LIBRARY OF I685_IQ56 m')^^^^st2^£Mmijmsi^ws PROCEEDINGS Iowa Academy of Sciences I^OF^ 18Q8, VOLUME VI. EDITED BY THE SECRETARY. PUBLISHED BY THE STATE. DES MOINES: F. B. CONAWAY. STATE PRINTER. 1899. LETTER OP TRANSMITTAL. Des Moines, Iowa, December 31, 1898. To His Excelleiic]!, Leslie M. Shaic, Governor of loira: Sir — In accordance with the provisions of title 2, chapter 5, section 136, code 1897. I have the honor to transinit herewith the proceedings of the thirteenth annual session of the Iowa Academy of Sciences. With great respect, your obedient servant, H. Foster Bain, Secrefartj Joirtt Acodeiinj of Sciences. OFFICERS OF THE ACADEMY. 1H98. President.— T. H. Macbride. First Vice-President. — B. Fink. ISecond Vice-President. — M. F. Arey. Secretary-Treasurer. — Herbert Osborn. Librarian.— H. Foster Bain. EXECUTIVE committee. Ex-Ojficio.—T. H. Macbride, B. Fink, M. F. Arey, Herbert Osborn. Elective.— S. W. Beyer, A. C. Page, W. H. Norton. 1899. President. — W. S. Hendrixson. First Vice-President. — M. F. Arey. Second Vice-President.— F. M. Witter. Secretary-Treasurer.— 'S.. Foster Bain, executive committee. Ex-Officio.—W . S. Hendrixson, M. F. Arey, F. M. Witter, H. F. Bain. Electire.S. W. Beyer, A. C. Page, W. H. Norton. PAST PRESIDENTS. OsBORN, Herbert 1887-88 Todd, J. E 1888-89 Witter, F. M 1889-90 Nutting, C. C 1890-92 Pammel, L. H 1893 Andrews, L. W 1894 NoRRis, H. W 1895 Hall, T. P 1896 Franklin, W. S 1897 Macbride, T. H 1897-98 Hendrixson, W. S 1898 MEMBERSHIP OF THE ACADEMY. FELLOWS. Almy, F. F Iowa College, Grinnell Andrews, L. W State University, Iowa City Arey, M. F State Normal School, Cedar Falls Bain, H. F Geological Survey, Des Moines Barris, W. H Griswold College, Davenport Bates, CO Coe College, Cedar Rapids Beach, Alice M State College, Ames Beardshear, W. M State College, Ames Bennett, A A State College, Ames Beyer, S. W State College, Ames Blakeslee, T. M Des Moines College, Des Moines Calvin, S State University, Boulder, Colo . Chappel, George M State Weather Service, Des Moines Clark, Dr. J. Fred Fairfield Combs, Robert State College, Ames Conrad, A. H Parsons College, Fairfield Cratty, R. I Armstrong Curtis, C. E' State College, Ames Davis, Floyd Des Moines Ende, C. L Burlington Fink, B Upper Iowa University, Fayette Fitzpatrick, T. J Lamoni Frederick, C. a State Normal, Cedar Falls Fultz, F. M Burlington Hadden, David E Alta, Iowa Hendrixson, W. S Iowa College, Grinnell Holway, E. W. D Decorah HOUSER, G. L State University. Iowa City Kelly, H. M Mt. Vernon Keyes, C. R Des Moines Leverett, Frank U. S. Geological Survey, Denmark Marston, a State College, Ames Macbride, T. H State University, Iowa City Newton, G. W Cedar Falls NiLES, W. B State College. Ames 8 IOWA ACADEMY OF SCIENCES. NORRIS, W. H Iowa College, Grinnell Norton, W. H Cornell College, Mt. Vernon Nutting, C. C State University, Iowa City O'DONOGHUE, J. H Storm Lake Page, A. C State Normal, Cedar Falls Pammel, L. H State College, Ames Reppert, F Muscatine RiCKER, Maurice Burlington Ross, L. S Drake University, Des Moines Sage, J, R State Weather Service, Des Moines Savage, T, E Iowa City SCHLABACH, Carl High School, Clinton Shimek, B State University, Iowa City Stanton, E. W State College, Ames Stookey, Stephen W Coe College, Cedar Rapids Summers, H. E State College. Ames Tilton, J. L Simpson College, Indianola Veblen, a. a .State University, Iowa City Walker, Percy H State University, Iowa City Weems, J. B State College, Ames WiCKHAM, H. F State University, Iowa City Witter, F. M Muscatine Youtz, L. a Simpson College, Indianola ASSOCIATE members. Adams, P. E Durham Baldwin, F. H Tabor Barnes, William D Blue Grass Biering, Dr. Walter Iowa City Bond, D. K Rockwell City BOUSKA, F. W Ames Brainard, J. M Boone Brown, Eugene Mason City Cameron, J. E Cedar Rapids Carter, Charles Corydon COBURN, Gertrude State College, Ames Crawford, Dr. G. E Cedar Rapids Deyoe, a. M Britt ECKLES, C. H State College, Ames Finch. G. E West Union Gifford, E. H ; Oskaloosa Gow, James E Greenfield Hill, Dr. Gershom H Independence Hume, H. H Ames Jenkins, P. W Simpson College, Indianola Johnson, F. W Grinnell Lenocher, F. E Panora Livingston, Dr. H Hopkinton Miller, G. P Des Moines Miller, A. A Davenport Mortland, J. a Cedar Falls IOWA ACADEMY OF SCIENCES. 9 Mueller, Herman Iowa City Myers, P. C Iowa City Newell, Wilmon State College, Ames OSBORN, B. F Rippey Paddock, A. Estella Whitten Peck, Morton E Iowa Falls Reed, CD Ames RiGGS, C. B Rockwell City RODWELL, W. W Marshalltown Rolfs, J. A Le Claire Sample, A. F Lebnon SCHULTE, J. I Ames Stewart, Helen W Des Moines VOLDENG, Dr N. M -- Des Moines Walker, L. R Oelwein Walters, C. W Cedar Falls Weaver, C. B Denver, Colorado Williams, I. A Manly CORRESPONDING MEMBERS. Arthur, J. C Perdue University, Lafayette, Indiana Ball, C. R Missouri Botanical Garden, St. Louis Ball, E. D Agricultural College, Ft. Collins, Colorado Barbour, E. H State University, Lincoln, Nebraska Bartsch, Paul Smithsonian Institution, Washington, D. C. Beach, S. A Geneva, New York Bessey, C. E State University, Lincoln, Nebraska Bruner, H. L Irvington. Indiana Call, R. E Carver, G. W Tuskegee. Alabama COLTON, G. H Virginia City, Montana Crozier, a. a Ann Arbor, Michigan Drew, Oilman C Johns Hopkins University, Baltimore, Md. Franklin, W. S South Bethlehem, Pennsylvania Gillette, C. P Agricultural College, Fort Collins, Colorado GOSSARD, H. A Lake City, Florida Hall, T. P Kansas City University, Kansas City, Mo. Halsted, B. D New Brunswick, New Jersey Hansen, N. E Brookings, South Dakota Hansen, Mrs. N. E Brookings, South Dakota Haworth, Erasmus State University, Lawrence, Kansas Heileman, W. H Pullman, Washington Hitchcock, A. S Agricultural College, Manhattan, Kansas Jameson, CD Leonard, A. G Oberlin, Ohio Mally, C W Wooster, Ohio Mally, F. W Hulen, Texas McGee, W. J Bureau of Ethnology, Washington, D. C. Meek, S. E Field Columbian Museum, Chicago, Illinois Mills, S. J Denver, Colo. IQ IOWA ACADEMY OF SCIENCES. OSBORN Herbert State University, Columbus, Ohio Owens, Eliza Bozeman, Montana Parker, H. W. .' New York City, New York Patrick, E, G Department Agriculture, Washington, D. C Rolfs, P. H Lake City, Florida SiRRiNE F. A Jamaica, New York Sirrine, Emma Woodstock, Illinois Spencer, A. C U.S. Geological Survey, Washington, D. C. Stewart, F. C Ithaca, New York Todd, J. E State University, Vermillion, South Dakota WiNSLOW. Arthur Kansas City, Missouri PROCEEDINGS THIRTEENTH ANNUAL SESSION IOWA ACADEMY OF SCIENCES. The thirteenth annual session of the Iowa Academy of Sciences was held in the geological rooms at the capitol build- ing in Des Moines, December 27 and 28, 1898, In business ses- sions the following matters of general interest were passed upon. REPORT OF THE SECRETARY-TREASURER. To the Members of the Iowa Academy of Sciences : The Academy has, during the past year, had a very satis- factory growth in the addition of sixteen associate members. The proceedings include 248 pages, presenting an interesting array of matter both instructive and useful. The appearance of the proceedings was delayed longer than usual on account of the legislative printing. Several papers presented were nec- essarily omitted on account of reaching our limit allowed for the volume. 