulam superantibus ; corolla lineam longa alba sen albida. — San Bernardino Co., California, on Bear Valley Creek, on the head waters of the Mohave River, May, 1876, J. G. Lemmon. This interesting little plant, which was sent to me in a letter by Mr. Lemmon at the time of its discovery, was passed over by me as a Coldenia § Tiquiliopsis, which it resembles in aspect and especially in mode of growth. But it proves to be the type of a new geiuis, somewhat related to Draperia among the Pliacelieoe, yet belonging jjroperly to the Namece. It is distinguished from Nama by the short campanulate corolla and correspondingly short styles and subu- late filaments (the latter dilated and thickened at the very insertion in such manner as to form a sort of annulus to the corolla-tube), and

* In the small but interesting collection of plants of Lower California, made b}' the discoverer of this genus, occurs a new Hemizotiia, the characters of which are here appended : —

Hemizonia Streetsii. § Hartmannin, H. angnstifolkB et corijmhosce sat affinis, humilis, ramosa e radice annua, pubescens, eglandulosa; foliis linearibus nunc integerrimis nunc inciso-4-5-dentatis ; capitulis ramos terminantibus brevi- pedunculatis ; ligulis ultra 12 biseriatis elongatis oblongo-spathulatis, tubo brevi glanduloso ; paleis receptaculi convexo-conici circa flores disci plurimos steriles basi connatis ; pappi paleis fl. disci 8-10 lineari-lanceolatis parum denticulatis corolla paullo brevioribus ; acheniis radii Isevibus. — San Benito Island, Lower California, Dr. Thomas H. Streets.

OF ARTS AND SCIENCES. 163

by the single pair of ovules to each cell, forming large seeds. The latter are very like those of Xama demissa and of Conanthus. As to PhaceUa, which might be thought polymorphous enough to include almost any plant of this sort, even if we disregard the technical char- acter of the distinct styles, yet the geminate ovules and seeds in this plant are characteristic, being superposed, while those of Phacelia, when reduced to single pairs, are collateral.

Of late years I have had frequent occasion to associate the name of Mr. J, G. Lemmon with species of his own discovery ; and I seize with satisfaction the present opportunity of further commemorating the services of a most ardent and successful explorer of the Siena Nevada region, by naming in his honor this interesting new genus which he alone has met with. By the specific name, Californica, I indicate the principal field of Mr. Lemmon's arduous explorations.

ECHINOSPERMUM, Sect. Echinoglochin.

Nuculfe immargiuatse, ovato-trigonse, dorso (medio carinulato) undi- que inordinate aculeolatoe, aculeis tota longitudine setulis retrorsis armatis ; areola prope basim ovata. Corollas lobi convoluto-imbricati. Pedicelli fructiferi erecti. Calyx fructifer patens, nee reflexus.

ECHINOSPERMUM Greenei. EritHcMo fulvo sat similis, iiltra- spithamoeum, e radice annua laxe ramosum, pilis albidis striguloso- pubescens ; foliis linearibus obtusis ; racemis solitariis geminisve laxiusculis hie inde (basi prtesertim) folioso-bracteatis ; calyce fulvo- sericeo-hirsuto ; lobis oblongo-Iinearibus obtusis corollam albam sub- sequantibus ; nuculis (sesquilineam lougis) calyce brevioribus inter aculeas sparsas teretes {^—\ lineam longas) tuberculato-scabris intus acute carinatis. — About Yreka, Siskiyou Co., in the northern part of California, 1876, E. L. Greene. An additional and singular link between Echinospermum and Eritrichlum, but technically belonging to the former, if not worthy of generic distinction ; remarkable for having the prickles glochidiately barbed not merely at the apex, but for their whole length, and not at all arranged in lateral ranks.

ECIIIDIOCARYA, Gray, char, reformatum.

Calyx o-partitus ; segmentis sub fructu parum apertis. Corolla rotato-hypocraterimorpha ; tubo calycem suba^quante lobis rotundatis breviore, plicis faucialibus pi. m. intrusis. Filamenta brevissima medio tubo inserta : antherge oblonga?, inclusee. Stylus brevis : stigma capi- tatum. Nuculae ovato-trigonse, obliquie, cristulato-rugosas, dorso ven- treque carinatse, in stipitibus crassis aut discretis aut per paria coalitis

164 PROCEEDINGS OF THE AMERICAN ACADEMY

(areolis pi. m. cavis gynobasin late conicara claudentibus) incurvo- adscendentibus. — Herbaj annuaj, ditfusaj, Eritrichii sect. Plagiohothri- dis facie ; foliis omnibus alternis ; floribus parvulis albis ; pube hirsuta. — Gray in Benth. & Hook. Gen. ii. 854, & Proc. Am. Acad. xi. 89.

Two species are now known, of very similar aspect ; and it may now be said of the senus that it should stand between Eritrichium and Antiphytum.

EcHiDiocARYA Artzonica, Gray, 1. c. Corolla fauce plicis mini- mis fere evanidis parum constricta ; nuculis parce cristato-muricatis apice compresso-attenuatis basi productis in stipites crassos iisque tsqui- longos inferne connatos, areola (paris) excavata maxima cava. — This species was founded on a specimen collected by Dr. Smart, of such peculiar character of fruit that it might have been thought to be abnormal. But it is now confirmed by additional specimens, collected in March of this year, near Tucson, Arizona, by my indefatigable and sharp-sighted correspondent. Rev. E. L. Greene.* It is also confirmed essentially, and the character modified, by the detection of a second species, in which, however, each nutlet has a wholly separate stipe. This species may be named

EcHiDioCARYA Californica. Corolla majore (lobis rotundatis lineas circiter 2 longis) fauce plicis validis puberulis clausa ; nuculis minoribus (lineam longis) minus acutatis dorso rugoso-alveolatis (rugis acutis echinulatis), stipitibus bi-evibus compressis angulo ventrali supra basim ortis discretis, areola carunculiformi parvula concava. — South-eastern California, in San Bernardino Co., 1876, Parry and Lemmon.

LEPTOGLOSSIS, Benth., subgenus Brachtglossis.

Corolla plane hypocraterimorpha ; tubo filiformi sub limbo rotato in faucem campanulatam brevem stamina claudentem subito modiceque ampliato. Anther* fertiles 4, superiores 2-3-plo minores : filamenta quinta ananthera. Ovarium baud stipitatum, disco tenuiter cupulato subtensum. Stylus sub stigmate angustiuscule bilobo bialatus. Semina {L. Texance) subreniformia, grosse corrugato-rugosa. Embryo in al- bumine earnoso sublncurvus. — Herbaj Texano-Mexicante, humiles, e radice perenni diffusa^ ; floribus majusculis ut videtur albis.

Leptoglossis Texana. Multicaulis e basi firma ut videtur suf- fi'utesceute, viscido-pubescens : foliis spathulato-ovalibus vel oblongis

* At the same station Mr. Greene likewise detected the most singular of all our Borratjinacfv, viz. H(irjia<ioneHa Palincri, before known only from Guada- lupe Island, Lower California.

OF ARTS AND SCIENCES. 165

acutis })lerumque in petioluin brevissimum marginatum attenuatis : calyce iufuudibuliformi-Ciimpanulato pedicello ajqiiilongo vel breviore 5-deutato, dentibus latis acutiusculis ; stigmatis lobis spathulatis deor- snm in apicem styli alato-decurrentibus. — Nierembergia {Leptoglossis) viscosa, & BrowalUa (Leptoylossis) Texana, Torr. Bot, Mex. Bound. 155, 156. — Western Texas, AVright, Bigelow. Adjacent Mexico, at San Carlos, Berlandier, no. 3194. The two names above-cited refer to the same plant. It was probably intended that the hrst should be cancelled.

Leptoglossis Coulteri. Puberula ; caulibus debilibus laxis ; foliis ovatis oblongisve tenuiter petiolatis ; pedicellis longioribus ; calycis lobis triangulari-lanceolatis tubo turbinato cequilongis ; corollas fauce subgibbosa : stylo sub stigmatis lobis subito latissirae alato. — Mexico, coll. Coulter, no. 1346.

In habit and foliage these two plants are not unlike Bouchetia, a genus established by Benthara and Hooker upon one of DeCandolle's two species. The corolla is that of Nierembergia, except that the limb is even flatter, or completely rotate, and the stamens are included in a short and abrupt but small faucial enlargement of the very summit of the tube. The five filaments are all short, not far from equal in length ; the posterior destitute of anther ; the upper anthers small, but polliniferous ; the lower pair with far larger fertile anthers. These characters generally accord with Leptoglossis, Beuth., except ia the shortness and comparative small ness of the throat, wliich in true Leptoglossis is tubular-funnelform and continued downward for con- siderable distance, thus giving the filaments greater length and lowness of insertion. In the style, these plants partake of the peculiar charac- ter of the related genus Reyesia, Clos {Fteroglossis, INIiers, which I know only from the two published figures), except that the stigma is manifestly two-lobed. The scarious-membranaceous wing, which is decurrent from these lobes down the apex of the style, was overlooked by Dr. Torrey in our scanty flowers of the Texan species. Its breadth on either side is not quite equal to the length of the thickish stigma lobe. But in the allied Mexican species the whole wing is much broader, and quadrate or slightly cordate, not flabelliform-obcordate as in Reyesia. The latter genus, of a single species, seems to be pretty well marked in habit, the complete absence of the fifth stamen, &c. But the two plants here described, notwithstanding their resemblance to Nierembergia in general form of the corolla and to Reyesia in the winged apex of the style, are probably best disposed of under a sub- genus of Leptoglossis.

1G6 PROCEEDINGS OF THE AMERICAN ACADEMY

XV.

OBSERVATIONES LICHENOLOGIC^, No. 4. OBSERVATIONS ON NORTH AMERICAN AND OTHER LICHENS.

By Edward Tuckerman, M.A.

(Continued from Vol. VI. p. 287.)

Read May 29, 1877.

Pyxine. The black hypothecium of Physcia picta distinguishes it from the rest of the geuus, and suggests an association with Pyxine ; to which, indeed, this Physcia is in other respects significantly similar. Pyxine, thus enlarged, falls into two sections : —

1. DiRiNARiA. Apothecia scutellgeform. Thallus normally white within, P. picta (S w.). — The species should probably include Parmelia conflaens (Fr.) united by Nylander with the earlier P. cegialita, Ach. : at least no difference seems to be noted. — P. picta occurs now safi'rou- colored within (v. erytkrocardia, Tuckerm. in AYright Lich. Guh. n. 94) like Physcia ohscura ; but also probably to be compared in this respect with Pyxine coccinea, M. & V. d. B., of the next section.

2. Pyxine proper. Apothecia (similar at first, in a tropical form, to those of the first section, but finally) blackening all over and leci- deoid. Thallus soon more or less yellowish within. P. cocoes (Sw.) — The other supposed species of this section are scarcely well defined. P. cocoes V. Meissneri {P. 3Ieissneri of these Obs. 1, in Proc. Acad. Amer. 4, p. 400) might indeed often be taken, and was taken by Meissner, for a Physcia ; but the margin of the apothecium soon black- ens, when tlie lichen is ill distinguishable from the oi'iginal Lichen Cocoes (Sw. Lich. Amer. t. 2). — Another of the more delicate tropical exhibitions of Pyxine is marked by the reticulate wrinkling of the upper surface {P. retirugella Nyl. Lich. exot.) but otherwise is close enough to P. Cocoes. — From this may well seem more separable the larger lichen, extending far northward, which furnished Fries the type of the genus (v. sorediata, Tuckerm. 1. c), but this differs only in size, and not always in that respect, from forms easily included in P. Cocoes.

OF ARTS AND SCIENCES. 167

— The larger form just named is not, however, confined to the north, and exhibits in the tropics a peculiar luxuriance in quadrilocular spores (v. Esclnceileri, Mihi ; given in Wright Lick. Cub. n. 94, iu part) which renders necessary a modification of the genus-character, though the liciien in question (like Physcia obscurascens, Nyl. Syti., as com- jjared with Phijscia obscara) have little claim to be reckoned a species. And, lastly, it may be said that Pyxine coccinen, M. & V. d. B. [Lic/i. Jav. p. 40), which is distinguished, like the last variety, from the var, sorediata by rather larger and quadrilocular spores, seems scarcely otherwise to differ from this, but as P. picta, v. erythrocardia, from the type of that species, or, as Physcia obscura, v. endochrysea, Ham p. (the oldest name of a repeatedly named anamorphous condition) when the medullary layer has become red from the same when as yet it is only yellow. Systematic iXatural History is so much a matter of opin- ion, that it may sometimes seem difficult, at this day, to fully assert its position in the face of more purely objective science : surely, then, all those who love the study of the system will desire that the term " species " should express something worth knowing ; that its value should be enforced and extended rather than diminished and frittered away.

U-MBiLiCARiA Caroliniana, sp. nov.: thallo membranaceo Isevigato papuloso rotundato-lobato mox polyphyllo complicatoque olivaceo-fusco, subtus lacunoso papillato-granulato atro, fibrillis paucis hinc inde ob- sito ; apotheciis subelevatis mox plicatis deinque papillato-ijroliferis. Sporte (2""^?) ellipsoidea3, muriformi- multiloculares, fuscfe, longit. 0,()30-iO'"™-, crassit. 0,020-23"""-. — U. mammulata, Tuckerm. Syn.N.E, p. 69, non A(A\.Jide Nyl. /. infra cit. — Rocks, Grandfather Mountain, N. Carolina, M. A. Curtis. High mountains of N. Carolina, S. B. BucMey. A well-marked Umbilicaria, but the material before me for its illustration is small. The plant was pretty confidently referred, at the place cited above, to the North American Gyrophora -mammulata, Ach. Syn., both from the diagnosis and the name ; and this judgment seemed to be confirmed by my notes (made in 1850) on a specimen then preserved in the museum of the Royal Society of Upsal. But Dr. Ny- lander {Lich. Scand. p. 115) says distinctly, that Acharius's lichen is " spodochroa, apotheciis non rite evolutis." Dr. T. H. Fries also refers it {Lich. Scand. p. 154) to '■'■ spodoch-oa, rhizinis erohitis vel {maxi- mam partem) in tubercula nigra ryiutafis ; " and it is evident that neither of these references is to the North Carolina plant. U. dictyiza, Nyl. {Flora Itatisb. 1869, p. 388) of the same section of the genus as the lichen above described, is, according to Stizenberger {Index Lich. Hy-

168 PROCEEDINGS OF THE AMERICAN ACADEMY

perh., p. 22) from Newfoundland ; and no description of it is known to me.

Sticta Hallii, sp. nov. : tliallo coi-iaceo reticulato-celluloso snbtiliter rimuloso-granulato sparsimqiie villosiusculo cinereo-glaucescente, laciniis rotundatis subintegris, subtus venoso-costato tomentoso maculis pallidi- oribus nudis notato ; apotheciis sparsis (latit. 2-3 millim.) sessilibus, excipulo villoso integre marginato, disro rufo-fusco. Sporae naviculares, biloculares, fnscae, loiigit. 0,023-36"'™-, cra^sit. 0,009-14"'™-. — Trunks, Oregon, E. Hall, 1871. Of the stock of S. scrobicidata, and closely approaching this species, from which it yet differs in its more or less villous upper side, its veiny under side, its villous apothecia, and espe- cially in its brown, always bilocular spores, which are not reconcilable with those of the other. Some of the specimens show indications of the peculiar sorediation of S. ^scrohiculata, — a feature characteristical also in S. anihraspis, Ach., of the same region. The lichen differs from the older species perhaps less in the thallus, than S. Oregana {Mihi in Bull. Torr. Bot. Club, April, 1874) from S. piihnonaria ; but more in the spores. It is dedicated to the discoverer, my friendly corre- spondent, P^lihu Hall.

Erioderma velligerum, sub-sp. nov. : thallo imbricato cinera- scente, lobis adscendentibus rotundatis sinuato-incisis margine subcrispis dense hirsutis, subtus sulphureo ; apotheciis (2-4 millim, latis) marginali- bus extus hirsutis, disco fuscescente. SponB octonaj rotundato-ellipsoi- dete, simplices, limbata;, longit. 0,009-1 G"""-, crassit. 0,008- 10™"'-, leviter in thecis infuscatOB dein incolores. — Shores of the Straits of Magellan, Mev.Dr. Thomas Hill (Hassler exp. 1872). Not well comparable with such species as E. polycarpum and E. Wrightii, which exhibit the nor- mal Peltigeriue frond, but differing from that exactly as some imbricated and crisped forms of Peltigera mfescens. The hirsute upper surface and sulphur-colored under side, as well as the habit of growth, distinguish the lichen from what I have seen of Erioderma Chilense, but the last is very near, and said by Montague to be also imbricate, as it has simi- lar though more rounded spores. I cannot but still consider this little group as belonging to the Peltigerei.

Pannaria symptychia, sp. nov. : thallo foliaceo membranaceo-car- tilagineo ca\spitoso-polyphyllo livido-fnscescente, lobis sinuato-repandis flexuosis complicatis subtus nudis fuscis ; hypothallo obsoleto ; a|)0the- ciis (latit. c. 1""") biatorinis sessilibus, margine tenui integerrimo fusco discum convexum nigrum opacum cingente. Sporre octonte, ellipsoidefe, simplices, incolores, longit. 0,009-16"'™-, crassit. 0,007-10™'"-, paraphysi- bu.o incrassatulis distinctis. — On rocks (apparently) island of Juan Fer-

OF ARTS AND SCIENCES. 169

nanrlez, Rev. T. Hill (Hassler exp. 1872). Thallus with something of the aspect of an Endocarpon not remote from E. miniatum v. aquuti- cum, Schjer., but the internal structure of Pannaria § Coccocarpia. Collogonidia disposed in short chains. Hymeneal gelatine becoming first blue, and then wine-red with iodine. I cannot compare the spe- cies witli any other. Spermogones have not occurred.

Paxxakia Soxomensis, sp. nov. : tliallo ^Jarvulo radiante olivaceo, laciniis linearibus ramosis striatis, centralibus teretiusculis dein intrica- tis, periphericis magis dilatatis flabellatisque dichotomo-multifidis, subtus albis uudis hypothallo obsolete ; apotheciis minutis (0,3-0,4 millim. latis) lecanorinis, margine iutegro dein excluso, disco e rufo-fusco nigricante. Sporte fusiformes, curvuh^, simplices, incolores, longit. 0,020-33"""-, crassit. 0,002-3'"*- Hypothecium pallidum. Paraphyses dein lax£e. — Rocks, Sonoma, and also in the Yosemite Valley, Cali- fornia, Dr. H. N. Bolander. Interior of the thallus compact ; of elon- gated cells. Collogonidia solitary or concatenate; reaching 0,018""°' in length by 0,009"""' in width. Spores fusiform in the sense of Koerb. Syst. t. 3, f. 5 ; and they might be called short-acicular. Belongs to the same group with P. Jlabellosa (Ohs. Lich. 1. c. 5, p. 401) and P. Petersii ( Gen. Lich. \). 54). The resemblance of the interior structure of P. jlabellosa to that of the lichen before us has been well exhibited bv Schwendener {Erijrt. z. Gonidien-frage, Flora Ratisb. 1872, p. 227, t. 4) in the infertile Yosemite specimens sent to him as " Pannarice affinis." It appears quite impossible to remove these plants from Pan- naria ; or to continue to keep Pterygium, Nyl. apart from them in genus.

Paxx'aria stenophtlla, sp. nov. : thallo orbicular! zonatim ceu' trifufo olivaceo, laciniis tereti-compressiusculis, centro squamuloso-dirai- nutis delabentibus, ambitu radiantibus ramosis, subtus pallidis nudis hypothallo obsoleto ; apotheciis lecanorinis perminutis (latit. 0,2-0,3 millim.) disco fusco margine tenui dein disparente. Sporge ex ellip- soideo oblongaj, sa^pe curvul^, biloculares, longit. 0,012-20"""-, crassit 0.003-5"""- — Lime rocks, Moulton, Alabama, Hon. T. M.Peters, 1874. Thallus from a quarter to little more than half an inch in diameter. Structure of the interior of the thallus as in the last species ; collogo- nidia in chains; at length 0,012-20"""- long, and 0,010-12 """thick. The lichen grows with and often commingled with P. Petersii, from which it is readily distinguishable by its smaller size, lighter color both of thallus and fruit and terete lobes. P. Sonomensis is nearer, but exhibits a different habit of growth, and the spores are quite irrecon- cilable with those of the Alabama lichen.

170 PROCEEDINGS OF THE AMERICAN ACADEMY

Synalissa melambola, sp. nov. : thallo effuso rimoso-areolato nigro, areolis planiusculis (latit. deiii plusquam 1 millim.) stipitato- elevatis polycarpis ; apotheciis (0,1-0,3 millim. latis) iunatis lecanoriuis disco subpapillato concolore margiiiem teiiuem persistentem demum superante. SporaB octonaj, ellipsoideas, simplices, incolores, loiigit. 0,010-12"""-, crassit. 0,005-8"""-; paraphysibus omnino conglutinatis. — Lime rocks, Alabama, Ho7i. T. M. Peters. Thallus cellulose ; the col- logouidia solitary. The reaction of the hymeneal gelatine with iodine is blue. Plant noticeable for its large, flattish, black areoles, which the lens shows to contain from two to six or more very minute but quite regular apothecia.

Synalissa viridi-rufa, sp. nov. : thallo effuso granuloso mox rimu- loso-diffracto fusco-viridi ; apotheciis (latit. 0,2-0,4 millim., visis) leca- noriuis adiiatis subplanis, disco rufo, margine subpersistente. Sporae octona;, ellipsoideai, Hmbatce, incolores, longit. 0,016-18""-, crassit. 0,008-1 0'""'- ; paraphyses conglutiuatte. — Lime rocks, Texas, G. Wright. Structure not very different from that of the last ; rounded, green cel- lules, with mostly solitary collogonidia, which reach a diameter of 12-15 mic. The reaction with iodine also as in the last. The lichen is marked among our species of this group by its rather brighter colors.

Ojiphalaria kansana, sp. nov. : thallo pulvinato coriaceo-cartila- gineo atro e lobulis stipitatis erectis clavatis vel sublobatis vel fructu dilatato pileatis ; apotheciis (0,5-0,8 millim. latis) terminalibus con- coloribus mox convexis margine disparente. Sporse — 12-"'^ in thecis ventricosis, ex ellipsoideo dein ovoideo-oblongte, medioque constrictie, simplices (tenuiter demum uniseptatae ?) incolores, longit. 0,005-8™™-, crassit. 0,003-4"'™-, paraphysibus bene distinctis. — On lime rocks. Chase County, Kansas, E. Hall, 1871. Reaction with iodine, blue. Collo- gonidia mostly collected into small clusters of 3-5, amidst anastomosing filaments, which alone occupy the centre of the thallus : the structure of 0. corallodes (Mass.) Nyl., with which the Kansas lichen appears best to agree generally. The two species differ from Omphalaria PROPER, as here understood {Gen. Lich. p. 81) with umbilicate thallus, in forming cushions of stalked lobes, which become more or less lobu- late above. However ill exhibited this lobate or foliaceous character, it seems enough to give these plants a higher place in the system than that of Synalissa synnphorea. The Kansas lichen is, so far as seen, a smaller species than the European with which it is above compared, and less evidently foliaceous. It is characterized at sight by its ele- vated convex apothecia, looking like nail-heads.

Leptogiuji rivale, sp. nov. : thallo membranaceo microphyllino

OF ARTS AND SCIENCES. 171

plumbeo, lobis imbricatis linearibus plauis repandis ; apotheciis (ostiolis indicatis) iiniuersis. Sporje octonaj, e fusiformi ovoide^, biloculares, incolores, loiigit. 0,01 6-23'""-, crassit. OjOOo-S"""-. Paraphyses parcse. — " On small pebbles in the bottom of a clear brook around the Big Trees, Mariposa," California (growing with and on Hydrothyria, Russ.) Dr. Bolatider. Lobes scarcely exceeding 0,5 millim. in width. Texture of the thallus parenchymatous throughout ; an outer row of polygonous cells, distiusfuishable from the rounder and looser cells of the intei-ior, indicating the cortex of the present genus. Collogonidia solitary, or in very short chains. There is little in the lichen to remind one of the equivocal Gollema rivulare, Ach., of Sweden, which yet agrees with the other in the very interesting points of an entirely cellulose texture and an aquatic habitat. The Californian plant was supposed to be infertile ; but my friend Dr. Schweudener met accidentally with an immersed apothecium in a section of the thallus which he was examining, and I have since found such fruits to be indicated externally by a distinct ostiolar margin. Whether there is ever any further de- velopment or emergence of this apothecium is unknown. The small material before me 2:ave no indication of lichenine with iodine.

Placodium galactophyllum, sp. nov. : thallo crustaceo-adnato areolato-squamuloso ambitu lobato, farinoso lacteo, detrito fulvo ; apotheciis (latit. 0,5-0,9 millim.) zeorinis sessilibus plauis disco auran- tiaco tenuiter marginato. Sporte octonte, polari-biloculares, incolores, longit. 0,008-1 4"""-, crassit. 0,00-4-6"'"'-. Tuckerm. Gen. Lich. p. 108. — On lime rocks, Chase Co., Kansas, E. Hall, 1871. A distinctly lobed lichen with the habit of Lecanora muralis v. albo-pulverulenta, Schier. {Lich. Helv. n. 334) and differing in this respect from even the best condition of the European P. erythrocarpium ; the spores of which are also larger, and not rarely measure, in my specimens Vn^- ^^^- Apo- thecium of our lichen distinctly lecanorine, with marginate disk.

Placodiuji FERRUGIN0SU5I, sp. nov. : thallo crustaceo rimoso-areo- lato aurantiaco, areolis subinde lobulatis, hypothallo nigro ; apotheciis (latit. 0,6-0,9 millim.) biatorinis sessilibus ferrugineis (nigricantibusque) maro-ine demum flexuoso. SporiE octonas, polari-biloculares, incolores, lono-it. 0,016-2r"'"-, crassit. 0,006-9"""-. — Volcanic rocks, Island of Chi- loe, Chili, Dr. T. Hill (Hassler exp. 1872). Almost P. cinnaharinum, as respects the thallus, but with the apothecia almost of P.ferrugineum.

Placodium ferruginecm (Huds.) Hepp, * miniaceum ; apotheciis miniatis. — On buslies, Cape of Good Hope, C. Wright. The appressed apothecia differing only, but remarkably, iu color, from Cape specimens of P. ferruginemn (Drege in herb. Sonder ; Wright), which are uudis- tiniruishable from the northern lichen.

172 PROCEEDINGS OP THE AMERICAN ACADEBIY

Placodium atroalbum ; tliallo tenui granuloso dein 'et rimoso- areolato luteolo-fuscescente ; apotheciis (latit. c. 0,3-0,5 mm.) adnatis zeorinis, margiiie thalliuo tenui demisso integro albo discum margina- tum nigi-um nudum cingente, intus incoloribus. Sporoe octonte, ellip- soidea3, polari-biloculares sporobl. approximatis, lougit. 0,014-23"""-, crassit. 0,005-9"""-, paraphysibus filiformibus fusco-capitulatis demum dis- tinctis articulatisque. — On cretaceous sandstone and chalcedony, North Platte, Rocky Mountains, Dr. Hayden. Lime rocks, Utah, Mr. Lapham. Of the stock of P. variahile (Pers.) Nyl., which occurs with well- marked distinctness from this in the same region ; and closely asso- ciable with the P. Agardhianum of Anz. Lich. Langob. n. 37. But our lichen is scarcely as well comparable with the P. Agardhianum of Hepp {Lich. exs. n. 407), and differs still more from the specimen before me of Pyrenodesmia Agardhiana, Mass. (Arn. in herb. Koerb.)^ which is wholly lecideoid. This last is represented here by a lichen of the Alabama lime rocks {Judge Peters). If all these be to be taken for states of the same variable species, our Rocky Mountain lichen above described is, with little doubt, another. The polar type is not easily made out in the spores of the latter ; which, but for the other structure of the hymenium, might be supposed rather a Lecanora akin to L. erysibe (Ach.), Nyl. There are no reactions of the thallus with potash or chloride of lime.

Lkcanora. Semitensis, sub-sp. nov. : thallo e squamulis glebosis stramiueis mox crenato-lobatis subinde hypothallo nigro marginatis ; apotheciis (0""" , 7-1"""- latis) appressis plano-convexis tumentibusque congestis, disco livido-fuscescente albido-pruinoso, margine demum sub- granulato vel excluso. Hypothecium incolor. Sporoe octonoe ellip- soide£E simplices incolores, longit. 0,011-10"""-, crassit. 0.005-6"™-.— Granitic rocks, Yosemite Valley, California, Dr. Bolander. Clearly a member of the Saxicola group, and very close to L. saxicola v. dif- fracta, from which (largely exhibited on the Californian rocks) the present differs in its scaly thallus, which is not radiant, and the ultimate development of its fruit.

Lecanora glaucovirens, sp. nov. : thallo crustaceo orbicular! verruculoso-granulato viridi-glaucescente versus ambitum albido, hypo- thallo incolore; apotheciis (latit. 0'""'-, 7-1"""-) appressis, disco mox convexo e livido-fusco nigrescente, margine integerrimo. Hypothecium pallidum. Sporaj octonaj, ellipsoideoe, simplices, incolores, longit. 0,014-17'""-, crassit. 0,006-9, paraphysibus conglutinatis. Spermatia acicularia arcuata.

On bark, Galapagos Islands, South America, Rev. T. Hill (Hassler

OF ARTS AND SCIENCES. 173

Exp.). Of the stock of L. suhfasca, but with rather the habit of conditions of Rinodina sophodes. Patches about an inch in diameter.

Lecanora dentilabra, sp. nov. : thallo crustaceo tenui areolato- verrucoso glaucescente ; apotheciis (hitit. 0"""-, 5-0"""-, 9) adnatis, mar- gine tumidulo mox fisso-subcrenato, disco fusco oi)aco jilano vel demum tumente niarginemque exchidente. Hypothecium incolor. Spor« octonie, ellipsoidese, simplices, incolores, longit. 0,012-25"""-, crassit. 0,010-16"™', paraphysibus conglutinatis.

On bark, Island of Chiloe, Chili, and at Sandy Point, Straits of Ma- gellan, Rev. T. Hill (Hassler exp.). Without doubt also of the sub- fusca stock, the apothecia being characterized much as those of the rupicoline L. ccesio-alba, Koerb., of Europe.

Lecanora orosthea (Sm. L. expcdlens, Ach.) var. Japonica ; apotheciis (latit. 2-3 millim.) elevato-sessilibus flexuoso-lobatis ; sporis longit. 0,020-23™""-, crassit. 0,008-14™™-. — On beech-trunks in the mountains near Hakodadi. Japan, C. Wright (U. S. N. Pac. Exp.). Closely associable with our luxuriant North American condition of L. orosthea, but differs in the development of the apothecia and the larger spores, which I have only seen in 4'- and 6'-, in the thekes. L. orosthea perhaps deserves the rank of a sub-species under L. varia.

Lecanora Franciscana ; thallo verruculoso-granuloso albo-cine- rascente ; apotheciis (latit. 0,7-1,5 mm.) pseudo-biatorinis liberis e fusco-rufo nigris mox couvexis turgidisque marginem concolorem ex- cludentibus. Hypothecium subduplex, superius incolor, inferius cras- siusque fuscescens ; strato gonimo impositum. Spora3 octonje, ex ellipsoideo mox oblongaj, biloculares, incolores, longit. 0,013-23™™-, crassit. 0,003-5™™-, paraphysibus coalitis. — On sandstone, San Fran- cisco, Cal., Dr. Bolander. A sub-species probably of L. erysibe (Ach.) Nyl. Apothecia with the aspect of a Lecidea not very unlike a condi- tion of L. enteroleuca, Ach., of the same rocks, but really biatorine, except that the hypothecium rests on the gonimous layer. The reac- tion of the hymeneal gelatine with iodine is blue.

Rinodina radiata : thallo crustaceo rimoso-areolato ambitu radi- oso-lobato glaucescente, hypothallo nigro ; apotheciis (latit. 0,3-0,7 ram.) imnatis deln emergentibus, disco plauo-convexo tumidove nigro albo- pruinoso, margine thallino integro demum disparente. Hypothecium fusco-nigrum. Sporte octonaj, brevi-ellipsoide^e obtusas, biloculares, fuscce, longit. 0,007-12™™-, crassit. 0,005-7™™', paraphysibus congluti- natis.— Buellia radiata, Mihi in Lich. Calif, p. 25.

b, thallo depauperato hypothallo radiante subfimbriato. Rocks on the coast of California, Bolander. Referred to Buellia at the place

174 PROCEEDINGS OF THE AMERICAN ACADEMY

cited, notwithstanding the now clear thalline border, on account of the black hypotlieciiim, and the evident resemblance to B. albo-atra. But Rinodina makes many approaches to Buellla, and the color of the hypotliecium proves to be an insufficient criterion. Nylander, indeed ( Obs. Pijren. p. 52) has referred BiielUa albo-atra to the group now before us ; the reference being, however, determined by the presence of truly jointed sterigmas. I have been unable myself as yet to find multi-articulate sterigmas in the specimens examined of this species, or of that described above, but what might rather be taken for sub- simple forms of the organ in question occur sometimes with a few swollen joints. As originally observed, this lichen appeared comparable rather, as respects thallus, with such effigurate ones as Lecanora circi- nata; but the best developed plant (San Diego, Herb Willey) has a laciniate circumference like that of Placodium candicans ; while on the other hand depauperate conditions occur with no trace of a lobulate margin.

Rinodina thtsanota, sp. nov. : thallo crustaceo verrucoso ambitu radioso-lobato fusco-olivaceo ; apotheciis (qu. visis 0,5-0,7 mm. latis) lecanorinis sessilibus, margine tumidulo integro discum nigro-fuscum cingente. Hypotliecium pallidum. Spoi'oe octonaj, brevi-elliijsoideae, biloculares, fuscaj, longit. 0,010-14™"'-, crassit. 0,005-6'"'"-.

Rocks, alt. 7,000 feet, in Alpine County, California, /. A. Lapham. Thallus, in the single specimen, differenced much as in R. oreirm. Reaction of the hymeneal gelatine with iodine, blue.

Rinodina mamillana, Tuckerm. Lich. Hawai. in Proceed. Amer. Acad., 7, p. 226, has been collected more recently in the Galapagos Islands, Rev. T. Hill (Hassler exp ). Apothecia of both lichens similar in size (0,3-0,8"™- wide), but the specimens of that from the Galapagos not exhibiting the peculiar protuberance and plaiting of the disk which suggested the specific name, and their thalline margin at length black- ening. Hypothecium in both blackish-brown. Spores, 0,012-20"""- long and 0,005-10"""- thick ; the paraphyses at length distinct. Thallus higlier- or sulphur- colored in the South American plant.

Rinodina ochrotis : thallo crustaceo granuloso mox fatiscente furfuraceo albido ; apotheciis (qu. visis circ. 0,5 mm. latis) lecanorinis sessilibus, disco e livido-carneo fuscescente, margine obtuso integro. Hypothecium pallidum. Sporoe parv^e, obtuse ellipsoide«, biloculares, fuscge, diam. 2-3° longiores. — Lecanora, Mihi in Wright Lich. Cub. n. 115.

On charred surfaces of logs, IMonte Verde, Island of Cuba, G. Wright. The description was reserved in hope of other specimens being sent. In the absence of such, I can now add nothing to the above.

OF ARTS AND SCIENCES. 175

RixoDiNA MiLLiARiA, sp. iiov. : tluxllo ci'ustaceo teniii verruculoso viridi-fuscescente ; apotlieciis perminutis (latit. circa 0,2-0,'l: mm.) ad- natis lecanorinis, disco fusco-nigro opaco plano-convexo, margiue tenui integro dein uigricante vel excluso. Hypotlit'cium fusco-nigrum. Spor?e octona?, obtuse ellipsoidea^, biloculares, fiisav, longit. 0,009-1 5"""-, crassit. 0,005-8"""', parapliy!>ibus demum distioctis, fiisco-caiaitulatis.

A common bark-lichen about Boston, and found also at New Bed- ford, H. WiUey ; and in Western New York, Miss Wilson. It is differenced from ordinary R. sophodes v. exigna by its blackened hypo- tbeciura, — a character, in this place, of some interest. The spores occur now in twelves according to Mr. Willey, a variation like the well-known one in the v. exigua (constituting R. jiolyspora, Th. Fr.). But our lichen is also curious as seeming to exiiibit filiform, bowed spermatia (0,012-20"™- long) on simple sterigmas. This obser- vation has been made repeatedly both by Mr. Willey and myself, and we are unable to refer the black, papillteform spermogones and contents in question to any other lichen than the one upon whose thallus they occur, though it appears quite inadmissible, in present knowledge, that they can belong to it.

Pertusaria thamnoplaca, sp. nov. : thallo fruticuloso cartilagineo appresso dichotomo-ramoso albido-fuscescente, ramis subteretibus papil- lato-verrucosis subtus albis fibrillis sparsis concoloribus ; apotheciis de- presso-globosis monothalamis mox papillato-coronatis (latit. dein 1 mm.) ostiolo punctiformi nigro. Sporte octonte, ellipsoidece, simijlices, inco- lores, longit. 0,0o0-72'"'"-, crassit. 0,023-38™™-.

Trunks, ShoU Bay, near the western entrance of the Straits of Ma- gellan, orrowing with and often on the next, Rev. T. Hill (Ilassler exp. 1872). Another illustration of the fruticulose thallus in a properly crus- taceous group ; and more remarkable than either of those described from our own Pacific coast (Lich. Calif, in loc). Thallus (reaching a diameter of more than two inches) closely appressed and affixed by its fibrils to the matrix, dichotomously much branched, either terete or now a little compressed, and in the larger parts almost attaining a thickness of one millimetre. The whole is besprinkled, at length densely, with crowded papillie, which surround the apothecia with one or more coronals, and hide often, to a considerable degree, the branches. Under the micro- scope, the direction of the very minute and confused network of fila- ments which makes up the interior of the thallus is seen to be on the whole longitudinal.

Pertusaria colobina : thallo crustaceo uniformi papillifero, papil- lis dein confertis, centralibusque subelevatis ; apotheciis ab iis P. tham-

176 PROCEEDINGS OF THE AMERICAN ACADEMY

noplacce vix distinguendis nisi sporis minoribus longit. circ. OjOiG-SG""™ , crassit. 0,023-2G™™-.

With the last, at Sholl Bay, and also, on bark, in the Galapagos Is- lands, ^ey. T.Hill (Hassler exp. 1872). The material does not enable me to explain the true relation of this lichen to that immediately pre- ceding. With so much agreement in the fruit, the differences in the tliallus are startling ; while yet specimens of each, well covered with papillae, may be supposed at sight the same.

Pertusaria ambigens : thallo cartilagiueo la3vigato subinde rugoso- veriucoso glaucescente ; apotheciis lecauorinis (latit. 0,6-1,8™"'') sessili- bus vel subelevatis 1-2-tlialamis, margine thallino lacero-subcrenato demum repetito-duplicato discum planum viridi-Ciesium cingente. Sporaj octonce, ellipsoideai, simplices, incolores, 0,01 7-23"""-, longoe, 0,008-1 2"""' crassfe ; paraphysibus capillaribus. Lecanora ambigens, Nyl. Eiium. Gen. Lich. p. 113, and Prodr. Ft. Nov. Granat. p. 40, not.

On trunks, Oregon, at 49° N. lat., Dr. Lyall ; and elsewhere in the same country, E. Hall. The lichen does not differ from a Cape of Good Hope plant {Zeylier in herb. Sonder), also on bark, which is, without doubt, what Nylander has described (Prodr. N. Granat.) irom. the same herbarium. And, so far as appears, it fully agrees also with a rock lichen collected by Mr. AVright at the Cape, and long since de- termined by Nylander as his Lecanora ambigens. The spore-features vary somewhat from the Pertusaria type, and appear to have influ- enced the first describer in excluding the lichen from the genus to which, however, he admits that it perhaps rather belongs. I can en- tertain no doubt of this. Nothing illustrates so well the very peculiar differentiatiou of the apothecia as forms associable more or less closely with Pertusaria velata ; and sjiecimens of P. velata * rnidtijmncta are before me which are hardly, at first sight, distinguishable but by the spores. These apothecia (in the Oregon plant) present at length much the a-p23earance in small of a pile of plates; the margin of the elevated apothecium gaping horizontally into two, three, or more margins. Spores enveloped in a halo in both the American and African lichens. The spores of ours agree very well in size with my measurements of the African {herb. Sonder), but Nylander (1. ( .) gives rather larger figures, or 0,023-30""°- longit. and 0,010-11"^™- crassit.

Pertusaria flavicunda, sp. nov. : thallo cartilagiueo laevigato verrucoso-areolato pallide sulphureo, areolis ambitus radiose subconcre- scentibus; apotheciis depresso-globosis (latit. 1-1,5 mm.) monothalamis, ostiolo mox dilatato hymenium nigricantem pulvere lutuleuto adspersum

OP ARTS AND SCIENCES. 177

exliibente. Sporte 2-3"* in thecis, ellipsoidece, simplices, incolores, 0,060-80"""- longis, 0,040-50"""- crassis.

Kock.-s, San Dietro, Califoinia, Dr. J. G. Cooper ; and received, also, in excellent condition from other collectors (Herb. WiUey).

Pertusaria euglypta, sp. nov. : thallo cartilagineo insculpto- rimoso glauco-cinerascente ; apotheciis sub-globosis (latit. 1-1,8 mm.) pleiotlialamis, circnm ostiola punctiformia nigra depressis. Sjiorae '3- 6"", ellipsoidea;, simplices, incolores, longit. 0,(192-138™"'-, crassit 0,040-60""°-.

Granitic rocks, Cape of Good Hope, C. Wright. Comparable with states of/*, communis, Auct. {pertusa (L.) Ach.), but diifcring in the spores, and in its elegantly sculptured crust, which reminds one of a cuneiform inscription.

Pkrtusaria albinea, sp. nov. : thallo tenui rimuloso-areolato lacteo linei^ nigris decussato ; apotheciis depresso-hemisphajiicis depla- natisque pleiotlialamis (latit. 0,5-0,8 mm.) ostiolis minimis punctiformi- bus nigris. Sporte octonte, ellipsoideae, simplices, incolores, longit. 0,043-58"""-, crassit. 0,023-40"'"'-.

On bark, Galapagos Islands, Rev. T. Hill (Hassler exp. 1872). Dis- tinguishable from P. leioplaca bv habit, and the smalliiess of its parts.

Thelotrema Californiccji, sp. nov. : thallo subtartareo verru- culoso pallide ochroleuco ; apotheciis lecanoroideis (longit. 0,3-0,7 mm.) adnatis sub-planis, excipulo exteriori margine obtuso integerrimo thai- lino discura nigrum velo margine concolore perforato subvestitum in- cludente, demum flexuoso-irregnlaribus stellatis lirellatisqiie. Sporte octon^e, ex ellipsoideo dactyloideae, 4-8-loculares, loculis integris, fuscag, longit. 0,020-30'""-, crassit. 0,005-8"'™-.

On bark, San Diego, California, Dr. E. Palmer (Herb. AVilley). The whole of the interior of the disk is black, without distinguishable proper margin, and the general aspect is that of Lecanora ; but the spores, and the crustaceous veil, whicli is more or less exhibited, appear to associate the lichen with Thelotrema, tliough I know of no species to compare it with. Apothecia now suggesting those of Chiodecton xphce- rale. There is no reaction of the hymeneal gelatine with ioiline; nor of the thalline tissues with liquor potassas or hypochlorite of lime.

PiLOPHORUs acicularis (Ach.) Tuckerm. Gen. p. 146, f. Hallii ; apotheciis elongatis (longit. 2-4 mm., crassit. 0,5 mm. — 1 mm.) pistil- liformibus. — On rocks. Cascade Mountains, Oregon, E. Hall. The apothecia of Pilophorus pass from a globular, often depressed figure, as in f. Fibula, into a slightly conical one, like an elevated skull-cap (jiD.og;), as in the original f. acicularis. And the last is lengthened in the present so as to resemble a pestle. As comjiaied with the other

VOL. XII. (n. S. IV.) 12

178 PROCEEDINGS OF THE AMERICAN ACADEMY

forms, the podetia of this are short and stout, the whole lei)gth scarcely exceeding, in the specimens, thrice that of the longest ajwthecia. Spores of the species, 0,016-23™™- long and 0,007-8"™- thick. — All the known forms of PUophorus fall readily under one species ; there are no satis- factory characters to distinguish them. But it is more difficult to follow Dr. Th. Fries in his recent reference hither {Lich. Scand. p. 55) of one of the two states of his Stereocaidon cereolinum, Monog. Stereoc. p. 40, which is otherwise universally recognized as a Stereocaulon ; and, as he says, is only with extreme difficulty (" cegerrirne,'^ Lich. Scand. 1. c.) distinguishahle from the other form. The "good" figure of Ach. Meth., of the fertile condition of S. cereolus, is not cited in this reference of the plant to PUophorus. It is surprising, if Acharius really had PUophorus fibula in fruit, before him, when he described his Stereoc. cereolus, that he should not at once have recognized the resem- blance of the former to his Cladonia acicularis. Such mistake could hardly occur here, where the PUophorus is scarcely known but as fertile, and the somewhat similar, commonly sterile, often subsimple lichen, with powdery heads, is most readily and often certainly refer- able to the Stereocaulon.*

BiATORA CAULOPHYLLA, sp. nov. : tliallo 6 lobulis stlpitiformi- erectis compressis sursum dilatatis lobatisque griseo-virescentibus in crustam plicatam subinde albo-fai-inosam stipatis ; apotheciis mediocri- bus (dein et 2 mm. latis) margine obtuso mox livescenti-nigro discum planum rufo-fuscum uigrumque cingente. Sporje octonas, ovoideo-ellip- soideae, simplices, incolores, longit. 0,007-13™™-, crassit. 0,004-G™™-, para- physibus conglutinatis. — On rocks, mountains of California, Z)/-. J5c»/an- der. The erect lobes are at length 5-7 mm. long, and, in their widest portions, 2-3 mm. wide. This is a pronounced exhibition in the squa- mulose BiatortB of the extraordinary modification of thallus in Lecidea vesicular is (llotfni.), Ach., and L. coiiglomerata, Ach. As in Lecanora thamnoplaca, Tuckerm. {Gen. Lich. jj. 113) the stipitate lobes of the lichen before us are comparable, in fact, with those of L. 7'iibina, v. complicata (Anz. Lich. Ital. p. 158), the type of which is an almost foliaceous, and in every way distinguished representative of the crusta- ceous thallus. And, as with the LecidecB just named, there is no species to which our Biatora should be referable as a sub-caulescent over- growth. But this is scarcely as clear in the case of somt^ other stipitate- lobate lichens : L. thamnina, noticed in Gen. Lich. p. 1 20, being probably inseparable from luxuriant Californian conditions of L. cerviua b. squa-

* In t])e above cited Gen. Lick. p. 146, note, the spores of the f. robuslus should be said to be 0,016-23°'"- long.

OF ARTS AND SCIENCES. 179

mttlosa, Fr., and Lecidea. canlesrens, Anz. (Lich. Langoh. n. 139) as close, in all respects, to L. sqitalida (Sclileich.) Ach. Curious as it is then, too much stress should perhaps not be laid on the systematic value of the thallus we have been considering,

BiATORA PETRI, sp. nov. : thallo e sqnamis membranaceo-cartila- gineis ex orbiculatft- oblongo-difFormibus undiilato-lobatis subimbricatis glauco-cinerascentibus (fuscescentibus) subtus ambituque asceiidente mox fiiscis ; apotheciis marginalibus sessilibus nitidis (latit. 1-2 mm.) disco subplano rufo (nigro) margine flexuoso nigro demiim excluso. Sporce octonse, ovoideo-ellipsoideae, simplices, incoloi'es, longit. OjOOO-ll""-, crassit. 0,004-o'"™-, paraphysibus coalitis.

On lime and other rocks, growing over mosses, Moulton, Alabama ; Hon. T. M. Peters. The smooth scales at length reticulately rimulose, as common especially in B. globifera (Ach.), Fr. ; but the lichen is readily distinguished from the species named, as from B. Russellli. and B. hiridella of these papers, by the colors, and the thinness of the loosely aopo-reffated thallus.

BiATORA CARNULENTA, sp. nov. : thallo obsoleto ; apotheciis parvis (latit. 0,3-0,6 mm.) adnatis convexis ex albido livescenti-carneolis, mar- gine perquam tenui demisso obscurato vel stei»ius evanido. Hypothe- cium incolor. Sporge octona3, ovoideo-ellipsoideiJe, simplices, incolores, lou'dt. 0,007-12"""-, crassit. OjOOS-o™"-, paraphysibus conglutinatis. — Dead, soft wood in the White Mountains. Found also on the same substrate at Geneseo, N. Y., H. Willey. Reaction of the hymeneal gelatine with iodine, blue.

BiATORA PELiASPis, sp. nov. : thallo tenuissimo albido vel obsoleto ; apotheciis parvis (latit. 0,3-0,6 mm.) sessilibus subplanis, disco livido- fuscescente pruinato, margine tenui nigro disparente. Hypothe- cium fusco-nigrum. Spor* ellipsoideas, simplices, incolores, longit. 0,005-11 mm., crassit. 0,003-5 mm., paraphysibus conglutinatis. — On dead, soft wood, South Carolina, H. W. Ravenel, &c. ; Massachusetts, H. Willey. Very close to this is a minute lichen {B. peliaspi'stes, Mihi herh.) found by me on living hemlock trunks, with leprous-granulose, white thallus ; and on dead, soft wood, without thallus, in the White Mountains, in which the ajiothecia are always naked, and the spores rather smaller (0,005-11 mm. long, and 0.0025-35 mm. thick) and oblong. Both lichens long represented with me the old '' Biatora anomala" of authors. Both exhibit with iodine the same blue re- action.

BiATORA GLATJCONiGRANS, sp. nov. : thallo granuloso giaucescente; apotheciis (latit. 0,2-0,5 mm.) sessilibus mox convexis e livido-fusco

180 PROCEEDINGS OF THE AMERICAN ACADEMY

nigris, margins tenuissimo demisso mox nigricante vel evanido. Hypo- thecium nigrum. Sporae octon£e, ex ellipsoideo oblongae, biloculares, incolores, longit. 0,009-15"""-, crassit. 0,0(»3-4"""-, parapliysihus coalitis. — On the bark of white pine, New Bedford, Mass., Mr. Willey. The well-developed crust, the hypotliecium, and the paraphyses distinguish this from B. lenticulans (Acli.), &c.

BiATORA LiviDO-NiGRrcANS, sp. Hov. : thallo e granulis cartilagi- neis discretis livido-glaucescentibus ; apotheciis minutis (latit. 0,2-0,4 mm.) sessilibus plauis tenuiter marginatis fusco-uigris. Hypoihecium pallidum. S[)or9e octonjB, dactyloideas et oblongte, 4-o-locuhires, inco- lores, longit. 0,015-23"'™-, crassit. 0,003-6"™-, paraphysibus distinctis, capitulatis. — On bark, Sandy Point, Straits of Magellan, Jiev. T. Hill (Hassler exp. 1872). Specnuen a very small one, but the characters sufficient to distingnish the lichen from Lecidea sororiella, Nyl., of New Grenada (Lindig exs. n. 2838) as from the Australian L. Uvido-fusca, Nyl. (Si/n. JV. Caled. p. 42, not.) and L. licido-fuscescens, Nyl., of Brazil {Flora, 1869, p. 122), all of which are taken by their author to relate nearly to Blatora trachona, Flot. With iodine a vinous tint is exhil)ited by the hymeneal gelatine of the antarctic lichen, following a bluish.

Lecidea mamillana, sp. nov. : thallo squamaceo-areolato viridi- glaucescente (cinerascente aut dealbato) areolis mox turgescentibus radiatimque striatulis ambitu sublobatis, discretis vel dein aggregatis ; apotlieciis in areolis innatis centralibus minutis (latit. 0,3-0,7 mm.) plano-convexis nudis margine tenui evanido. Hypothecium fuscum. Sporse octon^e, ellipsoidete, simplices, incolores, longit. 0,009-1 8™™-, cras- sit. 0,005-9""-, paraphysibus conglutinatis. Spermatia minuta, recta, in sterigmatibus simpliciusculis. — On lime rocks, Alabama, Judge Peters. Suggests L. mammlllaris (Gouan) Duf., of the soutli of Europe ; but the areoles, for the most part, are little more than a quarter of the size of those of the European lichen. Tiiey occur now in a reduced, glebous state, which is quite smooth, glaucescent, and finally crowded into a close crust ; but are more commonly discrete, when the effigurate margin is manifest, the color often darkens, and the surface is at length prettily marked with striae radiating from the apothecium, instead of becoming cancellated, as in the foreign plant. As seen in section, no important differences are observed in the internal structure of the apothecium of our lichen from that of X. mammilhiris, though the thinner hypothecium of ours is possibly also paler. I cannot recognize in either the distinctly twofold hypothecium sometimes at- tributed to this group of Lecidece.

