in Glass, p. 569. The Leucocytes, p. 569. Spontaneous Generation, p.
570. Successive Polarization of Light, p. 638. A Double Erecting Binoc-
ular, p. 639. Angular Aperture of the Eye, p. 639. Classification of
Microscopic Objects, p. 703. A Life Slide. Illustrated. p. 705. To
Blacken Brass, p. 706. An Optical Experiment, p. 706. Camphor in
Paraffin Lamps, p. 706. Mounting Small Objects in Balsam, p. 707.
Bone Dust in Soap, p. 707. The Fresh Water Polype, p. 707. Repro-
duction of Sponges, p. 707. Multiplication by Budding of Wheel Animal-
cules, p. 708. Spicules of Sponges, p. 709. Fungous Growth in Shells,
p. 776. Advancing Definitions of Objectives, p. 777. Resolution of No-
bert's Band, p. 777. Photo-mechanical Printing, p. 778. The Submersion
Microscope, p. 779. The Micro-pantograph. With cut. p. 779.
ing Tissues in Balsam, 781. Mounting Tissues in Dammar Varnish, p.
781. Logwood Staining Fluid, p. 781. Fungi in Drinking Water, p..781.
Structure of Podura Scales, p. 782. Dry Rot, p. 782.

Mount-

NOTES.- pp. 63, 124, 189, 246, 318, 378, 445, 505, 570, 639, 709, 782.
ANSWERS TO CORRESPONDENTS.- pp. 256, 320, 384, 447, 512, 576, 640.
EXCHANGES. p. 192.

BOOKS RECEIVED. - pp. 128, 256, 320, 384, 448, 512, 576, 640, 720, 784.

ERRATA.

Vol. V.- Page 564, line 22, for rentral read dorsal; line 24. dele and Donacia. Page
565. line 8, for Donacia read Telephorus; line 6 from bottom, for They are read Attelabus
is. Page 566, line 1 from bottom, after while insert Telephorus. Page 745, line 29, for
Raphidophora maculata read Ceuthophilus maculatus; line 31, for Raphidophora subter-
ranea read Hadenæcus cavernarum. Page 746, under cut, for Raphidophora subterranea
read Hadenæcus cavernarum, Page 759, line 18, for Raphidophora read Couthophilus ;
line 23, for R read II ; and for stygia read Ceuthophilus stygius ; line 35, for R. stygia read
Ceuthophilus stygius.

Vol. VI.- Page 45, line 9 from bottom, for TENNIFOLIUM read TENUIFOLIUM. Page 72,
line 10, for Denver 2105 feet above the sea read 5105 feet. Page 136, line 3, for equivalency
read equivalence. Page 138, line 4 of note, for applications read appliances. Page 140,
line 24, for advertency read inadvertency. Page 141, line 3 from bottom, for from read
for. Page 176, head line, for GEOLOGY read ZOOLOGY. Page 178, head line, for ZOOLOGY
read GEOLOGY; line 18, for Chantauqua read Chautauqua. Page 187, line 18, insert S.
before Beale. Page 192, line 4 from bottom, for 321 read 317. Page 237, line 9 from bot-
tom, for Danus read Danaus. Pages 286-289, for Ureila read. Uvella. Page 28%, line 30,
for glauconia read glaucoma. Page 350, line 3, for Leucosticta griseinucha read L. te-
phrocotis. Page 327, place § before last note. Pages 327 and 329, in the last square of
the upper row insert a comma after binocular. Page 374, line 25, for Dongall read Dou-
gall. Page 515, line 15, for W. Doubleday read Mr. Doubleday; last line but one, for
even unite their faces read ever unite their forces. Page 516, line 6, for enclosed read
eciosed line 9, for there read then; line 16, for trace read traces.

139-142.

Five figures of Monads, 286-289 132-138. Seven figures of Ancient

LIST OF CONTRIBUTORS TO VOL. VI.

TO GENERAL ARTICLES.

Dr. CHARLES C. ABBOTT, Trenton, Prof. JAMES ORTON, Poughkeepsie,
N. J.

TO REVIEWS AND BOOK NOTICES.

TO MISCELLANY.

Dr. C. C. Abbott. Trenton, N. J.
Academy of Natural Sciences of Phila
delphia, Penn.

Alexander Agassiz, Cambridge, Mass.
Prof. L. Agassiz, Cambridge, Mass.
J. A. Allen, Cambridge, Mass.
American Philosophical Society, Philadel
phia, Penn.

Prof. J. C. Arthur, Iowa Agricultural Col-
lege.

C. G Atkins, Augusta, Maine.
W. W. Bailey, Providence, R. I.

W. J. Real, Lansing, Mich.

A. W. Bennett, London, England.

Prof. Asa Gray, Cambridge. Mass.
Dr. H. Hagen, Cambridge, Mass.
Prof. S. S. Haldeman, Philadelphia, Penn.
Dr. H. Hartshorne, Philadelphia, Penn.
H. H. Hollenbrush, Reading, Penn.
Prof. Alpheus Hyatt, Salem, Mass.
Prof. D. S. Jordan, Ithaca, N. Y.
H. S. Kedney, Camden, S. C.
Dr. A. Kellogg, San Francisco, Cal.
I. A. Lapham, Milwaukee, Wis.
Prof. J. Leidy, Philadelphia, Penn.
G. Lincecuc, Long Point, Texas.
Rev. Samuel Lockwood, Keyport, N. J.
Prof. O. C. Marsh, New Haven, Ct.