12 IOWA ACADEMY OF SCIENCES. The new code, by the omission of the words "with necessary illustrations, " was construed by the executive council as not permitting the payment of bills for the engraving of plates and the account of the Star Engraving Co. for such work is unpaid, and I would suggest that authority be given for settlement from Academy funds. Part of the plates have already been provided for by the authors and possibly some others can be, so as to reduce the total necessary to pay from Academy funds. It will also be desirable to secure a change in the present wording of the law so as to permit illustration in future. First notices only of dues were sent to members and there are quite a number who have not paid dues for past year, so that the funds in the treasury will be considerably augmented with the collection of these with the dues for coming year. It is with great sorrow that I record the death of one of our most distinguished members, Dr. C. A. Schaeffer, who had been for a number of years associated with us. While his numerous duties prevented his contributing to our proceedings, he was always most cordial and hearty in his support and encourage- ment of our work. I also regret to announce the death of Mr. E. H. Lonsdale, one of our former fellows, recently engaged in the topographic work of the United States Geological Sur- vey. Mr. Lonsdale contributed to volumes I and II of the Academy proceedings and was, while in Iowa, an active mem- ber. While Dr. James Hall, of New York, left Iowa some years before the organization of the Academy, his much regretted death is of more than passing moment to us. Dr. Hall was one of the scientists who earliest worked in Iowa, and we are yet deriving the benefit of his pioneer labors. It is with peculiar regret that I contemplate this as my final report for, notwithstanding the effort sometimes necessary to fulfill the duties of the office, it has been a positive pleasure to me to give such time as was possible to the work and to watch the growth of the organization. May its prosperity and use- fulness increase many fold in the years to come. FINANCIAL, STATEMENT. Accounts and vouchers submitted herewith show receipts of $140. 3(5 and expenditures of $71.84, leaving a balance on hand of $68.52. IOWA ACADEMY OF SCIENCES. 13 SUMMARY OF RECEIPTS AND EXPENDITURES. Receipts Balance from la-^t year $ 77.06 Annual dues from members _. 45 00 Pees from associate members 16.00 Sales of Proceeding-s 2 30 Total $140.36 Expenditures Express and freight $ 3 91 Reprints of authors' extras 32.00 Printing- prog'rams, blanks, etc 33.00 Postag-e on notices, collections, etc 2.56 Miscellaneous expense 37 Total $ 71.84 Balance , 68 52 $140.36 Respectfully submitted, Herbert Osborn. The committee appointed to examine the treasurer's accounts reported as follows : The accounts and vouchers of the treasurer of the Academy have been examined- and found to be correct. A. C. Page, P. C. Myers, Commiltee. The Academy established the following rule regarding illustrations; Where the illustrations for any single article do not cost more than $2.50 the amount shall be charged to the Academy funds; where the cost is between $2.50 and $10 the cost beyond $2.50 shall be assessed half against the Academy and half against the author ; where the cost is more than $10 all such excess shall be charged to the author. The following amendments of the constitution were proposed and will be voted on at the next annual meeting: Section iv to be amended by the substitution of the word '• treasurer " where the word "secretary-treasurer" is used. Section v (a) to be amended by the substitution of the words "a secre- tary and a treasurer" where the words "a secretary-treasurer" are used Section viii to be amended by the substitution of the word " secretary " for the words "secretary- treasurer " as there used. Section ix to be amended by the substitution of the word "secretary" for the words " secretary-treasurer " as there used. Proposed by n. F. Bain. The following fellows and members were elected: fellows. T. M. Blakslee, Des Moines, professor of mathematics. State University. Boulder, Colo., former member; Dr. J. Fred Clark, surgeon 49th Iowa Vol- unteers, former member; C. A. Frederick, Cedar Falls, assistant professor 14 IOWA ACADEMY OF SCIENCES. of physics, Iowa State Normal; David E. Hadden, Alta, astronomer; J. H. O'Donoghue, Storm Lake, superintendent schools: T. E. Savage, Iowa City, assistant in botany, State University, former member; H. E Summers, Ames, professor of zoology, State College of Agriculture; H. F. Wickham, Iowa City, assistant professor of zoology, State University. MEMBERS. p. E. Adams, Durham; Dr. Walter Bierring, Iowa City; D. K. Bond, Rockwell City: F. W. Bouska, Ames; James E. Gow, Greenfield; H. H. Hume, Ames; P. W. Jenkins, Indianola: F. E. Lenocher, Panora; Her- man Mueller, Iowa City: A. Estella Paddock, Whitten; A. F. Sample, Ames; D. H. Talbot, Sioux City; L. R. Walker, Clermont: Ira A.. Williams, Ames. The secretary was instructed to let each author see his own proof so far as might be possible. The following officers were elected for 1899 : President— W . S. Hendrixson. First Mce- President— M.. P. Arey. ISecovd Vice-Presidtnt—F. M Witter. Secretary- Treu surer — H. F. Bain. Elective Members of the Executive Council— S. W. Beyer, W. H. Norton, A. C Page. In general sessions the following papers were read in full or by title: *Herbert Osborn— Observations on Hemiptera. ** J. H. O'Donoghue- Gas Analysis. **Launcelot W. ANDREWS— On a New Method for the Quantitative Determination of the Water Present in Concentrated Sulphuric Acid. * Maurice RrCKER— The August Cloud-burst in Des Moines County. ** N. M. VOLDENG— Cell-formation and Cell-life. * L. S. Ross— A Simple Incubator. *.IAMES E. Gow— Forest Trees of Adair County. * James E. Gow— Effect of Sleet Storm. * Francis M. Fultz— The Burlington Artesian Well. *C. C. Nutting— The Colors of Deep-sea Animals. *P. M. Witter — Observations on the Geology of Steamboat Springs, Colorado. I Charles R. Keyes— Cuesta Topography of the Crimean Peninsula. J Charles R. Keyes— Permian Series of Eastern Russia. * Charles R. Keyes— Some Physical Aspects of General Geological Cor- relation. * S W. Beyer — Buried Loess at Ames, Iowa. *** H. Foster Bain— Notes on the Drift of Northwestern Iowa. The extra- morainic drift of Northwestern Iowa has many peculiar characteris- tics and its age is in doubt. It has been provisionally correlated with the lowan, but this seems now quite certainly wrong. There is an anomalous phase of the Kansan, as well as typical drift of that formation, in the region, and this has contributed to the confusion. The conditions governing the development of ferretto are discussed. * Frank Leverett— The Lower;;Rapids of the Mississippi River. ♦Published in this volume. **Read by title. No copy furnished for publication. ** Published In the American Geologist. ?Read by title. Abstract furnished. IOWA ACADEMY OF SCIENCES. 