OP ARTS AND SCIENCES. 181

Lectpea psephota, sp. nov. : thallo areolato albo, areolis mitiutis tumidiilis discretis, hypothallo nigro ; apotheciis perruiuutis (latit. 0,2-0,4 mm.) areolis plerumqne immixtis e concavo planis margine tenui incurvo persistente, saepe angulo.so-difformibus. Hypothecium nigrum. Sporje in tliecis ventricosis octonse, elli[)Soideas, simplices, incolores, longit. 0,012-20™'"-, crassit. 0,007-10"""-, paraphysibiis con- cretis. — On granite rocks, shores of Straits of Magellan, accompanying (in the specimen) BuelUa petrcea b. vulgaris and B. geographica, Rev. T. Hill (Hassler exp. 1872). The lichen itself not a little resembles B. stellulata (Tayl.).

Lecidea tessellina, sp. nov. : thallo rimoso-areolato glaucescente (cinerascente vel dein sublutescente) areolis planis Isevigatisque (rarius turgidis) hypothallo atro subinde marginatis ; apotheciis minutis (latit. 0,3-07 mm.) areolis immersis e concavo mox planis nudis, margine tenui acuto subpersistente, demum confluenti-difformibus. Hypothe- cium incolor. Sporse octonfe, ellipsoideae, simplices, incolores, longit. 0,009-14°""-, crassit. 0,005-7"""-, para|)hysibus coalitis. — Common on •various rocks throughout the Appalachian range, and observed also ■westward, in Kansas and Missouri, by E. Htdl. A well-marked lichen, which I long tried to consider a lecideoid Lecanora (§ Aspicilin), with which group it accords, moreover, in its spermogones and staff-shaped spermatia on subsim[)le sterigmas. The rtniction of tlie thallus with K. is yellow (becoming in time reddish), and that of the hymeneal gelatine with iodine, blue.

Lecidea cyrtidia, sp. nov. : thallo effuso tenuissimo leproso oli- vaceo-virente ; apotheciis perminutis (latit. 0,2-0,4 mm.) appressis mox conv^exis immarginatisque. Hypotliecinm nigrum. Sporie 6-8"® ovoideo-ellipsoideis, sim|)lices nebulosiE vel pseudo-biloculares, incolores, longit. 0,006-10""-, crassit. 0.0025-45""'-, paraphysibus coalilis. — On sandstone, IMissouri, B. Hall ; Pebbles, Quincy, Mass., H. Willey. A very humble, but yet marked, lichen.

APPEXDIX.

Kerguet.en Lichens. A brief notice of lichens collected in Ker- guelen's Land by Dr. Kidder, Naturalist of the United Statt-s Transit Expedition in 1874-75, as of a few others gathered previously in the same island by Dr. Hooker, and now preserved in the late Dr. Thomas Taylor's herbarium (Herb. Bost. Soc. Nat. Hist.), was prepared and published by the present writer in the Bulletin of the Toney Bot. Club, Vol. VI. No. 10 (Oct. 1875). In the November following, a note on " New Lichens from Kerguelea Land," joUected by the Rev.

182 PROCEEDINGS OF THE AMERICAN ACADEMY

A. E. Eaton, of the British Transit Expedition, and determined by Dr. Nylander, was publi.<hed by tlie Rev. J. M. Crombie in the "Jour- nal of Botany," and was followed by a full enumeration of Mr. Eaton's lichens by the same gentleman, with tlie same assistance, in the '• Jour- nal of the London Linnaean Society, Vol. XV. ; as now, at length, by a " Revision of the Kerguelen Lichens collected by Dr. Hooker," in the "Journal of Botany," for April, 1877. The naturalist of the Brit- ish expedition had much better luck m collecting, amid the countless discouragements of the " island of desolation," or was less embarrassed by other and higher branches of natural history, than ours ; and Messrs. Nylander and Ci-ombie have tiius been able to largely extend this cu- rious lichen-flora ; while a comparison with Dr. Hooker's specimens (very few, indeed, of which could be discovered in the herbarium of Dr. Taylor) has enabled them to determine some of the latter writer's new species, fbc the determination of which his own descriptions were entirely inadequate. There is also something over a page, in Mr. Crombie's last paper, of observations on the present writer's list of Kerguelen lichens above mentioned, upon which it will be proper to make some remarks.

And first as to what is called the unfortunate " neglect of the chemi- cal reactions," which, it is said, renders the " diagnosis incomplete, and so far uncertain." This is simply a matter of opinion. I studied the question of the use of certain chemicals in the systematic investigation of lichens, witli such care as I could give it, ten years ago, and have since seen no reason to change the view then expressed (Amer. Natu- ralist, April, 1868). The application to the lichen-tissues of the tests used is not without interest, and may give results of some utility, so far at least as they go ; but this quantum vidctar impedes every stage of the inquiry, and the unequivocal value assumed for the results has never been any thing but an assumption. And opinions may also differ as to the value of the chemical "species" which have resulted from the " reactions." Dr. Nylander has remarked of one of these species, his Parmelia cetrarioides, that it scarcely differs from another except chemi- cally, — " vix differt nisi reactione. . . . a P. oUvetorum : at distin- guenda est nomine propria, Jam earn ob causam" (Nyl. Obs. Lich. Pyr. Orient, p. i 6), and his remark is applicable to not a few others, whether or not now appearing to be supported by secondary lichen-characters. I decline, for my part, to receive such species. And there can be no doubt that the tendency of this scrutiny of " the reactions," as of another now far from unknown method <.f study, — the scrutiny, that is, of minute and not seldom unimportant differences of all sorts, to the ignoring, for

OP ARTS AND SCIENCES. 183

the time at least (whatever may be intended in tlie future), of the more difficult and important consideration in full of the points of agreement with known forms, — is simply to minimize the value of species; and can have but one I'esult, and that only a disastrous one, on the future of Licheiiology.

Usaea sulplmrea (Miill.), Th. Fr., is the same certainly as Neuro- pogon meluxanthiis (Ach.) Nyl. But it is not questioned that the lichen named is indigenous to both the Arctic and Antarctic zones, and was first published from the former under the name first cited above. The fact that the Arctic condition is less luxuriant than the other can make no difference in the application of the universally recognized rule of nomenclature, which overrides individual preferences, and is intended to. But my reviewer continues tliut '* Tuckerman also seems to imply that Neuropogon Taylori (Hook, fil.) cannot rightly be discriminated from the preceding." It was, perhaps, rather more than implied. Hav- ing, for many years, been in receipt of specimens of the yellow Usnea of the polar regions, especially of the antarctic forms, it became a matter of some interest to me to determine the U. 2\(yh>ri, considered (it should appear) by Dr. Taylor to take the [)lace, in Kerguelen's Land, of the older species ; but not likely to be restricted to the island. The endeavor was in vain, and even in Dr. Kidder's large Kei'guelen col- lection there was nothing that appeared separable from the [)l:int of the Falkland Islands, as there was nothing in either Taylor's or Nylauder's diagnosis of U. Taylori satisfactorily to distinguish it.

Pannaria Taylori, Tnckerm. ubi sup., Oct. 187.5, which was de- scribed from a specimen without name in the Taylor lierbarinm, is the same, it fully appears, as the P. placodiopsis, Nyl, of the ".Journal of Botany," of November of the same year. But Mr. Cronibie is now able t(» show, from Dr. Hooker's specimen, that the lichen is Lecanora dichroa, Tayl., which would hardly be guessed from the description. That certainly seems to indicate an areolate, oidy sub-effigiirate plant, of much the type of Lecanora gelida ; and by no means this marked Pannaria.

'^^ Pannaria glaucella, Tuck., sp. n. = Amphidium molyhdoplacum, Nyl." I cite this definite statement as it stands in Mr. Crombie's paper. It seems, however, from the evidence of the same gentleman, that there is no doubt at all that the plant is new ; or that it was published by one writer, under the specific name glaucella in October, and by another under that of molyhdoplaca, in tiie following November. This should appear to settle the name of the species ; but what of the g>'nus, and where is it defined ? The only reference to it that I can discover is in

184 PROCEEDINGS OF THE AMERICAN ACADEMY

Dr. Nylander's Obs. Lich. in Pijren. 1873, p. 48, where a " Leptogmm (Ampkidium) terrenum " is described, and the remark immediately follows, that this new Leptogimn of the new section AmphicUum is really to be taken for a new genus, — ^' genus novum quoad thalluin, quasi Pan- naria . . . sed sporce solitce Leptogii . . . Genus Amphidium nnndum satis cognitum." But the Amphidium of Kerguelen's Land differs con- siderably from the Pyrenean one, and the proposed genus seems as far from establishment as ever. In his full diagnosis of tlie species in Mr. Crombie's " Enumeration of Kerguelen Lichens," cited above. Dr. Ny- lander compares it with Pannaria elceina. I must still consider the affinity of the plant Pannariine and not CoUemeine, and continue to call it Pannaria glaucella.

Placodium hicolor, Tuckerm. uhi sup., is, without doubt, correctly referred by Messrs. Nylander and Crombie to Lecanora gelida, v. late- ritia, Nyl. I had myself remarked that my plant was the same with the red L. gelida of Taylor's herl)ariiim, upon which, doubtless, Nylan- der founded his Squamaria luteritia {Enum. Gen. Lich.), but the color suggested Placodium, and the spores seemed to look the same way. The polar-bilocular type (whicli is hardly well named '' placodiomor- phous ") is, indeed, a very distinct one ; but its exhibition in nature, if we limit groups rather by the sum of their characters than by any par- ticular character, is now far enouujh from distinct.

" Urceolina Kergueliensls *, Tuck., n. gen. S^ sp. = Lecanora Ker- guelensis (Tuck.)." I cite once more from Mr. Crombie's revision ; and can but repeat here, in reply to Dr. Nylander's criticism, what I said at first: " the lichen is not referable to Lecanora § Aspicilia, and is excluded by its exciple from § Sfpiamaria;" as, of course, from the section re|)resented by L. suhfusca. The apothecium certainly carries the plant into the Urceolariei, as these have been understood, and is irreconcilable with the Lecanorine type. It is true that Nylander has not recognized this sub-family, referring, from the first, Gyalecta to Le- cidea, Nyl., and proposing to unite even Urceolaria with Lecanora (in fact, U. scruposa really appears as Lecanora ( Urceolaria) scruposa, Ach., Nyl., in Norrlin Beratlelse in Not. Scilsk. p. F. ^ Fl. Fork., 13, 1873) ; but the latter of these emendations of the system is now given

* A better word, perhaps, than eitlier Kerguehnsis, which Messrs. Nylander and Crombie have taken leave to sub.stitute for it in the cited pajier, or Kergue- lena, which tliey elsewiiere employ. It is formed from Kerguelia, an attempt at a short latinization of the land or island of Kerguelen. Kergudenia may be more correct, and Kergueleniensis ; but hardly Kerguela.

OP ARTS AND SCIENCES. 185

up, and the former should appear to be also, as the learned author has of late described new S[)ecies of Gyalecta (Add. nov. in Flora Ratisb. 1875, 1876), though witliout any indication of his present opinion of the limits and place of tlie genus. Possibly, then, the new Urceolarii- form genus from Kerguelen's Land may hereafter come into favor.

To this it is only necessary to add that the fragment of rock upon which apothecia of BuelUa parnsema, as I certainly considered them, appeared, is no longer within reach. Dr. N} lander is of opinion that they are " probably to be referred to "the closely related B. wyriocarpa, which he has recognized on other fragments. But the former is a cosmopolitan lichen, and may well occur also.

186 PROCEEDINGS OP THE AMERICAN ACADEMY

XVI.

THEORY OF THE HORIZONTAL PHOTOHELIOGRAPH,

INCLUDING ITS APPLICATION TO THE DETERMINATION OF THE SOLAR PARALLAX BY MEANS OF TRANSITS OF VENUS.

Br Professor William Harkness, U. S. Navy.

Presented March 15th, 1877.

The terra "Horizontal Photolieliograph " is used to designate that form of Photolieliograph which, it is believed, was first employed by the late Professor Joseph Winlock; and which consists essentially of a fixed telescope whose optical axis is accurately horizontal and in the meridian, and whose objective is directed toward the same side of the zenith as the elevated pole ; the sun's rays being reflected into the telescope by a suitable heliostat. The sensitive plate for the reception of the photogra|)hic image, is, of course, situated at the chemical focus of the telescope ; the plane of the plate being perpendicular to, and its centre coinciding with, the optical axis of tho telescope.

S

D,

Fig. 1.

The details of the construction of the horizontal photoheliograph, in 60 far as they are necessary for a proper understanding of the theory of the instrument, are shown in Fig. 1.

A is the heliostat mirror, consisting of a piece of highly polished, but unsilvered glass, whose two surfaces make an angle of about sixty minutes with each other. The front surface is worked as truly plane as possible, and serves to reflect the solar rays through the objective, to the photographic plate. In working the back surface no particular pains are taken, and, on account of its inclination to the

OP ARTS AND SCIENCES.

187

front surface, any light reflected from it is thrown entirely away from the photographic plate. B is the objective, wliicl) is corrected for the chemical, and not for the visual rays. The distance between the objective and mirror is made as small as possible, consistently with keeping the latter clear of the shadow of the former. D is the reti- cule, the construction and use of which will be ex[)lained presently. C is the photograpliic plate, the sensitive surface of wliich faces the objective. Tlie rays from the sun S are reflected by tlie mirror A through the objective B, and after traversing the reticule D they form an image upon the photographic plate C.

The reticule consists of a system of squares, formed by the inter- section of two systems of very fine, straight lines, wbicli are drawn

upon one side of, and respectively paral- lel to the edges of, a thin, square plate of piano-parallel glass ; as shown in Fig. 2. In each of these linear sys- tems the number of lines is odd, and the middle line is drawn through the centre of the plate. This reticule is fixed at D, Fig. 1, with its rided sur- face toward, parallel to, and two or three millimeters distant from, the sensitive surface of the plate C. Moreover, one of the two systems of lines is set as nearly as possible vertical, and its inclination is accurately deter- mined ; and as an additional safeguard, a plumb line, consisting of a silver wire about 0.05 of a millimeter in diameter, is suspended between the reticule and the photographic plate, in suih a position that it may hang freely, and at the same time be very nearly in the vertical plane passing through the centres of the reticule and objective. As the light from the objective traverses the reticule bifore it reaches the photographic plate, the shadow, both of the reticule and of the plumb line, is impressed upon every picture taken with the apparatus ; and thus three different ends are gained : Firstly, by comparing the squares of the reticule witli the corresponding ones upon the picture, every thing relating to the shrinkage of the c'dlddion can be deter- mined ; secondly, the impression of the plumb-line, and also that of the vertical lines, furnishes upon each picture a fixed direction from which to measure angles of position ; and, thirdly, the intersection of the middle vertical with the middle horizontal line furnishes a fixed point, which will hereafter be designated as the centre of the

_.pi^.

Fig. 2.

188 PROCEEDINGS OP THE AMERICAN ACADEMY

plate. To determine the zenith distance and azimuth of this point it is necessary to measure the zenith distance and azimuth of the corresj^onding point of the reticule, as seen from tlie second principal point of the objective. P'or that purpose the mirror A, Fig. 1, is temporarily removed, and a transit instrument is set up in front of the objective B, and in tlie prolongation of its axis. The objective thus becomes a collimator to the transit instrument, through the eyepiece of which the lines of the reticule may be observed as if they were at an infinite distance. It should be remarked, however, that, as the reticule is slightly inside the visual focus of the objective, it is not generally possible to obtain perfectly distinct vision of its lines and of the wires of the transit at the same time. This difficulty is obviated by mai'king the intersection of the middle vertical and middle horizontal lines of the reticule in such a distinct manner that the slight mal-adjustment of focus does not prevent it from being seen. Then, by means of the transit, the reticule is adjusted so that the point in question is very approximately in the meridian, and at a zenith distance of ninety degrees. Finally, the exact azimuth and zenith distance of the point are measured.

If the photoheliograf)h is employed to depict any object whose linear magnitude is such that it subtends an angle a at the first principal point of the oljective, and if the centre of the image coincides with the centre of the plate upon wliich it is taken ; then, no matter what may be the solar focal distance of the objective, the magnitude of the iuiajje will be

2 tan la (Z> + E" — T) (1)

where D is the distance between the back surfice of the objective and the sensitive surface of the photograi>hic plates, E" the distance from the back surface of the objective to its second principal point ; and T A correction due to the thickness of the reticule plate. It is thus evident that, in all calculations involving measurements of pic- tures taken with this apparatus, the value to be employed as the focal distance of the objective is

D-\- E" — T (2)

D is obtained by direct measurement, the accuracy of which must be such that the uncertainty of the resulting value will not exceed one part in ten thousand, and it is desirable that it should not ex- ceed one part in forty thousand. To obtain E" we put

n = refractive index of crown -jjlass lens.

n' = refractive index of flint-glass lens.

OP ARTS AND SCIENCES.

189

ne = thickness of crown-glass lens.

n'e' = thickness of Hint-jilass lens.

s = space between the interior surfaces of the crown

and flint lenses, measured along the optical axis. ()i — 1)/' = radius of first surface of crown lens. N. B. — This

is the surface nearest the heliostat. ()i — 1)/" = radius of second surface of crown lens. (»i' — l)y" = radius of first surface of flint lens. (n' — l)y^ = raiiius of second surface of flint lens.

= focal distance of crown-gla>s lens. = focal distance of flint-glass lens.

Then, from the "Dioptrische Untersuchungen " given ia "Gauss* "Werke," Vol. 5, pp. 262-2G5, we derive the formulce

^'

/'/"

qp' =

yw fi

(3)

And if the objective is an ordinary double achromatic, corrected either for the visual or chemical rays,

t' = s + '^ +

(4)

But if it is a single lens, then

f

(5)

a

A'V

To find the value of the correction T, let abed, Fig. 3, be a section of the reticule plate, and let efhe a. ray of light incident upon it in

the plane of the paper. If this ray suffered no refraction, it would emerge from the plate at g ; but, owing to refraction, it actually does emerge at h, after which its path is parallel to ef produced. At k erect a perpen- dicular to be. It will be intersected at i by ef produced, and the distance hi will be the required value of T. Let t be the thickness of the glass composing the reticule plate ; n its index of refraction ; and i the angle of incidence of the ray ef. 'Then

190 PROCEEDINGS OP THE AMERICAN ACADEMY

n

and as i oannot exceed half a degree, its cosine will be very nearly unity, and it will be sufficiently accurate to write

T= '-i^i^ (7)

If we assume the reticule plate to be of crown glass, and its refractive index to be 1.53, then T =: 0.347 t; and it is evident that, in order to make 7" small, the reticule plate should be as thin as possible.

From the experience thus far had with the horizontal photohelio- graph, it appears that, if the focal distance of the objective is F, its clear aperture should be 0.0100 i^. The clear aperture of the helio- stat mirror, which is circular in form, should be 0.0142 i^. The plates upon which the pictures are taken should be square, and of such a size that their sides, as seen from the centre of the objective, may subtend an angle of about sixty minutes. This should also be the size of the reticule plate, and the distance between any two consecu- tive lines of the reticule should subtend an an^le of about four minutes. Throughout the remainder of this paper it will be assumed that these are the proportions of the apparatus. The actual focal distance of the objectives of the instruments heretofore constructed has generally been about twelve meters.

To avoid repetition, the notation which will be employed through- out the remainder of this paper is here given. Let PA, Fig. 4, be the meridian of the place of observation; P being the pole, and Z the zenith. Let S be the position of the sun as seen from the centre of the earth, and S^ its position as seen from the place of observation. Hereafter, to avoid circumlocution, S will be designated as the true, and S^ as the apparent, sun. Let v be the vertex of the apparent sun, and V the position of Venus as seen from the centre of the earth. Also, let M be the point where the normal to the heliostat mirror pierces the heavens, and V, S', S'^, and v', the positions of the re- flected images of Venus, the true sun, the apparent sun, and the vertex of the apparent sun, as seen from the second principal point of the photographic objective. Then the following notation will be adopted : —

(^ = latitude of the place of observation.

cp' = co-latitude of the place of observation = PZ = 90° — gj.

As =■ polar distance of true suu = PS.

OP ARTS AND SCIENCES.

191

Fig. 4.

192 PROCEEDINGS OP THE AMERICAN ACADEMY

A,. :^ polar distance of Venus = PV.

a's = polar distance of the reflected image of the true sun = PS'.

A'y = polar distance of the reflected image of Venus = PV.

tg = hour angle of true sun = APS.

ty = hour angle, of Venus = APV.

t's = hour angle of the reflected image of the true sun = APS'.

t'y = hour angle of the reflected image of Venus ^ APV.

^g = zenith distance of true sun = ZS.

^'s =: zenith distance of the reflected image of the true sun = ZS'.

^"s = zenith distance of the reflected image of the apparent

sun = ZS'^. t,'^, = zenith distance of the reflected image of Venus = ZV. As = azimuth of the true sun = AZS.

A's = azimuth of the reflected image of the true sun = AZS'. A"s = azimuth of the reflected image of the apparent sun = AZS'^. A'v = azimuth of the reflected image of Venus = AZV. d = the angle ZS'^S'. r =. the refraction.

7i' = the parallax in altitude. Hence r — tt' = SS^ = S'S'^. § = the angle ZS'V. 7 = the angle ZV'S'. X = the angle PS'V. Q =. the geocentric distance from centre of sun to centre of

Venus = S V = SV. CO = the geocentric position angle of Venus relatively to the sun's

centre = PSV. a z= the angle PVS. ^ =. the angle PSS'. yj = the angle PS'S.

We have next to show how pictures obtained vpith the horizontal photoheliograph may be measured, and the results expressed in terms of some one of the systems of spherical co-ordinates usually employed in astronomy.

Upon an engine arranged to give polar co-ordinates, the plate to be measured is carefully adjusted, so that the centre of the image of the sun coincides as accurately as possible with the origin of co-ordinates. The fixed line, from which the angles of the co-ordinates are to be measured, is taken perpendicular to the image of the plumb line ; the zero being toward that edge of the plate which was on the right hand, as viewed from the object glass, when the picture was taken, and (the

OF ARTS AND SCIENCES. 193

collodion side of the plate being nearest the observer) a motion of the radius vector iu the opposite direction to that of tiie hands of a watch corresponding to increasing angles. Then the distance from tlie origin of co-ordinates to the sun's limb is measured at every thirty degrees, throughout the whole circumference ; an<l the distances and angles to the centre of Venus, and to the centre of the plate, are also measured. Owing to the effect of refraction, the outline of the sun's image will not be circular, but may, with sufficient accuracy, be assumed to be an ellipse whose minor axis coincides with the vertical circle passing through the sun's centre. To find the position of the image of this vertical circle upon the photographic plate, we refer to Fig. 4 ; and remark that, owing to the equality of the angles of incidence and re- flection, S^M = S'^M, vM = v'M, and the angle S^My is equal to the angle S'^i^My'. Hence t^'S^S'ju = ^^S'^v', and ZS'^v' = ZS'^S^ -\- S^S'^r' = ZS'*S^ -|- ZS^S'^. But ZS'^ is the direction of the plumb line upon the plate, and S'^u' is the semi-minor axis of the elliptical image of the sun. To find the value of the angle ZS'j^w' we require the zenith distance and azimuth of the true sun, which are given by the formulae (8) ; the necessary data being, the exact instant at which the picture was taken, the right ascension and polar distance of the sun, and the latitude of the place of observation.

cot As tan JU = ■

cos tg

tan fg cos }f

tan As = ^ TTT

sin ((^ — Ji)

tan ^a

tan {(p — M) cos Ag

(8)

The zenith distance, ^"s, and azimiith A"g, of the reflected image of the apparent sun, are found by methods explained in a subsequent part of this paper. Then, in the spherical triangle ZS^S'^^, the angle S*ZS'« is equal to Ag ~ A"s, ZS'» = C"«, and ZS, = Lg — r -\- 7t', where r and n' are the refraction, and parallax in altitude. Whence, putting the angle ZS>' = 180° — 0,

Thus the anjrle upon the photographic plate, between the fixed line of reference and the major axis of the image of the apparent sun, will

VOL. XII. (n. S. IV.) 13

194

PROCEEDINGS OP THE AMERICAN ACADEMY

be d ; and if R and £ are the polar co-ordinates of any point of the limb of this ima^e, its rectanofiiUxr co-ordinates, referred to its axes and approximate centre will be

y' = R sin (e ^ Q) x' = R cos (e =F G)

(10)

in which the upper signs are to be taken when the sun is west, and the lower when it is east, of the meridian.

Owing to atmospheric disturbances, the image of the sun's limb will generally be more or less irregular, and no matter liow carefully it may be centred on the measuring engine, the point from'which the measures are made will seldom coincide quite accurately with the centre of the image. On this account, to obtain the co-ordinates of any point of the limb referred rigorously to the centre and axes, the equations (10) must be corrected by the small quantities 8y and dx, and thus we get

y = Rsm (£ T 6) + %' X = R cos (e =F ^) + ^^

(11)

The image of the sun's limb being taken as an ellipse, its equation will be

0 = — A'B'' + AY + ^x^ (12)

where A and B are respectively the horizontal and vertical semi- diameters of the sun, affected by refraction and parallax. Putting ^' = nJt^ substituting this value in equation (12), and dividing by

A% we get

0 = — nA'- -{- f -{- nx^ (13)

Finally, substituting the values of y and x from the equations (11), neglectmg the squares of dy and 8x, and reducing, we obtain

+ 1 [sin^ (e rp ^) + ^ cos'^ (e ^^ 6)]R'

0 = <! _ ^ ^2 + sin (fc- qp 0) 8y -\- n cos (s T 6) dx

(14)

Each measurement of the sun's limb, made upon the photograph, gives one equation of the form (14), and from all the equations thus

OF ARTS AND SCIENCES. 195

obtained the values of A, 81/, and dx are found by the method of least squares.

The contraction of the sun's vertical serai-diaraeter on account of refraction will be J (r' — r ') ; where r' and r" are respectively the refraction of the lower and upper limbs. The contraction of the horizontal semi-diameter on account of refraction, for all zenith dis- tances less than 85°, may be taken as constant and equal to 0".25. Hence, if s represents the sun's semi-diameter, we have

/s-iir'-r")y

which is the value to be employed in equation (14).

As changes of refraction are not strictly proportional to changes of zenith distance, the centre of the sun's image will not coincide rigor- ously with tlie image of the sun's centre. Let the distance between those two points be 8r, and let r'" be the refraction of the sun's centre, r" and r' being respectively the refraction of his upper and lower limbs, as before. Then

8r = I {r' -\- r") — r'" (16)

and the co-ordinates of the image of the sun's centre are 81/ -\- 8r, and 8x. These rectangular co-ordinates are transformed into polar co- ordinates of our original system by means of the formulae

li=[(8r/+8ry+{8xy]i] Sy + Sr

s>n V = ^

5.r COS J? = -

(17)

where the double sign is to be taken in the same way as in equa tious (10).

The polar co-ordinates of the image of the centre of the apparent sun have thus been found ; and our original measurements gave the polar co-ordinates of the centres of the image of the apparent Venus and of the photographic plate. Let i?, H', R" be, respectively, the radii vectores, and s, «', e" the angles of these co-ordinates. Passing now to a system of rectangular co-ordinates whose origin is at the centre of the plate, and whose axis of X is parallel to the fixed

196

PROCEEDINGS OF THE AMERICAN ACADEMY

line of the original system of polar co-ordiuates ; we get for the image of the centre of the apparent sun,

3in e — B" sin s" "i

JOS e — i?" cos s" )

2/ = i? sin e — X = R cos i

and for the image of the centre of the apparent Venus y = B' sin £' — B" sin s" x' = R' cos e' — R" cos e"

(18)

(19)

Let it be assumed that when the picture was taken ^^ and A^ were the zenith distance and azimuth of the centre of the plate, as seen from the second principal point of the ol)jective ; and that i^was the reduced distance between the latter point and the sensitive surface of the plate, or in other words,

F=D-\- E" — T (20)

as given by equation (2). Further, let the angles subtended at the second principal point of the objective by the co-ordinates, _v, x,y', a;', of the equations (18) and (li)) be, respectively, d'Qg-, 5A> 5^,-, 8Ay. Then, as the plate was perpendicular to, and its centre coincided with, the optical axis of the objective,

i? sin e — R" sin e"

tau ou =

tan bAo =

tan 8^v =

tan dAi, =

		F
R	cos e -	—	R" cos e'l
		F
R'	sin e'	—	R"	sin e"
		F
R'	cos f '	—	R"	cos e"

F

(21)

Denoting by C"s^ ^"s, C'V, A"y, the apparent zenith distances and azimuths of the reflected images of the sun and Venus, as seen from the second principal point of the objective, we now have

A", = A + ^^*

A"y = ^0 + ^^y J

(22)

OP ABTS AND SCIENCES.

197

Tlie next step will be to free these zenith distances and azimuths from the effects of refraction and parallax. For that pur[)ose, con- sider the spherical triangle ZS S'*, Fig. 4 ; but instead of limiting the points S, S,j, S', S'^, to the sun, let them represent any heavenly body whatever. Then, ZS' = l' ; ZS'^ = ^" ; S'S'^ = SS^j^ = r — n' ; S'ZS'^it = A" ~ A' ; and ZS^^S' = d, the value of which is given by equation (9). The relations subsisting among these parts are,

sin ^ cos (A" ~ A') =

tan m = tan (r — n') cos d

cos (;• — it') sin {C" — "0

cos III

sin ^' sin (A" ^ A') = sia (r — n') sin d

(23)

To simplify these equations we remark that (r — n') will rarely amount to 5', and as cos d must always be less than unity, we may write with all needful accuracy

m = (r — 7i') cos d

(24)

^ will never differ from 90° by so much as 30', and therefore its sine may be taken as unity ; while as {A" ~ A') can scarcely amount to 5', and will usually be far less, we may write unity for its cosine, and substitute the arc for its sine. We thus find

C' = C" — (r — 7t') cos d A' = A" q: (r — 7t') sin 6

(2o)

As these equations are perfectly general, we have only to substitute in them, for ^" and A", the apparent zenith distances and azimuths of the images of the sun and Veuus, given by the equations (22), and there results the true zenith distances and azimuths of the images of these bodies, which are

Ts = Co — 5C« — (^s Tt's) cos ds

A's = ^0 + ^^s =F (r-s — n's) sin ds

^^ = To — 8Xv — (?V — Tt'v) COS dy A'v = Jq -[- 8A„ =F (r^ — n'v) sin d^ _

(26)

in which the upper signs are to be taken when the body is west, and the lower when it is east, of the meridian. Strictly speaking, the value of d will not be the same for Venus as for the sun, but the

198

PROCEEDINGS OP THE AMERICAN ACADEMY

difference will generally be so slight that either value may be em- ployed for both bodies.

The effect of parallax in azimuth in displacing Venus relatively to the sun's centre can never exceed 0".08, and will usually be much less; but, if it is thought desirable to correct the equations (26) on that account, the mode of doing so will be obvious wiien it is remem- bered that it will be sufficiently accurate to consider the parallax in azimuth as acting perpendicularly to the parallax in altitude.

From the zenith distances and azimuths given by the equations (26), the corresponding; polar distances and hour angles must next be found. The rigorous fbrmuliB for this purpose are

tan m = tan ^ cos A'

tan A' sin m

tan t =.

cos \(f> — m)

cotan A = tan (g) — in) cos t .

(27)

but A' will generally be so small that its cosine may be taken as unity, and then we may write

' tan t =

tan A' sin ^'

cos (<p — C) cotan A = tan (g) — ^') cos t

(28)

In the spherical triangle PS'V, Fig. 4, we have the relations

tan m = tan A 'v cos (t's — f V)

cos aV . , , .

sm o cos /, = sm (As — m)

^ cos »« ^ * ^

sin (» sin A = sin A V sin {t's ~ t'y) .

Usually it will be sufficiently accurate to put cos {t's and then m = a'v, and these equations become

sin Q cos X = sin {a's — A V) sin p sin A = sin A 'v sin (t's ~ t'^)

(29)

t'.) = 1,

(30)

from which q and X are obtained. As a check, q may be computed directly from the zenith distances and azimuths furnished by the equations (26), the requisite formulae being

OF ARTS AND SCIENCES.

199

tan B ■

Q =

(.4^, ~ A'u) sin C's

i V f S

sin B cos B

From the spherical triangle PSS', Fig. 4, we get

cos i (A', — A,)

(31)

tan 1 (x + V) =

tan H;f — '^) = .7

cos i (A'^ + A,) A.)

sin i {A's + AJ

cot J (<'s cot L (f.

ts)

ts)

(32)

Referrino- ao^ain to Figf. 4, it is evident that SV is the distance, and PSV the position angle of Venus from the centre of the sun. To find the values of these quantities we have

SV=S'Y' = Q )

K33)

PSV = PSS'±S'SV = PSS'±SS'V = PSS'±PS'S=fPS'V')

But PSV = w, PSS' = X, PS'S = xp, PS'V = X, and thus we get

03 = (z ± V) T ^ (34)

in which the upper signs are to be taken when PS'S is greater than PS'V, and the lower when PS'S is less than PS'V. If it is assumed that the pole which forms part of the triangle PSV is always the elevated one ; and also that position angles are counted from the north around by the east ; then, in the northern hemisphere, when the sun is east of the meridian the position angle will be 360° — w, wliile west of the meridian it will be w ; and in the southern hemisphere, when the sun is east of the meridian the position angle will be 180° -|- w, while west of the meridian it will be 180° — m.

Finally, if the polar distance of Venus, and the difference between her right ascension and that of the sun are required, these quantities may be obtained from the spherical triangle PSV by means of the

formulae

tan n = tan q cos (o

tan A V cos («« ~ «^) = tan (As — n)

sin n tan a tan A ^ sin («« ~ «^) =

(35)

cos (A^ — ii)

in which a, and a^ are respectively the right ascensions of the sun and of Venus.

200 PROCEEDINGS OF THE AMERICAN ACADEMY

In the preceding development of the theory of the horizontal photoheliograph, continual reference has been made to the centres of the sun and Venus, but of course it will be understood that all the equations apply equally well to any other pair of celestial objects which may have been photographed with the same apjjaratus.

As the horizontal photoheliograph was much used in observing the last transit of Venus, it is perhaps desirable to give here a direct method of deducing the solar parallax from the photographs then obtained. For that purpose consider the quadrilateral PZS'8, which is composed of the triangles PZS' and PS'S. In the triangle PZS' we have the relation

sin A's cot B =z sin ^'g cot <f' -(- cos ^', cos A' 3 (36)

in "which qp' is the colatitude, ZP; and £ is the angle ZS'P. Con- sidering all the parts, except gj', as variable, and differentiating, we get

dB = — - cos C'i (cot flp' c?l's + sin A's dA's)

sill A'g

4- cos A's ( - — -- sin ^'s d^'s — 4^^ cos B dA's) \sm A'g sin A'g /

(37)

To obtain approximately the maximum value of this differential,

we remark that A's can never exceed ± 13' ; and as sin B must

, IT 1 • ^, sin S , , , . , sin'^ B

always be less than sin A's , must be less than unity ; and

sin A\ •' sin A'^

must be less than sin A's , that is, it must be less than 0.004. ^'s can

never differ from 90° by more than ± 13', and therefore its sine may

be taken as unity, and its cosine cannot exceed 0.004. If the latitude

of the place of observation is less than 50°, g;' will be greater than

40°, and its cotangent will be less than 1.20. Substituting these

values in the second member of equation (37), all the terms except

the last become evanescent, and we may write, without an error of

one part in ten thousand,

dB= — dA', (38)

But the only way in which A's can be made to vary is by varying the adopted value of the solar paralkax, tts. Hence, as ZS' is nearly 90°, dA's is the resolved value of drts, and as it can never exceed that quantity, it is safe to write

dB = — drts (39)

OP ARTS AND SCIENCES. 201

In the triangle PSS' we have the relations cos %-=■ — cos T/; cos (1^ ~ <'$) -\- sin i/; sin (<, ~ t' ^ cos A j cos T/^ = — cos '1^ cos (i's ~ t'^ -j- sin ;f sin (4 ~ i'^) cos A '«

(40)

Considering all the parts as variable, differentiating, and reducing, we get

di = sin A 's sin (ts ~ t\) dAs — cos A ', d(t^ ~ t'^) — cos S8'd\p)

dip = sin A s sin {t^ ~ t't) dA's — cos A ^ dQ^ ~ t'j) — cos SS' dx )

Adding, this becomes

^~^ ^— l + uos SS' ^ ^

To obtain approximately the maximum value of this differential, we remark tliat at the time of the transit the sun's north polar distance was 112° 49', and therefore sin As = 0.922, and cos As = 0.388. If the latitude of the place of observation is not greater than 50°, the value of A's will lie between 130° and 180°; and consequently its sine will not exceed 0.766, and its cosine cannot be gi'eater than unity. Sin (tg ~ i's) cannot exceed unity. Further, as the triangle PSS' can only be varied by varying the assumed value of the solar parallax,* of As and dA's are the resolved values, and d {tg ~ t'g) is the sum of two resolved values of dTts. It is therefore certain that «?As and </a's are not greater than dTts, and that d{ts^t's) is not greater than 2 drCs. Substituting these values in equation (42), and adding all the terms, without regard to sign, we get

dy^dip= ^^'^''' (43)

^ ~ ^ 1 + C08 SS' ^ ^

* Strictly speaking, although the point S' can only be varied by varying the assumed value of the solar parallax, the point S can be varied, not only in that way, but also by varying the tabular place of the sun. In practice it will probably be best to neglect at first the errors of the solar tables, and after- wards, when tiiey become known from the solution of the final equations, to compute rigorously the value of dx + d\l/ for each photograph, by means of (42), and in all cases where it exceeds two or three seconds, which will rarely 'happen, the corresponding conditional equations of tlie form of (55) and (56) may be corrected so as to accord with the new values of the solar elements, and a second solution will give very accurate results.

202 PROCEEDINGS OF THE AMERICAN ACADEMY

Hence if SS' does not exceed 120° the value of c?/ -f" ^^ cannot be so great as 9 ditg. Adding to this the value of dB, fiona equation (39), we find th;it, under the circumstances specified above, the total variation of the sum of the angles ZS'S and PSS' cannot be so great as 10 djts. But it is not possible tliat the value of the solar parallax now generally adopted can be in error by so much as ()".2, and there- fore the value of 10 d;ts cannot be so great as 2" and will probably be less than 1".

Referrino^ to the fijjure, it is evident that

ZS'V + PSV = ZS'S + PSS' or

|3 4- w = ZS'S + PSS' (44)

As the angle ^ must be obtained from measurements made upon a photograph, it is not probable that it can be depended upon to within 5". It has just been shown that the right-hand member of (44) will not be vitiated so much as 2" by any possible error in the adopted value of the solar parallax. It therefore follows that the left-hand member of (44) may be regarded as constant, within the limits of eri'or of observation, and thus it appears that

— d^ = dco (45)

In the triangle ZS'V we have

o

tan 1 (^ -f ;/) = cot ^{A's^ A',)

(46)

from which ^ and y are derived. In the same triangle we also have the relations

cos Q = cos ^'i, cos (^'s -\- sin ^'y sin ^, cos (A's ~ A' J) )

[ (47) sin (A's ~ A'y) cot ^ = sin i^'j cot ^y — cos (A's ^ A'y) cos ^'s )

Considering all the parts as variable, differentiating and reducing, we find

dQ =z sin ^y sin yd(A's ~ A'y) -4- cos yd^'y -\- cos ^d^g

— smQd^=sin^'y cos y d(A's r^ A'y) — sin y c? ^^ -)- cos p sin ^ djs

OF ARTS AND SCIENCES.

203

Reverting to the equations (2G), putting n' i = Mrts, 7r'„ = iV;T„, Ks = /«;?,., where tt, and ;r^ are respectively the equatorial horizontal parallaxes of the sun and Venus ; regarding jtv as the variable, and difFerentiatiug, we get

dA's = ± »jjj/sin ds drty d^y = -j- -^ cos dv djtv dA'y = ± iV" sin dy ditv

(49)

Substituting these values in (48), writing unity for sin ^^, ds for ^„, and d(a for — dp, we obtain

dg = cos ds{_±. {mM±_ N) sin y tan ds -j- -A^cos y -\- mil/cos ^] (Ztt^ )

cos e . r (5<^)

dco=z— — :'[ ± (mJ/±i\r)cosj' tan (9^ — iV^sinj'-|-?Mil!/'sin^cos(>](^!7r„ }

From an epheraeris the polar distances of the sun and Venus, and the difference of their right ascensions are taken; and thus two sides and tiie iucluded angle are known in the triangle PSV. The remain- ing parts are given by the formulae

tan IX = tan A v cos («j — «,,) cos A.,

sin P(, cos cOf, = sin ( A « — u)

cos fi

sin Pq sin 0)^ = sin A v sin («s — «,,) sin pg sin a = sin A « sin (a, — «^)

(51)

in which we write p^ and co^^ to distinguish the quantities deduced from the ephemeris from the similar quantities q and w obtained from the photographs by means of the equations (30), (32), and (34). Still considering the triangle PSV, we have the relations

cos Qq = cos A V cos A J -|- sin Ay sin A $ cos («, — a^) sin («, — ciy) cot cOq = sin A s cot Av — cos A j cos (a, — Uv)

(52)

Regarding all the parts as variable, differentiating and reducing, we get

dn^ = sin A„ sin ad(^as -^ «^) -{- cos adAv -j- cos a)„<?As — sinp(,<?(Wo = sin A vCOsad^Uj ^ «^) — sincrc? A v -j- cos^q sin w^c? A $

(53)

204 PROCEEDINGS OF THE AMERICAN ACADEMY

If now «., «^, As, Avi'^si and Tt^ are the tabular values of the right ascensions, polar distance-*, and parallaxes of the sun and Venus ; and if as-\-d<is, «r -|- rf«;,, As -\- dAs, Av -\- dAv, rts-^drts, nv -f- drtv, are the true values of the same quantities; then we must have

Q -\- di) = Q^ -\- dn^ )

[ (54)

(o -\- d(o =^ cOq -\- c?a)„ )

Substituting the values of dQ, dQ^, doo, and dco^ from (50) and (53), we obtain finally

( Po — P ~f~ ^'" ^i> sin ""^(tti ~' Km) -1- cos (rdAy -\- cos w.dA. )

0 = ] [ (55)

( — cos e^ [J; {mM -i- iV) sin y tan ©^ + iV cos 7 + ^^^ cos fijdir^, )

(<l)^) — w : — - [sin A^ cos irdla,'^ay) — sin <rc?A„-j-cos p^ sin uodA^] )

^= cose ''"''' (56)

V ; — -^ [-l-(/ftJ/-J-.iV)cos 7 tan tf^. — iVsin7-|-'«-3i'siny3cosp]c?iry )

siu p

Each photograph furnishes one conditional equation of the form (55), and another of the form (56), and from all the equations thus obtained the values of 6?((iCj ~. «^), dAs, dAv-> and rf;Tr^are found by the method of least squares, the resulting value of the solar parallax being

ns -\- m drty (57)

At the time of the last transit the value of m was 0.2684. Tho term ± {mM ± N) of equations (55) and (56) is to be interpreted thus : When the sun and Venus are on opposite sides of the meridian, it will be -\- {mM-\- N) ; when the sun and Venus are on the same side of the meridian, if the sun is most distant from the meridian, it will be -|~ (juM — N) ; but if Venus is most distant from the me- ridian, then it will be — {mM — N).

It will not escape notice that those parts of equations (55) and (56) which correspond to q^ -\- do^, and w^ -\- doj^, of the equations (54), are general for the whole earth, and can therefore be tabulated at suitable intt-rvals for the period of the transit ; while the terms which correspond to p -f" ^Qj and w -|- da, must be computed specially for each photograph.

Washington, Nov. 15, 1876

OP ARTS AND SCIENCES. 205

XVIL

ON DIAMIDO-SULPIIOBENZIDE-DICARBONIC ACID. By Arthur Michael axd T. H. Norton.

Presented by E. N. Horsford, May 9th, 1877.

Of the large number of amido-sulpho-benznic acids which are possi- ble according to our present theories, but three have been obtained thus far. Two of tiiese were prepared by Griess,* from the action of sulphuric acid on meta-araido-benzoic acid. Limpricht and Uslarf obtained the third by reduction of the mono-iiitro derivative of meta-sulpho-beuzoic acid. It seemed therefore of interest to us to study the action of sulphuric acid on ortlio-amido-benzoic acid and para-amido-benzoic acids, not merely in oider to increase the list of isomeric amido-sulpho-benzoic acids, but because of the possibility that, by removal of the amido group, the as yet uuliuowu ortho-sulpho- benzoic acid could be obtained.

Our experiments were first directed to para-amido-benzoic acid ; and here an unexpected character was assumed by the reaction, the re- sults of which we briefly communicate.

We prepared the para-amido-benzoic acid for our purpose from the solid para-nitro-toluol, by oxidation and subsequent reduction of the nitro group. lu the former operation it was observed that much better results were obtained from treatment with potassium per- manganate, than from the methods hitherto used for this body, viz., with nitric acid or potassium bichromate and sulphuric acid. The best proportions were found to be 2.V mol. KMuO^ to 1 mol. C6H^(NO^)(CIl3) in a solution of 40 parts water to I part KMnO^. The reduction was effected by means of tin and hydrochloric acid, in proportions 1 part CaH^(NO^)(COOH) to 2.15 parts Su. In order

* Jour. f. prakt. Cliemie [21, 5, 214. t Ann. Chem. Pharm., 106, 29.

206 PROCEEDINGS OF THE AMERICAN ACADEMY

to remove the excess of hydrochloric acid previous to the precipitation of the tin, tlie sohition is evaporated on the water-bath to dryness. The temperature should not, however, go beyond this point, as we had opportunity to observe that even at lOC^ small quantities of aniline were formed, while at 12t>'' the para-amido-benzoic acid was decom- posed completely iuto carbonic acid and aniline. It would be of interest to examine the action of SnClg on other aromatic acids under the conditions mentioned. The solution of para-amido-benzoic acid was treated with sodium carbonate, and the acid precipitated out by means of acetic acid. After a single crystallization in water, it showed the melting point 18G°.

The para-amido-benzoic acid obtained in this way was placed in a flask, and a sufficient quantity of slightly fuming sulphuric acid (s. g. 1.850) added to dissolve the mass. Tiie flask was then exposed to a temperature of 170* — 190", for from three to four hours, in a paraffine bath. After cooling, the contents of the flask were removed by means of water, and barium-carbonate was added to the solution until it was neutralized. The liquid was boiled for several hours, and then filtered. It was necessary to heat the residue repeatedly with hot water before a slight pinkish Ime could be removed. Exactly enough sulphuric acid was added to the filtrate to precipitate the baruun, and it was separated from the barium sulphate formed. By the evaporation of this solution, groups of crystals separated out, showing various shades of yellow, orange, and red. Several crystallizations from water freed tliem from small quantities of a by-product consisting of minute red crystals, and after boiling with animal charcoal they retained a faint pink color. The substance was dried at 110°, and submitted to a series of analyses. The sulphonic acid which was expected as the natural result of the reaction, would have yielded the following percentages: —

\

COOH

J

C — 38.7 11= 3.3 S = 14.5

LN= 6.4

The analyses showed, however, that we had obtained a body of an entirely diiferent nature, and led to the following formula : —

OP ARTS AND SCIENCES. 207

Calculated. Found (mean).

C = 50.00 50.18

H = 3.57 4.20

N == 8.26 8.06

S = 9.60 10.10 O = 28.57 100.00 This formula would naturally be resolved into the structural for-

^^\ /COOII

mula,

'' "XNH,

■2

or diamido-sulphobenzide-dicai-bonic acid, the reaction being as fol- lows : —

an.

/NH,

/NIL / ' '\COOH

2 an/ ' + H,so, = 2 H,o 4- SO2 ^^^„

' '\COOH ^ ' * \ /COOH

' '\NH2

The melting point of the acid is above 350°. It is easily soluble in hot water, and on cooling separates out in groups of fern-shaped crystals. It is much less soluble in alcohol and ether, their addition to the aqueous solution causing the precipitation of the acid in a white, flocculent mass; chloroform dissolves it with difficulty; while it is almost entirely insolulde in carbon bisulphide and benzine. Sul- phuric acid dissolves it easily, forming a compound which is pre- cipitated on the addition of alcohol, and is extremely soluble in water. This compound awaits farther investigation. In concentrated hydro- chloric acid it is completely insoluble. It dissolves easily in warm nitric acid, but cannot be precipitated by the addition of alcohol.

The new compound exhibits strongly marked acid properties, and dissolves easily in alkalies. The neutral solution in ammonia yields on evaporation the ammonium salt, in handsome laminated crystals, which are easily soluble.

The potassium salt obtained in the same way consists of small, fine, colorless needles.

The lead salt is white, and nearly insoluble in water.

208 PROCEEDINGS OP THE AMERICAN ACADEMY

The silver salt precipitated from the solution of the ammonium salt by the addition of nitrate of silver, is obtained in the form of small, white laminae, which are tolerably insoluble in water, and gradually assume a brown color on exposure to the sunlight. The analysis of this salt coincided closely with the formula

/ ' '\COOAff SO.,

Xntr/

an

COOAff

o

6'-^3

xnh^

Calculated. Found.

Ag= 37.45 37.62

The barium salt is extremely soluble, and not adapted for analysis.

The reaction of para-amido-benzoic acid, just described, recalls the analogous reaction of phenol with sulphuric acid. Glutzt* and Annaheim t have shown that, if an excess of sulphuric acid I )e avoided, oxysulpho-benzide is obtained with great ease. As in the case of oxysulpho-betizide and all members of the snlphine group, our com- pound should also pass over into the corresponding sulphonic acid, by increasing the amount of sulphuric acid used.

Unfortunately we are compelled temporarily to interrupt the in- vestigation, but hope at an early date to be able to communicate farther experiments in the direction mentioned.

Merz and Weith J obtained several years since a dicarboxyl-sulph-

carbauilid,

/NHQirCOOH

XNnCgii^cooii

a well-defined crystalline compound, by the action of carbon disul- phide on metamido-benzoic acid. We have sought to prepare the corresponding derivative of para-amido-benzoic acid, but so far without success. The alcoholic solution of carbon disulphide and para-amido- benzoic acid was heated in an open flask and in sealed tubes at various temperatures. In all cases we obtained a yellow, resinous mass, from which no well-characterized compound could be separated.

Berlin, Univeksitats-Laboratorium, April, 1877.

* Ann. Chem. Pharm., 147, 52. t Ann. Chera. Pharm., 172, 28.

t Ber. Deutsch. Chem. Gesell., 3, 812.

OF ARTS AND SCIENCES. 209

XVIII.

CONTllIBUTIONS FROM THE CHEAOCAL LABORATORY OF HARVARD COLLEGE.

RESEARCHES ON THE SUBSTITUTED BENZYL COM- POUNDS.

By C. Lorixg Jacksox.

Presented, June 14th, 1S76. INTRODUCTION.

The existence of the benzyl compounds was first established by Cannizaro,* in 1853 ; for, although Liebig and Wohler.t in their clas- sical research on the benzoyl compounds, obtained benzylalcohol as a secondary product from the action of ^lotassic hydrate on benzaldehyd, they merely spoke of it as an oily liquid, and did not determine its composition or properties. It was also Cannizaro t who, in 1855, showed that toluol, when treated with chlorine, yielded a substance identical with the benzylchloride prepared fi-om benzylalcohol by means of hydrochloric acid. The nature of the action of chlorine on toluol was not, however, thoroughly understood until Beilsteia and Geituer,§ in 1866, found that chlorine converted cold toluol into chlor- toluol, while, with boiling toluol, it yielded benzylchloride. In the same paper, they predicted that pure chlorbenzylchloride could be pre- pared by the action of chlorine, either on hot chlortoluol or on cold ben- zylchloride. Both these methods were tried successfully by Neuhof || in the same year, but the chlorbenzylchloride thus obtained was not the first substituted benzyl compound known, as Beilstein ^ had already obtained the chlorbenzylmercaptan, and Naquet** the chlorbenzyle- thylether, from the mixture of dichlortoluols, made by acting upon toluol

* Ann. Chem. Pharni., 88, p. 129. t lb., 3, p. 249. t lb., 96, p. 246.

§ Beilstein and Geitner, Ann. Chem. Pharm., 139, p. 331. 11 Neuhof, Zeitschr. der Chem., '66, p. 653. T Beilstein, Ann. Chem. Pharm., 116, p. 346. ** Naquet, ib., Sup. 2, p. 250. Comptes Rend., 56, p, 129.

VOL. XII. (n. S. IV.) 14

210 PROCEEDINGS OF THE AMERICAN ACADEMY

with chlorine. Immediately after the preparation of the pure chlor- benzylchloride by Neuhof, many of its derivatives were studied by Beilstein and Kuhlberg and Neuhof;* and the two former extended their investigations to the chlorbenzyl compounds containing more than one atom of chlorine attached to the benzole ring. Since that time, but little attention has been given to this class of compounds ; the only researches being those of Bohler,t and later, Vogt and Henninger,| on the sulphoacids, of Berlin,§ who obtained some curious results from the amines, and of Sintenis,|| who investigated the ethers.