C. E. Bessey, Iowa State Agricultural Col- C. J. Maynard, Ipswich, Mass.
lege.

W. G. Binney, Burlington, N. J.

Prof. T. D. Biscoe, Cincinnati, Ohio.
J. H. Blake, Cambridge, Mass.
Richard Bliss, Jr., Cambridge, Mass.
Wm. Brewster, Cambridge, Mass.
W. B. Brooks, Suspension Bridge, N. Y.
California Academy of Sciences, San Fran-
cisco.

V. T. Chambers, Covington, Ky.
Prof. T. A. Cheney, Leon, N. Y.

Prof. J. W. Chickering, Jr., Washington,
D. C.

N. Coleman, Otsego, Mich.
Prof. A. J. Cook, Lansing, Mich.

Prof. E. D. Cope, Haddonfield, N. J.
Dr. Elliott Cones, U. S. Army.
Dr. Josiah Curtis, Knoxville, Tenn.
W. H. Dall, Alaska.

Ruthven Deane, Cambridge, Mass.

T. W. Deering, Leavenworth, Kansas.
Rev. S. A. L. Drew, South Royalton, Vt.
Dr. B. D. Eastman, Washington, D. C.
Wm. Edwards.

James H. Emerton, Salem, Mass.

Dr. W. G. Farlow, Cambridge, Mass.
Lieut. C. Fitzgerald, British Army.
Dr. Foreman, Baltimore, Md.
S. W. Garman, Minnesota.

Prof. Theo. Gill, Washington, D. C.
Henry Gillman, Detroit, Mich.

Prof. G. Brown Goode, Middletown. Ct.
Rev. E. L. Greene, Greeley, Colorado.

Thomas Meehan, Germantown, Penn.
Lewis Mitchell, Norwich, Ct.

C. II. Nauman, Volusia Co., Florida.
Edward Norton. Farmington, Ct.
Prof. James Orton, Poughkeepsie, N. Y.
Dr. A. S. Packard, Jr., Salem, Mass,
Prof. H. W. Parker, Amherst, Mass.
Prof. G. H. Perkins, Burlington, Vt.
F. W. Putnam, Salem, Mass.
Robert Ridgway, Washington, D. C.
Prof. C. V. Riley, St. Louis, Mo.
S. II. Scudder. Mentone, France.
Prof. N. S. Shaler, Cambridge, Mass.
Dr. H. L. Smith, New York.

J. Edward Smith, Ashtabula, Ohio.
Smithsonian Institution. Washington, D. C.
Charles J. Sprague, Boston, Mass.
R. E. C. Stearns, San Francisco, Cal.
Dr. Wm. Stimpson, Chicago, Ill.
Charles Stodder, Boston, Mass.
Prof. J. Sullivant, Columbus, Ohio.
D. J. Tapley, Danvers, Mass.
Prof. S. Tenney, Williamstown, Mass.
Robert B. Tollès, Boston, Mass.
T. Martin Trippe, Orange, N. J.
Dr. R. H. Ward, Troy, N. Y.
Prof. B. G. Wilder, Ithaca, N. Y.
H. Willey, New Bedford, Mass.
Dr. Wm. Wood, East Wind-or Hill, Ct.
Dr. J. J. Woodward, U. S. A. Med. Mus.
Prof. J. Wyman, Cambridge, Mass.
Dr. H. C. Yarrow, Cambridge, Mass.

Academy, London.

COPIED FROM.

American Journal of Science and Arts, New
Haven.

Annals and Magazine of Natural History,
London.

Bulletin of the Esser Institute, Salem.
College Courant, New Haven.

English Mechanic and World of Science,
London.

Entomologist's Monthly Magazine, London.
Journal of the Anthropological Institute,
New York.

Journal of Botany, London.

Journal of the Queckett Club, London.
Land and Water, London.
Manchester Guardian, Manchester, Eng.
Medical Record, New York.

Monthly Microscopical Journal, London.
Nature, London.

Pall Mall Budget, London.

Quarterly Journal of Microscopical Science,
London.

Report of State Entomologist of Missouri
for 1872, St. Louis.
Revue Scientifique.
Science Gossip, London.

Journal of Franklin Institute, Philadel- Siebold and Kölliker's Zeitschrift.

phia.

Spener'sche Zeitung, Berlin.

MY DEAR FRIEND:-On the point of starting for the Deep-Sea Dredging expedition, for which you have so fully provided, and which I trust may prove to be one of the best rewards for your devotion to the interests of the Coast Survey, I am desirous to leave in your hands a document which may be very compromising for me, but which I nevertheless am determined to write in the hope of showing within what limits natural history has advanced toward that point of maturity when science may anticipate the discovery of facts.

If there is, as I believe to be the case, a plan according to which the affinities among animals and the order of their succession in time were determined from the beginning, and if that plan is reflected in the mode of growth, and in the geographical distribution of all living beings; or, in other words, if this world of ours is the work of intelligence, and not merely the product of force and matter, the human mind, as a part of the whole, should so chime with it, that, from what is known, it may reach the unknown; and if this be so the amount of information thus far gathered should, within the limits of errors which the imperfection of our knowledge renders unavoidable, be sufficient to foretell what

*Communicated by Prof. Peirce from advance sheets of Bulletin of the Museum of Comparative Zoology. No. 3. A Letter concerning Deep-Sea Dredgings, addressed to Professor Benjamin Peirce, Superintendent United States Coast Survey, by Louis Agassiz. Cambridge, Mass., December 2, 1871.

Entered according to Act of Congress, in the year 1872, by the PEABODY ACADEMY OF SCIENCE, in the Office of the Librarian of Congress, at Washington.

AMER. NATURALIST, VOL. VI.

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