15 t J. A. Udden— The Sweetland Creek Beds. These consist of some thin basal layers of blue arenaceous dolomite, overlaid by blue and black shale. They rest unconformably on the Cedar Valley limestone in places in Muscatine county, and are overlaid uncomformably by the coal-measures. Greatest observed thickness is 40 feet. The fossils are Pychodus and Rhynchodus remains, a few Lingulus and Spathio- caris emersoni Clarke, indicating- that the formation belong's to the upper Devonian. * J. A. Udden— The Pine Creek Conglomerate. * J. A Udden — Diatomaceous Earth in Muscatine County. *.J. E. Todd— New Light on the Drift of South Dakota. * B. Shimek— The Distribution of Loess Fossils. * B. SHTMf K — The Iowa, Liverworts. A preliminary anotated list of Hepa- ticce found in Iowa. ** J. Fred Clark— The Agency of Flies in the Spread of Disease, (a.) Literature on the Subject (b. ) Experimental Proof of Possibility of Flies Carrying Germs of Typhoid Fever, (c ) Evidence From Observations at the Seventh Army Corps Camp of 1898. *H. E. Summers — A Generic Synopsis of Nearctic Pentatomidce. *T. E Savage —A Preliminary List of the Mosses of Iowa. *T. J. AND M. F. L. FjTZPATRICK— Flora of Southern Iowa. Three trips made overland in a van the last season Large collections were obtained; notes written. The region surveyed being the two southern tiers of counties, from Decatur county westward to the Missouri River, a region of the state of which but little is known botanically. Quite a list of rare species and several species not before reported. § B. Fink— Additions to the Bibliography of North American Lichens. I C. R. Ball,— The Genus Salix in Iowa. I E D. Ball— A Review of the Cercopida? of N. A. north of Mexico. *P. C. Myers— Preliminary Report on the Diatoms of Iowa. (1.) General distribution. (2 ) Interesting localities. (3.) Diatomaceous depos- its. (4.) Geographical distribution. (5.) Variation and prob- able cause. JT P. Ball— Extension of the Complex Algebra of the Plane to Three- fold Space. *P. C. Myebs— Report on a Fossil Diatomaceous Deposit in Muscatine County, Iowa. (1 ) List of species with general distribution and habitat of each. (2 ) Probable conditions existing at the time the bed was formed. **Geo. W. Carver- Observations on Some Iowa Fungi. ** Gilbert L. Houser— The F^'hysical Basis of Nervous Activity. The ultimate structure demonstrable in nerve cells; a review of methods of investigation; the changes which occur in nerve cells as the result of their activity; conclusions as to the seat of nervous energy and its mode of liberation. * Published in tliis volume. **Rea(l by title. No copy furnished for publication. + Published in the Journal of Geology. 1: Read by title. Abstract furnished. § Read by title. Copy arriving- after meeting. 16 IOWA ACADEMY OF SCIENCES. PRESIDENTIAL ADDRESS. THE ACADEMY AND THE PEOPLE. BY PROF. T. H. MACBRIDE OF THE STATE UNIVERSITY. Gentlemen of the Academy: Again, by the decrees of fortune, I appear before you as your presiding officer to extend to you the felicitations of the season and to congratulate you on this, our annual reunion. It is a fortunate thing that so many men can thus come up each from his own field, here to meet in friendly converse with his friend of like pursuit, of like employment, each to derive encouragement and stimulus for further and happier endeavor. This evening there are many reasons for special congratula- tion. Our roll of fellows and members is longer than ever before; our program shows a more general and widespread interest; every department of scientific work in the state would seem to be more assiduously cultivated than has hitherto been the case. Let us hope that the enthusiasm which has thus far marked the progress of the Academy, and especially distinguishes the present session, may continue until every man of science in the state shall appreciate and feel its uplifting power. We ought to fill the largest hall in this city, and the time approaches when we shall. It seems less necessary to enumerate here a list of the papers and publications of our membership during the year that is gone. Many of the more important are before you in the latest volume of our printed proceedings. Suffice it to say our members and fellows have not been idle. Some have been honored, and in their honors we rejoice to share, by transfer to wider fields and opportunities new, in other and distant states. Our worthy secretary. Professor Osborn, to whose enthus- iastic effort, more than to any other one thing the success of the Academy during these recent years is due, has already for IOWA ACADEMY OF SCIENCES. 17 some months occupied the chair of zoology in the University of Ohio; Professor Hall occupies the chair of mathematics in the University of Kansas City: others are in still more distant states; one whose name is on our program is with the army of occupation in Cuba; and one, be it softly spoken, as is fit- ting, has gone on to his reward eternal. The sods of this, his newly adopted state, rest lightly yet above his fresh made grave. Charles Ashmead Shaeffer died September 23d. It is most proper that in the midst of our felicitations, in the glad- ness of our reunion, we should for a moment pause to lay upon that grave the wreath of grateful memory. Though, by his unceasing labors for the institution he so nobly served, he was in large measure deterred from actual participation in the work of this Academy as such, nevertheless, we always knew we had in him a sympathetic friend, and his constant attend- ance at our sessions was an inspiration to us all. Dearest to those who knew him best, the members of this Academy will mourn his untimely departure and grieve over their irreparable loss. The report of the secretary and treasurer shows that the finances of the Academy are in satisfactory condition. Indeed, since the state has assumed the cost of publishing our proceed- ings, our expenses as a society are limited largely to the out- lay incident to our sessions; printing, postage and matters of an incidental nature. However, the result is that while not a royal society, not under the patronage of the king nor of any- body in particular, we are, nevertheless, as suggested here last year, not quite independent; we are under obligation; we are in a sense bounden to the people of Iowa and it has seemed to me that it might be worth while for us to consider for a little time this evening the kind and amount of return which the people of the state may reasonably expect for their investment. In the first place, the very existence and activity of such a body as this Academy is a factor of no small moment in the intellectual life of the community. Great universities in some parts of the world may exist, glow along for centuries, side by side with the greatest penury, superstition and intellectual night; within a mile of the University of Bonn I have seen a man ploughing with the family cow, while his wife and chil- dren, hard by, made hand-made brick in the open field. But such a situation fortunately is not possible, we may believe, in 18 IOWA ACADKMY OF SCIENCES. America among our more active people The influence of a great intellectual center is not limited to the roster of its organization. The University of Michigan has educated the whole northwest, has influenced you and me, though we may never have seen its stately halls. And so I take it with an Academy like this; its work is far-reaching as the state among our own people, and far-reaching as science among the nations of the world; this by mere virtue of its existence, and all apart and distinct from the work it has been able to accomplish. The spectacle presented year by year of from three to four score, or more, intelligent men assembling at their own cost to discuss themes which offer no pecuniary returns, present or prospective, is at least sufficiently significant in this mercenary age of ours to demand attention. But there is something more. The problems we here discuss escape at length these halls, reach the public press, the firesides of the common people, and then who shall estimate the