Beside these chlorbenzyl compounds, only two other classes of sub- stances lying within the range of this paper have been studied, the nitrobenzyl compounds, — the first of which, nitrobenzylchloride, was described by Beilstein and Geitner in 1866, in the paper already referred to ; IT its derivatives were further studied by Grimaux,** Beilstein, and Kuhlberg.ff Bohler,t$ Strakosch,§§ Czumpelik.|||| Radziszewski,1[ir Henry,*** and Jackson ; fff and a few amidobenzyl compounds, the cyanide prepared by Czumpelik,||| and the amines by Strakosch.§§§

All these substances belonged to the para series, and no isomeric chlor- or nitrobenzyl compounds were known with the exception, perhaps, of the monochlorbenzylsulphosalts described by Vogt and Henninger, {|||{| and the isomeric nitrobenzylalcohol obtained by Gri-

* Beilstein, KuhlLerg, Neuhof, Ann. Chera. Pliarm., 147, p. 339; ib., 150. p. 280 ; ib., 146, p. 3iy.

t Biihler, Zeitschr. Chem., 1868, p. 440.

t Vogt, Henninger, Ann. Chim. Pliys. [4], 27, p. 130; Ann. Chem. Piiarm., 165, p. 362.

§ Berlin, Ann. Chem. Pharm., 151, p. 137.

II Sintenis, ib., 161, p. 329.

TF Beilstein and Geitner, Ann. Chem. Pharm., 139, p. 331.

** Grimaux, Comptes Rend., LXV., p. 211 ; Ann. Chem. Pharm., 145, p. 46.

tt Beilstein, Kuhlberg, Neuhof, Ann. Chem. Pharm., 147, p. 339; ib., 150, p. 286 ; ib., 146, p. 319.

U Bohler, Zeitschr. Chem., 1868, p. 440.

§§ Strakosch, Ber. D. Ch. G., 1872, p. 692. nil Czumpelik, ib., 1870, p. 473.

ITF Radziszewski, ib., 1870, p. 198.

*** Henry, ib., 1869, p. 637.

ttt Jackson, ib., 1875, p. 321.

Jtt Ozumpelik, ib., 1870, p. 473.

§§§ Strakosch, ib., 1872, p. 692.

lijlll Vogt, Henninger, Ann. Chim. Phys. f4J,27, p. 130; Ann. Chem. Pharm., 165, p. 362.

OF ARTS AND SCIENCES. 211

maux* from uitrobenzaldehyd, until Wachendorff,t in 1875, described the orthonitrobenzylbromide aud chloride. Soon after, iu a preliminary notice! of a portion of the work contained in these papers, the para- mela- and orthobrombenzylbromides were described ; finallj^, in 1877,Wachen- dorff published a very interesting paper § upon the nitrobenzylchlorides aud bromides, in which he described the metanitrobenzylbromide, and called attention to the striking foct that metanitrobenzylchloride could not be obtained under conditions which gave without difficulty the paranitrobenzylchloride, while he had not as yet succeeded in obtain- ing the orthonitrobenzylbromide under the conditions which furnished both of its isomeres ; he said, however, that he did not despair of ob- taining it by new'experiments under different conditions ; from this it would seem probable that the statements made in his preliminary notice in regard to orthonitrobenzylchloride and bromide, have been proved incorrect by his later exi^eriments.

The object of these papers is to add to our knowledge of this little studied class of compounds, and, also, to make some comparisons be- tween the replaceability of the haloid atoms in the side-chain, which it is hoped may in the future throw some light upon the nature of chemi- cal attraction. The substituted benzylbromides have been used as the starting-point for each class of compounds, because these substances can be easily obtained by the action of weighed amounts of bromine upou the corresponding substituted toluols in the state of vapor. This action of bromine on boiling toluol was first studied by Lautli and Gri- mauxjll Cannizaro,ir and Beilstein,** who proved that the substance thus formed was identical with the benzj^lbromide previously obtained by Kekule ft from benzylalcohol by means of hj^drobromic acid.

FIRST PAPER. OX CERTAIN SUBSTITUTED BENZYLBROMIDES.

C. LoKiNG Jackson. p Parabromhenzylbromide {C^H^Br.CH.^Br.). — Preparation. First

Method. Ten grammes of pure parabromtoluol, melting-point 28.5°,

* Grimaux, Comptes Rend., LXV., p. 211 ; Ann. Chem. Pharm., 145, p. 46. t Wachendorff, Ber. D. Ch. G., 1875, p. 1101.

I Jackson, ib., 1876, p. 931.

§ Wachendorff, Ann. Chem. Pharm., 185, p. 259.

II Lauth and Grimaux, Bull. Soc. Chim. [2], VII., p. 108. II Cannizaro, Ann. Chem. Pharm., 141, p. 198.

** Beilstein, ib., 143, p. 369. tt Kekule, Ann. Chem. Pharm., 137, p. 188.

212 PROCEEDINGS OF THE AMERICAN ACADEMY

either from the factory of Kahlbaum, in Berlin, or of Schuchardt, in Gor- litz, were heated to boiling in a small flask, through whose cork passed a return-cooler and the delivery-tube from a flask containing 10 gr. of bromine, the end of which within the flask was less than a centimeter above the sui'face of the bromtoluol ; the bromine was driven over in the form of vapor by heating the flask containing it with a small flame placed some distance below at such a rate that it was completely de- colorized at a few centimeters from the end of the exit-tube : to pre- vent condensation of the bromine, the delivery-tube was made as short as possible ; the heat was carefully regulated so that the bromtoluol boiled gently, the explosive boiling with evolution of white fumes, which was apt to occur toward the end of the process, being especially avoided. If these precautions were observed, the liquid solidified almost completely on cooling, and the substance was easily purified by j)ressing the crystals thus obtained between filter-paper and recrystal- lizing once or twice from hot alcohol. The average yield from ten grammes of parabromtoluol was ten grammes of parabrombenzylbro- mide, that is about sixty-eight per cent of the theoretical amount; but, if more than ten grammes of parabromtoluol were used in one opera- tion, the yield was not so large.

The substance was also obtained from the mixture of para- and ortho- bromtoluol,* prepared by treating cold toluol with bromine. On cooling the product of the action of bromine on the hot mixture with ice and salt, some parabrombenzylbromide separated out, and more was ob- tained by distilling off a part of the oil with steam, as the orthobrom- benzylbromide distils more easily with steam than the paracompound. This distillation is not to be recommended, however, as under these con. ditions a portion of the bromide is converted into the corresponding alcohol ; but without doubt this difficulty could be I'emoved by using hydrobromic acid in jilace of water. Compare p. 214.

Second Method. Benzylbromide was treated in the cold with an equal weight of bromine, to which a little iodine had been added ; on freezing the product of the reaction, a quantity of parabrombenzylbro- mide separated out. This method is decidedly inferior to that with pure parabromtoluol, as it not only gives a smaller yield, but also there is a i^ossibility that orthobrombenzylbromide may be formed. The composition of the parabrombenzylbromide was established by the fol- lowing analyses : —

0.5934 gr. of substance gave 0.7377 gr. CO2 and 0.1378 gr. H^O.

* Ann. Chem. Pliarm., 147, p. 39.

OF ARTS AND SCIENCES. 213

0.5679 <rr. of substance gave, after ignition, with CaO 0.8579 gr.

AgBr.

Required for C-HgBr^. Found.

Carbon 33.6 33.90

Hydrogen 2.4 2.57

Bi'omine 64.0 64.28

100.0 100.75

Properties. — Crystallized from alcohol, it forms thick, colorless nee- dles, with a brilliant lustre ; from the oily mother-liquor formed in its preparation or from benzole, it sejiarates on slow evaporation in well- formed prisms, apparently of the orthorhombic system, often a centime- ter or more long and two to four millimeters thick, which have the consistency of sublimed sal-ammoniac. Its odor is agreeable and aromatic, but its vapor attacks the mucous membrane with very great violence, causing tears and running at the nose ; it was observed, how- ever, by all who were exposed continually to its action that they became much less sensitive to it after a few days. "When brought upon the more delicate parts of the skin, it causes a sharp, stinging pain, but produces no such effect on the hands ; the taste is extremely biting, causing great pain to the tongue for several minutes ; it melts at 61-^°, can be distilled with steam, sublimes in laeedles, and burns with a lumi- nous green-bordered flame. It is almost insoluble in water, although it imparts its odor to it; (the flat needles, mentioned in a preliminary paper* as separating from water by spontaneous evaporation, were undoubtedly the more soluble parabrombenzylalcohol) ; it is but slightly soluble in cold, freely in hot alcohol, very readily in ether, benzole, carbonic disulphide, and glacial acetic acid. On one occasion, it was oxidized very rapidly by a mixture of potassic dichromate and dilute sulphuric acid, the action being attended by flashes of light visible even in diffused daylight, the product was an acid melting in the crude state at 239" to 240^*, which must therefore be parabrombenzoic acid.

It seems highly probable that this parabrombenzylbromide is the substance obtained, but not purified or studied by Lauth and Grimaux,t in 1866, in the residue from the distillation of bromtoluol ; since they described it as crystallizing in needles, and in the highest degree irritat- ing to the eyes.

* Ber. D. Ch. G., 1876, p. 931.

t Lauth and Grimaux, Bull. Soc. Chim. [2], V. p. 347.

214 PROCEEDINGS OF THE AMERICAN ACADEMY

m

Metahromhe7izylbromide (CfR^Br.CH.Br.) was made from meta- bromtoluol, prepared by Wroblevsky's * method (compare also Grete t)j as follows : 30 gr. of the mixture of para- and orthoacettoluid, obtained as a secondary product in Wroblevsky's process for purifying orthotoluidin, previously reduced to a granular condition by crystalli- zation from boiling-water, were suspended in cold water, and 45 gr. of bromine dissolved in water added in small portions at a time^ shak- ing until the yellow color disappeared after each addition ; the acetyl group was removed from the metabromacettoluid thus obtained by boiling with fuming hydrochloric acid in a flask with a return-cooler ; the base, set free by an alkali, was dissolved in portions of 10 gr. at a time in absolute alcohol, and the amido group replaced by hydro- gen by Griess's reaction ; the alcohol was then partly distilled off on the water-bath ; the residue distilled with steam, dried, and rectified, the portion passing over from 179° to 185°, being collected. To convert this into metabrombenzylbromide, 10 gr. of it were heated to boiling, and treated with 12 gr. of bromine in the way described under para- brombenzylbromide (see page 212) ; the slight excess of bromine over the molecular proportion was taken to allow for the loss in the pro- cess ; the metabromtoluol took up the bromine somewhat more slowly than the parabromtoluol. The liquid left after the brorairing was fin- ished, was distilled in a current of the vapor from hydrobromic acid (boiling-point 125°), prepared according to Naumann,]: until a con- siderable portion had passed over : the flask containing the substance was not heated for fear of decomposition. The hydrobromic acid vapor cannot be replaced by steam ; as under these conditions some of the brombenzylalcohol might be foi-med, although I am inclined to think that this reaction woul 1 take place much less readily here than it does in the case of the parabrombenzylbromide (compare page 212). The residue left in the flask was transferred to a funnel-tube, closed with a rubber stopper on a glass rod, and surrounded with ice. If the distillation had been carried on long enough, nearly the whole of the oil solidified to a dark, j^asty mass. The stopper was then removed, and the bi'own oil sucked out as completely as possible by means of the Bunsen pump. The white scales left on the funnel were boiled with a small quantity of alcohol ; the clear solution poured off from the undissolved oil and cooled in a corked flask. As soon as no more oil was

* Wroblevsky, Ann. Chem. Pharm., 168, p. 153.

t Grete, ib., 177, p. 231.

I Naumann, Ber. D. Ch. G., 1876, p. 1574.

OF ARTS AND SCIENCES. 215

■deposited, the clear liquid was decanted into another flask, and cooled with ice, when crystals were formed. The same process was repeated "with the mother-liquor and the residue until the whole was converted into crystals ; while another crop of less pure metabrombenzylbromide was obtained by adding snow to the mother-liquor from the final opera- tion. The crystals were purified by similar crystallizations from hot alcohol. It was necessary that all these operations should be carried on in corked flasks, as the metabrombenzylbromide, when moistened wnth alcohol, evaporated when exposed to the air so rapidly that there was a very considerable loss from working with open vessels.

The composition of the metabrombenzylbromide was established by the following analyses : —

0.4333 gr. substance gave after ignition with CaO 0.6609 gr. AgBr.

Required for C-HgBro. Found.

Carbon 33.6 " 34.63

Hydrogen 2.4 2.G6

Bromine 64.0 63.96

100.0 101.25

Properties. — Crystallized from alcohol by cooling, it forms white bladed needles or plates arranged in radiated groups ; by slow evaporation of its alcoholic solution, it can be obtained in flat prisms with square ends sometimes reaching a length of 3 cm., and a breadth of 2 mm. It has an agreeable odor, aromatic, but different fi-om that of the parabrom- beuzylbromide, while its action on the mucous membrane is even more violent, perhaps because it is more volatile ; its taste and action on the more delicate parts of the skin is similar to that of the para compound; it melts at 41°, can be distilled with steam only very slowly, sublimes in oily drops, and burns with a luminous flame having a green border. One of its most striking properties is that, when moistened with alcohol or ether, it evaporates very rapidl}'- ; whereas when dry it is comparatively fixed. It is almost insoluble in water, but imparts its odor to it, is freely soluble in cold, still more so in hot alcohol, and very readily soluble in ether, benzole, carbonic disulphide, and glacial acetic acid. An oxidizing mixture of potassic dichromate and dilute sulphuric acid seems to be without action on it ; but the same mixture converts the alcohol derived from it into an acid, which, in a not perfectly pure state, melts at 151° , and must therefore be metabrombenzoic acid.

o

Ortholromhenzylhromide {C^^H^Br.CH.Br.). — After several unsuc- cessful attempts to obtain an orthobromtoluol free from the para com-

216 PROCEEDINGS OP THE AMERICAN ACADEMY

pound from the mixture prepared by adding bromine to cooled toluol, I decided to insure a perfectly pure substance as my starting-point, by making the orthobi'omtoluol from orthotoluidin. The first method employed for purifying the orthotoluidin was that of Wroblevsky,* by boiling crude toluidin sixteen hours with glacial acetic acid ; but all the samples obtained by this process contained traces of paratoluidin. After I had convinced myself by experiment that the methods of Rosenstiehl,t by treating the oxalates with ether ; and of Beilstein and Kuhlberg,J by precipitating an acetic acid solution of acettoluid with water, — were almost impracticable for large quantities, I tried the method of Schad,§ recommended by Kekule,|| which depends on the crystallization of the nitrates and chlorides, and in this way succeeded in obtaining a liquid toluidin which with acetylchloride gave an acet- toluid melting after one recrystallization from boiling-water at 107°. As some previous attempts to convert orthotoluidin into orthobromto- luol by the usual method through the diazoperbromide had given me as unsatisfactory a yield as that obtained by Wroblevsky,!! I treated this according to a new modification of the process of Hiibner and Majert** for preparing parachlortoluol, which I had found to work admirably in making that substance. This modification was suggested by Victor Meyer's ft method of applying Griess's reaction, and consisted in dis- solving 20 gr. of the orthotoluidin in an excess of hydrobromic acid (boiling-point 125°, prepared according to Naumann t|); the pasty mass was then treated with somewhat more than the calculated amount of solid potassic nitrite, which was thrown in in small portions at a time, the fiask being corked after each addition, and shaken until all the red fumes were absorbed ; after the last portion of nitrite had been added, the greater part of the liquid was distilled off, and the resi- due then treated again in the same way. The distillate consisted of dilute hydrobromic acid and a heavy oily liquid which was separated with a drop-funnel, washed with potassic hydrate solution until the odor of kresole was removed, then with water, and finally dried and rectified ; in this way 40 grammes of orthotoluidin gave 29 grammes of crude

* Wroblevsky, Ann. Chem. Pharra., 168, p. 162.

t Rosenstiehl, Zeitschr. Chem., 1868, p. 557, 666.

t Beilstein, Ann. Chem. Pharm., 156, p. 75.

§ Schad, Ber. D. Ch. G., 1873, p. 1361.

II Kekule, Ber. D. Ch. G., 1874, p. 1006. IF Wroblevsky, Ann. Chem. Pharm., 168, p. 171. ** Hiibner and Majert, Ber. D. Ch. G., 1873, p. 794. tl V. Meyer, Ber. D. Ch. G., 1875, p. 1074, note. tt Namnann, Ber. D. Ch. G., 1876, p. 1574.

OP ARTS AND SCIENCES. 217

orthobromtoluol, and 24 grammes of this gave on the first fractioning 19 grammes of a colorless liquid boiling between 179^ and 182° ; that is, about thirty-six per cent of the theoretical yield, whereas the diazoper- bromide furnishes under the best conditions only ten per cent. The new method has the further advantages of taking much less than half the time occupied by either of the old ones, and the product is not contaminated with the nitro compounds which compelled Hiibner and Majert to reduce before rectifying. Von Richter * has also obtained tetrabrombenzole by the action of nitrous anhydride on a mixture of tribromaniline with hydrobromic and glacial acetic acids ; he ascribes the reaction to the presence of the negative atoms, and announces his intention of trying similar experiments with compounds containing fewer bromine atoms or nitro groups ; that the reaction is not due to the presence of such negative radicals is proved by the previous researches of Hiibner and Majert, which he seems to have overlooked, and the results given above. I should not have intruded on Von Richter's field of work, had it not been necessary for me to obtain the orthobromtoluol, but I felt the less hesitation in doing so, as I am unable to see that his method differs in any essential particular from that of Hiibner and Majert, published nearly two years before the appearance of his article.

The orthobromtoluol was converted into orthobrombenzylbromide by treatment with bromine in the way described under the para com- pound. The purification of the substance was a matter of some diffi- culty, as it seemed to be completely decomposed by rectification, and converted into the alcohol by distillation with steam ; the method finally adopted was distillation in a stream of the vapor from aqueous hydrobromic acid, as described under the metabrombenzylbromide ; the first fifth of the distillate was rejected to make sure of the absence of orthobromtoluol ; that which came over later was washed till it ceased to give an acid reaction, and then dried in vacuo. In this way, 17 grains of pure orthobrombenzylbromide were obtained from 18 grains of orthobromtoluol.

Its purity was established by the following bromine determina- tion : —

0.5035 gr. of substance gave after ignition with CaO 0.7608 gr. of

AgBr.

Required for C-HgBro. Found.

Bromine 64.0 64.30

* Von Richter, Ber. D. Ch. G., 1875, p. 1428.

218 PROCEEDINGS OF THE AMERICAN ACADEMY

A number of bromine determinations made in products from •distillation with steam gave invariably results which were below the theory.

Properties. — It forms a pale yellow oil (the color is undoubtedly due to a trace of some impurity), with an agi'eeable odor, somewhat resembling that of parabrombenzylbromide, and an action on the mucous membrane even more violent than that of the preceding com- pounds ; its boiling-point seems to lie between 250° and 260°, but could not be determined with accuracy because it is decomposed with evolution of hydrobromic acid by boiling. A careful study of the action of heat on this and the allied substances is reserved for a future 2)aper. It does not solidify even at — 15°, can be distilled with steam, burns with the usual luminous green-bordered flame, and does not mix with water, although it imparts its odor to it, but mixes readily with absolute alcohol, ether, benzole, glacial acetic acid, and carbonic disulphide. It does not seem to be attacked by a mixture of potassic dichromate and dilute sulphuric acid, but the alcohol derived from it is completely destroyed by this oxidizing mixture.

ParacMorbenzylhromide,G^Hj^ClCH„Br, was prepared from para- chlortoluol ; melting-jwint, 6°. 5 ; boiling-point, lo8°-161'* ; made by the modification of the method of Hiibner and Majert, already described in connection with orthobromtoluol (see page 216); crude fuming hydro- chloric acid took the place of the hydrobromic acid,and 40 gr. of paratolu- idin were used for each operation ; the oil, after washing with potassic hydrate, proved on rectification to be almost absolutely pure parachlorto- luol, the yield being about 13 gr. It was converted into parachlorbenzyl- bromide in the way already described ; the product of the reaction deposited crystals on cooling, which were drained, and a fresh crop obtained from the mother-liquor by heating it gently for a few minutes in a watch-glass placed on a sand-bath, and then allowing it to stand for some time. The crystals after pressing between filter-paper were purified by crystallization from hot alcohol in corked flasks, as the sub- stance is so volatile that work in open vessels would have been at- tended with great loss ; upon cooling the solution with ice. a little oil separated; and if the liquid was then stirred it immediately became filled with beautiful white needles. On one occasion, the substance was dis- tilled with steam in order to obtain it perfectly white, but this is not to be recommended, as the water left in the distillation-flask deposited long thin ribbons melting at 66°, and therefore evidently the jiarachlorbenzyl- alcohol, while the supernatant liquid contained hydrobromic acid. This

OF ARTS AND SCIENCES. 219

observation furnished a very ueat and convenient way of obtaining the corresponding alcohols from the bromides. (See parabrombenzyl- alcohol in the next paper, p. 221).

The composition of the parachlorbenzylbromide was established by the followino; analvses : —

0.3399 gr. of the substance gave after ignition with CaO 0.5580 gr. AgBr+AgCl.

0.4224 gr. of substance gave 0.6779 gr. AgBr-|-AgCl.

Required for C-HgCl Br. round.

Chlorine and Bromine 56-20 57-20 55-94

Pfoperties. — By slow evaporation of its alcoholic solution, it can be obtained in well-formed colorless prisms, by cooling in radiated bunches of needles often three centimeters lonor ; it has an agreeable aromatic odor, and acts on the mucous membrane more violently than any of the other substances described in this jjaper ; it melts at 48 i'^, sublimes in oily drops, can be distilled with steam, is Tery volatile at ordinary temperatures, so that a crystal will evaporate completely if exposed to the air for a few days, and burns with a flame similar to that of the bromine compounds. It is slightly soluble in water, easily soluble in cold, still more so in hot alcohol, and very readily in ether, benzole, carbonic disulphide, and glacial acetic acid. It is attacked with diffi- culty, if at all, by potassic dichromate and dilute sulphuric acid.

Paraiodbenzylbro>mde,0,.H^ICff,,B)\ WAS made from paraiod toluol ; melting-point, 35° ; prepared according to Koruer* by the action of hydriodic acid on the nitrate of diazotoluol, this last being obtained by Victor Meyer's f excellent modification of Griess's reaction. The introduction of the bromine into the side-chain by treating the boiling substance with bromine vapor was much more difficult than in the preceding cases ; the precautions to be observed were in general the same as those given under parabrombenzylbromide ; but occasionally, in spite of all possible care, a black tarry liquid was the only result of the process. The conditions under which the j^araiodbenzylbromide is formed are now undergoing very careful study by Mr. C. F. Mabery, and the results will be published in his paper upon the paraiodbenzyl compounds. It is a very remarkable fact that in several cases, when the paraiodtoluol was not perfectly pure, the liberation of iodine in considerable quantity was observed during the bromiring; but, in spite of this, the product contained paraiodbenzylbromide, thus apparently

* Kurner, Bull. Acad. Roy. Belg. [2], 24, p. 157. t V. Meyer, Ber. D. Ch. G., 1875, p. lOl-i, note.

220 PROCEEDINGS OF THE AMERICAN ACADEMY

furnishing an exception to the general rule of Beilstein that, in pres- ence of iodine, bromine goes into the benzole ring even at high temper- atures. The product of the reaction, if properly managed, solidified on cooling, and was best purified by standing on paper, which sucked out a quantity of black oil, and afterward by repeated crystallizations from boiling alcohol with the assistance of bone-black.

The composition of the paraiodbenzylbromide was determined by the following analyses : —

0.3721 gr. of substance yielded 0.3773 gr. CO, and 0.0773 gr. of H^O. 0.1774 gr. of substance gave, according to Carius, 0.1285 gr. of Ag. 0.1971 gr. of substance gave 0.2755 gr. of AgBr-|-AgI. There were indications in this analysis that the oxidation had not been complete.

Required for C^HglBr. Found.

Carbon 28-28 " 27-66

Hydi'ogen 2-03 2-31

Iodine and Bromine 69-69 69-47 68-41

100-00 99-44

Properties. — Crystallized from alcohol, it forms flattened needles, which usually have a straw yellow color, but can be obtained white by repeated recrystallization with boneblack. It has an aromatic odor and attacks the mucous membrane much less violently than any of the other substances mentioned in this paper ; this, however, is very probably due to the fact that it is not readily volatile at ordinary tem- peratures ; it melts at 78|° ; does not distil with steam or only with great difficulty ; sublimes in needles ; burns with a luminous green- bordered flame ; and is insoluble in water, almost so in cold, much more soluble in hot, alcohol, but slightly soluble in glacial acetic acid, freely in ether, benzole, and carbonic disulphide. It is not easily attacked if at all by an oxidizing mixture of potassic dichromate and dilute sul- phuric acid.

That all the substances mentioned in this paper contain bromine in the side-chain is proved by the fact that, when boiled with alcoholic sodic acetate, each one of them yields the corresponding substituted beuzylacetate, from which the alcohol can be obtained by heating with aqueous ammonia at 150° to \Q0°. The description of these com- pounds, as well as of certain other derivatives of these substances, will be found in the following articles of this series. For descriptions of the parachlorbenzyl compounds the reader is referred to the papers already cited in the introduction.

OP ARTS AND SCIENCES. 2'Al

SECOND PAPER.

ON PARABROMBENZYL COMPOUNDS. Woodbury Lowery.

Parahromhenzylalcohol^ C^JI^Br CB., Off.) — This substance was most easily prepared by boiling jjarabrorabenzylbromide with water, in a flask with a return-cooler, for two or three days, until it no longer at- tacked the eyes. The reaction ran as follows : C^H^BrCH^Br-l-H^O =:CgH^BrCH.,OH-j- HBr. The presence of the hydrobromic acid was established by treating the acid aqueous filtrate with argentic oxide, when argentic bromide was formed, and the solution became neutral. This method is analogous to that employed by Grimaux * for convert- ing tollylenebromide into tollyleneglycole, except that Grimaux heated the haloid compound with water at 170° to 180'^, while I obtained the alcohol by boiling in a flask with a reverse-cooler. The action of water on benzylchloride at high temperatures has been very thoroughly studied : the first research in this field having been undertaken by Limprichtf as early as 1866, who by heating the two substances to 190° obtained anthracene, a hydrocarbon Cj^Hj^, later identified by Van Dorp t as benzyltoluol, and beuzylether, which he supposed was formed from benzylalcohol ; but neither he, nor Van Dorji, nor Zincke, § who afterward made out the theory of this reaction, men- tioned obtaining benzylalcohol in this way. The alcohol was also obtained in the ordinary way by heating parabrombenzylacetate with aqueous ammonia in a sealed tube to 160*^. The alcohol in whichever way prepared was 25urified by crystallization from boiling watei', and its composition established by the following combustion : —

Required for C.HeBr.OH. Pound.

Carbon 44.92 44.94

Hydrogen 3.74 3.99

Properties. — It forms long elastic transparent colorless flattened needles, with a brilliant pearly lustre and a disagreeable odor; its vapor does not attack the eyes. Melting-point, 69°. It burns with a lumi- nous green-bordered flame, distils with steam although slowly, and is very slightly soluble in cold, more freely in boiling water, easily soluble in alcohol, ether, benzole, and carbonic disulphide.

* Grimaux, Comptes Rend., 70, p. 1363; Ann. Chem. Pharra., 155, p. 338.

t Limpricht, Ann. Chem. Pharm., 139, 303.

X Van Dorp, ib., 169, 207.

§ Zincke, Ber. D. Cli. G., 1874, 276.

222 PROCEEDINGS OF THE AMERICAN ACADEMY

The parahromhenzylacetate ( C^H^Br. CH,, C.ylT.. 0^) was not obtained in a condition pure enough for analysis. On adding water to the alco- holic solution left after boiling parabrombenzylbromide with sodic acetate and absolute alcohol, a more or less dark-colored oil which did not attack the eyes or nose was precipitated : this was dried and frac- tioued. In the first rectification the greater part came over at about 253°, but on fractioning again a considerable portion came over at lower temperatures ; the ofteuer it was distilled, the less constant became the boiling-point, and after several distillations crystals ap- peared both in the residue and distillate, while nearly one quarter of the entire amount came over below 100'^, and another quarter below 247° ; all these fractions attacked the eyes with great energy, whereas the acetate before fractioning did not possess this property ; the crys- tals were little white needles which dissolved readily in ammonic hydrate, and gave a silver salt which was analyzed. 0.2822 gr. of the salt gave 0.1009 gr. of Ag.

Required for CgH^Br. COO Ag. Found.

Silver 35.06 35.75

As the acid melted at 240° to 250°, there could be no doubt that it was parabrombenzoic acid. Unfortunately the amount of parabrom- benzylacetate at my disposal was so small that it was impossible to isolate the other products of this interesting decomposition, and the complete study of this reaction must therefore be postponed until next year, when it will be undertaken in this laboratory.

The acetate before fractioning was an oily liquid heavier than water, having an agreeable odor distantly resembling that of acetic ether, and burning with a luminous green-bordered flame ; the boiling-point could not be determined with accuracy on account of the decomposi- tion described above, but probably lies between 250° and 260°.

ParabrombenzyJcyaiiide (GqH^B): CM^CN), was obtained by boiling- parabrombenzylbromide with an alcoholic solution of potassic cyanide as long as potassic bromide was formed ; on addition of water a yellow oil was precipitated, which deposited crystals after standing for some time, and finally solidified completely. The crystals were drained on filter-paper, and j^urified by crystallization from alcohol. Their com- position was determined by the following volumetric nitrogen determi- nation : —

0.3565 gr. substance gave 20 cc. nitrogen under a pressure of 742 mm., and a temperature of 9^.

Eequired for C^HgBr.CN. Found.

Nitrogen 7.10 6.58

OF ARTS AND SCIENCES. 223

Properties. — The substance sepai-ates from the oil at first obtained, either in flat truncated octahedra with a marked basal cleavage belong- ing either to the tetragonal or orthorhombic system, and having a very strong resemblance to the crystals of ferrocyanide of potassium, or else in flat twins imitating in a very beautiful manner the architectural forms of the trefoil and quatrefoil. These crystals are yellowish white, but the substance is rendered colorless by crystallization from alcohol ; it has a disagreeable odor, does not attack the eyes, melts at 46*^, burns with a luminous green-bordered flame, and is insoluble in water, moderately soluble in cold, freely in hot alcohol, soluble in ether and glacial acetic acid, still more readily in carbonic disulphide and benzole ; by boiling with alcoholic potassic hydrate or heating in a sealed tube with hydrochloric acid it is easily converted into para- bromalphatoluylic acid. It is to be remarked that the chlorbenzyl- chloride, according to the observations of Neuhof,* gave when heated as above with alcoholic potassic cyanide, the amide of chloralphatoluylic acid, the cyanide being obtained only by heating the substances in a sealed tube ; this difference in the behavior under like conditions of two substances so nearly related as chlorbenzylchloride and parabrom- benzylbromide is interesting.

Parahromalphatoluylic Acid (^C^^H^Br.CH.-^COOH). This substance was most easily obtained by heating the cyanide with crude fuming hydrochloric acid to 100^ in a sealed tube. On cooling, the liquid was found to be full of shining flattened needles of the acid, another portion of which had fused on the side of the tube ; this method gave better results more neatly than the saponification with potassic hydrate ;. the acid was purified by recrystallization from boiling water, and its composition established by analyses of its silver and copper salts. (See bilow.)

Properties. — It crystallizes in white glistening flattened needles with but little odor, melts at 114.5", sublimes above its melting-point m little plates, and burns with the usual luminous green-bordered flame. It is but slightly soluble in cold, freely in boiling water, and in alcohol, ether, benzole, carbonic disulphide, and glacial acetic acid. Ammouic and sodic hydrates dissolve it at once, forming the corre- sponding salts; it seems to decompose carbonates, but very slowly and imperfectly : potassic dichromate and dilute sulphuric acid convert it with some difficulty into parabrombenzoic acid melting in an impure state near ■24C.

* Zeitschr. Chem. 1866, p. 653.

224 PROCEEDINGS OF THE AMERICAN ACADEMY

In 1869, Br. Rarlziszewski * obtained a substance which he called parabromalphatoluylic acid, by the action of bromine in the cold upon alphatoluylic acid ; he does not describe it fully, but only says that it crystallizes in prisms melting at 76^, and gives baric and calcic salts crystallizing in warts, and easily soluble in water and alcohol, by oxidizing it with potassic dichromate and dilute sulphuric acid he obtained nothing but parabrombenzoic acid melting at 251*^. He also obtained in the same operation another acid containing bromine, which melted at 99^, and was not further examined. The discrepancy between my results and those of Radziszewski, is j^robably due to the fact that he did not obtain a pure parabromalphatoluylic acid, but that the two acids observed by him were mixtures of para and ortho com- pounds, with perhaps some of the phenylbromacetic acid, CgH-CHBrC OOH, melting-point 82", discovered by him in conjunction with Glaser,t and which he shows in the paper under discussion, is formed from the alphatoluylic acid by the action of bromine at 150'*. The l^resence of a small quantity of orthobromalphatoluylic acid could easily lower the melting-point from 114.^5 to 99°, or even 76" ; and, as it would be entirely consumed by oxidizing with jiotassic dichromate and sulphuric acid, such a mixture would yield only parabrombenzoic acid. On the other hand, my acid being prepared from pure parabrom- beuzyl-bromide, by jDrocesses in which the temperature never rose above 100°, must be perfectly free from isomeres ; and this view is confirmed by the fact that its melting-point is higher than that of the acid obtained by Radziszewski.

Amynonic parahromalphatoluate obtained by dissolving the acid in ammonic hydrate, and driving off the excess of ammonia on the water- bath, crystallized in long curving groups of colorless needles very soluble in water.

Argentic 'parahromalphatoluate ( C^JIJir. CH.^ CO OAg.) was preci- pitated by adding the ammonic salt to argentic nitrate, as a white curdy mass similar in appearance to chloride of silver ; it was washed with cold water, and dried at GO".

0.3106 gr. of the salt dissolved in dilute nitric acid, and precipitated with hydrochloric acid, gave 0.1375 gr. AgCl.

Required for C-Br-HgCO., Ag. Found.

Silver 33.57 33.33

* Radziszewski, Ber. D. Ch. G., 1869, p. 207. t Zeitschr. Chem., 1868, p. 110.

or ARTS AND SCIENCES. 225

It is almost insoluble in water, perhaps a little more soluble in hot than in cold, but it could not be obtained crystallized ; it is readily soluble in dilute nitric acid ; it blackens slightly by exposure to the light, and even at a temperature of 60°.

Ciipric parabromalphatoluate, Cu (C^H^Br CH.,COO),,was precipi- tated as a flocculent bluish green solid, on mixing cupric sulphate with the amnionic salt.

0.3028 gr. of the salt gave 0.05028 CuO.

Required for Cu(r8HeBr.0Jo. Tound.

Copper 12.90 13.24

It is insoluble in water, but soluble in dilute hydrochloric acid.

The baric salt, obtained by neutralizing a solution of the acid with baryta water and evaporating, formed white indistinctly crystalline crusts easily soluble in water.

The calcic salt obtained in a similar way, and also, although very slowly from calcic carbonate and a solution of the acid, appeared in the form of white warts ; which, under the microscope, were seen to be globular groups of sharp needles looking somewhat like a chestnut- bur ; it was easily soluble in water.

The behavior of a solution of ammonic parabromalphatoluate with solutions of" the following salts was also observed : —

Mercurous salts, a heavy flocculent white precipitate.

Mercuric salts, a slight white precipitate.

Plumbic salts, a heavy white precipitate, somewhat soluble in boil- ing water, and separating from this solution in crystalline flocks.

ferric salts, a pale yellow amorphous precipitate, while Chromic, Aluminic, Manganous, Cobaltous, Nickelous, Zincic, and Magnesia salts produced no precipitate.

Triparabrombenzylamine, ( C^H^Br. CK,).. N, was formed even in the cold, when alcoholic ammonia was added to the parabrombenzyl- bromide ; the white crystals which separated in large quantity were washed with water, and then recrystallized repeatedly from alcohol ; in this way the triparabrombenzylamine was easily separated from its brom- hydrate, which is very slightly soluble even in hot alcohol, and two sorts of crystals of the former substance were obtained, one in irregular somewhat bent thick needles, the other in fan-shaped groups of fine needles, both had the same melting-point, seemed to be about equally soluble in alcohol, and mutually convertible under conditions which could not be determined ; it was therefore assumed that they were identical, and this assumption seems to be confirmed by the following analyses : —

VOL. XII. (X. S. IV.) 15

226 PROCEEDINGS OF THE AMERICAN ACADEMY

I. 0.5397 gr. of the thicker needles gave 12 cc. nitrogen, at 757.4 mm., and 20° t.

II. 0.2664 gr. of the fan-shaped crystals gave 5.2 cc. nitrogen, at 763.1 mm. and 17.°5. t.

Eequired for (C^HsBrOgN. Found.

I. II.

Nitrogen 2.67 2.53 2.26

Owing to the small amount of the fan-shaped crystals which could be isolated, I have not been able to establish its composition more securely by a second analysis.

Properties. — It crystallizes either in thick irregular w^hite prisms or fan-shaped groups of white needles, is odorless, melts at 78°-79°, burns with the green-bordered luminous flame belonging to all these compounds, and is insoluble in water, soluble in cold, more so in hot alcohol, freely soluble in ether, benzole, and carbonic disulphide. All attempts to obtain a salt with hydrochloric acid alone, or in connection with platinic chloride were unsuccessful.

Triparabromhenzylamine bromhydrate, (C^.II^Br.CII^).^]}^}! Sr, was formed at the same time as the free base, and separated from it by boiling out the product of the reaction, with alcohol ; the viscous residue left after the removal of the triparabromlieuzylamine by this means was dissolved in ether, from which it crystallized on evaporation.

0.4269 gr. of the substance gave 8 cc. nitrogen, at 767. 7 mm. and 17° t.

0.4713 gr. of substance gave 0.5818 gr. AgBr.

Required for (C^HgBr.JaNH Br. Found.

Nitrogen 2.29 2.19

Bromine 52.54 52.54

Properties. — White odorless plates with a pearly lustre, melting in the neighborhood of 270'-'', is insoluble in hot or cold water, almost msoluble in alcohol even when boiling, soluble although not very easily in ether, gives no double salt with platinic chloride.

The tbrmation of triparabromhenzylamine as the principal product of the reaction is not to be wondered at, as benzylbroraide gives a similar result when treated with alcoholic ammonia (Kekule*). It is not impossible, however, that some di- or even mono-parabrombenzyl- amine bromhydrate was formed, as this would undoubtedly have been

* Kekule Ann. Chem. Pharai., 137, p. 188.

OF ARTS AND SCIENCES. 227

dissolved in washing tlie product of the reaction with water, and this wasli-water was unfortunately lost before it was investigated.

Parabrombe)izyhulphocija)iate {C^H^Br.CH.,SCN) was obtained by boiling the bromide with alcoholic potassic sulphocyanate, and purifying by crystallizing from alcohol at low temperatures. I have but one imperfect sulphur determination of this substance, but have not thought it of sufficient importance to go through the purification of a fresh quantity, which is rendered difficult by its low melting-point, in order to confirm this result.

0.2455 gr. of substance gave .2339 gr. of Ba.SO^.

Required for C^HsBr.SCN. Found.

Sulphur 14.03 13.08

Properties. — It forms white ribbons often 5 cm. long, made up of needles united together laterally, having a strong odor similar to that of benzylsulphocyanate, melting at 25*^, and soluble in alcohol. The surprisingly low melting-point rendered the management of the sub- stance very difficult, and preserving the crystals impossible ; it also — as the benzylsulphocyanate melts at 36°-38°, according to Henry ; * at 41"^, according to Barbaglia f — throws doubt on the analysis given above, and therefore on the correctness of the formula.

Tlie investigation of the pai'abrombenzyl compounds will be continued in this laboratory ; the next portion of the subject to be studied being the action of heat, superheated steam, and sodium on these bodies.

* Henry, Ber. D. Cli. G., 1869, p. 637. X Barbaglia, Ber. D. Ch. G , 1872, p. 687.

228 PROCEEDINGS OF THE AMERICAN ACADEMY

XIX.

CONTRIBUTION TOWARDS THE HISTORY OF THE FLUORIDES OF MANGANESE.

By W. H. Melville.

Presented by the Corresponding Secretary, June 14th, 1876.

The investigation described in this jiaper was undertaken with a view to the re-examination of the fluorides of manganese. Many in- vestigations have been made upon this subject during this century, and necessarily a large amount of fact has been accumulated.

* Berzelius noticed that, on the evaporation of a solution of man- ganous carbonate in hydrofluoric acid, ill-defined crystals were obtained, which dissolved in water only when containing an excess of acid. This amethyst-colored substance he called the proto-fluoride of manganese. He furthermore prepared a fluoride of manganese and potassium by double decomposition of a solution of manganous sulphate and fluoride of potassium. Similarly the soda salt was precipitated. These double fluorides were described as white precipitates, insoluble in water, and soluble in acids.

t When hydrated sesquioxide of manganese is dissolved in hydro- fluoric acid and the solution left to evaporate spontaneously, dark brown prisms crystallize out, which dissolve completely in small quan- tities, but are decomposed by excess of water. When this decom- position ensue*, a basic salt is deposited, while an acid salt remains in solution. A part of the former is redissolved on cooling, if free acid is present. Ammonia precipitates pure hydrated manganic oxide. (Berzelius.)

t A fluoride of manganese has been prepared, in which the Mu and F exist in the ratio 1 : 7 respectively. When a mixture of two parts potassic manganate or permanganate and one part fluor-spar is digested

* Gmelin, vol. iv. Manganese.

t Ibid.

J WGhler, Fogg. 9, 619; Dumas, Ann. Chim. Phys., 3G, 82.

OF ARTS AND SCIENCES. 229

with sulphuric acid in a platinum retort, a yellow vapor, purple in moist air, is evolved. This fluoride having the above ratio cor- rodes glass, and in so doing is resolved into (SiFJ silicic fluoride and (H^MnoOg) permanganic acid. Chloride of calcium exposed to the yellow vapor evolves chlorine. The compound is absorbed by water, forming a purple solution, which contains hydrofluoric and perman- ganic acids. When the solution is evaporated in air, it evolves oxygen gas and hydrofluoric acid vapor, and leaves a brown residue from which water dissolves manganous fluoride, leaving a black insoluble basic salt. The solution dissolves copper, mercury, and silver, with formation of the corresponding fluorides.

* The tetrafluoride of manganese, MnF_,, is produced in solution : (1) when hydrofluoric acid is allowed to act on an ethereal solution of MnCl^ ; (2) when the acid acts on MuOj, in which case all the acid employed cannot be neutralized. The solution decolorizes indigo, and produces colors with anilin and naphthylamine ; but may be preserved in the presence of glucose and gum-arabic. The substance dissolves in alcohol ; decomposes in presence of much water, especially when it is alkaline, peroxide of manganese being formed. When potassic flu- oride is added to the preceding solution, a rose precipitate is formed, which when dried at 100°C yields the formula MuF^2KF. Ammonic fluoride yields a compound of analogous composition. The alkaline fluorides appear to give stability to the tetrafluoride. The potash salt melts, and after lengthened fusion the salt MnF^.iKF is obtained. The solution of tetrafluoride precipitates an alcoholic solution of plumbic acetate. None of these compounds are crystalline. If to a boiling solution of potassic fluoride or ammonic fluoride perchloride of manganese is gradually added, a red powder comes down, the consti- tution of which is represented by the formula MnOF,. This oxy- fluoride and the preceding tetrafluoride are soluble in anhydrous ether. Under the same conditions as above the sesquifluoride of manganese acts in a similar manner, the properties of the compounds thus formed being generally the same. With K^Mn^O^ and hydrofluoric acid, either one or other of the following bodies is obtained: MnF^. 2KF ; Mn^ F,0H-2KF.

t When Mn02 is treated with hydrofluoric acid, brown crystals are sometimes deposited, especially when the mixture has been digested with the aid of heat. The crystals when dried on paper furnish the

* Bull. Chim. Soc. viii. 4.8, NLkles. t Ibid.

230 PROCEEDINGS OF THE AMERICAN ACADEMY

formula MngFg. lOH^O. The substance is soluble in a small quantity of water, but decomposed by an excess into the brown oxide of man- ganese. Its solution forms a red precipitate with potassic fluoride. Dissolves silver, and is decolorized in passing to the state of proto- fluoride.

* A fluosilicate of Mn has been artificially prepared, represented by MnSiFg. 7H^0. Crystallizes in long six-sided prisms, and rhombo- hedrons. Color very light red. When heated, it first gives off seven molecules of water, then gaseous SiF^, leaving MnFg of the same form as the original crystals. Easily soluble in water.

Manganous Fluoride, MnF\ — Owing to the difficulty of obtaining mangauous oxide free from higher oxides, it was found more practi- cable to prepare this fluoride by dissolving the white manganous car- bonate in hydrofluoric acid. The resulting liquid was then evaporated on the water bath to dryness. The fluoride rendered anhydrous by drying at lOO^C. gave by analysis : — •

Found. At. Ratio. Theory.

Mn 58.G8 LOG 59.14

F3 40..57 2.13 40.86

99.25 100.00

Manganese and fluorine were separated by decomposition with a con- centrated solution of potassic hydrate, the hydrate of Mn thus formed converted into pyrophosphate, and the fluorine in the filtrate precipi- tated as calcic fluoride.

Properties. — Color white, shading faintly into pink. Structure crys- talline, but indistinct. Insoluble, or sparingly soluble, in water and alcohol. Decomposed by the fixed alkalis and their carbonates. Dis- solves in mineral acids, but in no case evolves hydrofluoric acid vajjor ex- cept when treated with concentrated sulphuric acid. (It may be well to notice once for all that concentrated sulphuric acid invariably decom- poses fluorides with evolution of hydrofluoric acid.) Dissolves in water containing free HF. Not decomjjosed by water, or by exposure to air. At red heat fuses to a dark brown mass with loss of fluorine.

Manganous Fluoride and Hydrofluoric Acid, MnF.^. 2)HF. ^dH.^0. — When the anhydrous MnFg is dissolved in aqueous hydrofluoric acid, and the solution evaporated in vacuo over snlphuric acid, crystals containing free hydrofluoric acid are deposited. Also prepared directly

* Gmelin, vol. iv. Mn. Berzelius.

OF ARTS AKD SCIENCES. 231

from manganons carbonate. The crystals freed from hygroscopic moisture gave the following numbers : —

	Found.	At. Ratio.	Theory.
Mn	17.90	.32	17.46
F5	29.16	1.54	30.16
H3			.96 1
QH^O			51.42 i

52-38

100.00

Tlie salt was dissolved in water, the manganese precipitated with a solution of sodic carbonate, and, after filtration, fluorine was thrown down by calcic chloride.

Properties. — Colorless, sometimes light pink. Crystals are trans- parent long prisms of the trimetric system. Soluble in water, giving acid reaction. Soluble in acids. Effloresces in air ; when heated at lOO'^C, changes into the simple MnFg.

Double Fluoride of Manganous Oxide and Potassium, MnF^. KF. — On the addition of an excess of potassic fluoride to a solution of manganous chloride, an immediate separation of an insoluble compound results. A double decomposition ensues, which is expressed by the reaction : —

MnCl2 + 3KF = MnF2. KF + 2KC1.

The precipitate collected on a filter is washed with water, then with alcohol, and subsequently with ether. Alcohol and ether are employed to remove the last traces of water, same result : —

Found.

Mn 36-23

K 26-06

Fg 37-71

Heating	at	100° produces the
At. Ratio.		Theory.
-66		36-40
•66		25-87
1-98		37-73

100-00 100-00

The method used in analysis was based upon the conversion of the double fluoride into a mixture of sulphates of manganese and potas- sium. The weight of the sulphates being known, as also that of the manganese therein contained, the percentages of the metals were easily calculated, while the fluorine was inferred by difl^erence.

Properties. — Flesh colored. Crystalline. Insoluble in water and alcohol. Not decomposed in air and water. Dissolves in acids. Fuses at red heat.

232 PROCEEDINGS OP THE AMERICAN ACADEMY

This fluoride was first prepared by Gay-Lussac and Thenard, and afterwards described by Berzelius as a compound of manganese and potassium ; but the latter established no ratio between the constit- uents.

An analysis of the soda salt which is precipitated under the same conditions will by analogy furnish the formula MuFg. NaF.

Another double fluoride of manganese and potassium has been ob- tained by adding potassic fluoride to a solution of MnF.,. 3HF. A white crystalline precipitate is immediately thrown down, which anal- ysis shows to contain Mn and K in the ratio 1 : 4 respectively. This double fluoride has identical properties with the preceding.

Tetrajiuoride of Manganese, 3LiF^. AK^O. — (1) A black oxide of manganese was prepared by exposing manganous carbonate to a dull red heat for a considerable time. This oxide was proved to be

Mnp., : -	—
		Found.	At. Ratio.	Theory.
	Mn^	69.62	1.26	69.60
	O3	30.38	1.89	30.40

100.00 100.00

This oxide dissolves readily in hydrofluoric acid with the aid ot heat, and the deep red solution, when evaporated to the crystallizing point, deposits crystals on cooling. A larger crop of crystals is ob- tained by carrying the solution to dryness in vacuo. (2) Pure per- oxide of manganese is dissolved in hydrofluoric acid under j^ressure with the aid of heat. On evaporating the solution red crystals are obtained.

In the following analysis, Mn was estimated, and the combined weight of fluorine and water inferred from the loss. The water was then determined in a second portion of the material by ignition with plumbic oxide. The fluorine was thus indirectly ascertained: —

	Found.	At. Ratio-	Theory.
Mn	27.22	.49	27-10
F4	36.82	1.94	37-43
4H,0	35.96	1.99	35-47

100-00 100-00

Properties. — Color, red by reflected, purjile by transmitted, light. Crystallizes in the monoclinic system in rather long, narrow prisms. These prisms consist in basal planes at the end of the ortho and klino

OP ARTS AND SCIENCES. 233

diagonals, and in four jilanes constituting a vertical dome ; they ter- minate at one end in two planes which form one-half of a klino dome. Partially decomposed by large quantities of water and alcohol ; com- pletely by a solution of a fixed alkali into the brown hydrate of man- ganese and fluoride of the alkali. Soluble in acids ; partially soluble in anhydrous ether. Insoluble in benzol and toluol. When the solu- tion of this fluoride before crystallization is boiled, a dark brown substance is deposited, which evolves HF vapor with suliihuric acid. The crystals retain their crystalline form, but turn dark brown on exposure to air or the temperature of 100°C. This brown sub- stance is probably an oxyfluoride, in which two or a multiple of two atoms of fluoride in the original fluoride are replaced respectively by one or more atoms of oxygen.

I can account for the formation of MnF^ instead of Mn^Fy from the sesquioxide in no way except by assuming either that during the pro- cess of evaporation the sesquifluoride breaks up into tetrafluoride, or that the existence of a sesquifluoride is impossible.

Double Fluoride of Peroxide of Manganese and Ijptassium, 3fnF^. 2KF. — To a moderately concentrated solution of MnF^, potassic fluoride dis- solved in water is added in excess. Care must be taken that the solu- tion of potassic fluoride is concentrated, otherwise the tetrafluoride of manganese will be decomposed. A rose-colored precipitate imme- diately separates, which when dried at 100°C. presents the following composition : —

	Found.	At. Ratio.	Theory.
Mn	22.00	.40	22.25
K,	31.82	.81	31.65
Fe	46.18	2.43	46.12

100.00 100.02

The analysis was conducted in the same manner as that of the for- mer double fluorides.

Properties. — Rose colored. Under the microscope exhibits traces of crystalline structure ; form indistinct. Decomposed by water, but not so readily as the tetrafluoride. Soluble in acids. Stable in air. Fuses to a blue mass, which on cooling resumes its original color.

A fluoride of manganese was prepared, in which the ratio between manganese and fluorine was found to be 1 : 8 respectively. This fluo- ride, however, requires further study ; and it is hoped that, if the above ratio shall be proved beyond question to exist, the exact relation and disposition of the atoms will be determined.

234 PROCEEDINGS OF THE AMERICAN ACADEMY

Finely pulverized K„MnoOg was dissolved in aqueous hydrofluoric acid, and the solution subjected under pressure to the temperature of 100°C two or three hours. The red solution was then evaporated in vacuo. Claret-red prisms belonging to the trimetric system were deposited, in which the ratio of the constituents — Mn, K, and F — was not determined. Consequently this substance also remains for future investigation.

OF ARTS AND SCIENCES. 235

XX.

ON SOME ALG^ NEW TO THE UNITED STATES.

By W. G. Farlow.

Presented May 9, 1877.

The present paper is a supplement to one presented to the Academy, March 9, 1875 ; and our object is to com[)lete, as far as possible, the list of marine algiB found in the United States. We include a number of species which were referred to in a paper in the " Report of the United States Fish Commission" for 1875, which was intended to serve as a guide to the collection of algse in the Government Building at the Centennial Exhibition. Some species of New England, which are soon to be described at length in another publication, are here mentioned only by name.

Of the species added to our marine flora, a number were collected at Key West and the Tortugas by Mr. F. W. Hooper, in the winter of 1876. New Californian species have been received from Dr. Anderson, of Santa Cruz; Mr. Cleveland; Mr. Hemphill, of San Diego; and Miss Lennebacker, of Santa Barbara. Several interesting forms were collected by Dr. Edward Palmer at the island of Guadeloupe and in the vicinity of San Diego, and Prof. D. C. Eaton, of New Haven, has kindly communicated species from both east and west coasts.