wide influ- ence of the Academy as a constant impulse to intellectual life, more and more manifest and in every way most potent. Every discovery made by any member of this Academy, every new list of plants, every new bed of clay, every planed pebble or fossil tooth, every public discussion of printed report, stirs as nothing else the intellectual life of the community where such discovery appears or is reported, and redeems such segment of our population, in so far, from that fearful stagnation into which, apart from such stirring, humanity is so prone to fall. Our present popular and highly successful geological survey reaching as it does one after the other, in a most efficient way, every county in the state, is doing a wonderful work in the direction indicated, and I believe it is not too much to say that that survey is in a large measure due to the suggestion and organized effort of this Academy. At any rate, the survey is but carrying out in a more methodic and systematic way the work which has constantly largely engaged us here. It is well for us thoroughly to understand this matter and betimes to put it clearly before the world. There are, as all history testifies, but two possible attitudes of the human mind; the one responsive to the stimulus of the external world, an attitude of inquiry, effort, search after truth with consequent ennobling glorious progress; the other an attitude of resigna- tion, inactivity, a study of death rather than life, with result- ant torpor, dry rot, necrosis of every noble power. If the IOWA ACADEMY OP SCIENCES. 19 attitude of Americans thus far has been the former, the cause is not far to seek. The opening up and exploitation of a new continent has up to this time kept our people alive as have been no people elsewhere on the face of the earth, perhaps in all historic time; but that particular form of stimulus is pass- ing. We are fast settling into conditions which are paralleled by the older nations of the world; I may not detail them here, but we all know that the stimulus of natural newness is pass- ing, and I need not tell this audience that in the organized efforts of scientific men, in academies and royal societies, lies the only hope of the promethean fire. Such institutions are the open court of intellectual progress, the focus of inventive life. They, and they alone, foster and feed the inventive spark that shall at length blaze in the open field of discovery. Literature is glorious; but on occasion she hides in cloisters for a thousand years, while outside her gates all the world may slumber; art is wonderful; but art, too, is hemmed in by narrow, self-determined limits; philosophy is reflective, and is wont to lose herself in some far off Nirvana; it remains for science, for science only, to find for the human mind employ unceasing in duration, unlimited in scope, far- reaching in inquiry, beneficent in its purpose, touching with blessing the king in his palace, the poor man in his home, the savage in his hovel. Literature has no new themes. She still seeks her models in the millennia of the past, and turns the kaleidoscope worn by the service of three thousand years; phi- losophy attempts to reason upon data confessedly uncertain, and accordingly from century to century makes little progress ; science alone finds problems forever new, bases her conclus- ions upon facts subject to constant verification, so that in an academy such as this there is perpetual reminder that the bounds of human knowledge are widening, and are yet to be enlarged. In no college, in no university, however well organized, do we attain the same result. In a university every phase of human learning has its appropriate place and receives equal consideration; here the scientific method has full sway, naught enters to distract or to disturb, and in the light of friendly criticism each finds the help and encouragement of the other in the sifting of truth or the proclaiming of fact already ascertained. In the second place, an academy such as ours is of highest 20 IOWA ACADEMY OF SCIENCES. service to the state, in the fact that it is a perpetual protest against false science, science falsely so-called, insanity and nonsense of every description, into v^rhich civilized people are apparently so easily and constantly led astray. I think that I speak with the approval of most students when I say that the common people stand to-day more in need of our methods than of our facts. The habit of trusting only to accurate and oft repeated observation, the habit of correlating fact with fact, the habit of appealing constantly to some independent check, or verification, of accepting nothing that does not pass the ordeal of such scrutiny and test, such habit, if it could be imparted to our people now, and once for all, would certainly be of more value to them by far than all the facts we are likely to set before them for many a decade. The credulity, the absolutely infantile credulity, of some of our most intelligent people surpasses belief. The fact that "truth lies at the bottom of a well," that its attainment is difficult in the extreme, never occurs to most men, apparently, at all The song of the veriest charlatan meets readier credence than the voice of the labor- ious student. Accordingly one craze, or form of infatuation after another, sweeps over enlightened humanity. Forty years ago it was spiritism or spiritualism; to-day it is Christian Science. I leave the Christian apologist to disown the first portion of the binomial or not, as it may seem to him good; but I for one protest against the use of the word science in any such connection. Surely science has been long enough in the world to stand for something real in court, to possess a charac- ter and a reputation that has standing; surely science is entitled, once for all, to be relieved from the imputations of modern superstition and self delusion. The one thing for which the man of science strives is the ascertainment of facts, as these are appreciable by the senses aided by all instruments of precision; the one thing that so-called Christian Science denies, and all the while refuses, is what the senses of man declare to be a fact. There can by no possibility be science here where truth is studiously excluded and yet thousands of Americans, possibly hundreds of lowans, are to-day inclined to spend their money and their time in pursuit of this latest delusion in the mirage book of time. Of course I shall not be accused of refusing to my suffering fellow-man any form of solace which humanity, individually or collectively, may possibly bring to aid him; but let us have no IOWA ACADEMY OF SCIENCES. 21 confusion; let us call things by their right names. Let mental, nervous and all sorts of more or less imaginary ailments be treated as the symptoms indicate; let effect be linked to appro- priate cause as elsewhere in physiological research, and scien- tific methods may, at length, discover all attainable truth; but, let no man, forgetful of every principle of scientific procedure, and oblivious to its very first requirements, heaping up rub- bish from the deservedly forgotten idealistic philosophj^ of the middle ages, go forth in the name of science to proclaim that there is no pain; that there is no disease; that there is no bodily ill; that "all, all is mind! " Science knows him not! That such delusions find lodging among most excellent people, in no wise affects the case. The remedy lies, I shall still maintain, in the inculcation of real science which insists on the ascertainment of truth, and especially in the application of the method of science which trusts the evidence of the senses acting in their normal province and in a natural way. But is it not astonishing that almost every ancient delusion that aims nowadays to lift its head among enlightened men assumes to speak in the name of science, thus unwittingly pay- ing tribute to the reputation which the scientific movement has made for itself in the world? Thus we have "occult science," strange contradiction of terms! and "esoteric science" and "mystic science " and "monistic sciense," "spiritualistic science," " theosophic science, " and I know not what. Surely science has difficulties and perplexities of its own to deal with, sutticient that it may be allowed to protest against the imposi- tion of such a burden of unheard-of accumulated rubbish. I repeat; the only remedy for false science is true science; the only knowledge that will save people from the constant recur- rence of dominant superstition is found in that form of human knowledge and activity which this academy is set to foster. Literature will not do it; art will not do it; even raligion, divine though her mission be, will not do it; has not done it. Her gospel seems to assume the spread of another gospel, that of common sense, and the gospel of common sense is modern science. If our people could once get into the way of looking at things as they really are, and judging the natural world on the principles of simple, clear-eyed, common sense, wisdom would at last be justified of her children. But there is still another phase of the situation which I think ought to be mentioned here to-night. There is to-day, at 22 IOWA ACADEMY OF SCIENCES. the end of the century, in the intellectual world everywhere, plainly a reaction against the distinctly scientific method of acting and doing. Thirty years ago, twenty- five years ago, science seemed about to sweep everything before it. Every phase of human thought was roused in a second renaissance, more far-reaching, and, as I think the future historian will declare, immensely more pregnant of result than was that earlier revival of the sixteenth century. But thirty years have passed and now the trend is different The freshness of the impulse is to most of us a memory; the world of thought has begun again to crystallize and although the force of that first upheaval is by no means spent, shores and continental outlines are all different from what they were before, nevertheless old tendencies, old ideas, old superstitions even, as just noted, are beginning again to lift their heads. The scientific movement as represented by this Academy is at an ebb and we must recognize the fact. Now the reason for this condition is perfectly plain. In the first place, it is in fact a reaction. The generations of men have had time to shift once on the face of the earth. Men are lovers of ease. Science is aggressive. Under the reign of science the world is forever on the qui rive. Men are almost afraid to open their morning papers lest during the night science may have abrogated the necessity for food, written an analysis of love, or have so far confined to wires and rods the electricity of the planet that none shall be left for thunder- storms or auroral displays. The human mind cannot be always tense. The best lecture at last puts the auditors to sleep. This will account for any popular declension. Then again, there are hundreds of educated men whose conservative sympathies are all with the older views, to whom the real sig- nificance and purport of the scientific movement are but dimly seen. Not studying science itself, but only a presentation of it — I do not say misrepresentation of it — or turning from true scientific employ to the more fascinating fields of speculation, they make of science no more than a system of philosophy, comparable to any other one of the varied schemes of human dreamings that drift hither from the hoar antiquity of the race. It is thus that Mr. A. T. Balfour in his "Foundations of Belief" and Professor Haeckel in his "Confessions" meet in their assault on the methods of science, though separated by the whole diameter of the earth in the paths of their argumen- tation. IOWA ACADEMY OF SCIENCES. 28 May I venture to suggest that the right honorable author, not being expert in the simple phases of scientific effort, has misconceived the mission and meaning of science altogether. He says of science, "Foundations of Belief, " p. 94: "Its busi- ness is to provide us with a theory of nature." Never in the world! Its business is to depict nature as we find her and to give such account as may be possible of agencies which effect her changes. Science offers no explanation of nature. The man of science may frame hypotheses, but they are only as instruments of research for his own convenience, to be used and cast away when their purpose is attained, or when better are at hand. The facts attained by science, the methods of discovering truth would remain precisely what they are, whether our theory of nature be that of the eternity of a self- created universe, whether that of the old-time theologian who literally interpreted his six creative days, or whether with the Christian child we reverently say, "In the beginning God created the heaven and the earth." With the "meaning of the world," as philosophers put it, science has nothing what- ever to do; she would simply teach man such use of the world as is conducive to his own safety and well-being, such a way of looking at the world as will deliver him from fear. Surely to the "meaning of the world" to "theories of nature" the race has given sufficient attention; is it not high time we should strive to comprehend that part of the world which most directly concerns us, and which has all the while lain unnoted within our reach? But even here Mr. Balfour would discredit science. Basing an argument on what he terms "mental physiology" he impugns the evidence of the senses; he declares that science has no evidence of the existence of the world of which it tells, is based upon an illusion, exists because of an erroneous view of the natural world. The plain, every-day man of science can for once scarcely trust his eyes as he reads such pages. Now, to any one with sufficient mental equipoise to abide by the earth, to stick to that which the whole experience of ani- mate creation in all past ages has proven true, to any one who abides the common appreciation of fact, such a book, as far as the methods of science is concerned, appears simply as a jeu d' esprit, a bit of dialectic humor; but to multitudes of people who will not do this thing, who, on account of innate prejudice, 24 IOWA ACADEMY OF SCIENCES. or what not, are not especially friendly to the scientific move- ment, such an argument will appear conclusive, demolishing in a sentence all that fifty years of science has built up. Whether such argument takes with it electric lights and cars, bacteriology, modern surgery and photography, is not so clear. But perhaps the most curious index of the present ebb is scientific interest and enthusiasm comes from a quarter where we should least expect it, from philanthropy or altruism, as in these days we are taught to say. The eccentric Russian lioble- man, Tolstoi, regarded in many quarters as the modern oracle of all efforts for social