FLORIDE^.

Dasya subsecunda Suhr. K.tz. Tab. Phyc, V. XIV., PI. 78 a. b. D. CalUthamnion Harv. Farlow, Proc. Am. Acad., 1875, San Diego, Cleveland ; Santa Barbara, Dr. Dimmock. This minute species, which is not uncommon in Southern California, has the habit of C. Wurde- manni Bail., but the ramuli are robust and more or less secund, while in C. Wvrdemanni they are attenuated and dichotomous, bi-anching at wide angles. We formerly erroneously referred this species to D. Cal- Uthamnion Harv., being led to that conclusion by tlie fact that a cross- section of the stem showed four cells around a central cell, as was also the case with an authentic specimen of D. CalUthamnion Harv. Far-

2C6 PROCEEDINGS OF THE AMERICAN ACADEMY

ther study shows, however, that the number of cells seen in cross- section varies from four to eight ; and it may be remarked that, in most of the species belonging to the subgenus Stlchocarpus, the number of cells is too inconstant to constitute a specific character.

Dasya trichoclados 3IerL var. Oerstedi, J. Ag. = Dasya lopho- clados Mont., Ner. Am. Bor. II. p. 65.

T^NiOMA Clevelandii, n. sp. fronde capillacea erecto-cpespitosa ad 4 pollicares ; ramis flexuosis irregulariter pluries pinnatis, ramulis ad basem contractis, ultimis subulatis incurvatis ; articulis subcom- pressis, 4 siphouiis fere ecorticatis, 2 siphoniis lateralibus marginatis ; stichidiis nunierosis sparsis vittfeformibus tetrasporas oppositas foven- tibus in apicem subacutum abeuntibus. — San Diego, Cal., INIr. D. Cleve- land. — But two species of this genus are as yet known, T. perpusillum Ag., found by Liebmann on the west coast of Central America, and T. macrourum Thur., found by Schousboe at Tangier. We should naturally expect the first-named species to occur at San Diego ; but, as it is de- scribed by Agardh as closely resembling CalUthamnion Rothii in habit and mode of growth and having subfesciculate stichidia, it would hardly seem as though the plant collected by Mr. Cleveland, which has scat- tered stichidia, is four inches high, and has a striking resemblance to Griffithsia tenuis Harv., could belong to the same species. The specimen sent by Mr. Cleveland is unfortunately broken off near the base ; but, judging from what was sent, there seems to be no creeping primary filament. From T. macrourum the present species differs in having the stichidial branches terminate in a more or less acute apex instead of two hairs. When seen in front view, the frond shows a series of articulations, each of which is composed of three subequal cells bordered on both sides by a wider cell. A cross-section is rather narrowly elliptic, and shows four subequal cells arranged round a central cell, as in many species of Polysiphonia ; but each of the cells lying in the longer axis of the ellipse has a cell in contact with it on the outer side and of about the same size as itself, so that the short axis of the ellipse is composed of two, and the long axis of four, cells besides the central cell. In the lower part of the frond, the angles between the primary cells are filled with a small but irregular number of secondary cells.

Polysiphonia senticulosa Harv. This species, described in the Jour. Proc. Linn. Soc, Vol. VI. No. 24, p. 169, is apparently common along the whole Californian coast. It admits of question whether the species should not be considered a variety of Pol. urceolata.

Polysiphonia secunda Ag. Under this species is included by

OF AETS AND SCIENCES. 237

Agardh PoIi/sipJwnia pecten- Veneris, var. B. Harv,, of the Ner. Am. Bor. II., p. 4G. The question then arises, "VVliat is the plant de- scribed in the Ner. Am. Bor. 11., p. 35, as having but four siphons, and referred to Pohjsiphonia secunda IMont., said by Montagne himself, Syll. Crypt, p. 424, to be the same as P. seciindn Ag.

PoLYSiPHONiA PENXATA Ag. To this species was doubtfully re- ferred a small Polysiphonia from San Diego, which seemed not uncom- mon on Gelidium cartilagineum and other large Floridece. The specimens should have more properly been referred to Polysiphonia verticillata Harv. A single specimen received from Mrs. T. M. Allen, collected at Santa Barbara, Cal., does not seem to belong either to P. verticillata or to P. dictyurus, if the figure in the Tab. Phyc. is to be trusted, and may belong to Pohjsiphonia pennata.

Polysiphonia thyrsigera J. Ag. Key West, Mr. F. W. Hooper ; Nassau, Miss Minns.

Polysiphonia dictyurus J. Ag. San Diego, Cal., Mr. D. Cleve- land. A single specimen, which we supposed to be new and to which we gave the manuscript name of P. Clevelandii, seems to be a variety of P. dictyurns, in which the ramuli are very regularly pinnate, and the ultimate ramuli all beautifully recurved. The number of cells in cross-sections of the larger branches is ten.

Acanthophora muscoides Ag. The true A. Delilei has never been found in this country. The species given by Harvey with that name, in the Ner. Am. Bor., is Acanthophora muscoides, Ag. and the name A. Delilei should have been suppressed in the Proc. Am. Acad., 1875.

Ricardia Montagnei Derbes. San Diego, Cal., Mr. Cleveland ; Santa Barbara, Miss Lennebacker. This curious little plant is rarely over quarter of an inch liigh, and grows in small clusters on the con- cave tips of species of Laurencia. The Californian specimens on L. virgata resemble, in all I'espects, those from the Mediterranean, except that tliey are rather more luxuriant.

Laurencia Brongniartii J. Ag. Key West, Mr. F. W. Hooper. One of the more beautiful species of the genus, and which bears a striking resemblance to Amansia multijida.

Laurencia tuberculosa J. Ag. Prof. Agardh regards Lauren- cia gemmifera Harv., as a variety of this species.

Laurencia intricata Lam. Key West, Mr. F. W. Hooper. A species forming dense cushions, and resembling closely the figure in Kiitz. Tab. Phyc, Vol. XV., tab. 61, was collected by Mr. Hooper.

Laurencia spectabilis, Post. & Rupr. Prof. Agardh is inclined

23,8 PROCEEDINGS OF THE AMERICAN ACADEMY

to keep this sjoecies distinct fi-om L. pinnatijlda, with which it was united by Harvey.

Erythrocystis Grevillei J, Ag. Epicr. = Lomentaria'? saccata J. Ag. Sp. p. 738.

Delesseria Woodii J. Ag. Santa Barbara, Cal., Miss Lenne- backer.

NiTOPHYLLUM viOLACEUM, J. Ag. Epicr. This is the species de- scribed in the Ner. Am. Bor. and Proc. Am. Acad., 1875, as Nitcphyl- lum laceratum Grev.

NiTOPHYLLDM LATissiMUM Harv. Under this species should be included Nit. areolatum Eaton mscr. of the Rep. U. S. Fish Comm., 1875.

NiTOPHYLLUM MULTiLOBUJi J. Ag. Epicr. Golden Gate, Cal., Berggren. We have never seen this species, which, according to Prof. Agardh, differs from all other species in having large transverse sori.

NiTOPHYLLUM SPECTABiLE Eaton. California.

EuCHEUMA ACANTHOCLADUM J. Ag. Epicr. ^= Chry^ymenia acan- thocJada Harv.

Rhabdonia ramosissima J. Ag. Epicr. == Chrysymenia ramosis- sima Harv., Ner. Am. Bor.

The species of CoralUnece found on the coast of the United States are in a state of great confusion, and it will probably be some time before they are clearly made out. One great difficulty in the way is the uncertain characters by which the genera are at present constituted. In this connection, we only wish to call attention to the forms found on our coast, giving the names under which they are commonly de- scribed, without meaning to indorse the specific value assigned by dif- ferent writers. We are greatly indebted to Dr. Ed. Bornet for notes and suggestions with regard to our species, especially the Gorallineae and Sqnumarice.

CoRALLiNA PiSTiLLAETS Mont. A small Coralline, nearly related to this species, perhaps identical with it, has been found at Santa Cruz, Cal., by Dr. Anderson.

Amphiroa Orbigniana Harv. The common Amphiroa from California, which is usually distributed as Amphiroa Californica, D.cue., does not, according to Dr. Bornet, conform to the type of that species, but more properly belongs to Ainpk. Orbigniana. Harv. The species is incorrectly referred in Proe. Am. Acad., 1875, p. 364, to Arthrocardia frondescens, Aresch., to wliich some of the broader forms have a not very remote resemblance.

OF ARTS AND SCIENCES. 239

Amphiroa vertebralis D.cne. This form, collected in Oregon by Rev. E. Hull, in 1871, resembles the species described by Postels and Ruprecht as Amph. tuberculosa, Illust. Alg., p. 20, T. XL. fig. 100, and it may be asked whether it is not really the same species.

Amphiroa Tribclus Lam. A West-Indian species also found at Key West by Mr. F. W. Hooper.

Amphiroa fragilissima Lam. In the Ner. Am. Bor., Harvey mentions both Amph. fragilissima Lam., and Amph. dehilis K.tg., as found at Key AVest. The Amph. debilis of Kiitzing is, however, only a synonyme for Amph. fragilissima Lam., while the plant refen-ed to by Harvey is a much larger species, possibly Amph. cuspidata Lam.

LiTHOTHKix AsPERGiLLUM. J. E. Gray. San Diego, Cal., Mr. Cleveland ; Santa Barbara, Miss Lennebacker ; Santa Cruz, Dr. Ander- son, This species seems to be tolerably common along the California coast. It was quoted in the Rep. U. S. Fish Com., 1875, under the name of Amphiroa nodulosa K.tg. Judging from the figure in the Jour. Bot., 1867, there can be no doubt that this is the species there described ; but it is difficult to understand the grounds for separating the genus Lithothrix from Amphiroa.

Melobesia amplexifroxs Harv. A species which appears com- mon on Zostera, Gelidium cartilagineum, and other algte from Santa Cruz, Cal., southward. The conceptacles are immersed so that the frond appears punctate.

Melobesia Lexormandi Aresch. San Diego, Cal., Mr. D, Cleve- land. A Melobesia occurs at Wood's Hole, Mass., which is probably also to be referred to this species.

Melobesia Lejolisii Rosanoff. Common on Zostera at Nahant, Mass.

LiTHOTHAMXiox POLYMORPHUM Aresch. Very common from Boston northward, forming purple crusts on the rocks in tide pools. Also found at San Diego, Cal. ^

LiTHOTH AMNION FASCICUL ATC.M Aresch. Dredged in several places near Eastport, Me.

Petr'>cklis cruenta Ag. Common on rocks from Nahant, Mass., northward ; also at Santa Cruz, Cal. It has, as yet, been found only with tetraspores.

Peyssonnklia rubra (Grev.) J. Ag. Tlie species referred to in the Rep. U. S. Fish Comin , 1875, under the name of P. atro-purpurea Crn., belongs more properly to P. rubra.

Peyssonnelia Dl'byi Crn. San Diego, Cal., Mr. Cleveland. Although P. rubra is common at Key West, it is douDtful whether

240 PROCEEDINGS OF THE AMERICAN ACADEMY

P. Duhji occurs there. "We have also found sterile specimens of a Peyssonnelia at Eastport, Me., which is pi'obal}ly referable to P. Duhyi. P. imbricata, K.tg., in the absence of fruit, will remain a doubtful species.

Cruoria purpurea, Crn. San Diego, Cal., Mr. Cleveland.

Cruoriella armorica, Crn. San Diego, Cal., Mr. Cleveland.

Galaxaura (Microthoe) lapidescens Lam. Key West, Mr. F. W. Hooper.

Galaxaura rugosa, Kiitz. Key West, Mr. F. TV. Hooper.

Liagora farionicolor, and L. Cayohuesonica Melville, Jour, of Bot., Sept., 1875, do not seem to be admitted as species by Agardh in his Epicrisis.

Nemalion? Andersgnii, n. sp. frondibus congregatis lubrico-car- tilagineis simplicibus vel sparse furcatis ; raniis primura subcompressis solidis demum cavis cylindraceis ad 6-8 pollicares altitudine, plerumque subjequalil)us ramulis dense cinctis ; ramulis simplicibus vel furcatis ; antherozoideis ad cellulas externas fasciculatis ; cystocarpiis ? — Santa Cruz, Cal., Dr. C. L. Anderson. — This species, first found by Dr. An- derson, is variable in appearance. AYhen young, the fronds are solid, and consist of an undivided axis, from which ai'e given off short lateral branches in all directions. When older, the main axis forks once or twice, as do also the ramuli ; and, still later, the main axis becomes swollen and hollow, and not unfrequently perforated. The substance is always lubricous and cartilaginous, and the color is a blackish-purjile. The frond is composed of closely interwoven longitudinal filaments, from which are given off at right angles dichotomous moniliform fila- ments. We liave never found the cj^stocarps or tetraspores of this species, and consequently there must remain some doubt with regard to the genus. Antherozoids are abundant, and nearly cover the surface of some specimens. As we have not been able to find traces of cysto- carps, it is probable that the present species is dioecious, and, in ihat respect, different fi-om other sjiecies of Nemalion. In aspect it not unfrequently resembles a coarse Ghordaria, and in its later stages bears a certain resemblance to some forms of Halosaccion rameMaceum. As ordinarily seen, it is easily recognized by the rather thick main axis, closely beset with short ramuli of nearly equal length. The ramuli are often distorted by the parasite Strehlonema fasciculatnm Thuret. Np- malion virens, Ag.. of the Pacific coast of Mexico, might be expected to occur in California. The description of that species, however, does not at all apply to the plant found by Dr. Anderson.

Plocamium violaceum, n. sp. froude anguste liiieari ad 5-6 pol-

OF ARTS AND SCIENCES. 241

Hcares altitudine irregiilariter pinnata ; ramis ecostatis prrecipiie ad apices Hexuosis ; piniiis alterne 2-4, plerumque 3, pinna inforiori subuli- formi sxpe recurvata pinnas superiores decomposito-pinnatas superante; spluerosporis biseriatim ad 2-3 furcatos apices ordinatis. Color pur- pureus. — Santa Cruz, Dr. C. L. Anderson ; San Diego, Mr. D. Cleveland. — Tlie present species is said by Dr. Anderson to inhabit rather deep water. It resembles Plocamium coccineum in having the pinna; arranged alternately in thi-ees and fours, but differs in having the lower pinna larger than the others and slightly recurved. In the length of the lower pinna, the species approaches P. cornutum which, however, does not have pinnae arranged in threes or fours. In the flexuous character of the branches, the species resembles PI. coc- cineum var.jlexuosum Harv., which is considered by Agardh a variety of PL lepophyllum Kiitz. We have compared the present species with specimens of PI. coccineum var. Jlexuosum, named by Harvey, and find it to differ in color and substance and in the large lower pinna. The plant adheres slightly to paper, and is of a dark purple color, un- usual in species of the genus.

CoRDTLECLADiA CONFERTA (Schousb.) Mont. San Diego, Cal., Mr. Cleveland ; Santa Barbara, Miss Lennebacker. jVot an uncom- mon species of Southern California, but sometimes distributed as a species of Gracilaria.

Sarcophyllis Californica J. Ag. In his Epicrisis, Prof. Agardh separates this species from aS^. edulis, to which species California speci- mens had been previously referred.

Farlowia crassa J. Ag. Santa Cruz, Cal., Dr. Anderson; Ore- gon, Rev. E. Hall.

Farlowia cojipressa J. Ag. Santa Cruz, Dr. Anderson ; Santa Barbara, Miss Lennebacker ; San Diego, Mr. Cleveland.

Cryptosiphonia Woodii J. Ag. Santa Cruz, Cal., Dr. Anderson.

Kallymenia Californica, n. sp. fronde carnosa radiatim pro- lifera demum irregulariter fissa inferiori parte costata ; prolificationibus flabelliformibus in stipitem basi attenuatis stepe phyllis marginalibus minutis fimbriatis ; cystocarpiis in media fronde nuinerosis immersis. — Santa Cruz, Cal., Dr. Anderson. — This species was found by Dr. An- derson thrown up from deep water in company with Constantinea Sitchensis, which it resembles in texture and color. In fact, until the tetraspores have been discovered, it will not be possible to affirm that this is not a Constantinea, although the absence of a distinct stipe would lead one to place the plant in the genus Kallymenia rather than Con- stantinea. We first supposed the plant to be Kallymenia^ phyllophora

VOL. XII. (n. S. IV.) 16

242 PROCEEDINGS OP THE AMERICAN ACADEMY

J. Ag. ; but having sent a specimen to Prof. Agardh, he has decided that it is not the species prevously sent him from Vancouver's Island. The fronds are fixed by a disk, from which they rise, or more probably expand out horizontally, for five or six inches. As most commonly seen, they resemble a species of Opuntia with fan-shaped or obovate joints, which are usually fringed with small leaflets on the margin. All tlie lower parts are distinctly costate. The color is a deep I'ed, which becomes very dark. The cystocarps are densely scattered in the central part of the upper portion of the frond. In none of the specimens which we have received is the fruit ripe ; but, using the common exjiression adopted in this order, there is a compound nucleus, not a simple one, as found in Prionitis^ Schizymenia, and other allied genera.

Phyllophora Clevelandii Farlow. Tetraspores in oval shaped nemathecia in the upper part of frond.

Gymnogongrus leptophyllus, Ag. California, Dr. Anderson. Under this name Prof. Agardh distinguishes the species commonly distributed as Gymnogongrus Griffithsice of our west coast, in which the cystocarps are immersed, or nearly so. There is still another Gymnogongrus, not uncommon in California, in which the cystocarps project hemispherically on one side of the frond, and which, with little doubt, is G. tenuis, Ag. G. linearis Ag. was accidentally omitted from the list in Proc. Am. Acad., 1875.

Chondrus canaliculatus Ag. California in several places. It is doubtful whether G. qfftnis Harv. is really distinct from this species.

Cryptonemia obovata J. Ag. Santa Cruz, Cal., Dr. Anderson.

Crytonemia dichotoma J. Ag. A single specimen of what seems to be this species was collected by Mr. D. Cleveland at San Diego.

Prionitis Andersoniana, Eaton mscr. Santa Cruz, Dr. An- derson.

Prionitis ? Clevelandii, n. sp. fronde coriacea substipitata repe- tite flabellatim prolifera inferiori parte subcostata demura irregulariter perforata ; prolificationibus a disco aut intra margiuem exeuntibus ; cystoearpiis — ? — San Diego, Mr. D. Cleveland. — Of this striking species we have seen but a single steiile specimen, from which it is of course impossible to determine the genus with certainty. We at first supposed it to be the same as the plant to which we have given the name of Kalbjmenia Galifornica. The resemblance, however, is only external, for the structure of the frond is exactly that of Prionitis. If the fruit of the present species should show that it really belongs to

OF ARTS AHB SCIENCES. 243

the genus Prionifis, it may be readily distinguisliefl by its flabellate habit. In some respects, it resembles in form Iridcea lacera, Post, and Rupr. Ill, p. 17.

SciiiZYMEXiA ? COCCINEA Harv. Santa Cruz, Cal., Dr. Anderson ; San Diego, Mr. Cleveland. To this species, described in Jour. Proc. Liunean Soc, Vol. VI., No. 24, is doubtfully assigned several large specimens from California.

Grateloupia Cutleri^, Binder. Santa Cruz, Cal., Dr. Anderson ; San Diego, Mr. Cleveland. This very variable species has undoubt- edly received several specific names, and it must be said that even Gr. Gibbesii Harv., of our southern coast, is not decidedly distinct. If one is to found species of Grateloupia on the outlines of the frond alone, it will be easy to make almost any number of species out of Gr. Cutlerice.

Haltmenia decipiens, J. Ag. Key West, Mr. Hooper.

Nemastoma Californica, n. sp. fronde gelatinosa roseo-purpurea tereto-compressa basi alternata irregulariter pinnata ; pinnis pinnatis ; pinnulis ultimis subuliformibus ; cystocarpii§ in corticali parte frondis numerosis. — Santa Cruz, Dr. Anderson ; Santa Barbara, Miss Lenne- backer. — This plant, which we formerly referred to Halymenia ligu- lata under the name of variety Californica, differs in the structure of the cortical filaments from. any species of Halymenia ; and granting that the genera Halymenia, Nemastoma, Gloiosipho7iia,and Calosiphonia, are nearly related to one another, the present species, owing to the fact that the central siphon can be traced only at the tips of the branchlets, cannot well be included in GloiosipJionia or Oalosipho7iia, nor in Halymenia, since the cortical filaments are not united into a membrane, as is more or less the case with the species of that genus. In aspect the plant resembles rather closely Gloiosiphonia capillaris, and some of the older specimens are not very unlike narrow forms of Halymenia ligulata. It seems to be a connecting link between the genera Gloiosi- phonia and Halymenia as far as the structure of the frond is concerned. When freshly mounted, the species is of an agreeable purplish-rose color ; but, as usually received from California, it is brownish, and dis- torted by too heavy pressure.

Griffithsia opuntioides Ag. Santa Cruz, Cal., Dr. Anderson.

Griffithsia Bornetiana Farlow. In the Ner. Am. Bor., Harvey refers the common Griffithsia of the North American coast to Griffith- sia corallina, Ag., with some doubt, and describes a variety globifera and a variety tenuis. In his Epicrisis, Agardh adopts the manuscript name of Harvey, G. globifera, to designate the American species.

244 PROCEEDINGS OF THE AMERICAN ACADEMY

Harvey states, however, that his name, G. ghhifera, was only intended to apply to what he afterwards called a variety of G. corallina. We have ascertained by examination of the living jDlant, which is common in Long Island Sound, that there is but one species which comprises all the forms described by Harvey under the name of Griffithsia in the Ner. Am. Bor. The so-called var. ghhifera is merely the male plant, of which the terminal cell is enlarged and globose, and has the anthero- zoids borne in the form of a cap on the summit, in which respect it differs from any other species of the genus. The male plant is always shorter and stouter than the female plant. The var. tenuis of Harvey is usually tetrasporic, and the tetraspores are borne in whorls of sev- eral consecutive joints. In another place we shall have more to say on the present species ; and we only need remark, iu this connection, that, under G. Bornetiana, we include all the forms erroneously referred by Harvey in the Ner. Am. Bor. to Griffithsia corallina, and by Agardh in his Epicrisis to G. glohifera^ Harv., which was the name applied by Harvey himself to what is really only the male plant.

Callithajinion Lejolisea, n. sp. fronde minuta repente ad nodos Amphiroce parasitica ; filis verticalibus superne nudis in parte infe- riore ramulosis ; antheridiis ovalibus ad ramos inferiores terminalibus ; cystocarpiis (favellis) ad ramos inferiores terminalibus ; sphserosporis triangiilatim divisis in ramulis lateralibus terminalibus. This very small species of Callithamnion, which is seldom an eighth of an inch high, was found growing on the joints of an Amphiroa received from San Diego, Cal. It is probably not rare on the coast of California, but from its small size escapes detection. It resembles i:)erfectly, ex- cept in the cystocarps, Lejolisea Mediterranean which grows upon Udotea Jlahellata. In both species the frond is procumbent and attached by disk-like cells, and the erect filaments give off at the base a few lateral branches, upon whose tips the organs of fructification are borne. In both species the antheridia are oval, and the tetraspores tripartite and more or less clustered. In the one case, however, the fruit is a true favella, and the species must be considered a true Callithamnion, while in the other the fruit is more complicated, having a sjiecial covering, and with the spores arranged not in indefinite masses, but around a central placenta.

Callithamnion Dasyoides J. Ag. {Gall, ptilophora Eaton mscr.). California.

Callithamnion arbdscula, var. Paeijiciim., Harv., Jour. Proc. Linn. Soc, Vol. VI., No. 24 = G. Pikeanum, Harv., Ner. Am. Bor. 11, p. 230.

OF ARTS AND SCIENCES. 245

Callithamnion heteromorphum J. Ag. Califonia. Chantransia efflorescens, Thuret. {Gallithamnion Ag.). On Rhodymenia. Gay Head, Mass.

DESCRIPTION OF A NEW ALGA OF CALIFORNIA. By Prof. Daniel C. Eaton, of Yale College.

NiTOPHYLLUM SPECTABiLE, fronde subsessili, erecta, maxima, eco- stata atque ut videtur avenia, oblonga, profunde pinnati-lobata ; parte media duple vel triple latitudiue loborum, ssepe in lobum terminalem magnam producta ; lobis laciniisve crebris, patulis, liguliformibus sa-pius integris, nunc apice lobatis vel profundius partitis, margiue vix undulata, rarissime phylla minima obovata e margine vel e disco emittentibus ; soris et coccidiis per totam froudem creberrime con- spersis.

Hab. ad Sanctam Crucem, California: legit Anderson, Aug.- Sept. 1874.

Among the largest species of the genus, often two feet long, or even longer, and, in the spread of the lobes, two-thirds as broad. The lobes are so crowded as to overlap each other, and are 6-8 inches long and about an inch wide, lanceolate or strap-shaped, rather obtuse, mostly entire, but now and then two to three forked, or slighily dichotomously lobed. One specimen bears numerous minute obovate prolifications along the margin, and sparingly on the disk, especially where there has been some injury. No veins visible. The tetraspores are in oblong or irregular sori, thickly scattered all over the frond ; and in the fruiting, plant mature and young coccidia are sprinkled with almost equal pro- fusion. The substance is rather firm, but thin, and not adhering very well to paper, except in the younger portions. I find but two layers of cells in the sterile portions of the lamina. The color is a dull pur- plish-red, more rosy in the newer portions.

246 PROCEEDINGS OP THE AMERICAN ACADEMY

XXI.

DESCRIPTIONS OF NEW SPECIES OF PLANTS, WITH RE- VISIONS OF CERTAIN GENERA.

By Sereno Watson.

Presented May 25, 1877.

Theltpodium Cooperi. Annual, erect or ascending, glabrous and glaucous, a foot high or more, rather lax and slender, sparingly branched : leaves oblong-lanceolate, an inch or two long, sessile, and cordate or auricled at base, acutish, entire : flowers on very short spreading or soon reflexed pedicels; sepals narrow, 1^- or 2 lines long, the narrow purplish petals a half longer: stamens included; anthers short: pods reflexed, 1 to 1^ inches long, subterete, beaked, on pedicels a line or two long. — Collected by Dr. J. G. Cooper near Fort Mohave in 1861, and referred to in Bot. Calif, i. 38; more com- plete specimens, gathered by Dr. Edward Palmer last season on the Mohave River, have been distributed under the above name.

LYCHNIS, Linn. The American species of this genus (conven- iently retained as distinguished from Silene by the increased number of styles and carpels, though otherwise not to be separated from it) are more numerous than has been supposed. So far as known they may be arranged as follows: —

* Calyx clavate-oblong : capsule incompletely septate, 5-toothed.

1. L. ALPiNA, Linn. Biennial or perennial, glabrous, slender, 2 to 10 inches high : leaves linear-oblanceolate : bracts somewhat mem- branous : flowers small, in capitate cymes : petals exserted, 4 or 5 lines long, 2-lobed : capsule shortly stipitate. — Greenland to Labra- dor. (Eui-ope, Asia.)

* * Calyx more or less inflated : capsule not septate, 5-10-toothed : peren- nials.

-(- Dwarf and cespitose, alpine or arctic : stems 1-flowered : seeds with a loose membranous margin : capsule very shortly stipitate.

OF ARTS AND SCIENCES. 247

++ Petals includeil, or nearly so.

2. L. APETALA, Linn. Glandular-pubescent above with short spreading hairs, sparingly so below, 3 to 8 inches high : leaves nar- rowly oblanceolate to linear, an inch or two long : flower nodding, or erect in fruit : calyx much inflated, 6 to 8 lines long, with short acut- ish teeth, strongly purple-veined : petals purple, the blade not broader than the claw, 2-lobed nearly to the middle ; appendages very small ; claw slightly auricled (not 1^ lines wide), naked, — Aleutian Islands and about Behring Straits ; Greenland. (Europe, Asia.)

Var. GLABRA, Kegel. Wholly glabrous. — Rocky Mountains of British America, by Bourgeau ; St. Paul's Island, H. W. Elliott. '

3. L. MONTANA. Glandular-pubescent above with short spread- ing hairs, nearly glabrous below, slender, 2 to 4 inches high : leaves linear-oblanceolate, an inch or two long, the petioles somewhat ciliate; flowers erect: calyx ovate-campanulate, 5 or 6 lines long, with short acute teeth : petals with the emarginate blade not broader than the very narrow claw (not ^ line broad) ; appendages very small : seeds rather broadly margined. — L. opetala, Gray in Am. Journ. Sci. 2 ser. xxxiii. 405, and Proc. Acad. Philad. 1863, 58, in part ; Watson, King's Rep. 36. Mountain peaks of Colorado (n. 132 Parry, 63 Hall & Harbour), and in the Uintas (n. 152 Watson).

++ ++ Petals exserted.

4. L. AFFiNis, Vahl. Glandular-pubescent throughout, 3 or 4 inches high: leaves linear, an inch long or less, ciliate at base: flowers erect: calyx ovate-campanulate, 4 lines long, with short acutish teeth: petals 6 lines long, the blade undulate, emarginate, narrowing from near the top (1|^ lines wide) to the base of the naked claw; append- ages small, toothed. — Greenland to Labrador. (Europe, Asia.)

5. L. KixGii. Resembling the last, covered throughout with a short spreading jiubescence : leaves linear-oblanceolate, 1 to 1^ inches long : calyx 6 lines long : petals with the short flat blade rather deeply emarginate ; appendages entire or toothed ; claw ciliate, rather broadly auricled : filaments ciliate. — L. Ajanensis ?, Watson, King's Rep. 37, but quite distinct from that Asiatic species. Peaks of the Uintas at head of Bear River ; apparently also in Northwestern Wyoming (n. 43 Parry), but with a shorter calyx and petals, and naked filaments.

H- -(- Flowers rarely solitary : seeds tuberculate. ++ Low, arctic or alpine.

6. L. TRiFLORA, R. Brown. Rather stout, glandular-pubescent throughout, 2 to 9 inches high : leaves thickish, narrowly oblanceolate,

248 PROCEEDINGS OF THE AMERICAN ACADEMY

an inch long : flowers usually 2 or 3 together, nearly sessile, erect : calyx much inflated, densely pubescent, 5 or 6 lines long, with short rounded teeth, 2>ui*plish and strongly veined : petals light rose-color, 7 or 8 lines long ; blade narrowly obcordate, nearly 2 lines broad ; appendages rather prominent, entire ; claw narrowly auricled. — Green- land, from Polaris Bay (Dr. Bessel) southward.

7. L. Californica. Slender, cespitose, glandular-puberulent above, nearly glabrous below, 2 to 4 inches high, deep green : leaves linear to linear-oblanceolate, an inch or two long, ciliate at base : flowers 1 to 3, on slender pedicels : calyx ovate-campanulate, 4 or 5 lines long, deeply toothed, the teeth ovate-triangular, acutish : petals about 7 lines long, the obovate blade bifid, lobed on each side near the base ; ap- pendages prominent, entire or toothed ; claw broadly auricled, the auricles prolonged upward : capsule shortly stipitate : styles sometimes only 3 or 4. — In the high Sierra Nevada; near Ebbett's Pass (n. 2081 Brewer), on Mount Dana (H. N. Bolander), and in Sierra or Plumas County, J. G. Lemmon.

++ ++ Taller, not alpine nor arctic. = Petals included or nearly so.

8. L. Drummondii, Watson. Stems strict and rather stout, a foot or two high, finely glandular-pubescent above : leaves narrowly oblanceolate, 2 or 3 inches long, erect: flowers few, erect, on stout often elongated strictly erect pedicels : calyx cylindric, becoming oblong-ovate, 5 or 6 lines long, with short acutish teeth : petals rarely slightly exserted, white or purple, the entire or emarginate blade nar- rower than the auricled (a line wide) claw ; appendages minute : cap- sule nearly sessile. — King's Rep. 37 ; Silene Drummondii, Hook. Fl. i. 89 ; L. apetala. Gray, 1. c, in part. Winnipeg Valley and on the Saskatchewan, and in the mountains to New Mexico and S. Utah.

= = Petals long-exserted.

9. L. NUDA, Watson, 1. c. Slender, finely pubescent, a foot high : leaves narrowly oblanceolate, 2 or 3 inches long : flowers on slender pedicels, nodding, at length erect : calyx 4 to nearly 6 lines long, cylindric becoming ovate-oblong, with rather narrow acutish teeth : petals white or rose-colored, 8 lines long, the broad limb 2-parted with the segments deeply bifid, the lobes irregular and mostly acute ; appendages ovate, entire, thickish ; claw broadly auricled, margined to the base : capsule nearly sessile. — East Humboldt Mountains, Nevada.

10. L. Parryi. Slender, finely pubescent, glandular above, a foot high or less : leaves linear, an inch long or more : flowers erect

OF ARTS AND SCIENCES. 249

or somewhat nodding, the lateral pedicels mostly short : calyx inflated, ovate-oblong, 6 lines long, with broad acutish teeth : petals purplish, 8 lines long, the broad blade cleft to the middle (the rounded segments entire, crenate, or bifid) and with a short narrow lobe on each side ; appendages quadrate or ovate, thin and crenate ; claw broadly auricled, very narrowly attenuated below : stipe of capsule a line long or more. — Northw^estern Wyoming, collected by Dr. C. C. Parry on the expedition of Capt. W. A. Jones to the Yellowstone in 1873.

11. L. ELATA. Tall and slender, finely pubescent, slightly glan- dular above, 1^ feet high or more: leaves narrowly oblanceolate, 2 to 4 inches long, acute or acuminate : flowers nodding or erect, on slender pedicels : calyx inflated, ovate-oblong, 6 or 7 lines long, with triangular acutish teeth: petals purplish, 9 to 12 lines long, the blade cleft to the middle, with a narrow shorter lobe on each side ; appendages broad, toothed ; claw not auricled, attenuate to a t'ery narrow base : stipe of capsule nearly 2 lines long. — Collected in the Rocky Mountains of British America by Bourgeau in 1858, and distributed as Silene Sconleri.

Lavatera insularis. a stout perennial, probably woody at base, finely stellate-pubescent : leaves with a narrow sinus, 3 to 6 inches broad, 7-lobed to the middle ; the lobes rounded and obtuse, coarsely crenate : flowers solitary in the axils, on stout deflexed and curved pedicels nearly an inch long and with one or two small bractlets or naked : involucre of three nearly distinct oblong-spatulate acutish bracts, 6 lines long : calyx 5-cIeft to the middle with broadly ovate acute lobes, becoming an inch long in fruit : petals spatulate and un- guiculate, emarginate, naked at base, apparently purplish yellow with the claw dai-ker, 1^ inches long: styles not exserted : fruit half an inch broad, slightly pubescent, about 10-carpelled, the sides of the carpels smooth. — Received from D. Cleveland, Esq., of San Diego, and collected on the Coronados Islands, 20 miles distant from that town. Like the following, it differs from the two previously known California species in the nearly distinct bracts of the involucre.

Lavatera venosa. Similar in habit to the last, glabrous or nearly so : leaves 3 to 4 inches broad, 7-cleft to the middle with tri- ammlar acutish lobes: flowers two or three in the axils, on slender' ascending naked pedicels 1 to H inches long: involucre of 3 nearly distinct oblong-ovate acutish bracts, equalling the calyx, 3 or 4 (be- coming 7) lines long: petals 15 lines long, cuneate-obcordate, deep purple with darker veins, villous on each side at base: styles long- exserted: fruit 5 lines broad, glabrous, about 10-carpelled: sides of the

250 PROCEEDINGS OF THE AMERICAN ACADEMY

carpels strongly veined. — From San Benito Island, off the coast of Lower California ; collected by Dr. T. H. Streets, U. S. N., December, 1875. This is the fourth species of the genus that has been found on the small islands near the southern coast of California, and is peculiar in the prominent veins upon the sides of the carpels.

Malvastrum Palmeri. A stout perennial, densely stellate- pubescent and -hirsute : leaves broadly ovate, 2 or 3 inches long, some- what 3-o-lobed, the lobes obtusish, crenately toothed ; stipules conspic- uous, broadly lanceolate, acuminate, nearly half an inch long: floral bracts large and conspicuous : flowers nearly sessile, in terminal clus- ters, large (1^ inches broad), yellowish rose-color: bractlets linear- lanceolate, 8 to 10 lines long, nearly equalling the acuminate calyx- lobes : carpels rounded, somewhat pubescent. — At Cambra in South- ern California, a mile from the sea-beach ; collected by Dr. E. Palmer (n. 50 of his distribution), July, 1876. Marked by its stout leafy habit and by its large floral bracts and calyx.

LuPiNUS TRIFIDUS, Torrey in hei'b. Very closely resembling L. micranthus, but the lower lip deeply 3-cleft with linear segments : pod narrower and shorter (about 6 lines long and \\ broad), usually 5-6- seeded : seeds a line broad, uniformly mottled : flowers 3 lines long or less, mostly in a single terminal whorl. — L. micranthus, var. trijidus, Watson, Rev. Lup. 535. Near Sau Francisco, by various collectors, and recently in fine specimens by Mr. G. R. Vasey. The ordinary L. micrant/ms, besides the nearly entire lip. has a pod often an inch long and 2k lines broad, 6-9-seeded, and the larger seeds variously mottled, but with a lighter spot around the sometimes dark eye.

LuPiNUS Arizonicus. Annual, slender, erect, a foot high or less, villous throughout with scattered spreading hairs : leaflets 6 to 8, shorter than the slender petioles, linear-oblanceolate, obtuse or acute, a half to an inch long: flowers scattered in loose racemes; bracts long and some- what persistent: calyx rather broad at base, the lower lip trifid: petals 4 or 5 lines long, deep purplish blue or sometimes ochroleucous, the broad wings (2| lines wide) exceeding the orbicular standard : pod 6 to 9 lines long, 3-6-seeded : seeds rounded, compressed, with prominent sides and rather thin margin, 1 ^ lines broad, nearly white. — L. concin- mis, var. (?) Arizonicus, Watson, Rev. Lup. 537. In Arizona and South-eastern California. The typical L. concinnus, Agh., is much more densely villous, lower and of more diffuse habit ; leaflets broader ; calyx narrow at base, and flowers narrower (wings \\ lines broad, and standard elliptical), the petals usually becoming reddish purple, or the standard yellowish : pods 3-4-seeded, but seeds similar.

OF ARTS AND SCIENCES. 251

PsORALEA Califouxica. Stems very short and clustered, from tul)eroiis (?) roots : pubescence short, silky, appressed : leaves digi- tately 5-foliolate, the leaflets broadly oblanceolate, acutish, 9 to 15 lines long ; stipules lanceolate, scarious and deciduous : peduncles shorter than the petioles : flowers on slender pedicels, in a short raceme : calyx silky-villous, half an inch long, the linear acuminate lobes a little ex- ceeding the persistent petals : pod very thin, somewhat villous, beaked : seeds smooth, compressed and rather thin, 2 to 2.V lines long. — At McGinuis' Ranch, near head of Salinas River, 25 miles from San Luis Obispo, California; collected by Dr. Edward Palmer, July, 1876, in mature fruit. Resembling in habit P. esculenta of the eastern plains.

Lythrum breviflorum. Much branched, with the habit of nar- row-leaved forms of L. alatum, the long slender branches flower- bearing their whole length : calyx strongly striate, nearly 2 lines long in fruit, exceeding the narrow bracts, shortly pedicellate : petals 6, pur- ple, a line long or more : stamens 6 or 8 : seeds minute, round-ovate, somewhat compressed. — L. alatum, var. (?) hrevijiorum. Gray in PI. Lindh. 187 (n. 609 Lindheimer, 1847, in part). On damp rocks in the Guadalupe River, Texas. The seeds of L. alatum are linear- oblong and twice longer.

Q^xoTHERA (Taraxia) Palmeri. A dwarf cespitose annual ; branches very short, stout, covered with a loose white epidermis : leaves lanceolate or oblanceolate, an inch or two long, pubescent, ciliate, entire or nearly so : calyx-tube filiform, nearly equalling the leaves : petals yellow, 2 lines long : capsules crowded, ovate, 3 or 4 lines long, quadrangular at base, acute and strongly winged above, dehiscing along the truncate upper edge of the wings : seeds lanceolate- ovoid, terete, | line long, nearly smooth. — Collected in Arizona by Dr. Edward Palmer, 1876.

Qj^NOTHERA TRILOBA, var. (?) PARViFLORA. Flowers Very small, not more tlian an inch or two long, fertilized in the bud, and rarely fully opening : fruit abundant, forming at length a densely crowded hemispherical or cylindrical mass, nearly 2 inches in diameter and often 2 or 3 inches high. — A curious form of this very va'riable species, or possibly distinct, frequent in butfalo-wallows in the neighbourhood of Ellis, Kansas, where it has been collected by Dr. Louis Watson. It is also found in previous collections, and is probably common on the plains of Kansas and Nebraska in like localities. Under cultivation in the Botanic Garden, Cambridge, it has retained its peculiarities as respects the manner of flowering. It is strictly an annual, coming early into bloom. The capsules are rarely over a half inch long,

252 PROCEEDINGS OF THE AMERICAN ACADEMY

less attenuate above and smaller than is usual in the ordinary large- flowered state of the plant.

Mentzelia hirsutissima. Stout, erect, with ascending branches, very hirsute with spreading rigid hairs in addition to the usual barbed pubescence: leaves linear-lanceolate, 1^ to 3 inches long, acuminate, irregularly pinnatifid with divaricate acute segments and teeth ; lobes of the floral leaves vei'y narrow : flowers terminal, sessile : calyx-limb deeply 5-cleft, 8 to 12 lines long, the lanceolate lobes long-acuminate : petals yellow, acute, 1^ inches long: filaments very numerous, orange- colored above, shortly cuspidate on each side of the anther, nearly ^ inch long, shorter than the style: capsule oblong, ^ inch long. — Angels Island, in the Gulf of California ; Dr. T. H. Streets, U. S. N,, February, 1876. With M. tricuspis forming a section distinct from § Bartonia, characterized by the filaments dilated and bicuspidate above ; style tubular and terete, 3-cleft at the summit (sometimes twisted) ; seeds (in M. tricuspis) in one row on each thin jjlacenta, horizontal, not mar- gined, irregularly flattened, coarsely and irregularly rugose, opaque and very minutely and densely tuberculate.

Elaterium minimum. Stems very slender, almost filiform, a foot or two long, glabrous or nearly so : leaves thin, smooth above, white-papillose and scabrous beneath, triangular-cordate and more or less deeply hastate-lobed, 1 to li- inches broad, the lobes entire or some- what serrate: the sterile raceme little exceeding the leaves; limb of the flowers 4 lines broad : fertile flowers on slender pedicels 1 to 6 lines long, the limb 3 lines broad, and the slender tube 2 lines long : fruit very small (4 lines long), acute at each end and beaked above by the persistent calyx-tube, echinate with spine-like processes, 2-celled and bursting irregularly on each side near the top; cells 3-ovuled, mostly 1-seeded: seeds oblong-ovate, 1^ lines long, compressed, dark-colored. — Marah minima^ Kellogg, Proc. Calif. Acad. ii. 18. On Cerros Island, off Lower California (Dr. J. A. Veatch, Dr. T. H. Streets), and at Cape St. Lucas, L. J. Xantus.

Elaterium Bigelovii. Very similar : leaves more decidedly has- tate, the middle segment lanceolate, acute and cuspidate, the lateral ones 2-lobed, all entire or obscurely sinuate : staminate panicles shorter than the leaves: flowers smaller; limb less than 2 lines broad: ovary smooth, seemingly 1-ovuled: fruit unknown. — In the Lower Colorado Valley, Dr. J. M. Bigelow and Dr. E. Palmer. Referred to Melolhria pendula in the Botany of California.

Angelica leporina. Tall and stout in the manner of the genus, glabrous : leaves bipinuate ; leaflets linear-lanceolate, acuminate, entire

OF ARTS AND SCIENCES. 253

or coarsely few-toothed, 1 to 3 inches long : umbels naked, the rays very unequal and somewhat scabrous: fruit small (about 1^ lines long) ; dorsal ribs prominent ; oil-tubes solitary or the lateral in pairs. — Rabbit Valley, S. Utah ; collected by L. F. Ward on Col. J. W. Powell's Exploring Expedition. Distinguished from our only other narrow-leaved species (A. lineariloha, Gray) by the very much shorter fruit.

MiRABiLis Greenei. Very stout, with the habit of M. multijlora, somewhat glandular-puberulent : leaves rather thick, ovate, acute, attenuate to a short stout petiole, 3 inches long: involucre 7— 10-flow- ered, acutely lobed, 1 to 1^ inches long : perianth tubular-funnel form, a half longer than the involucre, greenish purple : fruit ovate-oblong, usually abruptly contracted near the base, rather strongly 5-angled, the sides somewhat ridged longitudinally and more or less tuberculate, 3 lines long or more. — On mountain sides about Yreka, California; in flower and fruit, June, 1876; Rev. E. L. Greene. The fruit ap- proaches that of an Oxyhaphus.

Abronia micrantha, Torrey, Frem. Rep. 96, and Marcy's Rep. t. 18 (as A. cycloptera). Prostrate : peduncles shorter than the petioles : flowers small and inconspicuous, 3 or 4 lines long, reddish green, the limb scarcely 2 lines broad : fruit orbicular with three thin wings, emarginate above and below, 8 to 10 lines wide, the body rather broad and with a light spongy exterior. — Frequent on the plains from the Saskatchewan to the Arkansas and S. W. Colorado, and well repre- sented in the figure of Marcy's Report, excepting the limb of the perianth. A. cycloptera, Gray (Am. Journ. Sci. 2 ser. xv. 319, excl. syn.), with which it has been confounded, is a more southern species of Western Texas, New Mexico, and S. Colorado, of stouter habit, and with large showy flowers upon elongated peduncles. The fruit has a firmer and more prominently veined wing, emarginate at neither end, the firm smooth narrow body 7 to 12 lines long and usually 3-nerved between the wings. The third species of the section, A. Crux-Maltce, Kellogg (Proc. Calif. Acad. ii. 71, fig. 16), of Western Nevada, with very showy flowers upon peduncles about equalling the leaves, has a smaller orbicular-winged fruit (5 or 6 lines in diameter), the ovate body pubescent and coarsely reticulate-pitted.

RuMEX occiDENTALis. Tall and rather slender, often 3 to 6 feet high : leaves oblong-lanceolate, the lowest sometimes ovate, usually narrowing gradually upward from the truncate somewhat cordate base, not decurrent on the slender often elongated petiole, acute, a foot long or more, scarcely uudulate : panicle narrow, elongated, nearly leafless :

254 PROCEEDINGS OF THE AMERICAN ACADEMY

pedicels filiform, 3 to 6 lines long, obscurely jointed near the base : valves without grains, broadly cordate with a very shallow sinus, becoming about 3 lines in diameter, often denticulate near the base : akene a line and a half long. — From Alaska to Northern California, eastward to the Saskatchewan and Labrador, and southward in the mountains to Colorado and New Mexico. It has hitherto been referred to R. longifolius, DC, but that Old World species has narrow and very undulate leaves, broadest near the middle, the pedicels with a tumid joint below the middle, and the valves more deeply cordate.

ERIOGONUM, Michx. During the seven years that have elapsed since the thorough revision of the Eriogonece by Dr. Gray, published in the eighth volume of these Proceedings, so much additional mate- rial has been collected and so many new species have been described that it seems not useless to give again a summary of the two larger genera of the group. Some modifications are made in the arrange- ment of the species in Eriogonum, based mainly upon the characters of the bracts and involucres, by which the genus is divided naturally into three princijjal sections, as follows : —

§ 1. Involucres not nerved or angled, 4-8-toothed or -lobed, more or less broadly turbinate (mostly 2 lines long or more) : bracts foliaceous, indefinite in number (2 to 5 or more), rarely somewhat ternate. Mostly perennial. — Ederiogonum.

* Tall perennials with scarcely branching caudex, more or less villous-pubescent or silky, with long oblanceolate alternate leaves and alternate branches, loosely di- or trichotomous above : bracts small : involucres pedunculate, soli- tary, with 5 erect teeth : akenes large (2 to 4 lines long): embryo straight and axile.

H- Akenes membranously winged : flowers not attenuate at base, nor much en- larged in fruit. — (§ Alata, Benth., excl. sp.)

1. E. ALATUM, Torr. Loosely silky-villous throughout, or the leaves nearly glabrous except on the margin and midrib : flowers a line long, yellow, nearly glabrous, abrupt at base : akene winged the whole length, 3 lines long. — Nebraska to W. Texas and Arizona.

2. E. TRISTE, Watson, Proc. Am. Acad. x. 347. Similar, but nearly glabrous : flowers deep purple, glabrous, somewhat narrowed at base: akene 4 lines long. — S. Utah.

3. E. HiERACiFOLiUM, Benth. Hoary-pubescent throughout and leaves usually tomentose beneath : flowers pubescent, yellow or rose- colored, 1^ lines long (or 2 lines in fruit), abruptly narrowed at base : akenes 2^ lines long, winged above the middle. — W. Texas and Rio Grande Valley.

OF ARTS AND SCIENCES. 255

•^ -t- Akenes not winged : flowers attenuate at base, enlarging in fruit. — (sp. of § Eriantha, Bentli., Torr. & Gray.)

4. E. LONGiFOLiUM, Nutt. Hoary-pubescent throughout and the leaves tomentose beneath : involucres and flowers densely white-silky : Hewers mostly herbaceous, 1 h becoming 2 or 3 lines long : akene 2 lines long, pubescent above. — Indian Territory and Texas ; Florida.

* * Tomentose perennials, with radical leaves, and naked scapelike stem, di- or

trichotomous above, with large conspicuous bracts : involucres solitary, ses- sile, with 6 erect teeth : flowers attenuate to a stipelike base, pubescent, en- larging in fruit : akene mostly smaller : embryo straight and axile, or nearly so. — (§ Eriantha, Benth., Torr. & Gray, excl. sp.)

5. E. TOMENTOSUM, Michx. Tall, herbaceous, rufous-tomentose : radical leaves elongated, oblanceolate-spatulate ; bracts elliptical, ses- sile, smooth above undulate: flowers white, tomentose, 2 lines becoming 4 or 5 lines long, the inner sepals largest: akene 2| lines long. — S. Carolina to Florida.

6. E. UNDULATUM, Benth. A little-known Mexican species, described as low and cespitose, woody, much branched and leafy : leaves and bracts ovate, petioled, with revolute undulate margins : flowers much smaller.

7. E. Jamesii, Benth. Eather slender, herbaceous, with branch- ing eaudex, a foot high or less, wdiite-tomentose : leaves and bracts oblong-oblanceolate, the latter shortly petiolate : flowers whitish, silky, 2 becoming 3 or more lines long : akene 2 lines long. — Var. FLAVESCENS. Stouter ; flowers yellow or yellowish. £. Jlavi(m,va.r. veyetius, Torr. & Gray. Rev. 156. — Colorado to New Mexico and W. Arizona. The variety is distinguished from the next by the strictly solitary sessile involucres.

* * * Perennials, more or less tomentose or rarely glabrous, with peduncles

naked and scapelike or verticillate-bracteate in the middle : bracts mostly conspicuous : involucres 5-8-toothed or -cleft, in a simple or compound um- bel (rarely sub-capitate) or solitary : flowers mostly attenuate to a stipelike base: akenes glabrous or nearly so (2 lines long or less) : embryo mostly somewhat curved and excentric (as in the rest of the genus). — (§ Umbellata, Benth., in part. §§ Umbellata & Pseudo-Umbellata, Torr. & Gray.)

■I- Teeth of involucre short, erect or nearly so. t-f Umbel simple (compound in n. 13), on a naked peduncle. = Flowers villous.

8. E. FLAVUM, Nutt. Tomentose throughout, a span high or less ; eaudex branching : leaves oblanceolate : umbel of 3 to 9 rays, often short : flowers yellow, 2 or 3 lines long, long-attenuate at base, very

256 PROCEEDINGS OF THE AMERICAN ACADEMY

silky. — Washington Territory to the Saskatchewan and south to Colorado.

9. E. ANDROSACEUM, Bcnth. Dwarf, tomentose throughout or smoother above ; caudex branching : leaves oblanceolate : rays short, slender: flowers yellow, 2- or 3 lines long, short-attenuate, sparingly villous. — Rocky Mountains of British America.

10. E. PYROL^FOLiUM, Hook. Dwarf, somewhat villous ; caudex sim^jle : leaves ruund-obovate to oblong, thick : rays few, very short : flowers rose-color, 2 lines long, short-attenuate, sparingly villous. — Var. CORYPH^UM, Torr. & Gray. More tomentose, with narrower leaves and smaller flowers. — Mountains, N. California and Oregon.

= = Flowers glabrous : caudex diffusely branched. — In the Sierra Nevada.

11. E. INCANUM, ToiT. & Gray. Somewhat cespitose , tomentose, low : leaves oblanceolate, shortly petioled : bracts and involucres small : flowers yellow, often reddish.

12. E. MARiFOLiuM, Torr. & Gray. Low and very slender, dif- fusely branched below, tomentose : leaves ovate to oblong : bracts and involucres (a line long) small : flowers yellow or yellowish.

13. E. URSiNUM, Watson, Proc. Am. Acad. x. 347. Taller and stouter, tomentose, villous above: leaves ovate: bracts elongated: umbel compound : involucres large : flowers whitish.

•M- ++ Involucres solitary : peduncle verticillate-bracted in the middle : dwarf.

14. E. Kelloggii, Gray, Proc. Am. Acad. viii. 293. Very slender, much branched at base, villous-tomentose : leaves oblanceolate, 2 to 4 lines long: flowers glabrous, white or rose-colored, Ij to 2^ lines long. — Mendocino Co., California.

15. E. THYMOiDES, Benth. Densely branching and woody, with revolute linear leaves 1 to 5 lines long : peduncles slender : flowers densely villous with long hairs, purplish, 2 or 3 lines long, with broad sepals. — Oregon and Washington Territory.

H- ^- Involucres deeply lobed ; lobes becoming reflexed.

++ Flowers pubescent : involucres solitary (rarely umbellate in n. 18), on verti- cillate-bracted peduncles (naked in n. 16) : low, cespitose, with yellow flow- ers, and leaves tomentose both sides.

16. E. c^SPiTOSUM, Nutt. Dwarf, densely matted : leaves ovate- to oblong-spatulate, 2 to 6 lines long : peduncles naked. — N. W. Nevada to Wyoming Territory.

17. E. DouGLASii, Benth. Larger and more diffuse: peduncles with a whorl of oblanceolate leaves in the middle. — N. California, Oregon.

OF ARTS AND SCIENCES. 257

18. E. SPH^ROCEPHALUM, Dougl. Similar, but still more diffuse : leaves linear-spatulate, often revolute : the whorl of bracts on the peduncle sometimes subtending a 2-4-rayed umbel, the lateral rays also bracteate. — N. California and Nevada, to Washington Territory.

++ -w Flowers glabrous: umbels simple or compound, on naked (rarely l-braeted) peduncles (verticillate-bracted in n. 22): caudex diffusely branched: leaves glabrate above or glabrous, oblanceolate or spatulate.

19. E. UMBELLATCM, Torrev. Tomentose: umbel simple, of 3 to 10 naked rays. — Var. monocephalum, Torr. & Gray. A reduced dwarf alpine form, the naked or bracteate peduncle bearing a solitary involucre: leaves small. — N. California and Oregon to Colorado; common.

20. E. Torre yanum, Gray. Glabrous throughout : umbel of few rays, the lateral rays bracteate in the middle and often divided : flow- ers large. — In the Sierra Nevada.

21. E. stellatdm, Benth. Tomentose: rays 2 to 4, usually and often repeatedly cymosely divided : the nodes and lateral rays all leafy-bracted. — £. elUpticum, Nutt. E. 2)oJyantkum, Benth., Torr. & Gray. — Var. bahi^forme. Umbel very compound: leaves mostly small, often densely tomentose both sides. — Oregon to S. California and Arizona.

22. E. HERACLEOiDES, Nutt. Similar, but the peduncle usually verticillate-bracted : leaves narrower, mostly somewhat revolute or undulate: umbel about 6- (1-11-) rayed, usually some or all of the rays once or twice divided. — Washington Territory to Utah.

++++++ Flowers glabrous : umbels usually compound, on naked peduncles : caudex short and thick : leaves round to oblong, tomentose.

23. E. COMPOSITUM, Dougl. Leaves oblong-ovate, cordate : pedun- cle stout and tall : umbel compound, of 6 to 10 elongated rays. — Washington Territory and Idaho to N. California.

24. E. LoBBii, Torr. & Gray. Leaves oval or rounded : peduncles short, decumbent : rays few, usually very short and undivided : flowers less attenuate at base. — In the Sierra Nevada.

* * * * Perennials, densely tomentose, with naked peduncles : bracts small : involucres with 5 short erect teeth : flowers small, abruptly narrowed at base, pubescent: akenes densely villous. — (Lachnogyna, Torr. & Gray.)

25. E. ACAULE, Nutt. Very dwarf and densely matted : leaves crowded, 2 or 3 lines long, oblong: peduncle half an inch Iiigh, bear- ing a head of 1 to 5 nearly sessile involucres. — S. Idaho to S. W. Col- orado.

VOL. XII. (n. S. IV.) 17

258 PROCEEDINGS OF THE AMERICAN ACADEMY

26. E. LACHNOGTNUM, Torr. Cespitose : leaves oblong-lanceolate : the slender peduncle a foot high, sparingly dichotomous above : invol- ucres solitary, sessile or long-pedunculate : flowers densely tomentose : akene attenuate above, 2 lines long. — S. Colorado and New Mexico.

***** Perennial, villous, dwarf, with naked peduncles bearing a subcapi- tate umbel : bracts conspicuous : involucres campanulate, 4-8-parted, with erect somewhat unequal lobes : flowers abruptly attenuate at base, villous : akenes glabrous.

27. E. viLLiFLORUM, Gray, Proc. Am. Acad. viii. 630. Densely cespitose, very villous throughout, the crowded oblanceolate leaves half an inch long : peduncles slender, an inch high : bracts linear : invol- ucres few in the loose heads, bracteate at base, the slender pedicels a line long: flowers 1^ lines long, but little exserted; sepals oblong and nearly equal, silky within and without. — S. Utah; a very peculiar species.

****** Annuals, di- or trichotomously divided, with mostly conspicuous leafy bracts: involucres turbinate, unequally 4-8Iobed or parted (lobes erect), long-pedunculate or sometimes sessile in the forks: flowers not atten- uate at base: akenes glabrous. — {§ Foliosa, Benth., Torr. & Gray.)

f- Involucres rather large, deeply cleft : flowers glabrous ; sepals broad and cordate at base.

28. E. Abertianum, Torr. Stout and leafy, often tall, silky-vil- lous : leaves ovate or subcordate, the bracts becoming oblanceolate or linear: flowers rose-colored, the outer sepals round-cordate, at length 2 lines broad, the inner linear-oblong. — E. Arizona and New Mexico.

29. E. pharnaceoides, Torr. Tall and slender, loosely branched tomentose and villous : leaves linear-oblanceolate, revolute : flowers whitish, a line long ; outer sepals ovate, at length bigibbous at base, the inner linear-oblong, retuse. — Arizona and New Mexico.

-1- -(- Involucres divided : flowers pubescent, yellow ; sepals narrow, closely appressed to the akene.

30. E. SALSUGiNOSUM, Hook. Low and leafy, glabrous, somewhat fleshy : leaves spatulate-oblanceolate, the bracts becoming linear : akene acutely triangular, a line long. — W. Wyoming to S. Utah and S. W. Colorado.

-I- 4- H- Involucres very small, 4-cleft or -parted, few-flowered : flowers pubes- cent, minute, narrow at base : difl^usel}' branched and very slender, glandular : bracts mostly very small.

31. E. SPERGULiNUM, Gray. Leaves and bracts linear-oblanceolate, hirsute : involucres 1-2-flowered : flowers nearly a line long, slightly puberulent. — In the Sierra Nevada.

OF ARTS AND SCIENCES. 259

32. E. HiRTiFLORUM, Gray in herb. Somewhat glandular-puberu- lent, 6 inches high or less : bracts oblong, hispid : involucres half a line long or less, on erect or nodding pedicels 1 to 3 lines long, or sessile in the forks, 3-o-flowered : flowers very hirsute, reddish, half a line long or less : akenes slightly exserted. — Collected by Dr. Gray, 1872, probably in the mountains of California.

§ 2. Involucres campanulate or short-turbinate, not angled or nerved, with 5 rounded erect teeth, pedunculate in diffuse repeatedly di- or trichotomous pan- icles : bracts not foliaceous, all ternate, small and mostly triangular and rigid: flowers not attenuate at base: ovary glabrous. Mostly annuals. — Ganysma.

* Annuals : leaves all radical or nearly so, and mostly rounded : involucres, flowers and akenes small (a line long or less). — (§ Pedunculata, Bentii., Torr. & Gray, e.xcl. sp.)

■t- Flowers glabrous ; outer sepals broad and somewhat cordate at base, the inner much smaller : pedicels very short, deflexed : leaves floccose-tomen- tose.

33. E. BRACHYPODUM, Torr. & Gray. Low, depressed, rather rigid, much branched and glandular: iuvolucres campanulate-turbinate, ^ to f line long, on pedicels less than a line long. — S. E. California.

34. E. Parryi, Gray in Proc. Am. Acad. x. 77. Less rigidly branched : iuvolucres rather narrowly turbinate, a line long : pedicels slender, 1 to 3 lines long. — S. Utah.

35. E. DEFLEXUM, Torr. Taller and more erect, glabrous above the base : involucres and pedicels as in £J. brachypodum, but more secund along the branches ; jjedicels reflexed, rarely a line long or more : outer sepals becoming a line long, the inner very small, obovate and retuse. — Nevada and Utah to S. K. California.

H- t- Flowers glabrous ; outer sepals panduriform or oblong and emarginate or retuse, the inner narrower : pedicels longer : leaves floccose-tomentose. ++ Pedicels deflexed : outer sepals oblong or somewhat broader above.

3G. E. NUTA:ys, Torr. & Gray. Low, sparingly branched : leaves small : pedicels minutely glandular : involucres campanulate : outer sepals nearly obcordate. — N. E. California and N. Nevada.

37, E. Watsoni, Torr. & Gray. Taller, more diffuse, glabrous : leaves larger, obtuse, round, often cordate at base : involucres narrowly turbinate : outer sepals oblong, often retuse. — N. Nevada.

38. E. CERNUUJi, Nutt. Like the last, but leaves broadly ovate, acute : involuci'es turbinate-campanulate : flowers narrower at base, the outer sepals broader above, retuse. — E. Oregon to Colorado and New Mexico.

260 PROCEEDINGS OF THE AMERICAN ACADEMY

++ -M. Pedicels erect or somewhat spreading : outer sepals much broader above.

39. E. Thuebeki, Torr. Very slender, tomentose below: leaves small : pedicels a half to an inch long : involucres often glandular- puberulent : flowers becoming a line long ; outer sepals with a large rounded terminal lobe, minutely pubescent in the centre. — S. Cali- fornia and Arizona.

40. H ROTUNDiFOLiUM, Benth. Rather stouter and more diffuse, with larger leaves : pedicels shorter and more rigid : flowers becoming \l lines long, the outer sepals very broadly dilated above. — New Mexico and W. Texas.

•*--(--(- Flowers mostly minutely glandular-hispid, longer than the small in- volucre, the outer sepals mostly ovate : pedicels long and filiform, rarely deflexed.

++ Leaves floccose-tomentose : stem not inflated : pedicels all in the forks or terminating the branches.

41. E. PUSiLLUM, Torr. & Gray. Often tall and rather stout: leaves rounded or obovate, usually less tomentose above: greenish bracts and involucres minutely glandular-hispid : involucres hemispheri- cal : flowers yellow, often reddish : akene thick-lenticular. — N. W. Nevada to Arizona and S. California.

42. E. RENiFORME, Torr. Low and slender, glabrous : leaves reni- form or cordate-orbicular, densely white-tomentose both sides : bracts smooth, the margins ciliate : involucres smooth, turbinate-campanulate, nearly a line long : flowers rose-colored, glabrous ; sepals ovate-oblong. — S. California.

43. E. SUBRENIFORME. Sparingly villous at the nodes: leaves round-reniform or -cordate, tomentose beneath, silky-villous above : involucres smooth, turbinate-campanulate, ^ line long : flowers rose- colored, glabrous, or slightly hispid ; sepals oblong. — E. rem'forme, Torr. & Gray, Rev. 184, in part. Arizona, S. Utah.

44. E. TuOMASir, Torr. Low, very slender, glabrous : leaves rounded and ovate, small : bracts minute, glabrous : involucres turbi- nate-campanulate, smooth : flowers yellowish, often reddish, slightly hispid or glabrous ; outer sepals often much dilated below, the inner Hnear-oblong. — S. California to S. W. Colorado.

■M- ++ Leaves more or less villous-pubescent or glabrous, not tomentose : stem often inflated : pedicels often scattered and secund on the branches.

45. E. TRiCHOPODUM, Torr. Glabrous, diffusely much branched and very slender, the stem rarely inflated : leaves pubescent : bracts very small: involucres minute: pedicels 3 to 0 lines long : flowers yellow-

OF ARTS AND SCIENCES. 261

ish, pubescent, I line long ; sepals ovate-lanceolate, acute. — S. Cali- fornia to New Mexico.

46. E. iNFLATUM, Torr. Taller, less branched, the stem and inter- nodes longer and often inflated: pedicels 6 to 12 lines long: flowers and akene twice larger. — S. California to Nevada and Arizona.

47. ¥j. Gordoni, Bentli. A similar species, but glabrous through- out, or the petioles slightly pubescent: flowers glabrous, light rose- color : outer sepals ovate, the inner oblong. — Colorado.

48. E. GLANDULOSUM, Nutt. Beset with short-stipitate glands : leaves small, obovate, somewhat villous : involucres glabrous, half a line long, turbinate-campanulate: flowers nearly a line long, slightly hispid ; sepals oblong-ovate, acutish. — Collected only by Dr. Gambel, probably in New Mexico.

49. E. SCALARE. A peculiar allied species, collected in imperfect specimens by Dr. T. H. Streets, U.S.N., at Canvas Point, on the coast of Lower California. Main branches of the inflorescence slender and glabrous, a foot long, with opposite or alternate brauchlets (sometimes in threes), divaricate or ascending : bracts distinct, linear, a line or two long, spreading or reflexed, on the branchlets smaller and erect : pedicels scattered on the brauchlets, 1 or 2 lines long, filiform, ascending : in- volucres narrowly turbinate, f line long, glabrous : bracteoles spatulate, naked : flowers slightly pubescent, a line long ; sepals oblong, the inner a little narrower.

* » Perennial or biennial, the peduncles and inflorescence glabrous and leafless : involucres and flowers larger, glabrous: akene 2 or 3 lines long. — (Spec, of §§ Pedun'cclata & Alata, Bentli., Torr. & Gray.)

•f- Perennial ; woody caudex much branched and leafy : densely white-tomentose.

50. E. TEXELLU3I, Torr. Tall; branches of the caudex short and crowded or elongated : leaves ovate or i-ouuded, tomeutose both sides : inrtorQ^ceuce rather sparingly branched : flowers white or pinkish, be- coming 1| lines long; outer sepals broadly obovate or orbicular, the inner linear-oblong. — S. Colorado to W. Texas and New Mexico.

■i- -4- Biennial (?) ; peduncle very sparingly branched : leaves all radical, villous.

51. E. ciLiATUii, Torr. Leaves broadly spatulate, 2 inches long, glabrous excepting the very villous margin and midrib : involucres few, long-pedunculate : flowers deep red ; sepals ovate, acute, the inner narrower. — Northern Mexico.

52. E. ATRORUBENS, Engelm. Very similar: leaves narrowly lan- ceolate, 4 inches long, on long petioles, villous, somewhat tomentose beneatli : peduncle inflated : flowers deep red : akene somewhat winged above with a thick narrow margin. — Chihuahua.

262 PROCEEDINGS OF THE AMERICAN ACADEMY

* * * Annuals (or n. 54 perennial), branching from the base, with leaves devel-

oped at the nodes in tlie axils of ordinary triangular bracts : flowers minutely glandular. — (§ Substipulata, Benth. Pseudo-stipulata, Torr. & Gray.)

53. E. ANGULOSUM, Benth. Floccose-tomentose, the branches mostly 4-6 angled : lower leaves orbicular to oblong-ovate, the upper oblong to oblanceolate : involucres hemispherical, very many-flowered : flowers rose-colored or greenish, J line long ; outer sepals ovate, concave, the inner longer, lanceolate. — California to Arizona and Utah.

54. E. Greggii, Torr. & Gray. Apparently perennial, puberulent : leaves spatulate, ciliate and somewhat villous, smooth above, acutish : involucres turbinate-campanulate, many-flowered : flowers purplish, the sepals ovate-oblong. — N. Leon, Mexico.

55. E. DiVARiCATUM, Nutt. Low, greyish pubescent : branches terete : leaves thickish, all rounded or the upper oblong, petiolulate : involucres very small and few-flowered : flowers whitish ; sepals oblong, nearly equal. — W. Wyoming and S. W. Colorado.

* * * * Tall stout white-tomentose annuals, with leafy simple stems, naked

above : inflorescence cymose : involucres turbinate-campanulate, shortly ped- unculate : flowers white, nearly glabrous ; sepals very unequal, the outer ovate- oblong or round-cordate. — (Sp. of § Corymbosa, Benth., Torr. & Gray.)

56. E. ANNUUM, Nutt. Leaves narrowly oblanceolate or oblong, attentiate to a short petiole, mostly flat : involucres densely white-to- mentose : flowers |- to 1 line long ; outer sepals oblong-obovate. — Colorado to W. Texas and Northern Mexico.

57. E. MULTiFLORUM, Beuth. Leaves lanceolate, sessile and some- what aiiricled at base, smoother above and margin undulate : involucres smoother: flowers 1^ lines long; outer sepals rounded cordate. — Arkansas, Louisiana, and Texas.

§ 3. Involucres cylindric-turbinate, more or less strongly 5-6-nerved, and often becoming costate or angled, with as many short erect teeth, sessile (rarely some of tliem pedunculate) in heads or clusters, or scattered in cymes or along virgate panicled branches, always erect, rather large (1 to 3 lines long) : bracts ternate, connate at base, usually short, acute and more or less rigid (sometimes more or less foliaceous) : flowers not attenuate at base : akenes usually glabrous. Mostly perennials, sometimes woody and leafy, more or less white-tomentose. — Oeegonium.

* Outer sepals broad and somewhat cordate, the inner much narrower : ces-

pitose densely toraentose perennials, with short closely branched caudex : involucres in a single head or short cymose umbel on the naked peduncle: ovary scabrous above. — (§ Heterosepala, Torr. & Gray, & sp. of § Vir- GATA, Benth., Torr. & Gray.)

58. E. OVALIFOLIUM, Nutt. Low, densely cespitose : leaves round or rarely oblong : bracts very small : involucres in a single close head :

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flowers rose-colored, white, or yellow ; outer sepals oblong, becoming orbitailar, the inner sjxatulate, often retuse. — Var. proliferum. In- volucres more or less cjmose-umbellate. E. proliferum, Torr. & Gray. — N. California to Colorado and British America ; frequent.

59. E. DiCHOTOMUM, Dougl. Caudex more diffuse : leaves oblan- ceolate, acute : lower bracts often foliaceous : inflorescence cymose- umbellate ; the involucres mostly solitary, about three lines long, strongly toothed: flowers white or pinkish ; outer sepals broadly elliptical, the inner linear-spatulate. — E. Greenel, Gray, Proc. Am. Acad. xii. 83. Oregon and N. California.

60. E. NIVEUM, Dougl. Like the last : most of the bracts more or less foliaceous and spreading : involucres usually shorter and broader, with some or all of the teeth jjroduced and often recurved : outer sepals round-oval, the inner obovate-spatulate. — Including E. strictum, var. lachnostegia, Benth., referred to the last in Torr. & Gray, Rev. 175. Washington Terr, to Oregon and Idalio.

* * Flowers narrower at base, the sepals similar and nearly equal: akenes smooth or nearly so.

-!- Perennials with short-branched caudex, naked peduncles, small bracts, and

capitate involucres (rarely solitary). *+ Heads solitary (few and umbelled in n. 66) : dwarf and cespitose, alpine or

subalpine, densely white-tomentose. — (§ Capitata, Torr. & Gray, excl. sp.)

61. E. Kennedyi, Porter, MS. Dwarf and very densely matted : leaves narrowly oblong, revolute, 1^^ to 3 lines long, densely tomeutose both sides : peduncles very slender and wiry, glabrous, 2 to 4 inches high: involucres 2 to 10, somewhat tomeutose, thick and strongly nerved, with short teeth, 1 \ lines long : flowers glabrous, wliite, veined with red, H lines long. — In the Sierra Nevada, Kern Co., California ; W. L. Kennedy, 1876.

62. E. KixGir, Torr. & Gray, excl. var. Dwarf and densely cespi- tose, villous-tomentose throughout : leaves oblanceolate or spatulate, an inch long or less, including the slender petiole : involucres thin and scarious, deeply toothed, villous, in dense heads : flowers rose-colored, glabrous. — N. Nevada.

63. E. PAUCiFLORUM, Nutt. Rather less densely cespitose, tomeu- tose throughout, or the linear-oblanceolate revolute leaves (2 inches long) glabrous above : involucres broadly turbinate, nearly glabrous, 2 lines long, thin, with broad somewhat scarious teeth : flowers white, glabrous. — Colorado.

64. E. ciiuYsoCEPHALUM, Gray, Proc. Am. Acad. xi. 101. Caudex more diffusely branched, woody : tomeutose throughout, the narrowly

264 PROCEEDINGS OF THE AMERICAN ACADEMY

oblanoeolate leaves (1 to 2 inches long) sometimes glabrate above : involucres narrower and rather more firm, 1| lines long, shortly toothed, somewhat tomentose : flowers yellow, glabrous. — E. Kingii, var. laxi- folium, Torr. & Gray, Rev. 165. Wahsatch Mountains.

65. E. MULTicEPS, Nees. Densely white-tomeutose throughout, rather diffusely branched at base : leaves narrowly oblanceolate, 1 or 2 inches long: peduncles 2 to 6 inches high : involucres rigid, narrowly turbinate, H to 2 lines long, with very short teeth; one of the bracts often foliaceous: flowers rose-colored, pubescent, a line long. — Ne- braska and Colorado.

66. E. SPATHULATUJi. Gray, Proc. Am. Acad. x. 76, Tomentose throughout, somewhat diffu^e at base, the stout peduncles (8 inches high) usually bearing a simple few-rayed umbel : leaves linear-oblanceo- late, 2 to 4 inches long: involucres rather broadly turbinate and I'igid, 2 lines long, with broad acute teeth : flowers white, glabrous, 2 lines long. — S. Utah.

++ ++ Peduncles mostly tall and stout, from a sparingly branclied caudex : heads solitary or few, in a long-jointed subumbellate cj-rae : flowers white or rose- colored. — (§ Capitellata, Torr. & Gray, and § Capitata, in part.)

67. E. LATiFOLiUM, Smith. Stout, tomentose throughout: pedun- cle not fistulous : leaves oblong to ovate : involucres tomentose, 2 lines long, in large dense heads (solitary, or few in a nearly simple umbel) : flowers glabrous. — E. nhlongtfolmm, Benth. ; Torr. & Gray, Rev. 167. Seashore, California.

68. E. NUDUM, Dougl. More slender, mostly glabrous above : pe- duncle fistulous or inflated : leaves broadly ovate to oblong, cordate or abruptly cuneate at base, glabrate above : involucres glabrous or nearly so, 2 or 3 lines long, in smaller and more numerous heads in a sparingly branched panicle : flowers glabrous or somewhat villous. — Var. pau- CIFLORUM. Involucres solitary or occasionally in pairs, much scattered. — Var. OBLONGiFOLiUM. Often somewhat tomentose throughout: leaves oblong, narrowed to a long slender petiole : bracts occasioually foliaceous : flowers usually somewhat pubescent. E. affine, Benth. — Washington Territory to S. California.

69. E. ELATUM, Dougl. Leaves large, villous-pubescent, ovate- oblong to lanceolate : peduncle (fistulous or inflated) and rigid panicle IJr to 3 feet high, smooth and glaucous : involucres glabrous, in clusters of 2 to 5 : flowers somewhat villous. — Washington Territory to N. California and W. Nevada.

•(- H- Stout woody perennials, more or less tomentose, virgately branched and very leafy : leaves small (9 lines long or less), shortly petioled and often

OF ARTS AND SCIENCES. 265

fascicled: bracts mostly foliaceous : involucres capitate or fascicled, the clusters more or less closely cj'mose-umbellate. — (§ Fasciculata, Benth., Torr. & Gray.)

70. E. ciNEREUM, Bentli. Leaves round to oblong, obtuse : pedun- cles elongated, sparingly dichotomous, with iew rather open heads : bracts short : flowers very villous. — Seacoast, S. California.

71. E. PARViFOLiUM, Smith. Leaves broadly ovate to oblong, acute: peduncles usually rather short, with few close heads: lower bracts conspicuous : flowers glabrous. — Near the coast, S. California.

72. E. FASCICULATUM, Benth. Leaves narrowly oblanceolate, acute, usually revolute, often glabrate above, much fascicled : peduncles short or elongated, bearing a short cymosely divided umbel, often much con- tracted or capitate : bracts more or less conspicuous : involucres pubes- cent or glabrate : flowers glabrous or often villous. — J^. ericcefolium, Torr. & Gray, Rev. 170. S. California to Arizona and S. Utah. Very variable.

^- 4- -t- Involucres mostly solitary (terminal and alar), in a repeatedly di- or trichotomous corj-mb-like cyme : leaves not fascicled : bracts small, very rarely foliaceous below. — (§ Corymbosa, Benth., Torr. & Gray, excl. sp.)

•w- Perennials, woody and diffusely much-branched, leafy below : leaves ovate- to oblong-oblanceolate or linear : sepals obovate, the inner emarginate.

73. E. MiCROTHECDM, Nutt. Low and rather slender, more or less white-tomentose : leaves usually narrow, revolute, becoming glabrate above: involucres usually small (f to 1| lines long), often pedun- culate: flowers a half to a line long. — Var. effusuji, Torr. & Gray. With very diffuse and repeatedly divided inflorescence. — Oregon and eastern base of Sierra Nevada to Nebraska and New Mexico ; the variety eastward.

74. E. C0RYMB0SD>i, Benth. Stouter and more rigid, usually densely tomentose : leaves broader and less revolute : umbel stifl\, broadly cymose : involucres mostly sessile, 1 to 2 lines long : flowers a line or two long. — Including E. microthecum, var. Fendlerianum, Benth., Torr. & Gray. Of nearly the same range and hardly distinct.

++ *+ Perennials, less woody and more shortly branched at base : leaves mostly narrow : sepals nearly equal.

75. E. Thompsons, "Watson in Am. Naturalist, vii. 302. Stout and rio-id, erect, a foot high, yellowish, glabrous above the tomentose base: leaves obovate-oblong, densely tomentose beneath, glabrate above, on long petioles : involucres 2 lines long : flowei-s yellow, 1^ lines long. — S. Utah.

266 PROCEEDINGS OF THE AMERICAN ACADEMY

76. E. BREVICAULE, Nutt. More lax and slender, glabrous or glabrate above the white-tomentose base : leaves linear to narrowly oblanceolate, 1 to 3 inches long, attenuate to a very short petiole, often revolute, sometimes glabrate above: involucres 1| lines long, nearly glabrous : flowers yellow, a line long. — Idaho and Wyoming to New Mexico.

77. E. LONCHOPHYLLUM, Torr. & Gray. Described as taller than the last (a foot high or more), with a loose panicle-like cyme ; leaves lanceolate to broadly linear, 3 inches long and attenuate into a petiole an inch long or more : flowers white, few in the involucres. — New Mexico, only by Dr. Newberry.

1-t- •»-+ ++ Annuals : leaves mostly rosulate at the base, a whorl rarely subtend- ing the umbel : peduncle short.

78. E. TRUNCATUM, Torr. & Gray. Slender, a foot high or less, floccose-woolly throughout : leaves oblanceolate, an inch long : umbel leafly-bracted, of 4 to 6 elongated once or twice divided rays : involu- cres tomentose, oblong-turbinate, 2 lines long : flowers rose-colored, a line long. — Near Mount Diablo, California ; W. H. Brewer.

79. E. MoHAVENSE. Very slender, glabrous except at the base: leaves round or ovate, tomentose, small : umbel naked, of 3 or more repeatedly divided rays : involucres glabrous, broadly turbinate, a line long : flowers yellow, very small (scarcely a half line long), abruptly narrowed at base. — Mohave Valley ; Dr. Edward Palmer, 1876.

80. E. Lemmoni. Rather stout, a span high, more or less hirsute with very short spreading hairs, not at all tomentose : leaves orbicu- lar-reniform, 6 to 9 lines broad, on slender petioles : peduncle fistulous or inflated, bearing a naked 3-rayed narrow umbel, twice or thrice divided: involucres glandular-pubescent, rather broadly turbinate, 1^ lines long : flowers pale rose-color, half a line long, with narrow sejmls. — On sand hills near Reno, Nevada; J. G. Lemmon, 1876. A very peculiar species.

-1- -4- -I- ^- Involucres sessile and solitary (often secund) along the ascending and usually long-virgate branches of the open naked dichotomous panicle : lowest bracts rarely foliaceous : flowers glabrous (except in n. 89). — (§ Vikgata, Benth., Torr. & Gray, excl. sp.)

++ White-tomentose perennials, leafy below : panicle sparingly branched, usu- ally virgate : involucres tomentose, the teeth not margined: flowers white or rose-colored.

81. E. Wrightii, Torr. Much branched and usually very leafy at base, rather slender : leaves oblong- to linear-oblanceoiate, acute, an inch long or less : bracts all small, triangular : involucres and flowers

OF ARTS AND SCIENCES. 267

1 to li lines long: akene scabrous above, very acute at base. — Cali- fornia to New Mexico. Variable ; inflorescence in subalpiue specimens at times reduced to a very few nearly capitate involucres.

82. E. SAXATiLE. Biennial or perennial (?), sparingly branched and very leafy at base, rather stout, a foot high or less : leaves rounded or obovate, obtuse, 6 to 8 lines broad or less, cuneate at base upon a short thick petiole, densely tomentose both sides : branches of the cymose panicle short and somewhat spreading : bracts larger, subfolia- ceous, triangular to acute-oblong: involucres and flowers 1^ to 2 lines long: sepals apj^ressed to the nearly glabrous akene, which is more abruptly narrowed at base. — On rocks above San Bernardino (Dr. C. C. Parry, 1876), and in the Santa Lucia Mountains, Dr. E. Palmer.

83. E. STRICTUM, Benth. Very slender, glabrate above : branches of caudex very short : leaves small, ovate to oblanceolate, on long slender petioles : panicle twice or thrice divided, with 1 to 3 involucres on the short branches : bracts short, the lower somewhat elongated : flowers and glabrate involucres 1^ lines long. — Blue Mountains, Oregon.

84. E. RACEMOSUM, Nutt. Sparingly or not at all branched at base, stout, 1 to 3 feet high: leaves large (1 to 2|- inches long), ovate or oblong, on long petioles : lower bracts somewhat foliaceous : invo- lucres approximate upon the few strict branches of the once or twice forked panicle : flowers 2 lines long. — Utah to New Mexico.

85. E. ELONGATUM, Benth. Sparingly branched at base, a foot or two high : leaves usually scattered, smaller, lanceolate to ovate, on short petioles : bracts rarely elongated : involucres 2^ to 3 lines long, obtusely toothed, distant on the few elongated branches of the panicle. — S. California, near the coast.

++ -w- Perennials, woody and leafy below : panicle diffuse with short and rigid branclilets : involucres short, with rounded and more or less membranously margined teeth ; bracts very small.

86. E. Heermanni ; Dur. & Hilg. A foot high, soon glabrate above, divaricately dichotomous, the branclilets somewhat spinescent : leaves oblanceolate, ^ inch long, on slender petioles : involucres few and dis- tant, campanulate, a line long : flowers rose-colored or yellowish, 1 J lines long. — S. California, Nevada.

87. E. Palmeri. More tomentose throughout, and usually taller : leaves oblanceolate, ^ inch long, on short petioles : branches somewhat flexuous, mostly alternately divided, the short branclilets divaricate or deflexed, very short-jointed : involucres rather numerous, narrowly tur- binate, a line long, nearly glabrous : flowers a line long, reddish white;

268 PROCEEDINGS OF THE AMERICAN ACADEMY

outer sepals ciineate-obovate, the inner slightly narrow : akene some- what pubescent, — San Diego County, California, and in S. Utah; Dr. Edward Palmer.

H-c -w. -w Annuals : leaves usually rosulate at tiie base, and occasionally occur- ring at the nodes.

= Tomentose throughout : branches of the panicle virgate, sparingly divided : involucres narrow, 2 lines long.

88. E. viRGATUM. Benth. A foot or two high : leaves oblanceo- late : branches elongated, ascending : flowers glabrous, a line long, white, reddish, or yellow. — California ; variable, verging upon JE. vim- ineuiifi.

89. E. DASTANTHEMUM, Torr. & Gray. Shorter, more slender : leaves rounded, somewhat scattered : panicle more branched, rather diffuse : involucres very narrow : flowers a line long or less, somewhat villous. — N. California.

= = More slender and diffuse, glabrous or somewhat tomentose : involucres smaller, narrow or turbinate.

90. E. viMiNEUM, Dougl. Rather diffuse, the branches often elongated, usually somewhat tomentose, at least below the panicle : leaves i-ounded to broadly ovate: involucres IJ lines long, narrow and often contracted above : flowers rose-colored, or yellowish, a line long or more. — Washington Territory to N. Nevada and S. California ; variable.

91. E. Baileyi, Watson, Proc. Am. Acad. x. 348. Very diffusely much-branched, glaucous and glabrous : leaves round to broadly ovate, densely tomentose : involucres .a line long or usually less, mostly wider above with obtuse teeth : flowers |^ to f line long. — Var. tomen- TOSUM. Loosely tomentose throughout : bracts more linear : involucres broadly turbinate, deeply toothed. — N. W. Nevada to S. California and Arizona. ''■

92. E. gracile, Benth, Usually more strict and narrowly pani- cled, more or less tomentose throughout: leaves oblanceolate or ob- lonor : bracts more or less elongated or foliaceous, the lower often including one or more leaves: involucres a line long or less, broader above, with rigid acute teeth: flowers f line long. — S. California; very variable.

93. E. POLYCLADON, Benth. Stouter, white-tomentose throughout, the stem leafy its whole length : panicle erect and elongated : leaves oblong-lanceolate : sepals narrower at base and bracteoles much more villous. — Arizona and New Mexico.

OF ARTS AND SCIENCES. 2Qd

94. E. Plumatella, Dur. & Hilg. Low, grayish tomentose throughout: intrioately much-branclied from the base, leaves rounded: involucres i line long or less: flowers | to at length 11 lines long, the sepals broadly cuiieate-obovate and refuse. — N. W. Nevada to S. California.

95. E. IXTRICATUM, Benth. Leaves rounded and viscid-pubescent : panicle diffuse with numerous short divaricate branchlets, glabrous or glabrate : involucres very small, glabrous: flowers minute, sparingly pubescent. — Lower California.

CHORIZANTHE, R. Br. A polymorphous genus, with which it seems necessary to unite Centrostegia as too closely related to the section Mucronea to be kept distinct. The character upon which that genus mainly rested, the spurs at the base of the involucre, is of fre- quent occurrence in the Chilian Chorizanthe commissuralis, which is without doubt a true Chorizanthe. Moreover, the involucres and spurs in the two recognized species of Centrostegia are very different in char- acter, and in some of the 3Iucronea species the angles of the involucres are frequently rather strongly gibbous at base, showing a tendency towards a like peculiarity. The known species, excepting the peren- nials of Chili, are the following : —

§ 1. Glabrous or glandular, not villous or tomentose, with radical spatulate leaves and ternate foliaceous more or less connate bracts : involucres in open dichotomous panicles, coriaceo chartaceous, the awns not uncinate : flowers 6-parted, soft-pubescent, on slender pedicels : stamens 9, inserted at the base. — Mucronea. S.California.

* Involucres 1-3 flowered, with 3 to 6 mostly erect teeth and 3 to 6 divaricate cuspidate or awned spurs at base: bracts small. — (Centrostegia, Gray.)

L C. Thdrbkri. Involucres chartaceous and triangular, with 3 to 5 broad short teeth, and 3 broad straight spurs. — Centrostegia Thurbert, Gray.

2. C. LEPTOCERAS. Livolucres coriaceous, deeply 4-6-cleft, the lobes rigid and attenuate, and with as many rigid usually uncinate awn- like spurs. — Centrostegia leptoceras, Gray.

* * Involucres l-flowered, with 2 to 5 stout divergent teeth, not spurred : bracts conspicuous. — ( Mucronea, Benth. § Mucronea, Torr. & Gray. )

3. C. PERFOLIATA, Gray. Sparingly glandular-hirsute: bracts per- foliate : involucres scattered : sepals laciniate.

4. C. Califorxica, Gray. More hirsute : bracts unilateral : in- volucres often cl^astered: sepals entire.

270 PROCEEDINGS OF THE AMERICAN ACADEMY

§ 2. Villous-pubescent or hirsute, not glandular, fragile : bracts 1 to 3, distinct, at least the uppermost acicular-subulate : involucres more or less clustered or capitate, coriaceous, 1-flowered, 6-angled and tootlied, the divergent teeth often uncinate : flowers mostly 6-cleft, nearly sessile, glabrous or bristly- villous on the midveins (pubescent in n. 5) : stamens mostly 9, inserted below the middle. — Euchorizanthe, Torr. & Gray.

* Involucres subcapitate ; margins of the teeth mostly scarious : stems more or less leafy and bracts foliaceous.

■1- Teeth united by a petaloid margin (except in the alar involucres) : stems erect : heads few and dense.

5. C. MEMBRANACEA, Beuth. Floccose-tomentose, slender, leafy : leaves linear : scarious limb of the involucre at length broadly dilated : flowers as in the preceding section ; the sepals spatulate : stamens at the base. — Mendocino County to San Luis Obispo.

6. C. STELLULATA, Beiith. Low, hirsute : leaves liuear-oblanceo- late, scattered : involucres 2 or 3 lines long ; margin of the teeth narrower : flowers glabrous, sessile, 2^ lines long, equally 6-cleft ; segments obcordate. — Sacramento Valley ; only from Hartvveg.

7. C. DouGLASii, Benth. Similar, but leaves in 1 or 2 whorls: involucres 1^ lines long: flowers shortly pedicelled, a line long; seg- ments truncate, the outer cuspidate, the inner shorter and retuse. — Near Monterey (?) ; only from Douglas.

H- -1- Teeth distinct, scariously margined or herbaceous : usually more diffuse and decumbent, villous-pubescent, with more numerous scattered heads. •w- Slender and mostly decumbent : involucres and flowers 1 to 1^ lines long.

8. C. DIFFUSA, Benth. Leaves narrowly spatulate, an inch long or less : bracts short, acerose : involucres and flowers a line long, the teeth long-awned and broadly scarious : calyx-segments oblong, nearly equal, the inner slightly narrower. — Near Monterey.

9. C. Breweri. Ascending or erect, 2 to 4 inches high, softly pubescent : leaves ovate or rounded, 3 to 6 lines broad, on slender petioles : bracts foliaceous, linear-oblanceolate, pungent : involucres and flowers 1^ lines long, the short slightly unequal teeth united at base by an inconspicuous margin, stout and curved, shortly awned : flowers glabrous or villous ; segments broadly oblong, the inner ones shorter : stamens at the base. — On dry rocky hillsides at San Luis Obispo and in San Margarita Valley ; collected by Prof. W. H. Brewer.

10. C. PUNGENS, Benth. Decumbent or at first erect: leaves oblanceolate, mostly opposite: bracts foliaceous: involucres 1^ to 2 lines long, the unequal teeth usually margined : calyx-segments short, equal, oblong. — San Francisco and southward, common.

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++ ++ Stouter, erect : bracts foliaceous : involucres and tiowers 2 to 2^ lines long.

11. C. VALiDA. Mostly stout, 6 inches high or less, sparingly branched : leaves oblanceolate, an inch long, the bracts similar : in- volucres in rather close heads, 2h to 3 lines long; teeth nearly equal, slightly si)i'eading with straight awns, scarcely margined : flowers 2^ lines long, villous or glabrous ; segments oblong, very unequal, the shorter ones erose : stamens adnate to the middle of the tube or nearly to the top. — Specimens in herb. Gray are from the '' Rus- sian Colony " (from herb. Acad. St. Petersb.), and also collected by Rev. Mr. Samuels, probably in the same region.

12. C. Palmeri. Stout and branching, a span high or less: leaves spatulate, 2 inches long : bracts oblanceolate, conspicuous : involucres in large close cymes, 2 lines long ; teeth not margined, slightly diver- gent, one long-awned, the rest nearly equal : flowers glabrous, broadly lobed ; outer segments rounded, entire, the inner shorter, truncate or bifid, shortly laciniate : stamens near the base. — Near San Luis Obispo; Dr. Edward Palmer, 1876 (n. 464).

» * Involucres at length scattered or only loosely cymosely clustered ; teeth unequal, not margined.

■t- Calyx-segments lanceolate, fimbriate : leaves all radical : bracts not folia- ceous : villous-pubescent or glabrate. — S. California.

13. C. FiMBRiATA, Nutt. Segments coarsely fringed below the obtuse summit.

14. C. LACiNiATA, Torr. Segments long-acuminate, copiously fringed.

■t- I- Calyx-segments short, oblong, entire. ++ Bracts not foliaceous.

15. C. STATICOIDES, Bentli. Erect, often a foot high, branching above: leaves oblong, tomentose beneath: involucres 1^ to 3 lines long, alternate teeth often much enlarged: flowers rose-colored, 2 to 2^ lines long, glabrous ; segments oblong, the inner ones nearly a half shorter. — Monterey to San Diego.

16. C. PROCUMBENS, Nutt. Slender, procumbent, diffusely branched from the base : leaves spatulate, not tomentose : involucres 1 to 1 ^ lines long: flowers yellowish, 1;^ lines long, with equal narrowly oblong segments. — San Diego.

t-f -w- Bracts more or less foliaceous : flowers 1^ lines long: branched from the base.

17. C. Parryi. Small, villous-pubescent, leafy: leaves narrowly

272 PROCEEDINGS OF THE AMERICAN ACADEMY

oblanceolate, not tomentose, an inch long : lower bracts as large, simi- lar: tube of involucre a line long, tlie very divergent alternate teeth as long or longer : flowers white or pinkish, villous ; segments recurved, somewhat undulate, oblong-ovate, crenate, acutisli, the inner narrower, scarcely shorter : stamens 9. — Common on gravelly mesas near Crof- ton, San Bernardino County; Dr. C. C. Parry, 1876.

18. C. Xanti. Small, villous-pubescent and tomentose : the leaves ovate-oblong, 2 to 6 lines long, tomentose beneath : lower bracts simi- lar or linear-oblanceol ale : involucres tomentose, in diffuse cymes, the tube 2 lines long ; teeth very divergent, often half as long or more, the alternate ones much smaller : flowers rose-colored, 2^ lines long, vil- lous ; segments linear-oblong, entire, acutish, the inner a half shorter : stamens 6 (rarely 7 or 8.) — C. procumbens, Gray, Proc. Bost. Soc. vii. 148; referred to C staticoides, in Torr. & Gray, Rev. 195. Near Fort Tejon (C. L. Xantus, Dr. Horn) ; San Bernardino and San Gor- gonio, on sandy washes, Dr. C. C. Parry.

19. C. Wheeleri. Small, villous-pubescent and tomentose : leaves and bracts tomentose beneath, the latter oblanceolate, an inch long or less : involucres in small cymes, nearly glabrous, a line long, with short stout teeth, the alternate ones smaller: flowers rose-colored, \\ lines, long, glabrous ; segments broadly oblong, the inner slightly shorter and broader : stamens 6. — Near Santa Barbara ; Dr. J. T. Rothrock, on Lieut, G. M. Wheeler's Geogr. Survey, 1876.

20. C. UNiARiSTATA, Torr. & Gray. Villous-pubescent : leaves and bracts spatulate or oblanceolate : involucres numerous, scattered ; one tooth with a long straight awn, the rest short and uncinate: flowers yellowish, \\ lines long; segments very unequal, the outer obovate, entire, the inner oblong, crenate: stamens 3 or 9. — S. Cali- fornia; near New Idria (Prof. Brewer), and on the Ui^per Salinas, Dr. Palmer.

21. C. BREVICORNU, Torr. Pulverulent or nearly glabrous, erect or ascending, very fragile at the tumid nodes : leaves and bracts broadly spatulate to linear-oblanceolate : involucres scattered, narrow ; teeth very short, uncinate: flowers included; segments narrowly oblong, nearly equal : stamens 3 or 6. — N. W. Nevada to S. E. California and S. Utah.*

§ 3. Villous-pubescent and tomentose, low, branching and fruiting from the base : bracts 2 or 3, distinct : involucres scattered, coriaceous, 1-flowered, unequally 3-5-tootlied or -lobed, triangular or C3'iindrical, transversely cor- rugated : flowers tubular, shortly and equally 6-cleft, glabrous : stamens G or 9, short, on the throat. — Acanthogonum, Torr. & Gray.

OF ARTS AND SCIENCES. 273

* Involucres broadly triangular : bracts foliaceous : flowers nearly sessile.

22. C. POLTGONOIDES, Torr. & Gray. Decumbent, villoiis-pubes- cent: leaves and bracts narrowly oblanceolate ; floral bracts very short : involucres 3-costate, with 3 stout broad divergent uncinate teeth, exceeding the (1 line tube) long. — Near Placerville, California; only by Rattan.

23. C. KiGiDA, Torr. & Gray. Erect, low, dense, becoming rigid and persistent : leaves and bracts ovate, tomentose beneath ; floral bracts linear-subulate, stout and spinescent, 6 to 15 lines long: in- volucres 6-costate, with 3 very unequal lanceolate carinate spinescent or pungent teeth. — N. W. Nevada to S. E. California and S. Utah.

* * Involucres cylindrical : bracts not foliaceous, subulate-setaceous : flowers on slender pedicels : leaves tomentose beneath : low.

24. C. CORRUGATA, Torr. & Gray. Leaves ovate : the involucres strono-ly corrugated, 8-toothed : flowers white, included : stamens on the middle of the tube. — Valley of the Lower Colorado.

25. C. Watsoni, Torr. & Gray. Leaves narrowly oblanceolate : bracts rarely foliaceous : the involucres obscurely corrugated, very un- equally 5-toothed : flowers yellow, slightly exserted. — N. Nevada to S. E. California.

OxTTHECA iNERMis. Low and slender: leaves broadly oblanceo- late, glabrous, with scabrous-ciliate margin : bracts linear-oblong, united only at base, acute without awns, 2 or 3 lines long : involucres shortly pedicelled, 4-parted nearly to the base, the oblong-lanceolate lobes nearly equal, acute without awns, a line long : flowers rose-colored, half a line long ; sepals oblong, the inner smaller and retuse. — Cali- fornia, probably on Mount Diablo : collected only by Miss M. J. Ban- croft. Remarkable for the total absence of awns, but otherwise with the characters of the genus, and nearly allied to 0. dendroidea, Nutt.

Amarantus (Pyxidium) blitoides. Prostrate or decumbent, the slender stems becoming a foot or two long, glabrous or neaily so : leaves broadly spatulate to narrowly oblanceolate, attenuate to a slender petiole, an inch long or usually less : flowers in small contracted axil- lary spikelets : bracts nearly equal, ovate-oblong, shortly acuminate, 1 to 1^ lines long, little exceeding the oblong obtuse and mucronulate or acute sepals : utricle not rugose, slightly longer than the sepals : seed nearly a line broad. — Frequent in the valleys and plains of the interior, from Mexico to N. Nevada and Iowa, and becoming intro- duced in some of the Northern States eastward. It somewhat resem- bles the A. Blitum, Linn., of the Old World, and has been mistaken

VOL. XII. (N. S. IV.) 18

274 ^PROCEEDINGS OF THE AMERICAN ACADEMY

for it ; but that species is usually erect, with shorter and more scarious bracts, and a smaller seed more notched at the hilum. The allied A. albus, Linn., also common and indigenous throughout the interior, is distinguished by its usually erect dilFusely branched habit : rhachis of the spikelets often somewhat elongated (^ to 3 lines long) : bracts subulate, rigid, pungently awned, 1 to 2| lines long, the lateral ones very much smaller or wanting : sepals oblong-lanceolate, acuminate, shorter than the slightly rugose utricle: seed smaller (| line broad). It is very abundant on the western prairies, where it is populai-ly known as "rolling" or "tumble-weed," the stem breaking off at the root when dry and the compact top rolling before the wind to any distance.

Amaranths (Amblogyne) Pa.lmeri, Dioecious, rather stout, erect, 2 or 3 feet high, branching, somewhat pubescent above or glab- rate : leaves oblong-rhomboid, an inch or two long and about equalling the petiole, the upper linear-lanceolate : flowers in close elongated linear spikes, leafy at base : bracts solitary, mostly twice longer than the flowers, spreading, subulate and rigid, narrowed into a stout awn : sepals of fertile flowers distinct or nearly so, 1 to 1 J lines long, oblong and somewhat broader above, obtuse or retuse, two or three usually slightly larger and more acute or setaceously apiculate : stigmas usually 2 : utricle circumscissile. — At Larkin's Station, San Diego County, California, by Dr. E. Palmer (n. 323 of his collection) ; also on the banks of the Rio Grande, by Berlandier (n. 2407) in 1834. Staminate flowers have not been detected among the fruiting speci- mens, but what is probably to be considered the sterile form has been found by various collectors from the Rio Grande through Arizona to S. California and Cape St. Lucas. These accord in habit and foliage with the pistillate plants, and have very narrowly acuminate or seta- ceous pungent bracts, equalling or usually exceeding the lanceolate long-acuminate sepals. An examination of all our species of the group seems to fully justify the reference by Mr. Bentham of the genus Arnblogyne (including Sarratia) to Amarantus. To the A. jimhriatus, A. Torreyi, &c., of the same region, the following species from the mouth of the Rio Grande may be added : —

Amaranths (Amblogyne) Greggii. Dicecious, erect, glabrous or nearly so : upper leaves rhombic-ovate, an inch long or less, on short petioles, rather thick and somewhat scabrous : spike elongated, leafy and interrupted at base : bracts solitary, lanceolate, acuminate, scarious, erect, much shorter than the fruiting calyx: sepals distinct, \^ lines long, oblong-spatulate, acute, the inner ones somewhat the narrower below : stigmas 3 : utricle a little shorter, thin and not circumscissile : seed

OF AETS AND SCIENCES. 275

^ line broad. — Collected by Dr. Gregg near the mouth of the Eio Grande, in 1848 — only pistillate specimens.

Amaranths (Euamarantus) Wrightii. Glabrous, erect and slender, with ascending branches and spikes, 2 or 3 feet high or more, reddish : leaves small and thin, the upper ones but an inch long, on slender petioles, oblong to narrowly lanceolate : terminal compound spike erect, narrow, and rather leafy : bracts solitary, subulate, rigid, attenuate into a pungent awn, about 1|^' lines long: sepals ^ to nearly 1 line long, oblong to oblong-spatulate, obtuse, sometimes emarginate : utricle about equalling the sepals : seed orbicular, h line broad. — Collected at the Copper Mines, New Mexico, by Mr. Wright (n. 1748, in part), October, 1851 ; also in the Upper Arkansas Valley, by Messrs. Wolf & Rothrock (n. 275) in 1873. Approaching the section Amhiogyne in the characters of the calyx.

A5IARAXTUS (Euamarantus) obovatus. Pubescent, slender, erect, 2 feet high, reddish, sparingly branched: leaves small, 1 to 1^ inches long, lanceolate, on short slender petioles : spikes erect, narrow, the terminal ones an inch or two long, the axillary shorter : bracts subulate, acuminate and pungent, 1^ to 2 lines long, much exceeding the unequal narrowly oblong acute sepals : utricle equalling the calyx : seeds oblong-obovate, f line long. — Also collected by Mr. Wright and in the same locality, and distributed under the same number ; referred in Bot. Mex. Bound, to A. hybridus. Remarkable in the shajje of the seed.

Atriplex decumbens. Decumbent or procumbent, slender and branching from the base, densely hoary-scurfy, the stems becoming somewhat woody below : leaves mostly opposite, oblong-ovate, sessile, acute or acutish, cuneate or obtuse at base, ^ to 1 inch long or less : staminate flowers in dense clusters in short interrupted terminal spikes ; calyx 5-cleft: fruiting bracts coriaceous, compressed, united to above the middle, triangular-cordate, acute, 2 lines long and broad, entire or slightly denticulate, not herbaceously margined nor the sides muricate : seed nearly a line long. — Near San Diego; Dr. E. Palmer, 1876 (n. 334). Allied to A. leiicophylla, Dietr.

Corallorhiza Bigelovii. Scape stout, 6 to 15 inches high: sepals and petals oblong, obtuse, about 4 lines long, twice longer than the column, purple and veined (not spotted) ; lateral sepals oblique and with the base of the column strongly gibbous over the top of the ovary ; lip entire, fleshy, darker colored and strongly veined, deeply concave, elliptical, broad and somewhat auricled at base, with two thick laminae ; spur none : column rather slender, broadly margined

2T6 PROCEEDINGS OF THE AMERICAN ACADEMY

below : capsule oblong-ovate, 6 to 9 lines long, shortly attenuate to a short pedicel, — G. striata, Torrey, Pac. R. Rep. iv. 152, t. 25. In the Sierra Nevada and mountains of N. California. Recognized by Dr. Torrey as distinct from C. MacrcBi, which is doubtless identical with the original C. striata of Lindley. The figure cited fails to represent the gibbosity of the perianth. C. striata is very similar, but with the flowers still larger (often 6 or 7 lines long) ; lip rather less fleshy, somewhat narrower below, reflexed above the base, and bearing the prominent laminie upon the arch : ranging from Washing- ton Territory and Oregon to the Great Lakes.