amelioration, he, too, has a griev- ance against science. His is the most marvellous complaint of all. I quote from the Popular Science Monthly, July, 1898: "The strong, sensible laborer supposes that men who study and are supported by his labor, shall be able to tell him where to find happiness. Science should teach him how to live, how to act towards friends and relatives, and how to control instincts and desires that arise within him, how and what to believe. Instead of telling him these things, science talks about distances in the heavens, microbes, vibrations of ether and X-rays. The laborer is dissatisfied. He insists on know- ing how to live. The essential thing is the total view of life, its meanings and aims. Science cannot rise to that view, reli- gion alone can do so. " I consider this a most remarkable utterance, but it simply shows how very far off an intelligent man may be in this year 1898 from a true appreciation of the method, the work and the mission of natural science. To declare that science has not been a blessing to earth's toiling millions can be possible only to a man who chooses to hide himself amid the serfs of benighted Russia, where aristocracy of church and state still holds millions in the superstitious degradation of medieval ages. Surely everywhere west of Russia, there is not a work- ingman wlio does not by virtue of the progress of science find himself to-day better housed, better warmed, better fed, better taught in health and better nursed in sickness than ever before in the whole history of the race. The light of science converts night into day before his footsteps; for a mere pittance, a small fraction of his daily wage, he journeys to and from his work in style befitting a prince; if he be sober, his home is the abode of comfort, the best knowledge of the world is spread before his children, gifted men taught in the ways of science IOWA ACADEMY OF SCIENCES. 25 are instantly at his summons everywhere to save him and his from suffering and disease. Nay, the very fact of the matter is that science made possible the continued existence of Mr. Tolstoi and his serfs, when a few years since but for science- invented steamships and telegraphs all the people of southern Russia would have perished by starvation together. Mr. Tolstoi probably appreciates this, but he fancies that the world suffers more from selfishness and tyranny than from ignorance of nature and her laws, which may be true; but the antidote for tyranny is intelligence, for selfishness wisdom, and in the winning of such virtues science is certainly a contributor not to be despised. The most democratic statesmen in Europe to-day are not the men of religion, the clericals, but the men of science. It is one function of this Academy, at least, to keep the people of Iowa from lapsing in their allegiance to what may well be called, as it seems to me, the noblest and most beneficent intellectual movement of modern times. It would seem gratuitous thus to enter upon a defense of science or the scientific methods; they really need no defense; but after all, it is w^ell sometimes to declare the truth. In fact science, as such, has never been popular. As usual, results only are popular. The toilsome, laborious researches recounted in the tomes of all the academies of earth are not attractive, not popular. They mean long days and nights of weary labor. Faraday and the electricians before him dis- covered and knew nearly all that we know to-day concerning induction and alternating currents, but Faraday never heard through a telephone the voice of his friend, nor walked in the blaze of an electric light. That came later. It is easy for men to sit by an incandescent lamp and write criticisms of the scientific method, but such men ought at least be honest enough to acknowledge their indebtedness, to own that it pays to have scientific work done, however unsatisfactory the method of the scientist may seem to them to bo. How many men there are ready to ridicule meteorology, the latest effort in the field of scientific research, and yet every year, even with our present imperfect methods and knowledge, the saving to humanity by our weather service in property, health and even life itself is of moment incalculable. Besides, who shall doubt that the day is coming when the currents of the upper air may be mapped and known as exactly, perhaps, as those of the 26 IOWA ACADEMY OF SCIENCES. more solid ocean, and although we may never be able to con- trol one or the other, we may better and better adapt ourselves to their vagaries as time goes by. In view, then, of the present need of our own people, and in view of the present status of the world of thought, it does seem to me that the necessity of our organization takes on new importance. We should, as never before, encourage each other to good work, in every way strive to foster the spread of science and its methods among the people of this good state. We are as the scientiiic public servants at Washington, a "university unorganized,'' and while we may guard as zeal- ously as may be needed our fellowship, the council of the Academy, let us yet welcome to membership everybody in this whole state who has within him the impulse of a scientiiic spirit. This fair city of Des Moines surely numbers in its population scores of men in all walks of life who have our work at heart and who, if organized, might second, as nothing else could do, the efforts of this academy. It is one of the beauties of scientific investigation that the problems of science are about us everywhere. Those about the city of Des Moines are quite as interesting, fascinating, no doubt, as any others within an equal area on the face of the earth. It remains only that men open their eyes and see. A local academy of science in this, the capital city, if I may be permitted to suggest, would be a wonderful adjunct to this association and stimulate in a peculiar way an interest in science everywhere. Daven- port has for many years maintained such an institution, famous throughout the world. The geologists of Iowa cannot alone maintain our w^ork, nor can the botanists, nor the chemists, the mathematicians or astronomers, but if all unite, we can develop programs of universal interest, and thus more surely attain that prestige as an institution which would seem to be in keep- ing with the reputation of our state. And let us not for a moment fear that our labor is in vain. The future of Iowa is hardly dreamed to-day by the most enthusiastic of its optimistic citizens. I look forward to the time, and that in no distant future, when the center of wealth and power in this great republic shall be within 150 miles of where we are this evening gathered. It is coming sure as the swift revolving years. The Mississippi valley is certain to be the empire of the world. When that day comes the faithful effort of this Academy will find its own reward. It will then IOWA ACADEMY OF SCIENCES. 27 be seen that we, too, were foundation builders, that upon our work has risen a temple of science commensurate in useful- ness, beneficence and inspiration, with the imperial destiny of oui; river-bordered state. THE COLOR OF DEEP-SEA ANIMALS. BY C. C. NUTTING. The purpose of this paper is to explain the phenomena of bright colors among marine animals living ia the sea beyond the depths to which sunlight can be supposed to penetrate to such an extent as to render bright colors visible. Although there are doubtless actinic eifects of sunlight at considerable depths, we are safe, I think, in saying that colors cannot be clearly distinguished at a depth greater than 100 fathoms. Photographic experiments show that the "extreme limit of effect of the sun's rays on sensitive plates is at a depth of 250 metres," or less than 125 fathoms. As to the facts con- cerning coloration of deep-sea animals — and the deep sea may be considered from our standpoint as any depth below 100 fathoms — all our information leads to the conclusion that the phenomena of bright colors are present in all groups. The main sources from which I have drawn this conclusion are the " Challenger ' " Reports and Narrative, "The Three Cruises of the Blake, " ' by Alexander Agassiz, and my own observations, most of whicli are recorded in my narrative of the ' ' Bahama Expedition'' sent out by the State University of Iowa. Pro- fessor Mosely, of the Challenger staff, says:* "Peculiar coloring matters giving absorption spectra have now been found to exist in all the seven groups of the animal kingdom. The echinodermata and ccelenterata appear to be the groups which are most prolific in such coloring matter. Pentocrinin and antedonin seem to be widely difl'used in immense quantities through the tissues of the crinoids in which they occur; and the echinoderms generally seem to be charac- terized by the presence of evenly diifused, abundant and 'Quarterly Journal of Microscopical Science, xvil, p. 1. 28 IOWA ACADEMY OF SCIENCES. readily soluble pigments. " Again he says "the same coloring matters exist in deep-sea animals which are found in shallow water forms. " Alexander Agassiz says that there are many ' ' vividly colored bathyssal animals belonging to all the classes of the animal kingdom and possessing nearly all the hues found in types living in littoral waters."* He notices the scarcity of blue color, however, having found it only in an encrusting sponge and blue crustacean eggs. The following statements are important: "There is apparently in the abysses of the sea the same adaptation to the surroundings as upon the lit- toral zone. We meet with highly colored ophiurians within masses of sponges themselves brilliantly colored at a depth of more than 150 fathoms." " While we recognize the predomi- nance of tints of white, pink, red, scarlet, orange, violet, purple, green, yellow and allied colors in deep-water types, the variety of coloring among them is quite as striking as that of better known marine animals. " "There is as great a diver- sity in color in the reds, oranges, greens, yellows and scarlets of the deep-water starfishes and ophiurians as there is in those of our rocky or sandy shores. " Among the abyssal invertebrates living in commensalism the adaptations to surroundings is fully as marked as in shallow water. I may mention especially the many species of ophiurians attached to variously colored gorgonians, branch- ing corals and stems of Fentacrinirn scarcely to be distinguished from the part to which they cling, so completely has their pat- tern of coloration become identified with it. There is a similar agreement in coloration in annelids when commensal upon starfishes, mollusca, actiniae or sponges, and with Crustacea and actinias parasitic upon corals, gorgoniansor mollusks. The number of species of crustaceans * * * colored a brilliant scarlet is quite large." "Large masses of brilliant orange- yellow or brownish-pink sponges are constantly dredged.'" The results of my own observations fully confirm the above statements of Agassiz. Ainong the Crustacea we found that a bright scarlet was very common, while the remaining species were generally either green or pale colored. One remarkable exception was a bright blue Solenokunbrus. The echinoderms were particularly striking in their colors. Yellow and purple comatulidic • Three Cruises of the Blake." Vol. 1, pp. BIO and 811. IOWA ACADEMY OF SCIENCES 29 abounded in deep water near Havana. One ophiurian was brown, conspicuously marked with white, others were marked with purple and deep violet. The simple-armed basketfish were bright yellow, or bright yellow barred with brown, or deep orange and rich chocolate. A Luidia was a rich chocolate with conspicuous white spines. Among the sea urchins may be noted a Coefoj)Ieun. collinus, D. inimicus/Lonatura catalina,^'L. megalopai- Driotura robusta,KD. gammaroidea,-''Thamnotettix SQiithi,^T. ciliata,^ Chlorotettix spatulatai?C. unicolor, Phlepsius lobatus, Athysanus striatulu,s,-lA.. magnus, '^A. comma,^A. colon,-'A. punctatus?Cicgidula 6-notataV-Parabolocratis viridis, ^Idiocerus duzei, ^lacropsis apicalisfPediopsis viridiSjKAgallia sanguino- lenta,<. DD. Juga contiguous cephalad of tylus; head nearly as broad in front as between eyes, but little shorter than pronotum. Oncozygia. 42 IOWA ACADEMY OF SCIENCES CC. Scutellum rarely extending farther caudad than corium, in that case sides of pronotum always entire near lateral angle. I). Jugum with a prominent lateral tooth near apex, or with apex pointed and projecting far ceph- alad of tylus; sides of head not distinctly sinuate just cephalad of eyes, antennal tubercles visible from above, and eyes placed close to cephalic angles of pronotum. (Tribe Halyaria.) E. Jugum with lateral tooth near apex; antennal segment 2 cylindrical, shorter than segment 3; . venter with shallow mesal sulcus; body rather broad. Brochynieiia. EE Jugum without lateral tooth, somewhat pointed at apex, projecting far cephalad of tylus; antennal segment 2 triangular, longer than segment 8; venter without sulcus; body elon- gate. Mecidea. DD. Jugum without lateral tooth; apex usually rounded, rarely pointed, in that case not projecting cephalad of tylus; sides of head usually distinctly sinuate near eyes, sometimes almost straight, in that case either antennal tubercles not at all visible from above or the eyes quite distant from cephalic angles of pro- notum. E. Head triangular, very convex on dorsal sur- face, not less than seven-eighths as broad as scutellum; juga distinctly longer than tylus; apex of corium broadly rounded. (Tribe Aellaria.) F. Pronotum with three longitudinal low ridges; cephalic angles of pronotum pro- jecting conspicuously cephalad. Aelia. FF. Pronotum with a single (mesal) longitud- inal ridge; cephalic angles of pronotum not projecting cephalad. Neottig/ossa. EE. Head of various forms, usually only slightly convex on dorsal surface, less than seven- eighths as broad as scutellum; juga usually no longer than tylus, and apex of corium with a distinct though usually somewhat IOWA ACADEMY OF SCIENCES. 43 rounded lateral angle; rarely juga longer than tylus or apex of corium broadly rounded, in either case the head only about two-thirds as wide as scutellum. (Tribe Pentatomaria.) F. Segment 2 of venter unarmed, neither spinous nor tuberculate on meson. G. Odoriferous orifices either far laterad of coxse or distinctly elevated or con- tinued in a sulcus; head more com- monly not strongly bent ventrad, lateral margins of juga sometimes narrowly refiexed, reflexed portion never greatly swollen. H. Scutellum with apex broad and rounded, lateral margin scarcely con- cave at any point; head bent strongly ventrad. Cosmopepla. HE. Scutellum usually with apex dis- tinctly narrowed and lateral margin concave toward apex; otherwise the head little or only moderately bent ventrad. /. Odoriferous orifices either without a sulcus, or with a sulcus ending suddenly, not continuing into a gradually disappearing wrinkle. J. Veins of membrane irregularly anastomosing or irregularly furcate or ramose. K. Lateral margin of prono- tum entire, unarmed; lateral angle rounded, not at all produced. L. Scutellum broadly rounded at apex, as long or nearly as long as cor- ium; apical margin of corium rounded, apical angle obtuse. Coenus. LL. Scutellum narrowed at apex, not extending so far caudad as corium; 44 IOWA ACADEMY OF SCIENCES. apical margin of corium nearly straight; apical angle acute. 