Habenaria sparsiflora. Stem rather slender, a foot or two high, leafy : leaves narrowly lanceolate, acutish or acute : bracts linear- lanceolate, acuminate, usually much exceeding the greenish flowers, which are few (10 to 20) and distant : perianth thin and delicate, apparently spreading: sepals 3-nerved, the lateral ones oblong or lanceolate, 2 or 3 lines long, the upper ovate and a little shorter : lip several-nerved, narrow, linear or lanceolate, 3 or 4 lines long, nearly equalling the narrow sjjur : anther emarginate ; stalks of the pollen^ masses very slender : glands orbicular : beak of stigma broadly tri- angular : capsule oblong, sessile, 6 lines long. — H. Thurheri, var.. Gray, Proc. Am. Acad. vii. 389. Common in the Sierra Nevada and mountains of Northern California ; marked by its peculiar habit. The typical H. Thurheri is to be referred to H. leucostachys.

Habenaria pedicellata. Stem leafy : raceme loose, 20-30-flow- ered, with linear-lanceolate bracts shorter than the long-pedicellate flowers : sepals 3-nerved, 2h lines long, oblong, the upper ovate ; lip fleshy, several-nerved, oblong-lanceolate, half broader at base, 3 lines long ; spur filiform, twice longer than the sepals : pollen-masses at- tached to the oblong glands by a short thick pedicel: beak of stigma ovate-triangular, prominent : capsule ovate-oblong, 4 lines long, attenu- ate into a slender pedicel about as long. — A single specimen of this very distinct species was collected by Prof. W. H. Brewer (n. 1453, in part) in the Shasta Mountains, California ; September.

Habenaria Cooperi. Stout and tall (3 feet high), leafy : flowers numerous, spicate, yellowish green : sepals and petals nerveless, con- nivent at base, rather thick, equal, 2 lines long ; lateral sepals oblong, the upper ovate ; lip ovate, truncate at base, with a broad claw ; spur short and thick : glands orbicular : beak of stigma triangular : capsule oblong, sessile, 4 or 5 lines long. — On clay hills near San Diego, Cali- fornia ; Dr. J. G. Cooper. A strongly marked species, allied to H. hyperhorea, R. Brown. Of the other western species of this genus,

OP ARTS AND SCIENCES. 277

H. Unalaschcensis (Spiranthes Unalaschcensis, Spreng.,and H. Schisch- mareffiana, Cham.) must include H. foetida, Watson (Platant/iera, Geyer), and Gymnadenia longispica, Dunind. Liudley's Platanthera striata is to be referred to H. gracilis (^Platanthera gi-acilis, Lindl.), distinguished by its short saccate spur.

SiSYRiNCHiUM BELLUM. Stems ancipital, ^ to 2 feet high or more, smooth or scabrous on the narrow margins, of a single node or often with 2 or 3 nodes, each node bearing 1 to 4 (usually 2) peduncles : leaves a line or two wide, shorter than the stem ; peduncles 2 to 4 inches long, usually about equalling the nodal bract : spathes of two mostly nearly equal bracts, a half to an inch long, scabrous on the keel, 4— 7 -flowered : segments of perianth about 6 lines long, broad, 3-toothed or sometimes mucronate, light purple, darker below and yellow at base, somewhat pubescent, as also the ovary : stamineal column 3 lines long, purplish, pubescent at base : capsule depressed-globose or -obovoid, 2 or 3 lines long; cells about 10-seeded: seeds irregularly and obtusely angled, roughened, f line in diameter. — Common through- out California and to the Columbia River ; the western equivalent of S. anceps, Linn., in the Atlantic States. It strongly resembles the latter species, differing in its generally stouter habit, broader foliage, and larger flowers, in its less mucronate petals, and in its twice larger seeds. It occasionally occurs with scapelike stems bearing a single spathe, simulating the eastern S. mucronatum, Michx., which is distin- guished by its low and usually very slender habit, the scape always terminated by a single spathe sessile within the terminal longer bract, the flowers small with segments setosely mucronate, and capsules glo- bose ; the size of the seeds is about the same in both. The two eastern species are distinct from the Linnean *S. Bermudianiun, as plainly ap- pears on comparison with specimens from the Bermudas kindly furnished by Governor Lefroy. These have a very stout broadly winged branching stem, with leaves 3 lines wide, broad spathes, larger flowers (6 to 9 lines long), and obovate capsules 3 lines long. The Texan S. minus, Engelm. & Gray, referred to S. Bermitdianum by Klatt, is even more distinct, with its low slender very branching habit, small red flowers, oblong capsules, and minute round seeds. There are indica- tions of other species to be found in Florida and the western Gulf States.

Erythronium purpurascens. Leaves undulate, oblong- to narrowly lanceolate, 4 to 6 inches long : scape low, often stout, occasionally di- vided, racemosely or somewhat umbellately 4-8-flowered or more ; pedicels very unequal, the upper becoming 2 to 4 inches long : flowers

278 PROCEEDINGS OF THE AMERICAN ACADEMY.

light yellow, more or less tinged with purple, deep orange at base ; the lanceolate segments spreading, 9 to 12 lines long: anthers oblong, 1^ to 2 lines long, yellow, on very slender filaments : style thickened above, o-lobed at the summit : capsule erect, narrowly oblong and ob- tusely triangular, faintly nerved, 1;^ inches long. — E. grandijlorum, var. multijiormn, Torrey, Pac. R. Rep. iv. 90 ; Baker, Journ. Linn. Soc. xiv. 298. In the Sierra Nevada : near Downieville, Sierra Co. (Dr. J. M. Bigelow), and frequent in Plumas Co., whence fine speci- mens have been received from Mrs. M. E. Pulsifer Ames and from Mrs. R. M. Austin. Abundantly distinct from E. grandijlorum, and a very pretty species, well deserving cultivation.

PllOCEEDIXGS.

Six hundred and ninety-second Meeting.

May 30, 1876. — Annual Meeting.

The Peesident in the chair.

The Corresponding Secretary read letters from the follow- ing gentlemen : Professor W. D. Whitney, offering the thanks of the American Oriental Society for the use of the hall of the Academy ; Dr. Thomas Andrews, expressing his thanks for the gift of the " Works of Rumford ; " Messrs. Stewart and Rowland, accepting their election as members of the Academy ; and Mr. George S. Hillard resigning his Fellow- ship.

The Treasurer presented his annual report, which was accepted and ordered to be entered on the records.

The Librarian jjresented his report, which was accepted.

Professor Cooke presented the report of the Rumford Committee, which was accepted. In accordance with a sug- gestion contained in this report, it was

Voted, To jolace six hundred dollars ($600) of the Rum- ford fund at the disposal of the Rumford Committee to aid Professor H. A. Rowland in a determination of the mechan- ical equivalent of heat.

The President announced the death of Christian Lassen, Foreign Honorary Member.

On the motion of the Treasurer, it was

Voted, To appropriate from the general fund : —

280 PROCEEDINGS OF THE AMERICAN ACADEMY

For general expenses 12,100

For Library expenses 700

For Publications 1,500

The following gentlemen were elected members of the Acad- emy : —

William Edward Story, of Somerville, to be a Resident Fel- low in Class L, Section 1.

Bennett Hubbard Nash, of Boston, to be a Resident Fel- low in Class III., Section 2. '

Alfred Tennyson, of Freshwater, to be a Foreign Honorary Member in Class III., Section 4, in place of the late Mar- chese Giho Capponi.

Francois Auguste Alexis Mignet of Paris, to be a Foreign Honorary Member in Class III., Section 3.

Ernst Curtius, of Berlin, to be a Foreign Honorary Mem- ber in Class III., Section 3.

Sir Henry Creswicke Rawlinson, of London, to be a For- eign Honorary Member in Class III., Section 2, in place of the late Christian Lassen.

Arthur Penrhyn Stanley, of Loudon, to be a Foreign Hon- orary Member in Class III., Section 3.

Eugene Emmanuel Viollet-Le-Duc, of Paris, to be a For- eign Honorary Member in Class III., Section 4, in place of the late Joaquim Jose da Costa de Macedo.

Mark Pattison, of Oxford, to be a Foreign Honorary Mem- ber in Class III., Section 3, in place of the late Jean Baptiste Benoist Eyries.

Thomas Hill, of Portland, to be an Associate Fellow in Class L, Section 1.

George Mary Searle, of New York, to be an Associate Fellow in Class L, Section 2,

Henry Larcom Abbot, of New York, to be an Associate Fellow in Class I., Section 4.

Nathaniel Holmes, of St. Louis, to be an Associate Fellow in Class III., Section 1.

Richard Saltonstall Greenough, of Floi'ence, to be an Asso- ciate Fellow in Class HI., Section 4.

OF ARTS AND SCIENCES. 281

The annual election resulted in the choice of the following officers : —

Charles F. Adams, President.

Joseph Lovering, Vice-President.

JosiAH P. Cooke, Jr., Corresponding Secretary.

Edward C. Pickering, Recording Secretary.

Edmund Quincy, Treasurer and Librarian.

Council. John B. Henck, \ WoLCOTT GiBBs, \ of Class I.

Charles W. Eliot, )

Alexander Agassiz, \

John A. Lowell, [ of Class 11.

Benj. E. Cotting, )

George E. Ellis, \

Andrew P. Peabody, \ of Class III.

Charles C. Perkins, )

Rumford Committee. Morrill Wyman. James B. Francis.

WOLCOTT GiBBS. JOHN M. OrDWAY.

Edward C. Pickering. Stephen P. Ruggles. John Trowbridge.

Committee on Finance.

Charles Francis Adams, ) ^ . „ „ ) ex officio.

Edmund Quincy, ) *^

Thomas T. Bouve.

The following Committees were appointed on the nomina- tion of the President : —

Committee on Publication.

Alexander Agassiz. W. R. Goodwin.

John Trowbridge.

282 PROCEEDINGS OF THE AMERICAN ACADEMY

Committee on the Library.

Charles Deane. Henry P. Bowditch.

William R. Nichols.

Auditing Committee. Henry G. Denny. Robert W. Hooper.

Voted, To adjourn this meeting, at its close, to the second Wednesday in June.

Professor Watson presented a continuation of his paper on " Inland Navigation."

Six liiindred and ninety-tliird Meeting.

June 14, 1876. — Adjourned Annual Meeting.

The President in the chair.

The following papers were read : —

On parachlor and paraiodbenzjdbromides, by Professor C. L. Jackson.

On derivatives of parabronibenzylbromides, by C. L. Jack- son and Woodbury Lowery.

On methyluric acid, by Professor H. B. Hill.

On the salts of methyluric acid, by O. R. Jackson.

The following papers were presented by title : —

On the solubility of sodic and potassic bromides in absolute alcohol, by J. H. Bullard and A. L. Thomsen.

On the atomic weight of antimony, by Professor J. P. Cooke, Jr.

Contribution towards the history of the fluorides of man- ganese, by W. H. Melville.

Researches on the substituted benzyl compounds, by Pro- fessor C. L. Jackson.

On the effect of temperature on the viscosity of air, by S. W. Holman.

On the characters of a new genus of Papaveraceae, Canbya; also, of certain other new Californian species of plants, by Professor Asa Gray.

OF ARTS AND SCIENCES. 283

Six Imndred and ninety-fourth Meeting.

October 11, 1876. — Stated Meeting.

The President in the chair.

Letters were read from Messrs. Curtius, Le Due, Mignet, Pattison, Rawlinson, Stanley, Abbot, and Searle, accepting their election as members of the Academy ; also from Messrs. Bowen and Cabot resigning their membership.

Voted^ To place six hundred dollars ($600) of the income of the Rumford Fund at the disposal of the Rumford Com- mittee to aid Professor Langiey in his researches on radiant energy.

Professor A. G. Bell, by invitation presented a paper on telephony.

On the motion of IMr. Emerson it was

Voted, To heartily congratulate Professor Bell on his won- derful discovery in telephony.

The following papers were presented : —

On the use of glass circles for meridian instruments, by Mr. W. A. Rogers.

On the suspension of a ball in a jet of air having an incli- nation of 45° by Mr. W. A. Rogers.

On a new edition of Ptolemy's catalogue of stars, by Mr. C. S. Peirce.

Dr. Gray presented, by title, the following paper : —

Contributions to North American Botany.

Six hundred and ninety-fifth Meeting.

November 10, 1876. — Monthly Meeting.

The President in the chair.

The Corresponding Secretary announced the death of Nicholas St. John Green, William A. Stearns, and Edward Wigglesworth, Fellows of the Academy ; also of Charles Davies, Associate Fellow, and Christian Gottfried Ehrenberg, Foreign Honorary Member. He also read letters from Mon- sieur G. A. Him acknowledging the receipt of the Works of

284 PROCEEDINGS OP THE AMERICAN ACADEMY

Count Rumford, and from Dr. F. Garrigou, requesting the Academy to send him samples of the principal American thermal springs. This last was referred to the Smithsonian Institution.

Professor John Trowbridge, on behalf of Professor J. D. Whitney, presented a paper on the velocity of the shock of the Hell-Gate explosion.

Mr. W. A. Rogers exhibited a series of drawings of the planet Jupiter, by Mr. L. Trouvelot ; he also presented, by title, a paper, by Mr. L. Waldo, on the pitch of the screw of the micrometer of the equatorial of the Harvard College observatory.

Mr. S. P. Sharpies presented the following papers by title : —

On the aceto-arsenite of copper.

On some further determinations of standard milk.

Six hundred and ninety-sixth Meeting.

December 13, 1876. — Monthly Meeting.

The President in the chair.

The President read a letter from Mr. Alfred Tennyson, accepting his election as Foreign Honorary Member ; also, a letter from Mr. William Ferrel, resigning his fellowship.

The following papers were presented : —

O'n the structure of the chrysalis of butterflies, by Mr. S. H. Scudder.

On the two-point and three-point problem in surveying, by Professor E. C. Pickering.

On the water of the ponds of eastern Massachusetts, by Mr. S. P. Sharpies.

Six hundred and ninety-seventh Meeting.

January 10, 1877. — Stated Meeting.

The President in the chair.

The following papers were presented : —

On the micrometer level, by Professor E. C. Pickering.

OP ARTS AND SCIENCES. 285

On vortices, by Professor John Trowbridge.

On tri-iodo-resorcin, by A. J. H. Norton, presented by Pro- fessor E. N. Horsford.

On the mythology of the Noith American Indians, by Professor J. W. Powell.

The President announced the death of Professor Alexis Caswell, of Providence.

Voted, To adjourn this meeting, at its close, to the second Wednesday in February.

On the suggestion of Professor F. W. Putnam, it was

Voted, To refer to the Council the question of depositing a Mexican mask and a plate of Dighton Rock in the Peabody Museum of Archaeology.

Six hundred and ninety-eighth Meeting.

February 14, 1877. — Adjourned Stated Meeting.

The President in the chair.

Sir James Paget, of London, was elected a Foreign Hono- rary Member in Class II., Section 4, in place of the late Gabriel Andral.

On the motion of Professor Lovering, it was

Voted, That a committee of three be appointed to consider and report upon the expediency of memorializing Congress to pass a law making it the duty of postmasters to collect the facts in regard to accidents to life or property by lightning which may occur within the area covered by their departments, and communicate the same as may hereafter be designated.

A committee was appointed consisting of Messrs. Lovering, Bigelow, and Pickering.

Dr. Thomas M. Brewer read a paper on parasitic birds.

Professor A. Graham Bell, introduced by the Recording Secretary, presented a description of his further researches in telephony.

Dr. Williams, on the introduction of Dr. B. E. Cotting, read a paper on French verbs.

286 PKOCEEDINGS OF THE AMERICAN ACADEMY

Six liwnclred and ninety-ninth Meeting.

March 14, 1877. — Stated Meeting.

The President m the chair.

The President announced the death of Alexander Braun, Wilhehn Hofraeister, J. C. Poggendorff, and Karl Ernst Von Baer, Foreign Honorary Members; and of C. H. Davis, Charles Wilkes, and F. B. Meek, Associate Fellows.

The following gentlemen were elected members of the Academy : —

Alexander Graham Bell, of Salem, to be a Resident Fel- low in Class I., Section 3.

Jeremiah Lewis Diman, of Providence, to be an Associate Fellow in Class III., Section 3.

William Ferrel, of Washington, to be an Associate Fellow in Class I., Section 1.

The Treasurer read a letter from the Hon. E. B. Wash- burne, giving an account of the repairs which he had caused to be made at the expense of the Academy of the monument of Count Rumford at Paris.

The following papers were presented : —

A mathematical discussion of vortex rings in liquids, by Professor John Trowbridge.

Upon an application of Lane's law of the accumulation of solar heat, by Professor Benjamin Peirce.

On systematic errors in star declinations, by Professor E. C. Pickering.

Antigeny ; or, sexual dimorphism in butterflies, by Mr. S. H. Scudder.

On a new form of clock escapement, by Professor C. A. Young.

The following papers were presented by title : —

Theory of the horizontal photoheliograph, including its application to the determination of the solar parallax by means of transits of Venus, by Professor William Harkness.

On a base from the residues of aniline, by Professor C. L. Jackson.

OF ARTS AND SCIENCES. 287

On a method of measuriug electro-motive power by B. O. Peirce, Jr.

A note on tlie conduction of heat in a solid, by B. O. Peirce, Jr.

Seven hiindredtli Meeting.

April 11, 1877. — Monthly Meeting.

The President in the chair.

The Corresponding Secretary read letters from Messrs. Diman, Ferrel, and Paget, accepting their election into the Academy.

On the motion of the Treasurer it was

Voted, That the thanks of the Academy be presented to the Hon. E. B. Washburne and to Mr. Riggs for their services in connection with the repairs of the monument of Count Rumford in Paris.

The following papers were presented : —

On the haloid compounds of antimony, by Professor J. P. Cooke, Jr.

On the temperature of a perfect gas which is in convective equilibrium, by Professor Benjamin Peirce.

The following papers were presented by title : —

On parabrombenzyl compounds, by C. L. Jackson and Woodbury Lowery.

On furfurol formed in the dry distillation of wood at low temperatures, with a note on Scanlan's pyroxanthin, by Pro- fessor H. B. Hill.

On some new algse of the United States, by Professor W. G. Farlow.

Mode of germination in the genus Megarhiza, by Professor Asa Gray.

Seven hundred and first Meeting.

May 9th, 1877. — INIonthly Meeting.

The Vice-President in the chair.

Messrs. Cooke, Eliot, Agassiz, Ellis, and Perkins were ap- pointed a committee on nominations.

288 PROCEEDINGS OF THE AMERICAN ACADEMY.

The Recording Secretary declined to be regarded as a candidate for re-election.

The following papers were presented : —

On the iodides of antimony, by Professor J. P. Cooke, Jr.

On the chemical relations of pressure, by Professor T. S. Hunt.

On adiabatic surfaces, by Professor John Trowbridge.

On the preparation of nitrogen gas, by Professor Wolcott Gibbs.

On diamido-sulphobenzide-dicarbonic acid, by Arthur Michael and T. H. Norton, presented by E. N. Horsford.

On paraiodbenzyl compounds, by Professor C. L. Jackson and Mr. C. F. Mabery.

On some new algse new to the United States, by W. G. Farlow.

Descriptions of new species of plants with synopses of cer- tain genera, by Sereno Watson.

The following paper was presented by title : —

Characters of some new, or little known, genera of plants, by Professor Asa Gray.

The Corresponding Secretary presented the following annual Report of the Council : —

REPORT OF THE COUNCIL.

Since the last report, May 10, 1876, the Academy has lost by death fifteen members, as follows : four Fellows, Nicholas St. John Green, W. A. Stearns, Emory Washburn, and Edward Wigglesworth ; five Associate Fellows, Alexis Cas- well, Charles H. Davis, Charles Davies, Fielding B. Meek, and Charles Wilkes; six foreign Honorary Members, Braun, Ehrenberg, Hofmeister, Lassen, Poggendorff, and Von Baer.

NICHOLAS ST. JOHN GREEN.

Mr. Nicholas St, John Green, Professor at the Boston Law School, and formerly lecturer at the Harvard Law School, died at Cambridge, on the 8th of September last. Although his name was only beginning to be known to the public, yet, to the eyes of his asso- ciates, he occupied, at the time of his death, as important a position in the field of jurisjjrudence as did the equally lamented Chauncey Wright in that of philosophy ; and in the sudden deaths so near together of these intimate friends in the prime of life, the Academy has lost two of its most gifted members.

In the early practice of his profession, Mr. Green acquired a critical knowledge of the criminal law ; and he undoubtedly started with a superstitious respect for the technical element which still prevails in that part of the law. In fact, it would seem evident that, as a younger man, he must have held a good many of the prejudices, legal and polit- ical, which are natural to a strong nature unchastened by learning and reflection. But his reason was stronger even than his temperament ; and as time went on, and he became a student of history, political economy, psychology, and logic, prejudice gave way to philosophy, and his convictions, without losing in strength, were tempered by an appre- ciation of the other side which powerful men do not always acquire. VOL. XII. (y. s. IV.) 19

290 NICHOLAS ST. JOHN GREEN.

He handled a question of law not only with tlie mastery of a logician who easily reduced a case under established principles, but, also, and with equal jDOwer, in the light of the history which explains those principles, and the considerations of political science and human nat- ure which justify them. The evidence of his ability was not confined to the lecture-room ; for it is not too much to say, that no man at the Suffolk bar produced a greater effect upon the opinions of the Supreme Court, in the cases which he presented, than he. His arguments, in addition to the qualities of substance which we have mentioned, had a terseness and simple beauty of form which it is impossible to compare with any less-distinguished models than those of Judge Curtis. Mr. Green did not live long enough to construct a systematic work ; but as, with him, theory was not an excuse for ignorance of details, but was based aS much on exact and practical knowledge as it was on broad and careful study outside the law, those who knew him best hoped and expected that, when he was satisfied with his patient prep- aration, he would produce results worthy of his talents. A few notes to his two volumes of criminal cases, two or three articles in the " American Law Review," and three model volumes of reports, are all that the profession can judge him by; and they are, perhaps, enough. But those who have had the benefit of his conversation and criticism know that, although he had already justified the opinion of his friends, he gave promise of still greater achievements with which he might have enriched the world and honored his profession had he lived.

" He was such a philosopher as needs a Diogenes Laertius to por- tray him," writes, in a private letter, one who was familiar with his modes of thought. " The basis of his philosophy was, that every form of words that means any thing indicates some sensible fact on the exist- ence of which its truth depends. You can hardly call this a doctrine : it is rather an intellectual tendency. But it was Green's mission to insist upou it and to illustrate it. This was his guide, I feel sure, in the study of law. Witness his essay on the doctrine of responsibility. And he desired to apply the same principle to other branches of philos- ophy, — to Logic, to Psychology, &c. But these subjects he did not choose to follow out for himself into detail. He cared for them chiefly as fields to assert his ruling principle in : beyond that, he was more or less out of his province. He rather undervalued systems ; prizing more highly brochures which put some single principle in a strong li<i"ht. Bentham's refreshina: manner of searchinoj for realities, and contemptuously tossing aside formal doctrines of the law in rummag- ing down to the very pleasures and pains which result from different

WILLIAM AUGUSTUS STEARNS. 291

legal arrangements, greatly pleased him. But he did not much care for Bentham's systematic works : it was rather his horde of pamphlets, raiding like Cossacks into the legal realm, which delighted him. So, of political economists, he most admired Jean Baptiste Say, perhaps because he was a great pamphleteer.

" Green carried the same keen scent for sensible facts and contempt for every thing else into his affections and his tastes. He was a most warm-hearted man, with an abounding sympathy for all sorts of people, a great fondness for children, and a love for animals. He had also a fine taste for poetry, of which he had read a great deal. But one did not at first so much note his delicate ajipreciation of what was real, as his scorn for all that was unreal. He had a quality, which was cer- tainly not roughness, but which, for want of a better appellation, might be called a Socratic coarseness. It was well fitted to be the sturdy support of his realism, and gave one a positive pleasure when one knew him, as if it had been an artistic study. He had an over- flowing spirit of good-fellowship, and a Rabelaisian humor, without the Rabelaisian cynicism. I see him now, as he draws back from a game of whist, his genial nature shining through the merry twinkle of his eye. But, as he speaks, one perceives that it is not pure mirth that moves him, but sympathetic amusement ; for his talk is generally of some fine observation of human or animal nature. . . . He was wont to take up prostrate or hopeless causes with a zeal, unwise and Quix- otic from a worldly point of view, but which exemplified some of his highest traits."

o

WILLIAM AUGUSTUS STEARNS.

The Reverend Williasi Augustus Stearns, D.D., LL.D., President of Amherst College, died at Amherst, June 8, 1876, in the seventy-second year of his age. The genealogy of Dr. Stearns would add another proof, were such necessary, to the truth of the doctrine of the transmission of.moral and intellectual qualities, and even of tendencies towards particular pursuits, by hereditary descent. He came by the side both of his father and his mother of lon^ lines of Conorre^ational min- isters, devout and learned men, not inexperienced in the ways of mankind and the management of worldly business, from the part taken by the ministers of the old Congregational Establishment in the administra- tion of the affairs of their parishes and often of their parishioners. The Triennial Catalogue of Harvard College contains the names of graduates, nomina Uteris italicis exarata, scattered along the ranks of the eighteenth century and reaching back into those of the seven-

292 WILLIAM AUGUSTUS STEARNS.

teenth, througli whom Dr. Stearns traced his lineage. The earliest of all of his cis-Atlautic progenitors was of a time preceding the foundation of the College, — the Rev. John Woodbridge, who came to New England in the year 1634, and was the first minister of Andover in this State. Descended from ancestors educated in the best learning of their times, spending their lives in a profession which involved responsibilities, practical and secular, as well as moral and religious, it would have been strange if his mind and character had not had impressed upon them the qualities for which he was distinguished during his life. He was in a manner preordained to be a minister and the head of an insti- tution of learning from his birth.

The father of Dr. Stearns was the Rev. Samuel Stearns, who grad- uated at Cambridge in the year 1794, and his mother was the daughter of the Rev. Jonathan French, long the minister of Andover. Mr. French had begun his active life in the military service of the Prov- ince, and was Sergeant in the garrison which was maintained at the Castle in Boston harbor, when he was moved to exchange the sword of the flesh for that of the spirit ; and, after graduating in 1771, he was ordained minister of Andover as above. Mr. Stearns was settled over the town of Bedford, in this State, with a salary of three hundred and thirty-three dollars and thirty-three cents. The town further gratified him with a loan of a thousand dollars without interest, which probably enabled him to purchase a form of twenty acres to help in the support of his family. That some addition to his meagre stipend was convenient may be inferred from the fact that his children were thirteen in number, of whom eleven grew up to adult age. His farm he made a part of the physical education of his boys, and of their moral education as well, they assisting him, as they successively at- tained the proper age, in its cultivation, which he carried to a high degree of perfection. Notwithstanding the narrowness of his means, Mr. Stearns managed to send four of his five sons to Harvard, three of whom were ministers, and eminent in their profession. Of the sons, William, born March 17, 1805, was the second. He showed an early love of study and an extraordinary power of memory, some remarkable feats of which were remembered in the family ; such as his knowing the Assembly's Catechism perfectly at six years old, a curious example of purely verbal memory, as it was impossible that he should have at- tached any meaning to most of those doctrinal apophthegms at that childish age. A little later he learnt by heart the Gospel of Luke in one week in the intervals of his farm work and other occupations. A more chai'acteristic attempt of his was made on the outworks of good

WILLIAM AUGUSTUS STEARNS. 293

learning by getting surreptitious possession of the Latin grammar, — for the good minister's means admitted of but one for all his sons, — and secretly beginning the study of Latin by himself, an effort which proved to be quite beyond his boyish strength.

When young Stearns reached the age at which his brothers had been sent to Phillips Academy, in Andover, where his father also had had his school education, he naturally asked to be allowed to go thither in his turn. But his father, oppressed by the res angusta domi, replied, sadly, " My son, desirous as I am of doing what you ask, I do not see that Providence opens the door ! " "I do not iDelieve, sir," replied the boy, " that Providence will open it, unless you knock ! " Struck by the spirit or the good sense of the answer, the father knocked in faith: the door o^jened and remained open until the sou had passed through the school and afterwards throui2;h the college. It was a favorable time when the boy of fifteen took up his abode in that beautiful town, which Improvement had as yet spared, and where he spent three hajjpy and profitable years. The academy was then under the mas- tership of the excellent Principal, John Adams. The government of this gentleman differed from that of most masters of his time and before and since. His rule, though firm and decided, was gentle and kind. Corporal punishment was almost unknown, and inflicted only in cases of the grossest misconduct. He did not permit the principle of rivalship and emulation as motives of action. There was no head and no foot to classes, no medals or rewards of merit, no parts at the Annual Exhibition distinguishing degrees of scholarship. His pupils were expected to study because it was their duty and what they were at school to do. He thus saved them from the jealousies, heart-burnings, and disappointments which so cruelly wring the breasts of very young persons. At the more mature age of young men in college, the case may be different, and such contentions and prizes may be fitting prepara- tion for the conflicts of life. But for young children we are satisfied that Mr. Adams's philosophy is the wise and true one. His system justi- fied itself by its success. The scholarship of his pupils was quite equal to the best of his time. We believe that there was ne.ver an instance of one of his scholars failing at the examinations for admission to college, and in college they won their fair share of college distinc- tions. In his old age his Alma Mater, Yale College, gave him the degree of Doctor of Laws, an honor which she might have gracefully bestowed forty years sooner, when, besides being a compliment and a gratification, it would have been a professional advantage. For he was a most dutiful son of that mother of his mind, and always did what he

294 WILLIAM AUGUSTUS STEARNS.

2:)i'operly could to cletennine the steps of a questioning pupil in the direction of her academic shades.

Under these gentle and gracious influences, young Stearns spent three diligent years, and at the Commencement of 1823 he entered Harvard College to pass four other diligent years of studious prepara- tion for his vv,ork in life. From the first he took a high rank among his fellows. His preparation for the exercises of the class-room was always thorough to 2:)erfection, and his recitations accurate, elegant, and fluent, but without any studied attempt at disj^lay. Though not recluse, he was retired in his habits, and devoted himself earnestly to the work that he was there to do. Though his intimates were few, there was no man of his time more cordially esteemed and respected of all that knew him than he. The chief drawback on the happiness of his well-spent hours was the narrowness of his circumstances, which more than once threatened to cut short his colleire career. At the most critical moment, however, when he was brought face to face with this cruel necessity, he was relieved from his distress by the timely and judicious generosity of President Kirkland. By dint of keeping school in the winter vacations and of the most rigid economy he managed to win his way to the end, and he took his degree at the Commencement of 1827 with the third honor of his year. If his worthy master, Mr. Adams, had entertained any fears — which it is altogether probable that he did — that his promising pupil might be shaken in his faith in the strict theology of his fathers through the heretical influences to which he was subjected at Cambridge, he was happily disappointed ; for the young Bachelor of Arts issued from the furnace without the smell of fire upon his garments. Indeed, we imagine that it would have been necessary for him to court the flames to have had his gar- ments even singed by the fires of heresy. We believe that there was never the slightest attempt at proselytism made by the heresiarchs of the college. Even attendance on the theological lectures of Dr. Ware, which were necessarily imbued with Unitarian ideas, was not required of students who objected to their doctrine. However this may have been, Mr. Stearns remained faithful to the religious tenets he had imbibed in youth, in which he was assisted by a society of young men of Evangelical views, which met weekly for devotional purposes and to strengthen one another to hold fast to the faith as delivered to the Fathers.

After a year's interval of school-teaching, Mr. Stearns joined the Theological Seminary at Andover, and went through the regular course of three years. Having received his license to preach in 1831, and

WILLIAM AUGUSTUS STEARNS.

295

gone forth into the world to seek a fit field for his labors, he showed iu the choice of one his characteristic wisdom and moderation. He was ambitions rather of doing effective work iu his calling than of winning the high prizes of his profession. He preferred to build up the waste places rather than to enter into the rewards of other men's labors. Instead of continuing to preach as a candidate in the expecta- tion of securing one of the metropolitan parishes, which his learning, his character, and his gift of pulpit eloquence would almost certainly have procured for him, he cast iu his lot at once with a young and struggling congregation in Cambridgeport, which had little to offer him excepting an opportunity for work and friendly co-operation in it. His superiors in the profession, among them at least one of the pro- fessors at Andover, marvelled at his choice, and looked upon it as a throwing away of himself and his gifts and graces. And, indeed, Cam- bridgeport was not at that time the thriving and populous settlement that it has since become. There was little that was inviting to the eye or to the taste in the straggling streets and flat surroundings of that uninteresting suburb. Such as it was, however, there it was that Mr. Stearns set up the staff of his rest and entered upon what he had accepted as the business of his life. His neighborhood to Boston and Cambridge, it is very likely, was a consideration which may have had some weisfht in his decision. He began his ministerial life with a sal- ary of seven hundred dollars and a proportion of the pew-lettings, — a provision scarcely more ample, the difference in the value of money considered, than the humble stipend which was thought sufficient for the modest needs of his father at Bedford, nearly forty years before. Here Mr. Stearns remained for twenty-three years, beloved of his people, respected by his neighbors, and useful in various directions outside of his vocation. Besides being chairman of the School Com- mittee of the town, he was a member of the State Board of Education and an Overseer of Harvard University umler the charter as modified in 1810. The twenty-three years of the pastorate of Mr. Stearns were years of great success in his function. He built up his congrega- tion from the feeble beginnings of the commencement of his ministry to be one of the most prosperous and flourishing in the neighborhood of Boston. And he had provided for himself a convenient and pleas- ant home.

While thus happily situated and usefully employed, doing well what he loved best to do, Dr. Stearns — for his Alma Mater had given him the degree of Doctor in Divinity the year before — was invited in the year 1854 to assume the Presidency of Amherst College. The offer

296 WILLIAM AUGUSTUS STEARNS.

of so important a positiou was naturally gratifying to him as a testi- mony of the most eminent men in his denomination to their belief in his qualifications for such a post, but its consideration could not be entertained without a painful conflict of contending personal feelings and professional duties. The unwillingness of the congregation he had so successfully built up to part with him, and his own reluctance to leave a scene where he had done and enjoyed so much, for a new and untried field of labor, embarrassed the decision of a question so material to his future with many conflicting emotions and considera- tions. Happily for himself and the college, his deliberate judgment was in favor of the acceptance of the Presidency, and he entered upon its duties in November, 1854. If the governing authorities of the college had ever doubted Dr. Stearns's eminent qualifications for the wider field of activity they had opened to him, they very soon learned from his otficial conduct how wise and fortunate their choice had been. By nature, by education, and by experience of men, he was eminently fitted for the oversight and direction of an institution for the higher education of youth. Learned, and a lover of sound learning, standing by preference upon the ancient ways of academic teaching, but not stubbornly tenacious of them, he was ready to consider and accept the newer ideas and methods which European influences and the growing claims of the physical sciences are urging upon the educators of the day, to the degree and in the manner that seemed to him best adapted to the present condition of education in this country.

While he was thus at once wisely conservative and judiciously pro- gressive in his dealings with the more recent theories of academic instruction, his personal and official relations with the undergraduates were of the most kindly and paternal description. His native courtesy and winning suavity of manners won for him their afiection and confi- dence whenever they came into personal contact with him. His weight of character and sound judgment impressed them with a sense of his sagacity and wisdom in all his counsels and suggestions. His very presence bore the stamp of perfect uprightness and absolute truthful- ness. He held that to be the best government which governs the least, and his endeavor was to make his students a law unto them- selves and to teach them to rule their spirits and their lives by the laws of self-respect and right reason. But when discipline was needed to maintain the good order or the good reputation of the college, he could be as stern and severe as Justice herself. The transgressor found that his way was hard when he had incurred the just displeasure and judicial censure of the President. His heart's desire was to prevent misrule

WILLIAM AUGUSTUS STEARNS. 297

or disorder by his moral influence over the minds of his students, but yet so that they should understand it to be deliberate wisdom and not timid 23olicy that inspired his mild rule, and that the severities of dis- ci[)line were at hand for the vindication of the laws in the last resort. Personal instruction of the students in the class-rooms was not to his taste, and he had no special gift in this direction, and he largely left that office to those to whom nature or experience had made it easy. In planning, directing, and superintending the teaching of others, he found his more congenial and appropriate employment as the head of the college. In these duties, and especially in the exercise of the most important function of the president of a college, that of the selection of the instructors and officers who are to work under his supervision, he used his constitutional diligence and evinced that instinctive knowl- edge of men and that intuitive discernment of spirits which leads to the filling of the right places with the right men at the right time.

Besides the qualities at which we have glanced, which eminently fitted President Stearns for the headship of an institution of good learning, he had others which enabled him to do his college most ma- terial service. He had a natural turn for affairs and was an admirable man of business. Under his presidency, the funds of the college were very largely increased, the number of students and of teachers more than doubled. The college buildings are twice as many as at his accession to office. The departments of instruction have been enlarged and extended in every direction. While holding firmly to the sound orthodox faith that a knowledge of the ancient languages is the indis- pensable foundation of a truly liberal education, the departments of the modern languages and literatures, of theology, astronomy, the physical sciences, of history and philosophy, and of the science of gov- ernment, were all of them reinforced, and some of them established during his incumbency. The importance of the fine arts and an- tiquities as a part of education was first recognized in his time, and a museum established for the promotion of those elevating and refining pursuits. The long-neglected but most important study of hygiene and the physical education wliich belongs to it received under him the attention it deserves, and with excellent results in the improved health of the students. The marked advance which Amherst Colleore has made within the last quarter of a century and the high rank it holds among the academic institutions of the country may be said, without disparagement of his eminent predecessors, to be mainly owing to the zeal and labors of President Stearns. The interests of his own col- lege, however, did not absorb his attention, to the neglect of those of

298 WILLIAM AUGUSTUS STEAENS.

education elsewhere. He asfaiu served on the State Board of Educa- tion, and it was lie who first proposed the Annual Convention of Col- lege Presidents to compare and discuss opinions as to matters of interest common to them all.

When the civil war broke out, President Stearns was not slow to discern the needs and the duties of that hour of crisis. Though he calmed the first enthusiasm of his young men who wished to answer at once the first call of the country, yet as soon as the urgency of the case was manifest, and it was clear that an appeal to arms was inevi- table, he encouraged the enlistment of his students, and sent them to the field with his blessing and hearty God-speed. And he did not withhold the sacrifice of his own son when duty to his country called for it. His youngest son, Frazar A. Stearns, then an undergraduate, went to the front as Adjutant of the 21st Massachusetts Regiment. After a brief but brilliant term of service this gallant youth fell at the battle of Newbern on the l4th of March, 1862, in the twenty-second year of his age. His father met this cruel calamity in a true spirit of Christian patriotism. His loyalty to the Union was but strengthened and made more active after it was thus sealed by the blood of his son. He might have said with the old Duke of Ormond on losing his sou the P^arl of Ossory, "I would not exchange my dead son for the living son of any man in Europe ! " General Burnside gave one of tlie guns captured by the men under Adjutant Stearns's command to the Col- lege as an expression of his sense of the merit of the young officer and as a fitting monument to his memory. This household offering to his country gave force and touching energy to the patriotic words which the President never failed to utter in the hour of need. He never failed to enforce the Christian duty of citizens to do their part in the jDolitical as well as the military service of the nation in his Baccalaure- ate and other addresses to the youth who sat at his feet.

It will be seen, from this impez'fect sketch of the career and the char- acter of President Stearns, that he had been singularly fortunate and happy in his life. And he was equally happy and fortunate in his death. He certainly died at his post, if ever man did. He was con- ducting the college prayers on the morning of his death, when ari-ested by the illness of which he died before the sun went down. In the fulness of his powers, in the bosom of his family, with every consola- tion that religion, domestic affection, and friendship could afford, with little pain and no fear, his useful and honorable life came to a tran- quil and happy close. It was a true Euthanasia.

The natural endowments and literary attainments of President

WILLIAM AUGUSTUS STEAENS. 299

Stearns were of a high order. His sermons and occasional addresses, man , of which have been published, show great clearness of thought, accuracy of reasoning, force of illustration, and rhetorical skill. But he was even more distinguished as a ready debater and brilliant ex- tempore speaker. He had great quickness of thought and remarkable fluency and felicity of speech. It is related of him that, while yet at Cambridgeport, he was told while on his way to church of the de.tth of Daniel Webster. He at once laid aside the sermon he had prepared, and delivered an unpremeditated discourse upon the dead orator, which his hearers regarded as not inferior to any of the more elaborate efforts of the eminent men who followed him on the same theme. On another occasion, at a public meeting where Mr. Webster and Mr. Everett had swayed the audience with their words of i^ower, Mr. Stearns was called for after the crowd began to disperse, and he held them long in eager attention, not less earnest and enthusiastic than that commanded by the great speakers who had gone before him. The moral and personal qualities of President Stearns, however, were those that endeared him most to his friends and enabled him to do the excel- lent work that filled his days, and to win the success that crowned his life. His personal and moral courage was perfect. He feared noth- ing but doing wrong. His success in the various activities of his life was owing not so much to the preponderance of any one quality of his character as to the balance and proportion of them all. His soundness of judgment, his absolute integrity and perfect truthfulness, his unfail- ing common sense, all contributed to give him that weight of character which made his voice potential in all matters of practical or academ- ical detail. He was firm and persevering in matters about which he had deliberately made up his mind, and he generally carried his points ; but it was because they were points that ought to be carried. His nature was singularly rounded and complete. His demeanor was marked by a modest dignity which claimed what was due to himself, while giving to others all that was due to them. Courteous of speech, gentle and polished in manner, cheerful in conversation, thinking and speaking no evil, yet capable of sternest indignation at injustice, cru- elty, or meanness, President Stearns left to his academic children, to his friends, and to the world an example of a highly educiited, high- principled, high-bred Christian Gentleman.

300 EMORY WASHBURN.

EMORY WASHBURN.

Emory Washburn, Governor of Massachusetts, and Professor in the Harvard Law School, was born during the first year of the present century, amid the simple life of one of the hill towns in the interior of the Bay State. He received a collegiate education first at Dartmouth and afterwards at Williams Colleges, from which he graduated iu 1817 ; he studied law at the Law School of Harvard College, and entered upon the practice of his profession in his native town of Leicester. In a few years, he removed to Worcester, where for many years he possessed the confidence of the tribunals and the community, and had, perhaps, the largest practice in this, the central county of the State, at a bar always eminent for the character and ability of its members. He was sent to the Massachusetts House of Representatives both from Leicester and from Worcester ; and was subsequently elected to the State Senate, for Worcester County. Soon after he was appointed a judge of the Court of Common Pleas, an office which he held for four years ; and in 1853 he was elected Governor of the State. In 1854, the degree of Doctor of Laws was conferred on him by his Alma Mater, and also by Harvard College. During this period of active life, in addition to his arduous professional and official duties, he gave freely of his time and support to all the best interests of society.

From such a career, at the ripe age of fifty-six, he became a Professor in the Law School at Cambridge, and remained in that position for twenty years. To it he brought the fruit of a long and ho'iiorable life ; to it he brought also the character which had made that life so truly honored, besides that warmth of the most abounding personal sympathy, and that devotion to his work which seemed more the prompting of his nature than the command of duty. These twenty years were the crown and glory of his life. And when, a year ago, at the ripe age of seventy-six, he resigned his chair^ because he felt that it might better be filled by a younger man, his associates could discover no abatement of force in mind or body. And such an active nature could not remain idle or be spared from the public service. After an interval of fifty years since his first election, he was returned to the Legislature of his native State by his fellow-citizens of Cambridge, and there with all the vigor of a youth he entered upon the arduous duties of Chairman of the Judiciary Committee of the House. While full of activity in manifold ways, both in public official duties, in private life, and in numerous associations for the promotion of the best interests of society, and amid friends and home, he received the last summons, and, through a short

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illness, passed into the other life. Such is the outline of his career ; what work has he left behind him ?

The work of such a man and teacher it is difficult to trace. It has mingled with the characters and minds of his pupils. Words of sym- pathy and 'wisdom, fitly spoken, have turned the current of many a life from waste to blessing. It is the very presence of his life and character, rather than his intellectual processes, which influences those around such 'a man as Emory Washburn. Yet some things may be definitely said of the result.

In the school where the great work of his life was done, he was ever so free-hearted in giving his sympathy and counsel to all who, from year to year, needed or sought it ; his usefulness in this respect was so tran- scendent that, by universal consent, he is pronounced the best beloved of all the teachers that school has ever had. His devotion was not to the ideal entity of the Institution, whose being is to live through the cen- turies. That might secure the devotion of more poetic minds. His labor of love was with and for the young men who resorted to it, full of the mingled holies and fears that attend their entrance upon life, com- ing often from the res angusta domi to secure encouragement and aid in the new and brief home where he was always found a father and a friend. Among the teachers of that school who have gone to their rest were Ashmun and Story and Greenleaf and Parker and Sumner ; yet so well known to the living that the name of each is a biography. Of those yet living, his companions in instruction, we may not speak. They, with the thousands of his pupils, will concur in the inscription to his memory, that he was the best beloved of all the teachers of this school of the law.

But a more specific and definite work he has done for the country at large, for our English-speaking race, for its body of jurists, and the administration of justice. His instructions in the school were chiefly given in the most difficult department of the law, — that of real property; the most difficult to us, because it does not grow out of the convictions or practices, or needs of our age or of our institutions, alone. It comes to us from other ages, from other political and social organizations, from other ideas of right, from other views of the nature and obligations of property, and specially of landed property. Its system of rules is, therefore, comjxjsite and intricate ; and not always reasonable to our minds, or even useful to existing interests. The needs of the present, and a forecast of those of the future, are innovating ui^on it, changing it, not always wisely. A remedy for one evil often admits greater evils into such ,a system of

802 EMORY WASHBURN.

law. Most of the law of personal property, on the contrary, is the growth of modern times, suited to the wants of the present ; or, in fact, but an adoption into the law of the life of the age. Its ideas become action ; its action becomes the law. The law follows the fact ; becomes its transcript and record. Not so with our law of real property. Some law of real property is everywhere essential : decisions upon it following the ancient pi*ecedents, bending to the emergencies or legisla- tion of recent times, are issued in scores of volumes with every year. The labor which will carefully study and collate them all ; which will sever the essential from the incidental part of each of these decisions ; which will collect, in two or three volumes, the substance of all of them ; which will endeavor to mould them into a harmonious system, for the guidance and instruction of the profession, the courts, and the community, — such labor, indeed, requires, in the first instance, a most faithful conscience in him who has undertaken such a work. That faithful conscience Professor Washburn had ; that immense labor was conscientiously performed. And the result is contained in his work upon the " Law of Real Property," now in three volumes ; and in the supplementary work on " Easements and Servitudes." It is one of the most useful works on that subject, both for the bar and for the public; the most useful practical work upon this subject which exists in the En£;lish lansuaste. The faithfulness of its citations saves an amount of time for those engaged in the administration of justice, and for those whose interests are involved in such administration, which exceeds any estimate.

A more forcible and less conscientious hand might mould the mass into more symmetrical form. Professor Washburn's duty was not to make the law, but honestly to report it as others declared it to be. " Blackstone's Commentaries" were written for students. The clear and easy flow of their style is yet unexcelled among expositions of the law ; for the law deals not with the graceful sentiments of life. It has no eesthetic side. It is devoted to the stern demands of justice, and to practical interests. Professor Washburn's style in recording its decisions was, like that of most law-writei's, —

" Subdued " To tliat it works in, like the dyer's hand."

Professor Washburn's influence upon the young men who com- menced with him the manly study of the law, and who are yet as- cending the paths of life ; the great tribute, rather than debt, which he paid to his profession and to the cause of justice, which is the first inter-

EDWARD WIGGLESWORTH. 303

est of civilized society, — these are the works of his life. To the results of them uo limit can be easily assigned.

His friends (no one could know him, aud not call him friend) all recognize that these crowning works of his life had their origin in the governing elements of his character, — devotion to duty and good-will to man. In him, wisdom and charity in its largest sense were most completely blended. His life, moreover, was fully rounded and his work well done. As he often expressed the wish, he died before "his eye was dim or his natural force abated." Never to have known weari- ness during a life of nearly fourscore years, full of usefulness, honor, and domestic comfort, is as great a blessing as ever falls to the lot of man, and this blessing Judge Washburn fully enjoyed.

EDWARD WIGGLESWORTH.

Edward Wigglesworth, a Fellow of the Academy of Class IH., Section IV., died at his residence on Sunday, October 15, 1876, in this city, where he was born, January 14, 1804. He was in his seventy- third year.

His ancestral and family name connects him with individuals conspic- uous and honored in their several generations, from the first settlement of the country, for their characters and services in the various ranges of life. His first progenitor in this country was li^dward Wigglesworth, from Yorkshire, in old England, who, coming to Charlestown in this colony in the summer of 1638, removed in the autumn to New Haven, where he died, October 1, 1653. A stone in the Green in that place, marked with the initials " E. W.," was long supposed to designate the grave of Colonel Edward Whalley, a member of the High Court of Justice which condemned Charles I. ; but it is now reasonably believed to denote the grave of the first Edward Wigdeswoi'th. Among; the children whom he brought with him to this country was one, then nearly seven years, who, bearing the name of Michael Wigglesworth, won great distinction in this colony as divine, physician, and poet. Having been trained by the famous school-master, Ezekiel Cheever, whose service as a pedagogue in New England covered a period of nearly seventy years, Michael became, in 1647, one of the earliest of the students in Harvard College. Graduating in 1651, he became a tutor and a Fellow of the college, while preparing for the ministry. Having labored for a season in the instruction of the Indians at INIartha's Vineyard, he was ordained as pastor of the church in Ma'den, in this colony, in August, 1656. Here, after a long service, he died in office,

804 EDWARD WIGGLESWORTH.

June 10, 1705, Though he was noted for his skill and efficiency in the medical practice of those days, he could not explain the nature of the malady which made him for most of his life a sufferer from a mysterious form of invalidism which interrupted his professional work, and caused him to make a voyage to Bermuda. As the poet of his age and country, he was the author, among various other compositions, of that which, under the title of " The Day of Doom," was the classic for children and their parents for more than half a century in New England.

Edward, the youngest son of Michael Wigglesworth, was inaugu- rated in 1722 as the first divinity professor in Harvard College, where he had graduated, on the foundation of Thomas Hollis, Esq., of Lon- don. Dr. "Wigglesworth having held this office for more than forty years, was succeeded in it, in 1765, by his son, Dr. Edward Wiggles- worth, Jr., who, in 1791, had, as his successor in it, the Rev. Dr. David Tappan, who was a great-grandson of Rev. Michael Wiggles- worth, till 1803. Thus, for a period of eighty years, descendants in three generations from the old Maiden divine filled one of the places of highest influence and responsibility in this colony, province, and State of Massachusetts. The second Prof. Wigglesworth was one of the original Fellows of the Academy, at its incorporation. Papers con- tributed by him appear in the earlier volumes of the Memoirs. His calculations for the consti-uction of Life Tables were especially valued. Thomas Wigglesworth, a graduate of Harvard in 1793, who studied law, but afterwards, in wide commercial business, became one of the most honored and successful merchants of Boston, was the youngest son of the second Professor Wigglesworth. The subject of this Memoir was the oldest son of Thomas, by his wife, Jane Norton, a sister of that eminent Biblical scholar, Prof. Andrews Norton of Harvard College.

From his earliest childhood Edward Wiijglesworth manifested those fine traits and virtues of character, and that love of the jjrocesses of thought and the acquisition of learning, which were so marked in him through his whole life. Having been prepared for college by the Rev. Ebenezer Pemberton of Boston, he completed his course there in 1822, graduating with the highest honors of his class. He pursued the study of the law in the office of the late Judge William Prescott, having there, as fellow-students, the late Franklin Dexter, and the late Nathaniel I. Bowditch. Though he began the practice of the profes- sion, it did not prove to be congenial or attractive to him, and he abandoned it to enter his father's counting-room, to aid him in his mer- cantile aflTairs.

EDWARD WIGr.LESWORTH. 305

Those who at the time or in later years had a personal and intimate acquaintance witli Mr. Wigglesworth, and were thus appreciative of the his[h and ahnost morbid conscientiousness, and of tlie even excessive tenderness of sympathy and benevolence, which were so marked in his character, can answer only with an assenting smile when told that he was not, either as a lawyer or a merchant, an effective agent in the collection of even the most honest debts. When put upon such errands his frequent report was that the creditors seemed so much in need, or so reluctant to pay. that he shrank from using any urgency, and so came back empty. Still, he was of service to his father in his business affairs, though he never engaged in such interests with partners or by himself. He acquired sufficient practical knowledge for the care of a paternal estate, his share in which made him •affluent. Intellectual and scholarly culture, with the oversight and administration of a large number of charitable, benevolent, and humane societies, divided in about equal measure the whole half-century of Mr. Wigglesworth's mature life. He was a dil gent reader and student, and acquired a large amount of varied knowledge, which he aimed to have accurate and thorough. When, in 182;), that learned and laborious German scholar, Dr. Fiancis Lieber, who had become naturalized among us, undertook to translate, and to adapt to the uses of American readers, the volumi- nous Encyclopaedia puldished by Brockhaus, of Leipsic, under the title of " Allgemeine deutsche Real-p}ncykiopiedie (Conversations- Lexicon), " he found it necessary to have efficient helpers. The enter- prise was for its time, a very serious and important one, having been preceded in that form of literature here only by the republication of the Loudon edition of Dr. Rees' Cyclopaedia. Dr. Lieber was so for- tunate as to secure the ready and competent co-o|)eration of IMr. Wig- glesworth. as his foremost helper. In the preface to the work, in thirteen volumes, published under the title of the '' Encyclopfedia Americana," Dr. Lieber makes the following recognition of the aid which he had received: ''Above all, I ought to acknowled<ie the zeal- ous and al)Ie co-operation of my friend and associate, Mr. Wiggles- worth, who will not permit me here to express my obligations to him in such terms as my feelings would dictate. With him I shall be hapj)y to share whatever approbation the public may think the work shall deserve."

If Mr. Wigglesworth had been prompted to devote his years of easy leisure to the examination and exposition of sotne single subject in science or literature, that he might prove his claims as an author, he would undoubtedly have produced one or more works that would have

VOL. XII. (n. S. IV.) 20

o

06 EDWARD WIGGLESWORTH.

secured for him approval, reputation, and fame. Such productions from his pen as came into print are simply fragmentary, mostly in the form of brief sententious "Reflections," having the point and force of clear moralizing and cast into the compressed shape of proverbs. He had a sagacious discernment, a fertility of imagination, and a vivacity and sparkle of wit and humor, running with equal facility into ppose or verse, which, however, he indulged in fulness only in the fes- tive enjoyments of a large and happy family circle.

Intervals of impaired health, making journeys and travels in this coiHitry and in Europe occasionally necessary for restoration, and a genei'al susceptibility to some depressive moods, — no doubt aggravated by his constant and faithful service in agencies of ministration to the sorrows and ills of humanity, — seemed at times to cloud the spirit of Mr. Wigglesworth. His modesty, diffidence, and self-depreciation, his purity of heart, his gentleness of spirit, and the fulness and generosity of his benevolent sympatiiies, drew to him the most tender attachment of his family and his connections, and the profoundest respect and regard of the whole community in which he was known. His name, with a generous sum attached to it, appeared in answer to all such appeals as made necessary the announcement of subscriptions for the purpose of drawing others ; but there was no record, public or private, of his da ly alms or of the secret channels of his generosity. The reli- gious sentiment was deep and strong in him through life, and it was the most potent element in the training ami influence of his character.

For more than thirty j^ears, Mr. Wigglesworth gave of his means, his time, and his warm interest, most efficient service to that foremost of the benevolent institutions of this city, " the Massachusetts General Hospital ; " having been through the whole of this period a member of its corporation, as one of its trustees, or vice-president, or president. He was also an officer of the first and best administered of the now numer- ous corporations for similar purposes among us, " 1 he Provident Insti- tution for Savings in the Town of Boston." In the discharge of this responsible trust, he engaged with a constant and patient diligence and fidelity, examining investments and securities as if he were himself the guardian of the frugal savings of each of the depositors. He took en- tire charge of two of the City Districts of the Boston Provident Asso- ciation, and for years supported them from his own resources, making no draught whatever upon the funds of the Association. Most of the other numerous charitable institutions of the city, and very many of its literary and religious enterprises found in him a wise and just administrator, and a generous patron. There are many of his associ-

ALEXIS CASWELL. 307

ates in one or more of these multiplied fellowships who will long cher- ish in love and respect the memory of this upright, kind-hearted, and thoroughly good man, as he came with his modest presence to husiness meetings, sitting for the most part in silence, but ready always, when his word and opinion were needed, to utter them with a calm wisdom and a gentle earnestness.

ALEXIS CASWELL.

Ox the 8th of January, 1877, Rhode Island lost, by death, an accomplished man of science, and one of her best citizens. Alexis Caswell was born in Taunton, Mass., on the 29th of January, 1799. His ancestors, on the father's side, were prosperous farmers, and were among the earliest settlers of Taunton. Thomas Caswell, of the fifth generation preceding, came, according to tradition, from Somersetshire, England. His will was admitted to probate in 1697; only fifty-eight years after the incorporation of Taunton. The grandfather of Alexis married Zibiah White, who was the great-granddaughter of Peregrine "White, the first born of the Pilgrims in America on board the May- flower, November, 1 620. Alexis Caswell, after spending his early years upon the farm, was prepared for college at tlie Bristol Academy in Taunton. Little is known of hi-> chara-ter and attainments at this time ; but, if ihe child is fjither of tlie man, he must have been ami- able, docile, and full of a liiirh ambition. At the age of nineteen he entered Brown University, over which Dr. Messer then presided. His course in college was eminently successful; and, at his graduation, in 1822, he received the first honors.

From 1822 to 1827, he was connected with Columbian College, Washington. D. C, as tutor or professor of languages; at the same time studying theology under Dr. Staugiiton, the President. In the autumn of 1827, he went with Dr. Irah Chase (professor in the New- ton Theological Seminary from 1825 to 1843), to Halifax for the pur- pose of establishing the Granville Baptist Church in that place. His plans were changed, in consequence of an invitation which he receivcMl from the people to remain among them. He was ordained on the 7th of October, and settled over them as their pastor. Having preached to them acceptably for a year, he received an invitation from the first Baptist Church in Providence in the summer of 1828 to assist the Rev. S. Gano, tlie pastor of that church. He had been in Providence only a few weeks, when he was ai)pointed Professor of Mathematics and Natural Philosophy in Brown University. Witli the

308 ALEXIS CASWELL.

exception of the time wlien he visited Europe, in 18G0-61, he dis- charged the laborious duties of this office for thirty-five years, to the complete satisfaction of the government and the pupils of the institu- tion. Engaging in its instruction soon after Dr. VVayland's accession to the presidency, he was his strong support throughout an able and vigorous administration. In many respects, one was the fitting com- plement of the other, and respect and confidence were felt equally on each side. In 1840, while Dr. AVayland was absent in Europe, Pro- fessor Caswell discharged the duties of President ; and, dui'ing the last three years of President Wayland's otfii-ial term, Professor Caswell, under the title of Regent, relieved him from all tlie anxieties of disci- pline, bringing to this delicate duty qualities of mind and heart which secured good order without alienating the affection of the students.

When Dr. Caswell resigned his professorship in 1863, he was sixty- four years of age ; and had fairly earned the leisure and the retire- ment which are the reward and the luxury of old age. But he was still young in the best sense of the word; young in his feelings, in his habits of industry, in his intellectual faculties, in the good constitution which he had inherited fi-om his father (who died in 1851 at the advanced age of ninety-one), and young in his passion to serve his day and generation to the end. Accordingly, he engaged in active affairs with a vigor and success which younger men might well have envied. Kefreslied by five years, not of repose, but of a change in his intellec- tual diet, he again obeyed jhe voice of his Alma Mater, which called him, in 18G8, to the Presidency of Brown University ; Dr. Sears, his predecessor, having been summoned to an urgent and difficult service by the strong voice of patriotism and humanity. Although Dr. Cas- well had been moving for a few years outside of the University domain, his heart was always there. He knew, better probably than any one else, the wants, the resources, and the aims of the institution ; and, notwithstanding that he stood on the brink of threescore years and ten, he brouglit to his high position the vigor, the freshness, and the hope of youth. Among the various needs of the University which he pressed upon the attention of the corporation, in his anninil reports, was the establishment of an astronomical observatory, suffi- cient for the purposes of instruction if not of research.

Soon after leaving the office of president, in 1872, Dr. Caswell was elected into the Board of Trustees, and, in 1875, he was chosen a Fellow of the Corporation. In 1841, he received the degree of D.D., and, in 1865, that of LL.D. ; both from his own university. For nearly fifty years, he had been associated with it, either as student,

ALEXIS CASWELL. 309

teaclier, president, trustee, or fellow : and in each and all of the«e rela- tions he had reflected back all the honors which he had received as a favorite son. Earnest, devoted, and generous himself, he had the power and the disposition to enlist others, of larger means, in the same cause. None of its distinguished children has exceeded him, perhaps none has equalled him, in length of service and fidelity to its sacred

tl"US*S.

The special function and the liiirh deliiiht of Dr. Caswell were those of an educator. When lie began his profession of teacher, he shared the fate of his contemporaries in older and richer universities in a new country. He was responsible for all the instruction given in mathe- matics and natural philosophy ; in face, he alone represented the scien- tific side of the institution to which he was attached. Afterwards, a professor of chemistry, and at a much later period professors of natu- ral pliilosophy or mathematics, were associated with him; so that, in 1850, his own duties were restricted to astronomy, from 1851 to 1855 to mathematics and astronomy, and after 1855 to natural philosophy and astronomy. It could not be expected of any man who was required to scatter his energies over a variety of subjects, which in a well appointed university would tax the best efforts of half a dozen professors, that he should have much leisure or dispositioii for original investigation in one direction. It was enougii, and more than enough, for the most laborious and ambitious teacher tliat he should maintain a high standard of scholarship in the wide field which circumstances forced him to cultivate. Much has been written durino; the last few years in regard to the endowment of scientific research. But this is a luxury of which no one dreamed in Dr. Caswell's day ; and its strong- est advocates at the present time are not in agreement as to the best way of accomplishing the desirable result. Mr. Huxley may be cor- rect in Iiis opinion that a moderate amount of teaching will not check but stimulate the zeal of the original explorer. But no one will think that a mind, wearied by excessive teaching, distracted by a multiplicity of topics, and prevented from rising in his instruction to tiie Alpine heights of science by the dulness or indifference of the average stu- dent who despairs even of reaching the table-land, is a congenial soil for advancing human knowledge. Under such circumstances, one of two things must happen, — either the work of teaching will be neglected, or that of original research will be left to men more favorably placed.

It must not be inferred from these remarks that Dr. Caswell was contented to remain stationary. At no time, since his scientific life

310 ALEXIS CASWELL.

began, has it been an easy task even to keep in sight the few who are steadily advancing the outposts of science; and, of late, it is quite impossible without concentration. Dr. Caswell's predilection was for meteorology and astronomy. During the long period of twenty-eight aud'a half years (fi'om December, 1831, to May, 1860), he made, with few interruptions, a regular series of meteorological observations, at the same spot on College Hill, in Providence. These observations, precise as regards temperature and pressure, and including also much information on winds, clouds, moisture, rain, storms, the aurora, &c., have been published in detail in Volume XII. of the " Smithsonian Contributions to Knowledge," and fill 17'.* quarto pages.

In 18-')S, Dr. Caswell delivered four lectures on astronomy at the Smithsonian Institution in Washington. They were of the highest order of pojjular instruction, and, on that account, were thought by Professor Henry worthy of being peimanently preserved in his printed report for that year. Whatever may have been, or may still be, the conflict between science and theoh)gy, there is no conflict between science and religion ; least of all in Dr. Caswell's mind. He says in his introductory remarks : " The mechanism of the heavens, in proportion as we comprehend more and more of its vastness atid seem- ing complexity, bears witness to the enduiing order and harmony of the universe, and points with unerring certainty to the superintending agency of an intelligent and infinite Creator." And again : •' We spontaneously pay the tribute of our homage to all great achievements. But in no case is homage more just or more enduring than that which all cultivated minds pay to him who stands as the minister and inter- preter of Nature, and makes known to us her laws and her mysteries. Many such adorn the annals of astronomy."

Dr. Caswell joined the American Association for the Advancement of Science at its second meeting, which was held at Cand)ridge iu 1850. Although he made no formal contribution to its proceedings, he was a fi'equent attendant upon the annual meetings, took part in the discussions, and always gave dignity to its deliberations by his character and his words. In 1855, the Association had its ninth meeiing iu Providence; and the hospitable reception then given to it, and the hearty appreciation felt for its labors, were largely due to his influence. The members expressed their gratitude for this service by electing him as the vice-president for the next meeting, in Montreal, But the death of the President elect. Professor J. W. Bailey of West Point, called Dr. Caswell to the chair. At this large representation of the science of the Continent (the only meeting which has taken place

ALEXIS CASWELL.

311

outside of the limits of tlie United States), he sustained the credit of his country on a foreign soil, by his dignified presence and his manly eloquence, to the great .-at i.s faction of all liis associates. At such a time and in such a position, Dr. Caswell appeared to great advantage. By his dignity, his address, and his courtesy he was eminently qualified to he a j)residing officer; and he was gifted witli a fluency, a felicity, and a weight of speech which rose to tlie requirements of the occasion. At tiie next meeting of the Association in Baltimore, the president and vice-president elect were absent, and every hand was u|)lilted in favor of placing Dr. Caswell again in the chair. Having been called to pre- side over two of the most brilliant gatherings of this scientific body, he was ex|)ectetl to discharge the last duty of a retiring president by giving the address at Springfield. After showing that science had an intellec- tual value far transcending its practical use, he discussed the objects, the opportunities, and the hopes of science in America ; drawing his illus- trations chiefly from astronomy, partly because it was his fiivorite study, and partly because it had the start of all others in material resources. In this excellent address, admirable in thought, spirit, and stvle. Dr. Caswell reiterates his conviction that genuine science is not unfriendly to religion. " We participate in no such fear. We wish explicitly to exonerate this Association from all suspicion of undermin- ino', or in any manner weakening, the foundations of that faith which an apostle says was once delivered to the saints. We cannot admit the opinion that any progress in science will ever operate to the disparage- ment of that de\out homage which we all owe to llim in whose hand our breath is. and whose are all our ways. Science, on the contrary, lends its sanction and adds the weight of its authority to the sublime teachings of revelation."

In this connection, two other scientific publications of Dr. Caswell may be mentioned: I. On Zinc as a covering for building; "American Journal of Science," 1^37. II. Review of ISichol's Architecture of the Heavens; "Chri.-tian Review," 1841. Dr. Caswell was elected an Associate Fellow of this Academy in 1850. He was one of the original members of the ^National Academy of Sciences. He wrote a Memoir of that worthy pioneer in American Science, Benjamin Silli- man, which has been printed in one of its volumes of Proceedings.

In this retrospect of the life and labors of Dr. Caswell, he has been seen almost exclusively in his professional relations, as the student and teacher of science. And here his mind took more delight in ranging over a wide field than in dissecting some single flower or tracing the path of a solitary molecule, although that may be a microcosm in

312 ALEXIS CASWELL.

itself. lie could not have become one of Berkeley's minute philoso- phers. He was no specialist, though he was never superficial. If he was not himself an original discoverer, he understood and admired the discoveries of others, and led others to do likewise. At one time he taught Butler's Analogy at the university, and with as fresh an euthu- siasm as if that alone had been the chosen work of liis life. And wherever there was a gap in the means of instruction, he was the per- son thounht to be fitted to fill it. His whole nature revolted at the suggestion of becoming a bookworm or a secluded student. He was emphatically a man of the world, though not of it. He was inter- ested in trade, manufactures, and finance. He was a good citizen, and took an active part in promoting the industrial, intellectual, and moi'al welfare of his city, his State, and the whole country. His sympatliies were deep and generous. Always welcomed in the cir- cles of the refined and educated, he will be no less missed in the homes of the poor and the unfortunate. His heart and mind and strength were liberally expended in the administration of the public charities of the city and State.

Dr. Caswell was an earnest spe^aker, ami a clear, warm, and vigorous writer. To his public^itions, ah'eady mentioned, may be added : I. <h B K oration in 1835. II. Review of Whewell's Bridgewater Treatise; "Christian Review," 1836. HI. Article on P^mulatiou ; "North American Review," 1836. IV. Address at the funeral of Rev. J. N. Granger, 1857. V. Memoir of John Barstow. VI. Ser- mon on the Life and Christian work of Dr. Francis Wayland.

Truly was it said of Dr. Caswell, at his funeral, that nature did much for him, but that grace had done even more. Firm and earnest in his own religious convictions, inflexible in his own peculiar theology, he had no taint of illiberality in his intellect or his heart ; ever abound- ing in that Christian charity which thinketh no evil of any who con- scientiously worshipped the same God from a different altar. He had mingled in the affaii-s of practical life more than usually happens to an academic career, but the purity, the integrity, ami the simplicity of his character were superior to its surroundings ; and, to the end, he seemed as much in place in the pulpit as if he had never left the pro- fession of his early choice. There was no austerity in his goodness ; hence it attracted those who could not have been driven. Sweet iu temper, cheerful in disposition, gentle, affectionate, affable, hospitable, he was happy in his life, and even more happy in his death. After his long day, in wliicli he had not labored in vain, his sun went suddenly down iu a cloudless sky. And behold the end of such a man : it is all

CHARLES HENRY DAVIS. 313

honor, and affection, and peace. The press, the university, the church, and the State, have borne witness to the excellence of his character and the usefuhiess of his life.

CHARLES HENRY DAVIS.

Charles Henry Davis was born in Boston, 16th January, 1807. His father was the Hon. Daniel Davis, a lawyer of distinction, and lonsr the Solicitor-General of Massachusetts. His mother was born Margaret Freeman, sister to the Rev. James F'reeman, the eminent mini!«ter of the King's Chapel. He was admitted to Harvard College in 1821 ; but left it two years later, to enter the naval profession. In 1841, however, the university conferred on him the degrees of A.B. and A.M., and, in 18()8, that of LL.D., and his name stands iu the triennial catalosue iu the list of members of the class of 1825.

His commission as midshipman bore date 12th August, 1823. For some fifteen or twenty years after this time, his life was occupied with the duties and pleasures of his profession. He became passed midship- man iu 1829, and lieutenant in 1834. His ever distinct personality outwardly displayed itself chiefly in the gayety, the spirit, and the physical energy of youth. But the activity of nature which thus found its expression was iu reality the outgrowth of the vigor and brilliancy of his mind and character; and these qualities were all the time gaining maturity and tempered strength in reading, reflection, and intercourse with the world. His habits of thou<iht and feeling bore ever after deep and pleasant traces of the education of those earlier years.

About 1840, Lieutenant Davis took up his residence in Cambridge, and undertook a serious course of reading and study, especially in mathematics, which he pursued under the guidance of Professor Peirce. In 1842, he was ordered to duty on the Coast Survey, of which Professor Bache was the next year appointed superintendent; and he continued as one of the most valued officers in this service till 1849. The department to which he was primarily assigned was the investigation of the velocity and directitm of the tides and currents in New York Harbor, in the Gulf Stream, and in the neighborhood of Kantucket ; and the efficiency and ability which he displayed in this work led to his frequent appointment on commissions, both then and subsequently, tx) examine the principal harbors of the country. These researches engaged him in the genei'al study of the laws of tidal action, in which he made valuable additions to knowledge, and was led to the adoption of new and striking views, embodied in his " Memoir upon

314 CHARLES HENRY DAVIS.

the Geolo"-ical Action of the Tidal and other Currents of the Ocean " (Mem. Am. Acad., new series, vol. iv.) and his " Law of Deposit of the Flood Tide" (Smithsonian Contributions, vol. iii.). The object of these publications, which made him known to men of science as an hydrogr;ipher of the highest learning and skill, was to exhibit the law of connection between ilie currents of tlie st^a and the alluvial deposits on its borders and in its depths, and to show tliat this law had con- tributed in past ages, in an important degiee, and was still constantly contributing, to the determination and modification of the forms of the continents.

At tiie same time with the performance of this valuable scientific work, he was rendering conspicuous services to the country, by labors of more directly practical utility. His discovery, in the successive years from 184G to 1S49, of a series of important shoals, before utterly un- suspected, lying in one of the most constantly traversed regions of the ocean, directly in the track of vessels sailing between New York and Europe, or between Boston and West Indian or Southern ports, attracted public attention very powerfully to the value of the Coast Survey, which had not then acquired the position it now holds in the confidence of the country. Several considerable wrecks and accidents, before unexplained, were accounted for by tiiese discoveries, which called forth special letters of acknowledgment from merchants and insurance companies.

Lieutenant Davis was detached from the Coast Survey in 1849, and ordered to duty as the first superintendent of the new "American Ephemeris and Nautical Almanac," which owed its foundation directly to his efforts. The following extract from a letter of Professor Bache to the Secretary of the Treasury, dated 17th July, 1849, — a letter in no way called for by any courtesy of custom, — shows the estimation in which he was held by his eminent chief: " The official reports of the progress of the Coast Survey have, from time to time, brought the name and services of Lieutenant Davis very prominently before the department, as marked by all the (jualities which insure distinction in such a work. The loss of his services will be deeply felt. The zeal, industry, knowledge, and judgment ripened by experience, which he has brought to the survey, cannot soon be replaced. They have conferred upon it some of its most decided claims to usefulness and public approval. In parting with this most valued officer for a field of duty alike honorable to him and useful to the country, I desire to place on the records of the Treasury Department the strongest expression of my sense of his merits in the career which he leaves."

CHARLES HENRY DAVIS. 315

But while the labors of our deceased associate in the hydrographic work of the Coast Survey establisiied his reputation as an accomplished and able investigator, and were of high public value, he rendered still more important benefits to his country and to science by his successful organization and conduct of tlie '• American Ephemeris." Tlie establish- ment of this work was urged by its projectors, and especially by Lieu- tenant Davis (the prime mover in the undertaking), wiih two motives: first, to advance the scientific character and standing of the country, by a publication of the highest order fiom a scientific point of view ; and, secondly, to promote the cause of astronomy itself, and render substan- tial services to navigation, by producing a work on a higher plane tiian the '• British Nautical Almanac," fully conformed to the latest develop- ments of knowledge, and likely to give an additional stimulus to pure research. To carry out this ambitious plan, with the revision of the solar, lunar, and planetary tables, and of various points of astronomi- cal theory, which it involved, it was necessary to eidist iu the work the ablest mathematical astronomers of the country, and at the same time to train up a body of young computers, and to inspire them not only with the spirit of numerical accuracy, but with the tiiie love of science and desire to advance it. To this arduous but most interesting task, Davis brought his admirable judgment and his fine scientific talents, together with that fortunate temperament which easily united various men in loyalty to one enterprise, and that generosity of nature which thought only of doing the work in the best manner, and gladly gave the freest possible play to others' individuality. The first volume of the " E^pliemeris " appeared in 1852, and was very favorably received on both sides of the Atlantic ; and it may be safely said, that, except the Coast Survey, of which the vast scope of course gives it pre-emi- nence, uo scientific work which has been carried on in this country has redounded more largely to the national credit. " The policy adopted in the newly formed office," writes one who was familiar with it, and whose judgment is authoritative, " tliough not in all respects to be per- manently imitated as a piece of administrative machinery, was such as to make it a more efficient promoter of mathematical astronomy in this country than any organization we have ever had. Young men of talent were looked for from all quarters, were employed without regard to personal or political influence, were paid according to their efficiency, and were encouraged to engage in any branch of mathematical or astronomical research which would tend to improve the almanac. In the work of th« office there was a freedom from discij)line ami restraint, which, though it might work badly under other circumstances, was

316 CHARLES HENRY DAVIS.

very favorable to the development of a school of mathematicians. Besides men like Peiice and Walker, who had attained eminence before becoming connected with his office, the names of President Runkle, Professors VVinlock and Newcorab, Chauncey Wright, and William P"'errel, may be cited as representatives of the men who were first brouirht out throu";h their connection with the Nautical Almanac."

In 1854, Davis attained the rank of commander; and, in 1857, he published an English translation of Gauss's "Theoria Motils Corporum Ccelestium." The period of his superintendency of the almanac was interrupted by a three years' cruise in the Pacific Ocean. This cruise was signalized by a striking exhibition of the decision of character and willingness to assume responsibility for which he was ever noted in the service, in his acceptance, in the name of the United States, of the surrender of Walker in Nicaragua, — a step which saved many lives, and prevented serious complications, and which Davis took with- out any explicit instructions from the commander-in-chief of the squadron.

In 1861, soon after the outbreak of the civil war, Davis was made a member of a board of officers assembled at Washington to inquire into and report upon the condition of the Southern coast, with a view to oifeusive operations on the part of the United States. This inquiry led to the organization of the squadron which was placed under the command of Flag-Officer Du[)ont, and of which Davis was appointed fleet-captain and chief-of-staff, and to the capture of Port Royal, — the first brilliant naval achievement of the war. Davis was prominently engaged in both the planning and the execution of this magnificent action ; in which two strong forts, splendidly manned, and mounting forty-three guns, nearly all of heavy calibre, yielded in four hours to an attack as beautiful as it was able, and one of the largest and noblest harbors of the South, — indeed, one of the finest in the world, — with all the surrounding country, fell into the hands of the Federal Government. In Flag-Officer Dupont's official report of 11th November, 1861, he says of Commander Davis : " In the organiza- tion of our large fleet before sailing, and in the preparation and system- atic arrangement of the details of our contemplateil work, — in short, in all the duties pertaining to the flag-officer, — I received his most valuable assistance. He possesses the rare quality of being a man of science and a practical officer, keeping the love of science subordinate to the regular duties of his profession. During the action, he watched over the movements of the fleet, kept the official minutes, and evinced

CHARLES HENRY DAVIS. 317

that calmness in dan;i;er, which, to my knowledge for thirty years, has been a conspicuous trait in his character."

In May, 1862, Davis (now captain) was appointed flag-officer of the Mississippi flotilla off Fort Pillow ; and, one or two days after assuming command, he with seven vessels beat off a squadron of eight iron-clads which had steamed up the river and attacked him. The action was a spirited one, and lasted nearly an hour. Three of the hostile gunboats were disabled, but avoided capture by taking refuge under the guns of the fort. On the 5th of June Fort Pillow was abandoned by the Confederates, and on the sixth Davis fell in with their ironclads and rams, opposite Memphis. A rimning flght ensued, resulting in the capture or destruction of all the Confederate vessels but one, and the surrender of IMeraphis. Davis then joined Farragut, and was engaged in various opei-ations near Vicksburg, and in the Yazoo River.

In this year, the Bureau of Navigation was established, and Davis was appointed its first chief. In 186"}, he received tlie thanks of Con- gress,— a distinction which entitled him to ten years of active service beyond the regular time of retirement, — and was promoted to the rank of rear-admiral. Two years later, he became superintendent of the Naval Observatory at Washington. In 186G, in compliance with a resolution of the Senate, he prepared a valuable '' Ueport on Inter- oceanic Railroads and Canals," which was revised and reprinted in 1870, and furnished by the Navy Department to Captain Selfridge for his instruction in making his surveys. In 1867, he was again ordered to sea, in command of the South Atlantic Squadron cruising in South American waters.

In 1868, while Admiral Davis was in command of this squadron, he became the object of a bitter personal attack, in consequence of his not acceding to the views of the United States Ministers in Paraguay and Brazil as to his proper action in relation to the troubles then agi- tating the former country. Into matters of controversy this is not the place to enter; but our notice would be incomplete without a brief recital of the facts of the case. A state of war existed in Paracruay, then subject to the dictatorship of Lopez ; and our minister, deeming his position insecure, withdrew from the country, leaving behind him two citizens of the United States, who were arrested and imprisoned, at the moment of his departure, on the charge of conspiracy against the Para- guayan government. Admiral Davis was accused of delay in demanding the release of these prisoners, and of accepting their surrender, when it ■was made, after a parley with Lopez and under conditious. In fact, the

818 CHARLES HENRY DAVIS.

charpje of delay arose from his declining to consider his squadron as under the orders of tiie diplomatic authorities : he acted with as much prompt- itude as lie conceived to be consistent with his duty of making sure of his ground in a much-debated case ; and the men were given up on a peremptory summons, accompanied by a proper display of force, and under no conditions. His line of conduct was thus completely success- ful ; and it was fully sustained by the State and Navy Departments. But a vote of censure was passed by the House of Representatives, under the influence of the hostility which had been excited in certain quarters by his independent course. The moral weight to be attached to this vote may be estimated from the circumstance, that it joined in the same condemnation Admiral Godon. whose action had been dictated by the explicit orders of tlie Secretary of the Navy. His reputation suffered nothing among those who fully understood the merits of the case. The affair was, in truth, a conspicuous instance of the decision of character, the soundness and reasonableness of judgment, the con- scientious and noble-minded patriotism, and the high sense of professional res|)onsiliility, which always distinguished him.

Admii'al Uavis returned from his South American cruise in 1809, and was for several years in command of the Navy Yard at Norfolk. In the winter of 187o-74, he was again appointed to the superintend- ency of the Naval Observatory, in time to take an active part in com- pleting the preparations for the expedition to observe the transit of Venus. Tn the session of 1874-75, Congress made an a|)pro|)riation for printing illustrations of the results of the Polaris Expedition to the Arctic regions, commanded by the late Captain C, F. Hall. The Secretary of the Navy requested Admiral Davis to prepare the work and take charge of its publication ; and this labor formed the principal occupation of the last two years of his life. He threw into it an interest which seemed to deepen at last witii every chapter; giving assiduous attention to the least details of the narrative, and l)ringing to bear on it all the additional illustrations he could anywliere gather of the character and purposes of the conmiander and other officers of the expedition. The work, which was nearly completed under his hand, is early expected ; and it is believed that it will be found fully worthy of its connection with his name.

For several years his health has somewhat declined. But he worked re<.'ula'-ly on the proofs of the Polaris narrative till the fourth day before his death, when he had to abandon the effort and go to bed. From that time he tailed very rapidly, but without sulfering, and died early in the morning of Sunday, 18th February, lb77.

CHARLES HENRY DAVIS. 319

" Notwithstanding the active and prominent hfe wliich Admiral Davis led, and his energy and dash as a naval commander," siiys one w^hose words have been already cited, "his tastes, especially in his later years, were much more those of the reiined gentleman of literary leisure than of the active man of the world. He was little inclined to mingle in general society, but rather sought that of the cultivated few whose tastes were congenial with his own. His relations with the men of science who were liis olHcial subordinates were singularly free from those complaints, jealousies, and distrusts which so often arise when military men are placed iu charge of works of a purely scientific character. This arose from an entire absence of every trace of jeal- ousy in his nature, combined with an admiration of intellectual supe- riority in others, which led him to concede every thing to it. He combined independence of cliaracter with Christian courtesy, in a way that made him a model to the young men by whom lie was surrounded. No human being who ever came into his presence was too lowly to be addressed with the most kindly courtes}' ; and, when arroganct- or im- pertinence became insufferable, no respect for position or influence gloved the hand which dealt the blow."

" His conversation was forcible, full of good sense, and most amus- ing," says another writer. " He brought to bear on any subject he took up a host of argument, illustration, and elucidation ; and he liked to brighten up the dryest discussion of professional and scientiflc mat- ters \\ith his original and vivid turns of expression, or with some apt and unhackneyed quotation. . . . He was an admirable officer. He had the true spirit of command, — strong, dignified, and quiet ; and one that, not needing artificial support, was accom[)anied by a thoroughly friendly relation to liis officers and mt^n. . . . But that which is felt most det'ply now by those who knew Admiral Davis well is the loss of a man of rare and noble character. He was a charming companion, abounding to the last in a natural freshness and gayety of spirit ; and he hud one of the most honorable, upright, true, generous, and gentle hearts that ever beat. He was a man of marked cournge, and had, eminently, the courage of his convictions. At the same time, he was distinguislied by perfect courtesy, having but one standard of manners — and that a finished, but unaffected standard — for all classes of men. . . . He bore good-will to every one, and was always in a cor- dial vein. Meanness, trickery, and malice, indeed, roused his bitter contempt. But a salient characteristic of at least his later years was his profound trust in human nature, his complete freedom from cyni-

320 CHARLES DA VIES.

cism, and his faith in the power of right anrl truth to conquer both the world and the individual conscience. He

" ' Still in his right hand carried gentle peace To silence envious tongues.'

. . . We may say of him, as it was said of Sir Launcelot, he was ' the kindest man that ever struck with sword.' "

CHARLES DA VIES.

On the 18th of September died Professor Charles Davies, of Fishkill, on the Hudson. His family was of VVcL-h origin, settled in Washington, Litchfield County, Connecticut. Born in 1797, he was removed with his father and his family to St. Lawrence County, New York, in the early part of this century. That region was then almost a wilderness, on the northern frontier. There he was a farmer's boy, inured to work, to country habits, and to some measure of hardship. With a strong constitution, quick mind, and impulsive character, he had all the elements which were necessary to sustain those habits of study and labor which made him a successful stuient and a most useful teacher. Li December, 1813, he was appointed a Cadet at West Point. In consequence of the rapid promotions (it then being war time), he was promoted Second Lieutenant of Artillery in December, 1815. He was only one year in the army proper, except being paymaster at West Point from 1841 to 184G. In December, 1816, he was appointed As- sistant Professor of Mathematics at the Military Acailemy, — a civil officer, created by law for the purpose of having permanent teachers. In 1821, he was appointed Assistant Professor of Natural and Experi- mental Philosophy; and in May, 1823, Professor of Mathematics. In this chair he remained until May, 1837, when he resigned, and removed to Hartford, Connecticut, chiefly with a view of preparing and pub- lishing the series of educational works which have since made him so well known. The offi.-e of teacher had, however, become habitual and natural to him. He loved it, and so he continued in it almost to the last years of his life. From 1839 to 1841, he was Professor of Mathematics in Trinity College, Hartford. Removing to West Point as paymaster, and subsequently to Fishkill on the Hudson, he was appointed Professor of Mathematics and Philosophy in the University of New York, in 1848, and Professor of the Higher Mathematics in Columbia College, New York, in 1857. There he remained until 1865, when he retired, and was elected Emeritus Professor. Even then he did not cease wholly his connection with teachers and teach-

FIELDING BRADFORD MEEK. 321

ing. He was invited to and often attended the Teachers' Associations and meetings throughout the country. In 1844, he was President of the Teachers' Association of New York ; and in recent years, a mem- ber of the "• University Convocation " of New York. It was to that body that he made his Report on the " Metric System," which was published in 1870. In 1824, the degree of A.M. was conferred by tlie College of New Jersey (Princeton) ; and in 1825, the same degree, by Williams College, Massachusetts; and in 1840, the degree of LL.D., by Geneva College, New York. If his was a life of actual teaching, it was perhaps still more so as the writer of text-books, and the author of methods. He began with the translation of Legendre's Geometry. It was a capital book on that subject ; and its success induced him to go on with other works. Among them are no less than six different grades of Arithmetics ; Elementary works on Algebra, Geometry, Trigonometry, Practical Mathematics, Surveying and Navigation, Analytical Geometry, Differential and Integral Calculus, Descriptive Geometry, Shades, Shadows and Perspective. In addition to these, he wrote the Logic and Utility of Mathematics ; and, jointly with Profes- sor Peck, the Mathematical Dictionary. The following is a complete list : Primary Arithmetic, Intellectual Arithmetic, First Lessons in Arithmetic, Elements of Written Arithmetic, Old School Arithmetic, School Arithmetic, Practical Arithmetic, University Arithmetic, Ele- mentary Algebra, New Elementary Algebra, University Algebra, Bourdon's Algebra, Elements of Geometry and Trigonometry, Legen- dre's Geometry, Practical Mathematics and Mensuration, Elements of Surveying, Elements of Calculus, Analytical Geometry and Calculus, Desfriptive Geometry, Shades, Shadows and Perspective, Foundations of Mathematical Science, Grammar of Arithmetic, Outlines of Mathe- matics, Mathematical Tables, The Metric System, Logic and Utility of Mathematics, Mathematical Dictionary.

FIELDING BRADFORD MEEK.

Fielding Bradford Meek was born in Madison, Ind., on Dec. 10, 1817, and died in Washington on Dec. 21, 1876. The circumstances of his little-eventful life are of small intere>t to his fellow-workers in science, save in so far as they show the conditions under which his pe- culiarly acute perceptions and admirable judgment became fitted for his excellent scientific work. Born in a community where science had no place, and urged by his surroundings to begin commercial ventures in a frontier society, with little preliminary training of any sort, and

VOL. XII. (n. S. IV.) 21

822 FIELDING BRADFORD MEEK.

with seemingly no inherited instincts leading towards a scientific career, we yet find him, after one or two unfortunate essays in business, which deprived him of a small patrimony, taking to the study of nature as by an instinct. Such inquiries as the writer of this notice has been able to make of his lamented fellow-worker, in their infrequent meetings, and of his narrow circle of early intimate friends, have failed to show in any clear way the steps which led to his beginnings in science. Much is, perhaps, to be attributed to the fact that his birthplace and the scene of his last work was in the midst of a region richly stored with fossil remains of an extinct and peculiar life ; remains that are so captivating in their very strangeness that they cannot fail to gain the attention of eyes not sealed to the great problems of the earth. His body, naturally weak, — for he inherited a malady of the lungs that made his life a long struggle with disease, — may have helped him to that isolation of interests which readily drives a mind of acute percep- tions into studious ways.

It is no part of the purpose of this notice to consider his altogether admirable personal life, — that must be left to other and fitter hands ; but there is yet another circumstance of his labor which will interest all those who are concerned with the question of the circumstances that have surrounded those who have done great work in science : for the greater part of his life, our late comrade was cut off by almost total deafness from all ready contact with the world ; for all the later and most studious years he was absolutely deaf to every sound. Yet it should be told, as a part of his excellence, that this imprisonment within himself never lessened his beautiful kindliness of spirit, nor checked his ready sympathy with the life about him.

It is Mr. Meek's paheontological labors which will remain his fittest claim to the gratitude of scientific men. Extending, as they do, over a long term of years, and concerning materials from all parts of the geo- logical section, it is difficult to give them any general characterization. To them all may be given the highest praise for painstaking labor and perfect honesty of purpose. They nearly all belong to that class of works which are done in the interests of historical geology, ratlier than of biology. In this method in which his work was done, he but fol- lowed the necessary course of all those who take part in the great work of exploring a region unknown to science, describing facts as they are successively ascertained without much reference to general conclusions. His palajontological work was begun in connection with the surveys of Dr. David Daleman iu Iowa, Minnesota, and Wisconsin, in 1848. After the close of these labors, he remained unconnected with any

ADMIRAL CHARLES WILKES. 323

public work until 1852, when he became an assistant of Mr. James Wall in his great palfeontological explorations of New York. From this time to his death he was steadily occupied in that class of govern- mental researches that forms so large a part of our American scientific work. In the palseontological studies of the surveys in New York, Missouri, Illinois, and Ohio, he had a large share ; and in all of them has raised for himself monuments to his painstaking researches. His most important work, however, was done in connection with tlie gov- ernment surveys of the Territories. This work was begun as an assist- ant of Mr. Hall in the study of the then Territory of Nebraska. The principal results of this labor were published by this Academy in Vol. Y. of its Memoirs, 1855. The last twenty years of his life he was a resident of Washington, and continually engaged in the study of the rich faunre of invertebrate life from the districts beyond the Mississippi. His reports on the invertebrate life of these districts, measured by any standard, are to be ranked with the labors of the first palaeontologists in the world. The very week of his death, the writer of this notice received the last and greatest of his works, — a report on the inverte- brate cretaceous and tertiary fossils of the upper Missouri country, — a quarto volume of between six and seven hundred pages of text and nearly fifty plates. This work alone would prove the fit basis of a great reputation. It shows him to have carried his admirable powers, the unwavering fidelity, the patient courage, which he had borne through forty years of bodily weakness, unshaken to his end.

The peculiar seclusion in which Mr. Meek's life had been passed will not serve to make his loss so quickly felt as that of many another stu- dent of nature. But, though he passes from us leaving behind few connected with him by intimate friendships or even close acquaintance, there are few names in the history of American science so sure of a place for the time to come.

ADMIRAL CHARLES WILKES.

This distinguished officer entered the navy in 1818, as a midshipman. In 1826, he was made a lieutenant; in 1843, commander; in 1855, captain; in 1862, commodore; and in 1866, rear-admiral. His first cruise was up the INIediterranean ; the next on the west coast of South America, under Commodore Stewart. In 1836, he surveyed, in the " Porpoise," George's Bank, oflf" Massachusetts ; and, in 1837, Tybee Bar, at the mouth of the Savannah River. In 1838, he was selected by President Van Buren to command the South Sea Exploring Expe-

324 ADMIRAL CHARLES WILKES.

dition, which sailed from Norfolk, August 19 of that year, and returned to the United States, June 10, 1842. Many valuable contributions to science, geography, and general physics resulted from this expedi- tion. The Antai'ctic Continent was discovered Jan. 19, 1840 ; and several islands, reefs, and shoals, before unknown, were placed on the charts. In 1861, he relieved Commodore Dornin on the coast of Africa, and took command of the " San Jacinto ; " and with her capt- ured the Rebel commissioners. Mason and Slidell, who were found on board of the British mail-steamer " Trent." In July, 1862, he took command of the James River flotilla, — a large number of vessels, —^ and served on that station until the Federal troops were removed from Harrison Landing, September of the same year. He was immediately ordered to the command of the flying squadron, and sailed without de- lay for the West Indies, where his squadron did valuable service, capt- uring many vessels, until June, 1863, when he was ordered home. This was his last sea service.

At an early age he exhibited a remarkable taste for scientific pur- suits, especially astronomy and geodesy. In 1830, he took charge of the Department of Charts and Instruments, at Washington, — a new bureau. Under his supervision, a small observatory (the first) was established at Washington in 1833, when the first astronomical obser- vations, under the auspices of the government, were taken by him, with fixed instruments. In 1835, he erected on his own property, Capitol Hill, a small observatory, which was used by the government for sev- eral years. In 1837, he was sent to Europe to purchase instruments for the South Sea Exploring Expedition, then fitting out under command of Commodore Ap Catsby Jones, a duty he w^as peculiarly fitted for.

Admiral Wilkes was the author of several valuable works. The narrative of the exploring expedition — five large quarto volumes and atlas — was written by him. All the charts of the exploring expedi- tion were constructed under his supervision, comprising two large folio atlases. He wrote the hydrography of the exploring expedition. Vol. XXIII. of the series, — a large quarto volume, — and produced a quarto volume of tlie meteorological observations made during the voyage, — Vol. XI. of the series of exploring expedition works. He also pub- lished works on " Western America," the '" Theory of the Winds," " Circulation of the Ocean," and " Zodiacal Light." He was, with others, appointed by the Secretary of the Navy to examine the iron, coal, and timber regions of the Deep River District, N. C, and made an interesting report thereon, which was published by Congress in

ALEXANDER BRAUN. 32o

1858, The twenty-fourth volume of the results of the exploring expe- dition, " General Physics," was prepared by him (nearly ready for the press), but was never published, although money was appropriated by Congress for that purpose. It was to contain moon cuhninations for longitude ; transit observations of the sun and stars, for error and rate of astronomical clock ; reduced rates of clock or chronometer, by tran- sit of stars, &c., &c. ; pendulum observations — not the least valuable those made on Mauna Loa, Hawaii ; magnetic observations for vai'ia- tion, dip, and intensity ; tides, heights, and a variety of subjects, prin- cipally the result of his own observation and experience.

Admiral Wilkt^s was emphatically a hard worker, never idle ; and his eflforts in behalf of science were fully appreciated and acknowledged by many learned societies, as were also his nautical achievements. He was made the recipient (1848) of a splendid gold medal, awarded by the Royal Geographical Society of London, in acknowledgment of his discovery of the Antarctic Continent. In 1862, the merchants and citizens of Boston presented him with an elegant sword, and he was complimented with honorary membership in several scientific associa- tions in this country and abroad.

It is worthy of note, that Admiral "Wilkes, but a few days after the registering telegraph of Professor Morse was put in operation between Washington and Baltimore, in 1844, by a series of observations, having a well-rated chronometer at each end of the line, determined the differ- ence of longitude between the two cities.

ALEXANDER BRAUN.

Alexander Braun, one of the ablest botanists of our day, died at Berlin, on the 29th of March last, after a short illness. He was born at Ratisbon, May 10, 180-5, and therefore had not quite completed his 72d year. In his childhood the family removed to Carlsruhe, where his father took an appointment in the postal service, and at length be- came postmaster-general of the Grand-Duchy of Baden. Just fifty years ago, Braun was a student at the University of Heidelberg with Agassiz, Carl Schimper, and Engelmann as intimate companions. Our associate. Dr. Engelmann, is now the sole survivor. Braun, Schimper, and Agassiz soon went to ^luuich, where Oken, Schelling, DoUinger, and Martius (just returned from Brazil) were teaching:* but the party, Schimper excepted, was again united at Paris in 1832. The iiUiance with Agassiz was cemented by the marriage of the latter to Braun's sister.

326 ALEXANDER BRAUN.

Braiin's predilection for botany must have developed early ; for the long series of his communications to the scientific journals began in 1822, when he was only seventeen years old. Upon the completion of his university studies, he became Professor of Botany and Zoology in the Polytechnic School at Carlsruhe. He was transferred to the botanical chair at the University of Freiburg in the Breisgau in 1846, accepted a call to that of Giessen in 1850 ; but in 1851, upon the death of Link and Kunth, he was appointe<l Professor of Botany and Di- rector of the Botanic Garden at Berlin, where his useful life has just closed. Although the name of Braun is not connected with any dis- covery of the first order, yet he early took and has well maintained a leading position in the science. He was a botanist of wider culture and acquirement than is now common ; but his strength was given to morphology and to the systematic botany of the higher and some of the lower Cryptogamia. His earliest contribution of considerable extent and permanent importance is his memoir upon the arrangement of the scales of pine-cones, published in 1830, which opened the pro- lific and interesting subject of phyllotaxy. It is understood that the first steps in this direction were taken by Braun's fellow-student, Carl Schimper, who, however, published nothing upon the subject, either then or since : so that, practically, the development of the doctrine was left to Braun, whose memoir is classical. Next to this paper in im- portance and extent is his memoir on Rejuvenescence in Nature, especially as exemplified in the Life and Development of Plants, which first appeared at Freiburg, in 1859, and then at Leipzig in 1851 ; and which was reproduced in 1853, in an Englisli translation, by the Ray Society. This, and his paper on the Individual in Plants, which ap- peared at Berlin in 1852, are writings in which his powers of philo- sophical generalization as well as of acute observation are strikingly manifested. His systematic work, ranging over a variety of topics, is equally marked by acute insight, close observation, and scrupulous exactness. His investigations of 3Iarsilia, Isoetes, and their allies, are most complete. Upon the Gharacece his first essay bears the date of 1834, and various papers have followed from time to time; but, overtasked by official duties during all his later years, his general work upon the subject has not appeared; yet we may hope that it is left in a condition for posthumous publication. Systematic botanists of ability and experience nowhere abound. In the early part of Braun's career, Germany had its full proportion ; but owing to the almost exclusive preference for histology of late years, there are now extremely few, and the loss of a veteran like Alexander Braun will be sadly felt.

CHRISTIAN GOTTFRIED EHRENBERG. 327

CHRISTIAN GOTTFRIED EHRENBERG.

Christian Gottfried Ehrenberg died June 27, 1876, in liis eighty-second year. He belonged among the founders of our present zoologj', and was the first to treat in a scientific way that mass of minute beings formerly included in the vague term " Infusoria." With the synchronism that often marks valuable discoveries, it happened that considerable improvements in the microscope were made about the time he began his favorite investigations, and the demands of his sub- ject led him ever to encourage and aid such improvements.

In 1830 appeared his great work on living infusoria, with admirable plates from his own hand. His interpretation of forms so novel was naturally influenced by previous ideas of organization in the animal kingdom ; so that to many of them he attributed oi-gans more or less defined, and a certain complication of structure. As microscopy pro- gressed, these views were modified and corrected by the observers he had trained, or who had been stimulated hj his example. The studies of Schwann and Henle on the nature and development of the cell gave a new interpretation to these microscopic creatures. Some were found to be unicellular plants, and others proved the embryos of sponges, and to be even of articulated or radiated animals. But all such corrections were simply the unvarying steps that mark discovery. Ehrenberg it was who took the first step, and who, to the end, remained the master- spirit in this field.

In 1840 appeared his chief work on the fossil infusoria, which ex- hibited their extraordinary part in building geological formations, whether as a fine sand (Bergmehl), or in more compact forms. He showed that some cretaceous foraminifera are still living, and explained in advance the structure of portions of the deep-sea bottom which have recently been examined by the dredge. The number of these low or- ganisms, figured in his chief works and in his numerous minor publica- tions, is so great as to give data for their geographical and geological distribution over a large portion of the globe.

It must not be thought that Ehrenberg was a specialist of the narrow type which is, unfortunately, so common to-day. He was a man learned in all branches of natural history, and had grown side by side with the science he fostered. Although he spent the greater part of his life in his native Prussia, he travelled a good deal. Having studied at first theology, and afterwards medicine, at Leipzig, he moved, in 1817, to Berlin, and there devoted himself to what proved to be the occupation of his life. From 1820 to 1825, he travelled with Hemprich in Arabia,

828 WILHELM FRIEDBICH BENEDICT HOFAIEISTER.

Egypt, and Nubia, and brought back to his patrons of the Berlin Academy a rich collection. He published from it " The Corals of the Red Sea," a work which gave him a high reputation. In 1829, he went with Humboldt to the Ural Mountains; and, in 1839, he received the appointment of professor in the University of Berlin.

Ehrenberg enjoyed the advantage that originality gives. He helped build up zoology, and he created a special department in its study. Thus it was easy for him to keep on the crest of the front wave. All the labors of his followers only added to his power and elevation.

WILHELM FEIEDRICH BENEDICT HOFMEISTER.

"WiLHELM Friedrich BENEDICT HoFMEiSTER, the distinguished vegetable anatomist, and the successor of von Mohl in the chair of Botany at the University of Tubingen, died on the 12th of January last, in the 53d year of his age. He was born at Leipzig, May 18, 1824, where his father was a publisher ; and the son entered upon the same profession, devoting, however, his leisure to microscopical research. His first memoir, which established his reputation, viz., that on the formation of the embryo in plants {Die Entstehung des Embryo der Phanerogamen), was published at Leipzig in the year 1849. These researches were confined to the monocotyledonous and proper dicoty- ledonous plants. It was followed, in 1851, by his still more impor- tant and elaborate researches upon the development and fructification of the higher Cryptogaraia and the Coniferae ; and soon after ap- peared another memoir upon the Vascular Cryptogamia {Beitrage ziir Kentniss der Gefcisskryptogamen). In 1859 and 1861, he brought out the results of his new investigations upon the formation of the embryo in phanerogamous plants. His minor contributions to the journals of the day are numerous, all relating to vegetable anatgmy and develop- ment. Called now to the chair of Botany in the University of Heidel- berg, he undertook the preparation of a text-book, viz., the Handbuch der Physiologischen Botanik, in connection with DeBary, Jrmisch, and Sachs ; each taking a particular department. Hofmeister pub- lished the main anatomical part {Die Lehre von der PJianzenzelle) in 1867, and the morphological {Allgemeine Morphologie der Gewclchse) in 1868. Since his translation to Tubingen, in the autumn of 1872, only minor papers have appeared, to testify that his wonderful energy was not exhausted. Hofmeister was a worthy successor of Mohl ; but the contrast is striking. Mohl published far too little ; but all that he wrote was clear and plain. Although the value of Hofmeister's work

CHRISTIAN LASSEN.

329

may be well proportioned to its amount, and although his earlier writ- ings are not wanting in perspicuity, it is reported that his fellow- laborers among his own countrymen find it difficult to understand his later publications.

CHRISTIAN LASSEN.

Among the many illustrious scholars who have passed away during the last year, none had achieved a higher or more deserved fame than Christian Lassen, of Bonn. He was a native of Norway, born at Bergen almost with the century, or late in 1800; and he died on the 8th of May last. The weakness of age, with a growing infirmity of eyesight, which rendered him during all the last years of his life nearly blind, has withdrawn him for some time from the ranks of the active workers, and given him the aspect of a survivor from a past genera- tion. He belongs, indeed, to the little band of men who inaugurated in Europe the study of India through its own sacred language, the Sanskrit ; and he was the last of them yet left in life. It is striking and strange that there should have died so recently one whose activity as a scholar covered the whole history of a branch of knowledge which lias assumed such importance and prominence, which has yielded such great results, and become an acknowledged necessity to an education in philology. Lassen was led to take up Sanskrit by the influence of A. W. von Schlegel, under whom he first studied at Bonn, becoming afterwards his collaborator, and his successor. The (incomplete) Rama- yana, the Bliagavadgita, and the Hitopade^a, were the works in whose preparation he took more or less part : the two last of these, especially, are still authoritative, unsurpassed in method and merit of execution. In 1827 appeared his first two works: the celebrated Essai sur le Pali, prepared in company with Burnouf, and a geographical and his- torical dissertation on the Penjab, which was the forerunner of his gigantic ladlsche AlterthumsTcunde, the principal labor of his life. This began to appear in 1847, and was broken off" with the fourth volume in 1861—62, by reason of its author's physical infirmities; al- though he was still able to produce a second edition of the first two volumes, rewritten and enlarged, in 1867-74. It was the misfortune of this work, meritorious as it is, that it was begun too soon for the results of the Vedic researches to be brought fully into its early por- tions. The study of India, indeed, was and still is in too inchoate a state to admit of its results being cast into any thing like a permanent form. Apart from those already mentioned, Lassen's principal con- tributions to this department of learning were an edition of the

330 JOHANN CHRISTIAN POGGENDORFF.

Gitagovinda, with notes and Latin version ; part of the drama Malati- Madhava ; a Sanskrit Anthology, with glossary ; and an elaborate Prakrit grammar : also, a host of important articles in Oriental journals. Of the Zeitschrift fur die Kunde des Morgenlandes he was long editor and chief author. He by no means, however, confined his studies to India. His aid in the decipherment of the Persian cuneiform inscriptions was very important ; and he tried his hand also, with effect, yi])0\x the Umbrian. The Zend and modern Persian were subjects included in his University lectures.

Lassen was admirable for singleness and simplicity of character, freedom from affectation or pedantry, and courtesy and helpfulness to his pupils. A contented cheerfulness of disposition, too, was a striking characteristic. Few men have combined a life so splendid in the eyes of the learned world with such narrowness of means and such physical trials. The failing of his eyes, probably brought on by excessive use in difficult collations, began to grow serious after 1840 ; and it was fol- lowed by other weaknesses, which compelled him to spend the greater part of his time i-eclining on a lounge, and to be wheeled about in a chair. His lectures came to an end in 1864. His last literary work was done by the aid of his wife and of a reader and amanuensis. He lost until the very end neither his memory nor his keen interest for every thing that bore upon the studies of his life. He was married in 1849, and leaves no children.

JOHANN CHRISTIAN POGGENDORFF.

The story of the noble and useful life of Johann Christian Poggen- dorff may be told in a few words. He was born at Hamburg, Dec. 29, 1796 ; received his early education at the Gymnasium in that city ; and at the age of sixteen entered the shop of an apothecary, where he re- mained eight years. In 1821, he became a student in the University of Berlin, and in the following year published his first paper, in which he described the galvanometer, since, in its improved form, so necessary an instrument of physical research. The true work of his life began in 1824, when he issued the first number of the '• Annalen der Pliysik und Chemie " as a continuation of the " Annalen der Physik " of Gil- bert. During fifty-three years, Poggendorff directed the publication of the "Annalen," — the noblest scientific periodical which has ever appeared, the one work which is indispensable to the student of physi- cal science. Every important memoir in any department of physics appeared in this journal. Almost the whole scientific life of Berzelius,

KARL ERNST VON BAER. 331

Faraday, Mellon!, Magnus, the two Roses, Mitscherlich, Regnault, and a host of others, is written in its pages, and a large proportion of the translations from foreiijn lansjuaores were the work of the editor alone. After fifty years of his unassuming labor, Poggendorff's friends united in contributing to a " Jubelband," or jubilee volume, in honor of the anniversary of his connection with the " Annalen ; " and a goodly tome filled with oriirinal memoirs marked the besinning of the second half- century of his life-work. A short time before his death, Poggendorff sought to give the "Annalen" a still wider range of usefulness by the occasional publication of " Beibliitter," or supplements, containing brief abstracts of the work of foreign investiojators. The first number of this supplement appeared only a few days before his death. It might well be thought that the superintendence of the "Annalen" would be work enough for one man. But Poggendorff found time for original researches in several branches of physics, chiefly in electricity and magnetism. We owe to him the invention of the method of measuring small angular variations by means of a plane-mirror telescope and scale, now in constant use. To chemistry he contributed the method of indi- rect analysis, which is frequently of great value. The list of his pub- lished papers embraces more than one hundred and thirty titles. In 1863, he published, in two large volumes, the well-known " Biographisch- literarisches Handworterbuch zur Geschichte der exacten Wissenchaf- ten," — the worthy forerunner of the noble work of the Royal Society, and in itself a monument of careful labor. In Berlin, Poggendortf was surrounded by a circle of warmly attached friends. He was him- self the type of the German scientist. Of unusual discrimination and critical ability, — laborious, jjatient, untiring, — he worked in his own vocation for nearly sixty years " without haste and without rest." Per- sonally, he was kindly, genial, and hospitable, perfectly free from osten- tation, with the heartiest sympathy for the student of science, and the most cordial ajjpreciation of the work of others. On the 24th of January last, in his eighty-first year, he died, leaving a name honored wherever science is honored, cherished and loved by all who knew the man.

KARL ERNST A^ON BAER.

Karl Ernst Von Baer was born the 29th Feb., 1792, at Piep, the estate of his father in Esthonia, and died at Dorpat, aged eighty-four. It was a long life devoted to intellectual work, and, though it included active periods of travel and exploration, its most memorable events be- long to the laboratory and are to be found in the annals of scientific

'832 KARL ERNST VON BAER.

research during two-thirds of a century. The opening and closing scenes of liis life were closely connected ; fur at Dorpat, in the early days of the University (1810-14), he received his collegiate education and his doctor's diploma, and there he retired to devote the quiet decline of his old age to his favorite studies, interrupted only by his death, Nov. 28, 1876. Although he graduated as a physician, he left the university at twenty-one years of age with a strong bent for natural history, strength- ened by the influence of the botanist. Professor Ledebour, and the phjrsiologist, Burdach. But to the naturalist in those days, unless fortune had made him independent, no path was open except that of medicine. The study of disease, with its accompanying branches of comparative anatomy and physiology, was the indirect road to the study of nature. Yet the young Von Baer struggled manfully with his predilection, and on his way to Vienna where he went to acquire practical familiarity with his profession, though keen to observe every thing of interest, he himself tells us tliat he avoided collections, as he would have done "a consuming fire." At Vienna, he tried, by throwing himself with new ardor into his professional work, to forget his passion for natural history. To this ob- ject, however, his excursions in the neighborhood, on which he allowed himself to botanize and geologize a little, were by no means favorable. On one of these rambles, somewhere in the environs of Salzburg, he fell in with Martius, the botanist, and this chance meeting proved a turning point in his career. Martius told him to go and study with Dollinger at Wiirzburg, and gave him as an introduction a package of mosses to be delivered to him. One of the most pleasing passages in his autobiography is that in which he describes himself as coming full of hope into the presence of the professor ; handing the package, and stating at the same time his desire to attend his course on comparative anatomy. "I do not lecture on comparative anatomy this term," an- swered Dollinger, in the quiet, slow manner peculiar to him, at the same time opening the package and examining the mosses. As the young man stood for a moment silent and bewildered in his disappointment, the professor looked up again and said, " Why lectures ? Bring an animal and dissect it here, and then another." The difficulty was solved. The young student appeared the next morning with a case of instruments and a leech purchased at an apothecary's shop. From that time, his table was in the laboratory of Dollinger, who was not slow to recog- nize in his new pupil a naturalist of the first order. A true teacher, Dollinger was lavish of his intellectual capital, giving to his pupils with generous disregard of his own scientific riglits, the results of his original and unpublished investigations. His unselfishness was appre-

KARL ERNST VON BAER. ' 333

ciated by his pupils, and by none more than Von Baer, wlio speaks of him as his " worthy, well beloved, deeply revered teacher." During his stay at Wiirzburg, Von Baer became intimate with Pander, then beginning, under the direction of Dollinger and with the assistance of Dalton, the great series of embryological investigations, in which Von Baer afterward took so prominent a part, and which has made the names of all three, Dollinger, Von Baer, and Pander, synonymous with the science of embryology. Pander's embryology of the chick first gave the clew to Kaspar Friedrich Wolff's descriptions, and the connection of Von Baer with Pander's researches led him to investi- gations long unnoticed, and barely appreciated even now in thei/ full value and significance, tliough they have gained for him the title of the founder of modern embryology.

The doubts as to his future career were happily solved at the close of his two years' residence in Wiirzburg by a letter from Burdach his former professor in Dorpat, offering him a place as assistant in the newly founded anatomical department in the University of Kbnigsberg. This he gladly accepted, and, after a winter spent in Berlin in prepara- tion for his new office, we find him established in 1817 at Konigsberg. He entered on his duties with energy and success, cheered by seeing his old professor amon^ the regular attendants at his lectures. His knowledge of the lower animals w3s extensive ; and, though compelled to give his time chiefly to human anatomy, he made a series of prepa- rations intended as the basis of a small museum. In 1819, through the influence of his colleague, Schweigger, he was appointed professor of zoology, with an additional salary of 300 thalei's, and the understanding that he was to build up a great museum for the University of Konigs- berg. With his prospects thus improved, he now married Friiuleiu von ]\Ieden, and felt himself bound by new ties to Konigsberg, where -he remained till 1829. It was a brilliant period in the life of the university when, beside Von Baer, its faculty could boast of men like Schweigger, Schubert, Jacobi, Bessel, Struve, Lobech and the older Hagea. On Schweigger's death, Von Baer was made regular professor of natural history and zoology, with a considerable increase of salary, virtually diminished, however, by the necessity of purchasing books for his department, which the university found itself too poor to supply. His professional duties, combining instruction to the medical and zoolo- gical students with the care of the museum, were now very onerous. With all his energy and devotion, the museum moved far too slowly for his zeal. Occasionally, he was cheered by donations or by collections contributed from distant lands ; and he succeeded in enlisting the sym-

834 KARL ERNST VON BAER.

patliies of the minister of public instruction and of the professors of the university. But the very modest allowance he received from the university, spite of occasional aid from outside, forced upon him a dis- couraging economy in the administration of the museum.

In the midst of all these professional duties, he found time for his spe- cial studies in geology, anthropology, and anatomy, and continued his systematic observations in embryology. As early as 1818, he had laid the foundation of his great generalization on the distinct modes of de- velopment for the four great branches of the animal kingdom, and in 182G he published, in Burdach's ''Physiology," his embryology of the chick and frog. Chiefly attracted by the development of Vertebrates, he first showed the identity of the mammalian egg, including that of man, with the (^gg of fishes. These results first appeared in the memorable treatise entitled " De Ovi Mammalium et Hominis Genesi," in 1827. It was in advance of the time, and, with the exception of a sneering comment on the egg found by a great man in the ovary of a woman, was hardly mentioned in the annual scientific reports of the day. The light thrown upon this paper by the writnigs of a later set of embryologists, Rathke, Bischoff", and Kolliker, first made known the vast importance of the theory of embryonic layers announced by Von Baer. It was followed in 1828 by the first volume of his " Entwicke- lungsgeschichte ; " but it was only in 1831 that Von Baer was rewarded by the French Academy with one of its prizes. The Eng- lish were even slower to recognize his merit, and the first English translation of the most important biological work of the century, the " Entwickelungsgeschichte " appeared only in 1855.

In 1829, Von Baer was invited to take charge of the zoological department in the Academy of St. Petersburg. He had, however, a certain distrust of the position from the long-continued delay in the publication of the great work of Pallas. On this account, although they were inclined to grant all he asked, he decided to remain at Konigsberg, making it a condition, however, that he should have cer- tain facilities for his embryological investigations. He now devoted himself especially to his investigations on the special modes of devel- opment characterizing the principal types of the animal kingdom, the results of which were embodied in the second volume of his " Ent- wickelungsgeschichte." During the second period of his Konigsberg life, the social and ^wlitical circumstances became less favorable to his aims, and in 1832 he renewed his negotiations with St. Petersburg; this time with a different result, for in 1834 we find him established there. He now entered on a life of greater activity and variety than

KARL ERNST VON BAER. 335

any he had hitherto known. Under the auspices of the academy, he made a number of journeys first to Lapland and Nova Zerabhi, and later in the interests of the fisheries to the Volga, Lake Peipns, and the Caspian Sea. He published full reports of all these explorations, and remained a most active member of the Academy till 1862, when he was made an honorary member.

Von Baer was a strong believer in development, but an uncompro- mising opponent of Darwinism, one of his last papers being a protest against the assumed descent of Vertebrates from Ascidians. The breadth of his culture, his great learning, his native simplicity of character, are nowhere better shown than in the volumes of his col- lected addresses, more popular essays and lectures. While, however, he inclines to make knowledge accessible to all, he speaks with quiet contempt of the dilettante science. Phytogeny, — if we may so call it, — which threatens to drown all serious investigations under its fan- tastic theories.

A few men in every century leave the tide line of human knowl- edge higher than they found it. Von Baer was one of these. Less brilliant perhaps than Cuvier, he is equally identified with the theory of types ; and the fame of Von Baer may even outrun that of his great contemporai-y, since to embryology rather than to any other science we may look for the elucidation of the prominent biological problems of the day.

Since the last Report, the Academy has received an acces- sion of eighteen new members : three Fellows, A. Graham Bell, B. H. Nash, W. E. Story ; seven Associate Fellows, William Ferrel, J. L. Diman, Thomas Hill, George Mary Searle, Henry Larcom Abbott, Nathaniel Holmes, Richard Saltonstall Greenough ; eight Foreign Honorary Members, Ei-nst Curtius, F. A. A. Mignet, James Paget, jNIark Pattison, H. C. Rawlinson, A. P. Stanley, Alfred Tennyson, Viollet- Le-Duc. On the other hand, by removal from the State or by resignation, the following Fellows have abandoned their membership : Francis Bowen, Edward C. Cabot, William Ferrel, George S. Hillard, Ira Remson, William E. Story. The list of the Academy corrected to June, 1877, is hereto added. It includes 181 Fellows, 96 Associate Fellows, and 72 For- eign Honorary Members.

LIST

OF THE FELLOWS AND FOREIGN HONORARY MEMBERS.

June 14, 1876.

FELLOWS. — 181.

(Number limited to two hundred.)

Class I. — Mathematical and Physical Sciences. — 58.

Section I. —

Mathematics.

7.

Ezekiel B. Elliott, Benjamin A. Gould, Gustavus Hay, Benjamin Peirce, James M. Peirce, John D. Runkle, Edwin P. Seaver,

Washington.

Cordoba.

Boston.

Cambridge.

Cambridge.

Boston.

Boston.

Section IT. — 8. Practical Astronomy and Geodesy. J. Ingersoll Bowditch, Boston.

Alvan Clark, Henry Mitchell, Robert Treat Paine, E. C. Pickering, William A. Rogers, L. Trouvelot, Henry L. Whiting,

Cambridgeport. Roxbury. Boston. Cambridge. Cambridge. Cambridge. Boston.

Section III. — 26.

Physics and Chemistry.

John Bacon, Boston.

A. Graham Bell, Boston.

John H. Blake, Boston.

Thos. Edwards Clark, Williamstown.

W. J. Clark, Josiah P. Cooke, Jr. James M. Crafts, William P. Dexter, Charles W. Eliot, Moses G. Farmer, Wolcott Gibbs,

Amherst.

Cambridge.

Boston.

Roxbui'y.

Cambridge.

Newport.

Boston.

Augustus A. Hayes, Henry B. Hill, '

Eben N. Horsford, T. Sterry Hunt, Charles L. Jackson, Joseph Lovering, John M. Merrick, William R. Nichols, John M. Ordway, Edward S. Ritchie, S. P. Sharpies, Frank H. Storer, John Trowbridge, Cyrus M. Warren, Charles H. Wiug,

Brookline. Cambridge. Cambridge. Boston. Cambridge. Cambridge. Boston. Boston. Boston. Boston. Cambridge. Jamaica Plain. Cambridge. Brookline. Boston.

Section IV. ~17. Technology and Engineering.

G. R. Baldwin, Woburn.

John M. Batchelder, Cambridge.

C. O. Boutelle, Washington.

Henry L. Eustis, Cambridge.

James B. Francis, Lowell.

John B. Henck, Boston.

John C. Lee, Salem.

William R. Lee, Roxbury.

Hiram F. JMills, Lawrence.

Alfred P. Rockwell, Boston.

John Rodgers, Washington.

Stephen P. Ruggles, Boston.

Charles S. Storrow, Boston.

John H. Temple, W. Roxbury.

William R. AVare, Boston.

William Watson, Boston.

Morrill Wyman, Cambridge.

FELLOWS.

337

Class II. — Natural and Physiological Sciences. — 66.

Section I. — 11.

Geology, Mineralogy, and Physics of the Globe.

Thomas T. Bouve, William T. Brigham, Algernon Coolidge, John L. Hayes, Charles T. Jackson, Jules Marcou, Raphael Pumpelly, William B. Rogers, Nathaniel S. Shaler, Charles U. Shepard, Josiah D. Whitney,

Boston.

Boston.

Boston.

Cambridge.

Boston.

Cambridge.

Boston.

Boston.

Cambridge.

Amherst.

Cambridge.

Section n. — 10. Botany.

Jacob Bigelow, George B. Emerson, WilHam G. Farlow, George L. Goodale, Asa Gray, H. H. Hunnewell, John A. Lowell, Chas. J. Sprague, Edward Tuckerman, Serene Watson,

Boston.

Boston.

Boston.

Cambridge.

Cambridge.

Wellesley.

Boston.

Boston.

Amherst.

Cambridge.

Section IIL — 26.

Zoology and Physiology.

Alex. E. R. Agassiz, Cambiidge.

J. A. Allen, Cambridge.

Robert Amory, Brookline.

Nath. E. Atwood, Provincetown.

James M. Barnard, Boston.

Henry P. Bowditch, Boston.

Thomas M. Brewer, Boston.

Samuel Cabot, Boston.

John Dean, Waltham.

Silas Durkee, Boston.

Herrmann A. Hagen, Cambridge.

C. E. Hamlin, Cambridge. Alpheus Hyatt, Cambridge. Wm. James, Cambridge. Samuel Kneeland, Boston. Theodore Lyman, Boston. John McCrady, Cambridge. Edward S. Morse, Salem. Alpheus S. Packard, Jr., Salem. Charles Pickering, Boston.

L. F. Pourtales, Cambridge.

Frederic W. Putnam, Cambridge. Samuel H. Scudder, Cambridge.

D. Humphi'eys Storer, Boston. Henry Wheatland, Salem. James C. White, Boston.

Section IV Medicine and

Samuel L. Abbot, Henry J. Bigelow, Henry I. Bowditch, Edward H. Clarke, Benjamin E. Cotting Thomas Dwight, Robert T. Edes, Calvin Ellis, Richai'd M. Hodges, Oliver W. Holmes, R. W. Hooper, John B. S. Jackson, Edward Jarvis, Edward Reynolds, Horatio R. Storer, John E. Tyler, J. Baxter Upham, Charles E. Ware, Henry AV. Williams,

. — 19. Surgery.

Boston. Boston. Boston. Boston. , Roxbury. Boston. Roxbury. Boston. Boston. Boston. Boston. Boston. Dorchester. Boston. Boston. Boston. Boston. Boston. Boston.

VOL. XII. (x. s. iv.)

22

338

FELLOWS.

Class III. — Moral and Political Sciences. — 57.

Section I. — 15.

Philosophi/ and Jurisprudence.

George Beinis. George T Bigelow, Richanl II. Dana, Jr. C. C. Everett, Horace Gray, Frederic H. Hedge, L. P. Ilickok, Ebenezer R. Hoar, Mark Hopkins, C. C. Langdell, Henry W. Paine, Theophilns Parsons, Charles S. Peirce, Benjamin F. Thomas, Francis Wharton,

Sectiox H. — 12.

Philolo[iy and ArchcEology .

Ezra Abbot, William P. Atkinson, H. G. Denny, Epes S. Dixwell, William Everett, William W. Goodwin, Ephraim W. Gurney, Bennett II. Nash, Chandler Kobbins, John L. Sil)ley, E. A. Sophocles, Edward J. Young,

Cambridge.

Boston.

Boston.

Cambridge.

Cambridge.

Cambridge.

Cambridge.

Boston.

Boston.

Cambridge .

Cambridge.

Cambridge.

Section HI. — 16. Political Economjj and History.

Boston.	Chas. F. Adams, Jr.,	Quincy.
Boston.	Henry Adams,	Boston.
, Boston.	Erastus B. Bigelow,	Boston.
Cambridge.	Caleb Cushing,	Newburypoi't
Boston.	Charles Deane,	Cambridge.
Cambridge.	Charles F. Dunbar,	Cambridge.
Northampton.	Samuel Eliot,	Boston.
Concord.	George E. Ellis,	Boston.
Williams town.	E. L. Godkin,	Cambridge.
Cambridge.	WilUam Gray,	Boston.
Cambridge.	Edward Everett Hale	Boston.
Cambridge.	Francis Parkman,	Brookline.
Washington.	A. P. Peabody,	Cambridge.
, Boston.	Nathaniel Thayer,	Boston.
Cambridge.	Henry W. Torrey,	Cambridge.
	Robert C. Winthrop,	Boston.

Section IV. — 14. Literature and the Fine Arts.

Charles F. Adams, William T. Andrews, George S. Boutwell, J. Elliot Cabot, Francis J. Child, Ralph Waldo Emerson John C. Gray, Henry W. Longfellow, James Russell Lowell, Charles Eliot Norton, John K. Paine, Thomas W. Parsons, Charles C. Perldns, John G. Whittier,

Boston.

Boston.

Groton.

Brookline.

Cambridge.

, Concord.

Cambridge.

Cambridge.

Cambridge.

Cambridge.

Cambridge.

Wellesley.

Boston.

Amesbury.

ASSOCIATE FELLOWS.

889

ASSOCIATE FELLOWS. — 96.

(N'limber limited to one hundred.)

Class L — Mathematical and Pliysical Sciences. — 36.

Section I. — 7. Mathematics.

Charles Avery, "William Ferrel, Thomas Hill,

Clinton, N.Y. Washington. Portland, Me.

Simon Newcomb, Washington, D. C. H. A. Newton, New Haven, Conn. James E. Oliver, Ithaca, N.Y. T.H. Safford, Williamstown, Mass.

Sectiox n. — 11.

Practical Astronomy and Geodesy.

S. Alexander, Princeton, N.J.

W.H.C.Bartlett, West Point, N.Y.

J. H. C. Coffin, Washington, D.C.

Wm. H. Emory, J. E. Hilgard, George W. Hill, Elias Looniis,

Washington, D.C. Washington, D. C. Nyack, N.Y. New Haven, Conn.

Maria ^litchell, Poughkeepsie, N.Y''. C. H. F. Peters, Clinton, N.Y. George M. Searle, New York. Chas. A. Young, Hanover, N.H.

Section HI. — 12.

Physics and Chemistry.

F. A. P. Barnard, New York. John W. Draper, New York. Joseph Henry, Washington, D.C. S.W.Johnson, New Haven, Conn. John Le Conte, San Francisco, Cal. A. M. Mayer, Hoboken, N.J. W. A. Norton, New Haven, Conn. Ogden N. Rood, New York. H. A. Rowland, Baltimore. L.INI. Rutherfm'd, New York. Benj. Silliman, Ne-w Haven, Conn, J. L. Smith, Louisville, Ky.

Section IV. — 6.

■ Technology and Engineering.

Henry L. Abbot, New York. R. Delafield, AVashington.D.C.

A.A.Humphreys, "Washington, D.C. Wm. Sellers, Philadelphia. George Talcott, Albany, N.Y. W.P.Trowbridge, NewHaven, Conn.

Class II. — Natural and Physiologiccd Sciences. — 29.

Section I. — 13.

Geology, Mineralogy, and Physics of the Globe.

George J. Brush, New Haven, Conn. James D. Dana, New Haven, Conn. J. W. Dawson, Montreal, Canada. Edward Desor, Neufchatel, Switz.

J. C. Fremont, F. A. Genth, Arnold Guyot, James Hall, F. S. Holmes, JosejDh Leconte, J. Peter Lesley, Wm. T. Roepper, Geo. C. Swallow,

New York. Philadelphia. Princeton, N.J. Albany, N.Y. Charleston, S.C. San Francisco. Philadelphia. Bethlehem, Pa. Columbia, Mo.

S40

ASSOCIATE FELLOWS.

Section II. — 4.

Botany.

A. W. Chapman, Aijalachicola, Fla. G. Engelmann, St. Louis, Mo. Leo Lesquereux, Columbus, Ohio. S. T. Oluey, Providence, R.I.

Section III. — 9.

Zoology and Physiology.

S. F. Baird, Washington, D.C.

C. E. Brown- Sequard, London. J. C. Dalton, New York.

J. P. Kirtland, Cleveland, Ohio. J. L. LeConte, Philadelphia. Joseph Leidy, Philadelphia. O. C. Marsh, New Haven, Conn. S. Weir Mitchell, Philadelphia. St. JuUen Ravenel, Charleston, S.C.

Section IV. — 3.

Medicine and Surgery.

W. A. Hammond, New York. Isaac Hays, Philadelphia.

George B. Wood, Philadelphia.

Class III. — Moral and Political Sciences. — 31.

Section I. — 7.

Philosophy and Jurisprudence.

D. R. Goodwin, Philadelphia. R. G. JIazard, Peacedale, R.I. Nathaniel Holmes, St. Louis, Mo. James McCosh, Princeton. Noah Porter, New Haven, Conn. Isaac Ray, Philadelphia.

Jeremiah Smith, Dover, N.H.

Section II. — 11.

Philology and Archceology.

A. N. Arnold,

D. C. Gilman, S. S. Haldeman, A. C. Kendrick, Geo. P. Marsh, L. H. Morgan, A. S. Packard,

E. E. Sahsbury,

Hamilton, N.Y. Baltimore. Columbia, Pa. Rochester, N.Y. Rome.

Rochester, N.Y. Brunswick, Me. New Haven, Conu.

A. D. White, Ithaca, N.Y.

W. D. Whitney, New Haven, Conn.

T. D. Woolsey, New Haven, Conn.

Section IH. — 8. Political Economy and History.

S. G. Arnold, Geo. Bancroft, S. G. Brown, Henry C. Carey, J. L. Diman, Henry C. Lea, Barnas Sears, J. H. Trumbull,

Newport, R.I. Washington. Clinton, N.Y. Philadelphia. Providence, R.I. Philadelphia. Scranton, Va. Hartford.

Section IV. — 5.

Literature and the Fine Arts. James B. Angell, Ann Arbor, Mich. Wm. C. Bryant, New York. F. E. Church, New York. R. S. Greenough, Florence. Wm. W. Story, Rome.

FOREIGN HONORARY MEMBERS.

341

FOREIGN HONORARY MEMBERS. — 72.

(Appointed as vaoancies occur.) Class I. — Mathematical and Physical Sciences. — 25.

Section I.	— 8.	Section I	II. — 11.
Mathematics.	Physics and	Chemistry.
John C. Adams,	Cambridge.	R. Bunsen,	Heidelberg.
Sir George B. Airy,	Greenwich.	E. Chevreul,	Paris.
Brioschi,	Milan.	J. Dumas,	Paris.
Arthur Cayley, Chasles,	Cambridge. Paris.	H. Helmholtz, A. W. Hofmaun,	Berlin. Berlin.
Le Terrier,	Paris.	G. Kirchhoff,	Berlin.
Liouville,	Paris.	J. C. Maxwell,	Cambridge.
J. J. Sylvester,	Woolwich.	V. Regnault, Balfour Stewart,	Paris. Manchester
Section II	.—4.	G. G. Stokes, F. Wohler,	Cambridge. Gbttingen.
Practical Astronomy DoUen, H. A. E. A. Faye,	and Geodesy. Pulkowa. Paris.	Section IV. — 2. ^ Technology and Engineering.
Peters,	Altona.	R. Clausius,	Bonn.
Otto Struve,	Pulkowa.	Sir Wm. Thomson	Glasgow.

Class II. — Natural and j

Section I. — 8.

Geology, Mineralogy, and Physics of the Globe.

Barrande, Prague.

Charles Darwin, Beckenham.

H. W. Dove, Berlin.

James Prescott Joule, Manchester.

AV. H. Miller, Cambridge.

C. F. Rammelsberg, BerUn.

A. C. Ramsay, London.

Sir Edward Sabine, London.

Physiological Sciences.	25.
Section II.	— 6.
Botany.
George Bentham,	London
Decaisne,	Paris.
Alphonse de CandoUe,	•Geneva.
Elias Fries,	Upsal.
Oswald Heer,	Zurich.
Joseph Daltou Hooker,	London

342

FOREIGN HONORARY MEMBERS.

Section TIT. — S.

Zoology and Pliysiolorjij.

T. L. W. Bischoff, Munich. Milno-Edwards, Paris.

Albrecht Kiilliker, "Wiirzburg. Rudolph Leuckart, Leipzig. Richard Owen, London.

C. Th. Von Siebold, Munich.

J. P. Steenstrup, Valentin.

Copenhagen. Berne.

Section IV. — 3. Medicine and Surgery. Sir James Paget, London.

Rokitansky, Virchow,

Vienna. Berlin.

Class III. — Moral and Political Sciences. — 22.

Section I. — 4. Philosophy and Jurisprudence.

T. C. Bluntschli, Sumner Maine, James INIartineau, Sclopis di Salerano,

Heidelberg. London. London. Turin.

Section II. — 6.

Philology and Archaeology.

Pascual de Gayangos, Madrid. Benjamin Jowett, Oxford. Sir n. C. Rawlinson, London. Lepsius, Berlin.

Max Miiller, Oxford.

F. Ritschl, Leijjzig.

Section III. — 9.

Political Economy and History.

Ernst Cui'tius, Berhn. W. Ewart Gladstone, London.

Charles Merivale, Oxford.

F. A. A. Mignet, Paris.

Mommsen, Berlin.

Mark Pattison, Oxford.

Von Ranke, Berlin.

A. P. Stanley, London.

Thiers, Paris.

Section IV. — 3.

Literature and the Fine Arts.

Gerome, Paris.

Alfred Tennyson, Isle of Wight.

VioUet-Le-Duc,

Paris.

INDEX TO YOL. lY.

Abronia Cnix-Maltse, 253.

cycloptera, 253.

niicrantha, 253. Acanthophora Delilei, 237.

luuscoides, 237. Acerates, 66, 72.

angustifolia, 72.

auiiculata, 72.

lanuginosa, 73. ,

longifolia, 73.

paniculata, 66.

tomentosa, 73.

viridiflora, 73. Acid, Diamido-sulphobenzide-di- carbonic, 205.

Parabro m alph atoluylic , 223 . Air, Effect of Temperature on Vis- cosity of, 41. Alga, Xew, of California, 245. Algpe, on some new to the United

States, 235. Amarantus albus, 274.

blitoides, 273.

Blitum, 273.

firabriatus, 274.

Greggii, 274.

obovatus, 275.

Palmeri, 274.

Torreyi, 274.

AVrigbtii, 275. Amblogyne, 274. Ammonic parabromalphatoluate,

224. Amphidium molybdoplaciim, 182. Amphiroa Californica, 238.

cuspidata. 239.

debilis, 239.

fragilissima, 239.

nodulosa, 239.

Orbigniana, 238.

Amphiroa Triliulus, 239.

tuberculosa, 239.

vertebralis, 239. Amsonia brevifolia, 64.

longifiora, 64.

Palmeri, 64.

tomentosa, 64. Anautherix, 66.

connivens, 66.

decumbens, 66.

paniculatus, 66.

viridis, 66. Angelica leporina, 252. Antigeny, or Sexual Dimorphism,

in Butterflies, 150. Antirrhinimi chytrospermum, 81.

cyathiferum, 81. Appropriations, 279, 283. Arctomecon, Character of, 52. Arctostaphylos Clevelandi, 61. A]-gentic parabromalphatoluate,

224. Arsenite of Copper, Experiments

upon, 11. Asclepias, 65.

anioena, 67.

amplexicaulis, 67.

angustifolia, 70, 71, 72.

arenaria, 68.

brachystephaija, 68.

cinerea, 72.

Cornuti, 67.

Coulteri, 71.

cryptoceras, 67.

Curassavica, 66.

debilis, 70.

Douglasii, 67.

eriocarpa, 68.

erosa, (iS.

fascicularis, 71.

Feayi, 72.

Fremonti, 68.

344

INDEX.

t..

Asclepias galioides, 71. glaucescens, 67. Hallii, 69. humistrata, 67. iucarnata, 67. involucrata, 69. Jamesii, 68. lanceolata, 66. leucophylla, 68. Lin aria, 71. linearis, 70, 71. Lindheimeri, 72. linifolia, 70. longicornu, 72. macrophylla, 71. macro tis, 69. Meadii, 67. Mexicana, 71. Michauxii, 72. nivea, 68, 70. niimmularia, 67. Nuttalliana, 69.

nyctaginifolia, 69.

obovata, 69.

obtusifolia, 67.

ovalifolia, 69.

parviflora, 70.

paupercula, 66.

perennis, 70.

phytolaccoides, 68.

purpurascens, 67.

quadrifolia, 70.

quinquedentata, 71.

rubra, 67.

speciosa, 67.

stenophylla, 72.

snbulata, 70.

Sullivan tii, 67.

Syriaca, 67.

tomentosa, 68.

tuberosa, 66, 72.

variegata, 68, 69.

verticillata, 71.

vestita, 68.

virgata, 70, 71.

viridis, 66.

viridula, 72. Asclepiodora, 66.

viridis, 66. Astragalus collinus, 51. flavus, 54. Haydenianus, 56. humillimus, 57. Newberryi, 55. * Pattersoni, 55.

\ subcompressus, 56.

Astragalus tricarinatus, 56.

Wardi, 55. Atriplex decumbens, 275.

B.

Benzyl Compounds, Researches on

the Substituted, 209. Benzylbromides, on Certain Sub- stituted, 211.

Metabrombenzylbromide ,214.

Orthobrombenzylbromide, 215.

Parabrombenzyibromide, 211.

Paraclilorbeuzylbromide, 218.

Paraiodbenzylbromide, 219. Biatora carnulenta, 179.

caulophylla, 178.

glauconigrans, 179.

livido-nigricans, 180.

peliaspis, 179.

peliaspistes, 179.

petri, 179. Bigelovia Vaseyi, 58. Biographical notices: —

Karl Ernst Von Baer, 331.

Alexander Braun, 325.

Alexis Caswell, 307.

Charles Davies, 320.

Charles Henry Davis, 313.

Christian Gottfried Ehrenberg,

327.

Nicholas St. John Green, 389. Wilhelm Friedrich Benedict

Hofmeister, 328. Christian Jassen, 329. Fielding Bradfort Meek, 321. Johann Christian Poggendorff,

330. William Augustus Stearns,

291. Emory Washburn, 300. Edward Wigglesworth, 303. Charles Wilkes, 323. Botany, Contributions to, 51, 159,

246. Brickellia Greenei, 58^ Browallia Texana, 16^5. Buellia parasema, 185.

radiata, 173. Butterflies, Sexual Dimorphism m, 150.

Callithamnion arbuscula, 244. Dasyoides, 244.

INDEX.

345

Callithamnion efflorescens, 245.

heteromorplium, 245.

Lejolisea, 244.

Pikeanum, 244.

ptilophora, 244. Canbya and Arctomecon, 51. Canbya Candida, 51. Canotia, 159, 160. Centrostegia, 269.

leptoceras, 269.

Thiu-beri, 269. Chantransia efflorescens, 245. Chlorpea Austin?e, 83. Choudi-us alfinis, 242.

canaliculatus, 242. Chorizantfie, Revision of, 269.

brevicornn, 272.

Bl•e^Yel•i, 270.

Califoniica, 269.

commissuralis, 269.

corrugata, 273.

diffusa, 270.

Douglasii, 270.

fimbriata, 271.

laciuiata, 171.

leptoceras, 269.

membranacea, 270.

Palmeri, 271.

Parryi, 271

perfoliata, 269.

polygonoides, 273.

procumbens, 271, 272.

pungens, 270.

rigida, 273.

staticoides, 271, 272.

stellulata, 270.

Thurberi, 269.

uniaristata, 272.

valida, 271.

"Watsoni, 273.

Wheeleri, 272.

Xanti, 272. Chrysymeuia acanthoclada, 238.

ramosissima, 238. Chthamalia, 74.

biflora, 78.

pubiflora, 77. Claytonia bulbifera, 54. Clethra. 61.

Committees, 281, 285, 287. Communications from Messrs.

A. G. Bell, 1, 283. 285.

T. M. Brewer, 285

J. H. Billiard, 282.

J. P. Cooke, Jr., 113, 124,282, 287, 288.

Communications from Messrs.

D. C. Eaton, 245.

W. G. Faiiow, 235, 287, 288.

W. Gibbs, 288.

A. Gray, 51, 159, 282, 283, 287,

288. W. Harkness, 186, 286. H. B. Hill, 26, 282, 287.

E. R. Hills, 85.

S. W. Holman, 41, 282.

T. S. Hunt, 288.

C. L. Jackson, 209, 211, 282,

286, 287, 288. O. R. Jackson, 36, 282. W. Lowerv, 221, 282, 287. C. F. Mabery, 288. W. H. Melville, 228, 282. A. Michael, 205, 288.

A. J. H. Xorton, 285. T. H. Norton, 205, 288. E. C. Pickering, 284, 286.

B. Peirce, 286, 287.

B. O. Peirce, Jr., 143,287.

C. S. Peirce, 283. J. AV. Powell, 285. W. A. Rogers, 283.

S. H. Scudder, 1.50, 284, 286.

S. P. Sharpies, 11, 98, 284.

A. L. Thomsen, 282.

L. Trouvelot, 284.

J. Trowbridge, 131, 285, 286, 288.

E. Tuckerman, 166.

L. Waldo, 284.

S. Watson, 246, 288.

W. Watson, 282.

J. D. Whitnev, 284.

Dr. Williams!; 285.

C. A. Young, 286. Copper Acetate, Action of Arsenic Trioxide on, 85.

Arsenite of, 11. Corollina pistillaris, 238. Corallorhiza Bigelovii, 275.

Macraei, 276.

striata, 276. Criioria purpurea, 240. Criioriella armorica, 240. Cryptonemia dichotoma, 242.

obovata, 242. Cryptosiphonia Woodii, 241. Cupric Parabromalphatoluate, 225. Cynanchum Carolinense, 76.

discolor, 76.

hirtiim, 76.

obliquum, 76.

/

346

INDEX.

D.

Dasya Callithamnion, 235.

lophoclados, 236.

subsecunda, 235.

ti'ichoclados, 236.

Delessevia Woodii, 238.

Diamido-siilphobeiizide-dicarbonic

Acid, 205. Dimorphism, Sexual, in Butter- flies, 150.

E.

Echidiocarya, 163.

Arizonica, 164.

Californica, 164. Echiiiospermum, 163.

Greeuei, 163. Elaterium Bigelovii, 252.

minimum, 252. Electro-motive forces of Batteries,

Xew Method of Comparing,

137. Epilobium jucnndum, 57. Erioderme velliq'erum, 168. Eriogonum, Revision of, 254.

Abertianum, 258.

acaule, 2-57.

affine, 264.

alatum, 254.

androsaceum, 256.

angulosum, 262.

annuum, 262.

atrorubens, 261.

Baileyi, 268.

brachyiwdum, 259.

brevicaule, 266.

cfespitosum, 256.

cernuum, 259.

chrysocephalum, 263.

ciliatum, 261.

cinereum, 265.

compositum, 257.

corymbosum, 265,

dasyanthemum, 268.

deflexum, 259.

dichotomum, 263.

divaricatum, 262.

Douglasii, 256.

elatum, 264.

ellipticum, 257.

elongatum, 267.

ericajfolium, 265.

Eriogonum, fasciculatum, 265. fiavmu, 255. glandulosum, 261. Gordoni, 261. gracile, 268. Greenei, 83, 263. Greggii, 262. Heermanni, 267. heracleoides, 2.57. hieracifolium, 254. hirtiflorum, 259. incanum, 256. inflatum, 261. intricatum, 269. Jamesii, 255. Kelloggii, 256. Kennedy!, 263. Kingii, 263, 264. lachnogynum, 258. latifolium, 264. Lemmoni, 266. Lobbii, 257. loncho])hy]lum, 266. longifolium, 255. marifolium, 256. Mohavense, 266. microthecnm, 265. multiceps, 264. multiflorum, 262. niveum, 263. nudum, 264. nutans, 259. oblongifolium, 264. ovalifolium, 262. Palmeri, 267. Parryi, 259. parvifo]iunr, 265. pauciflorum, 263. pharnaceoides, 258. I'lumatella, 269. polyanthum, 257. polycladon, 268. proliferum, 263. pusillum, 260. pyrolfefolium, 256. racemosum, 267. reniforme, 260 rotundifolium, 260. salsuginosum, 258. saxatile, 267. scalare, 261. spathulatum, 264. sphaeroceplialum, 257. spergulinum, 258. stellatura, 257. strictum, 263, 267.

INDEX.

347

Eriogonum, siibreniforme, 260.

tenelluni, 2i)\.

Thomasii, 2()().

Thompsona!, 265.

Tlmrberi, 260.

thvinoides, 256.

toiuentosuin, 255.

Torreyauuin, 257.

trichopodum, 260.

triste, 254.

truncatuiu, 266.

unibellatiun, 257.

iindulatuiu, 255.

ursiiiiuii, 256.

villiflorum, 258.

vimineum, 268.

virgatum, 268.

Watsoni, 259.

Wrightii, 266. Evitrichium holoi)terum, 81.

setosum, SO. Erythvocystis Grevillei, 238. Erythroniiim grandiflorum, 278.

purpurascens, 277. Ethers of Uric Acid, on the, 26. Eucheuma acauthocladum, 238.

Farlowia compressa, 241.

crassa, 241. Fellows, Associate, List of, 339. Fellows deceased : —

Alexis Caswell, 285.

Charles Davies, 283.

C. H. Davis, 286.

Nicholas St. John Green, 283.

F. B. Meek, 286.

William A. Stearns, 283.

Edward Wigglesworth, 283.

Charles AVilkes, 286. Fellows elected : —

Henry Larcora Abbott, 280, 283.

Alexander Graham Bell, 286, 287.

Jeremiah Lewis Diman, 286, 287.

William Ferrel, 286, 287.

Richard Saltonstall Greenough, 280.

Thomas Hill, 280.

Nathaniel Holmes, 280.

Bennett Hubbard Xash, 280.

George ^Nlarv Searle, 280, 283.

William Edward Story, 280.

Fellpws, List of, 336.

Filtering, Reverse, the Process and

its Application, 121. Fluorides of ^langanese, Contribu- tions towards the History of, 228. Foreign Honorary Members de- ceased: — Karl Ernst Von Baer, 286. Alexander Brann, 286. Christian Gottfried Ehrenberg,

283, 286. Wilhelm Hofmeister, 286. Christian Lassen, 279, 286. J. C. Poggendorf, 286. Foreign Honorary ^Members elect- ed:— Ernst Cnrtius, 280, 283. Fran9ois August Alexis Mig-

net, 280, 283. James Paget, 285, 287. JNIark Pattison, 280, 283. Henrv Creswick Rawlinson,

280, 283. Arthur Penrhyn Stanley, 280,

283. Alfred Tennyson, 280,284. Eugene Emmanuel Violet-Le- Duc, 280, 283. Foreign Honorary Members, List of,

341. Forestiera acuminata, 63.

Xeomexicana, 63. Fraxinus Greggii, 83. Schiedeana, 63.

Gaillardia spathulata, 59. Galax aphylla, 62. Galaxaura lapidescens, 240. Galium Brandegei, 58. Galvanic Batteries, New Method of comparing the Electro-mo- tive forces of, 137.

New Method of ^Measuring the Resistance of, 137, 140. Gilia brevicula, 79.

csespitosa, 80.

Haydeni, 79.

Parryse, 76. Gomphocarpus, 66, 73.

cordifolius,'73.

purpurascens, 66.

tomentosus, 73.

J

348

INDEX.

Gonolobiis, 74, 75.

Baldwiuianus, 76, 77.

biflorus, 78.

Carolinensis, 76, 77.

cjmanchoides, 78.

granulatus, 75, 76.

hastulatus, 78.

hirsutus, 76, 77.

la?vis, 75.

macrophyllus, 75, 76, 77.

Nuttallii, 76.

obliquus, 76.

parvifolhis, 77, 78.

parvifloi'iis, 79.

pi'oductus, 78.

prostratus, 77, 79.

pubiflorus, 77.

reticulatus, 75.

sagittifolius, 77.

suberosus, 75.

tilifefolius, 76.

viridiflorus, 76. Grateloupia Cutlerite, 243.

Gibbesii, 243. Griffithsia Bornetiana, 243.

corallina, 242.

globifeva, 243.

opuntioides, 243. Gruvelia pusilla, 81. Gymnadeuia longispica, 277, Gymnogongrus GrifRthsiae, 242.

leptopiayllus, 242.

linearis, 242.

tenuis, 242. Gymnolomia Porteri, 59. Gyrophora mammulata, 167.

H.

Habenaria Cooperi, 276.

fcetida, 277.

gracilis, 277.

pedicellata, 276.

Schischmareffiaua, 277.

sparsiflora, 276.

Thiirberi, 276.

Unalashcensis, 277. Halymenia decipiens, 243.

ligulata, 243. Harpagonella Palmeri, 164. Heat, Determination of the Law of Propagation in the Interior of a Solid Body, 143. Hemizonia Streetsii, 162. Holacautha Emovyi, 161.

Horizontal Photoheliograph, The- ory of the, 186.

Hulsea Parry i, 59.

Hydrophylhim appendiculatum, 62.

Hydric Sulphide, on a New Mode of manipulating, 113.

Isopyrum stipitatum, 54.

K.

Kallymenia Californica, 241. Kerguelen Lichens, 181. Kceberlinia spinosa, 161.

Lachnostoma, 74.

hastulatum, 78.

parviflorum, 79.

prostratum, 79.

tigrinum, 74. Laurencia Brongniartii, 237.

gemmifera, 237.

intricata, 237.

spectabilis, 237.

tuberculosa, 237. Lavatera insularis, 249.

venosa, 249. Lecanora ambigens, 176.

dentilabra, 173.

dichroa, 183.

Franciscana, 173.

gelida, 184.

glaucovirens, 172.

Kerguelensis, 184.

orosthea, 173.

semitensis, 172. Lecidea cyrtidia, 181.

mamillana, 180.

psephota, 181.

rubina, 178.

tessellina, 181.

thamnina, 178. Lemmonia, 162.

Californica, 162. Lepidium dictyotum, 54. Leptogium livale, 170.

terrenum, 184. Leptogiossis, 164.

Coulteri, 165.

Texana, 164. Lespedeza angustifolia, 57.

capitata, 57.

INDEX.

349

Lespedeza hirta, 57.

leptostacliya, 57. Liagora Cayohuesonica, 240.

farioiiicolor, 240. Lichens, Kerguelen, 181.

Observation on Xortli Ameri- can and other, 166. Lithothamnion fasciculatum, 239.

polymorphum, 239. Lithothrix Aspergilhim, 236. Lobelia Feayana, 60.

Ludoviciana, 60. Lomentaria saccata, 238. Lupinus Arizonicus, 250.

concinnus, 250.

micranthus, 250.

trifidus, 250. Lychnis, Revision of, 246.

affinis, 247.

Ajanensis, 247.

alpina, 246.

apetala, 247, 248.

Californica, 248.

Drummondii, 248.

elata, 249.

Kingii, 247.

montana, 247.

nuda, 248.

Parryi, 248.

triflora, 247. Lycium gracilipes, 81. Lysimachia angustifolia, 63.

heterophylla, 63.

hybrida, 63.

lanceolata, 63.

longifolia, 63.

quadriflora, 63.

radicans, 63. Lythrum alatum, 251.

breviflorum, 251.

M.

Malvastrum Palmeri, 250.

Manganese, the Fkiorides of, Con- tributions towards the his- toi7,_228.

iMarah Biinima, 2.52.

]\Ielinia angustifolia, 70.

Melobesia amplexifrons, 239. Lenormandi, 239. Lejolisii, 239.

Melotliria pendula, 2.52.

Members, Foreign Honorary, See Foreign Honorary Members.

Mentzelia hirsutissima, 252.

tricuspis, 252. Metastehna angustifolium, 73.

Blodgetti, 73.

parviflorum, 74. Methyllantoin, 31. Methylparaban, 35. Methyluric Acid, 27.

oxydation with nitric acid, 33.

on some of the salts of, 36.

dibaric methylurate, 37.

dipotassic methylurate, 37.

disodic methylurate, 39.

monobaric methylurate, 39.

monocalcic methylurate, 40.

monopotassic methylurate, 37.

monosodic methylurate, 38. Milk Analyses, 98. Mimulus Palmeri, 82. Mirabilis Greenei, 253. Monardella Palmeri, 82.

N.

Nasturtium trachycarpum, 54. Nemacladus longifolius, 60. Nemalion Andersonii, 240.

virens, 240. Nemastoma Californicum, 243. Neuropogon melaxanthus, 183.

Taylori, 183. Nierembergia viseosa, 165. Nitophyllum areolatum, 238.

laceratum, 238.

latissimum, 238.

multilobum, 238.

spectabile, 238, 245.

violaceum, 238.

O.

Observationes Lichenologicse, 166. Officers elected, 281. Q^^nothera Palmeri, 251.

triloba, 251. Omphalaria Kansana, 170. Orthocarpus lasiorhynchus, 82. Orthosia acuminata, 79.

oblongata, 79. Oxytheca inei-mis, 273.

tribolata, 83.

P.

Palafoxia Feaja, 59. Pannaria glaucella, 183.

350

INDEX.

Pannaria placodiopsis, 183.

Sonomensis, 169.

stenophylla, 169.

symptychia, 168.

Taylori, 183. Parabronibeiizyl Compounds, on, 221.

Parabromalphatoluylic Acid, 223.

Parabrombenzylacetate, 222.

Parabrombenzylalcphol, 221.

Parabrombenzylcyanide, 222.

Pai'abrombenzylsulphocyanate, 227.

Triparabrombenzylamine, 22.5. Parnielia fegialita, 166.

coufluens, 166. Pectocarya pusilla, 81.

setosa, 81. Pentstenion coman-heniis, 81.

strictus, 82.

Wardi, 82. Pertusavia albinea, 177.

ambi,g:ens, 176.

colobina, 17.5.

eviglypta, 177.

flavicunda, 176.

thamnoplaca, 175.

velata, 176. Petrocelis cruenta, 239. Peyssonnelia atro-purpurea, 239.

Dubyi, 239.

inibi'icata, 240.

rubra, 239. Phacelia grisea, 80. Philibertia cynanchoides, 64.

elegans, 64.

linearis, 64.

Torreyi, 64.

undulata, 65.

viminalis, 64. Photoheliogi*aph, Theory of the

Horizontal, 186. Phyllophora Clevelandii, 242. Physcia obscura, 167.

picta, 166. Pilopliorus acicularis, 177. Placodium atroalbura, 172.

bicolor, 184.

ferrugineum, 171.

fen'uginosum, 171.

galactophylluni, 171. Plants, Description of Xew Species,

&c., 246. Platanthera fcptida, 277.

gracilis, 277.

Plantanthera striata, 277. Plocamiuni violaceum, 240. Podostigma, 65. Polyotus angustifolius, 72. Polysiphonia dictyurus, 237.

pecten- Veneris, 237. Polysiphonia pennata, 237.

secunda, 236.

senticulosa, 236.

thyrsigera, 237.

vei-ticiHata, 237. Prionotis Andersoniana, 2r42.

Clevelandii, 242. Proceedings, 279. Psoralea Calif ornica, 251. Ptycanthera acuminata, 79.

oblongata, 79. Pyrola, 61'. Pyxine, 166.

coccinea, 167.

Cocoes, 166.

picta, 166.

retirugella, 166.

R.

Reverse Filtering, Process and Ap- plication of, 124. Reyesia, 165.

Rhabdonia ramosissima, 238. Rhododendron Chapmanii, 61.

punctatum, 61. Riceardia INIontagnei, 237. Rinodina mamillana, 174.

milliaria, 175.

ochrotis, 174.

radiata, 173.

thysanota, 174. Rudbeckia Porteri, 59. Rumex longifolius, 254.

occidentalis, 2.53. Rumford Committee, Appropria- . tions, 279, 283.

Monument, 286, 287. Rumford's Works, 279, 283.

S.

Sarcophyllis Californica, 241.

eduiis, 241. Sarcostemnia Brownii, 65.

clausum, 65.

crassifolium, 65.

cynanchoides, 61.

elegans, 64.

INDEX.

351

Sarcostemina hctei'ophyllum, Gi.

iindulatum, 65. Saxifraua elirysautha, 83.

Hirculu.s, 84.

serpvllifolia, 84. Scheele's Green, its Composition,

11. Schizonotus, 06.

puipurascens, 66. SchizyniPnia cocciiiea, 243. Schweiufurt Green, Composition

of, 85. Sexual Diniorphism in Butterflies,

150. Silene Drummondii, 248. SisjTinchium anceps, 277.

belluni, 277.

Bernuidianum, 277.

minus, 277.

mucronatum, 277. Solar Parallax, Application of Horizontal Photoheliooraph to Determination of, 186. Solidago sparsifl<')ra, 58. Sounds, produced electrically, 1, 5. Spiranthes Unalaschcensis, 277. Squamaria lateritia, 184. Stachys Rothrockii, 82. Steironenia, 62.

ciliatum, 63.

florida, 63.

heteropliylla, 63.

lanceolatum, 63.

lonffifolium, 63.

radicans, 63.

revolutum, 63. Stereocaulon cereolinum, 178. Sticta IlalUi, 168.

Sympetaleia, 161.

aurea, 161. Synalissa melamhola, 170.

vii'idi-rufa, 170.

Tfenioma Clevelandii, 236.

macrourum, 236.

perpusillum, 236. Telephone, Researches in, 1. Tetradymia comosa, 60. Thamnosma montana, 160. Thelotrema Californicura, 177. Thelypodium Cooperi, 246. Transits of Venus, Determination of Solar Parallax by, 186.

u.

Umbilicaria Caroliniana, 167.

dictyiza, 167.

mammulata, 167. Urceolina Kergueliensis, 184. Uric Acid, on the Ethers of, 26. Usnea Taylori, 183.

sulphurea, 183.

Vincetoxicum acanthocarpos, 77.

gonocarpos, 76. Viscosity of Air, Effect of Tempera- ture on, 41. Vortex Rings in Liquids, 131.

Cambridge: Presa of Jolin Wilson & Son.

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