31. Bucculas increasing in height caudad, end- ing abruptly; lateral margin of pronotum not explanate; frena reaching just to mid die of scutellum; ros- trum extending a little caudad of medi- coxse. Byiiwiiarcys. MIL Bucculse elevated in- to an angle at cepha- lic end, less elevated caudad; lateral mar- gin of pronotum ex- planate cephalad; frena reaching be- yond middle of scu- tellum; rostrum ex- tending caudad of post-cox83. Menedei^. KK. Lateral angles of pronotum produced into a conspicuous spine. Proxi/s JJ. Veins of membrane simple or slightly furcate. K Frena extending beyond middle of scutellum. L. Tibiae all terete, with- out sulcus, if. Joint 1 of rostrum extending a little beyond bucculse. Mormidea. MM. Joint 1 of rostrum shorter than buccu- lse. Oebalus. LL. Tibiae sulcate above. IOWA ACADEMY OF SCIENCES. 45 M. Cephalic j^art of lat- eral margins of pro- notum crenulate, lat- eral angles promi- nent, either rounded or pointed; head, in- cluding eyes, not dis- tinctly wider than long. EuscMstus. MM. Lateral margins of pronotum entire, lat- eral angles rounded, not prominent; head, including eyes, dis- tinctly wider than long. Cklorochroa. KK. Frena not extending beyond middle of scutellum. L. Lateral margins of pro- notum with a prominent process slightly bent caudad at lateral angles. Prionosoma. LL. Lateral margins of pro- notum entire, lateral angles rounded. M. Dorsal surface with coarse, black punc- tures, irregularly ar- ranged especially on the pronotum. Trichoj)epla. MM. Dorsal surface with finer regularly ar- ranged punctures. Carpocoris. II. Sulcus from odoriferous orifices continued laterad in a gradually disappearing wrinkle. J. Juga not longer than tylus. Thyanta. 46 IOWA ACADEMY OF SCIENCES. JJ. Jug-a longer than tylus, contig- uous at their cephalic ends. K. Apical margin of corium uniformly convex; lateral margin of head very slight- ly sinuate cephalad of eyes. Peribalidi. KK. Apical margin of corium very slightly sinuate near lateral end; lateral margin of head distinctly sinuate cephalad of eyes. HoJcostethus. GG. Odoriferous orifices situate just cepha- lad of lateral border of post-coxae, with- out sulcus, scarcely elevated; head strongly bent ventrad, front almost ver- tical; reflexed lateral margins of j ga much swollen. Murgantia. FF. Segment 2 of venter with a mesal spine or tubercle pointed cephalad. G. Metasternum little elevated, never with a bi-lobed process extending cephalad of medi-cox9e. 77. Segment 5 of antennae less than twice as long as segment 2; scutel- lum and pronotum nearly or quite concolorous. Nezara. HH. Segment 5 of antennae more than twice as long as segment 2; apex of scutellum and cephalic half of pro- notum much lighter in color than remaining portions. Banasa. GG. Metasternum strongly elevated, pro- duced far cephalad between the medi- coxse into a bi-lobed process. Eclessa. A A. Tarsi 2 jointed (sub-family Acanthosomime). Acanthosoma. IOWA ACADEMY OF SCIENCES. PRELIMINARY REPORT ON THE DIATOMS OF IO^A^A. BY P. C. MYERS. Within the last two years the author has often had occasion to congratulate himself for having acted on a suggestion from Prof. B. Shimek, of the State University of Iowa, to take up the study of a group of organisms which hitherto had, from the botanists of this state, received but scant attention. The diatomacesB constitute a group of microscopic organ- isms hovering near the place of meeting, if such there be, of plants and animals. Their closest affinities, however, seem to be with the plants. Unicellular though they be, they make for themselves a glassy covering, whose two parts fit together as the top and bottom of a pill box. Chlorophyl is present, which, however, is masked by a brown coloring material called diatomin. Nearly all these little organisms have the power of movement; a graceful, gliding motion that reminds one of little steamboats. Their study is connected with considerable difficulty, which probably accounts for their being neglected. First. — They must be collected, a not o'er easy task. Second. — They must be cleaned, in which not less than seven separate and distinct operations are necessary; some of these are boiling in nitric acid, immersion in potassium permanganate for three or four days, boiling in hydrochloric acid and a deal of washing. Third. — They must be mounted, one at a time, on separate slides. As these little objects range in size from one-fiftieth of an inch, in the largest, to one-two-thousand-five hundred-for- tieth part of an inch in the smallest, it cannot be said to be heavy work, but it requires considerable concentration of the attention. Fourth.— Thej must be identified. As the literature is badly scattered, one cannot hope to do much without several expen- sive sets of books and pamphlets. Even then there is a little 48 IOWA ACADEMY OF SCIENCES. truth in the remark made by another botanist, with a sniff, that you might as well try to classify wall paper. The diffi- culty, however, is not greater than in other orders of equal size. At first it might appear that the state of Iowa, with its monotonous rolling prairies would offer little diversity of aquatic plant life, but this has not proved to be the case. For present purposes the various localities where diatoms are found may be grouped in four divisions. First. — Creeks and rivers, with the bogs and old river chan- nels connected with them. Second. — Springs, with the bogs and ditches watered by them. Third. — The lakes found in that portion of the state covered by the Wisconsin drift. Fourth. — Fossil deposits. The first localities named, the creeks and rivers, were the first from which material was collected. Here abound the smaller naviculse, synedree, melosirse, and most abundant of them all, the gomphonemsD, which may be seen as long, gela- tinous streamers of a rich brown color, in moving water, or as a covering on the stones in rapids and cataracts. In the brooks and ditches the more fragile forms of nitzschia and synedra are found. Under favorable conditions these little organisms cover the bottom of the brooks and ditches to a depth sufficient to color everything a rich brown. When the sun shines on them the oxygen liberated raises them to the surface of the water and they are carried along until they strike a twig or board or other obstacle, where they may be seen at times an inch in depth and several square feet in extent. East of Iowa City, about two and one- half miles, there is a prairie slough, having in it at one point a broad and shallow basin, where the water stands a greater portion of the year. In the month of June this presents to the diatomist at least, a most remarkable appearance. In this basin, covering an extent of about an acre, and to the depth of eight or twelve inches, is a fiocculent seal brown mass of living diatoms. Here Fragillaria virescens stretches its tiny ribbons, and Meridion intermedium spreads its miniature fans in numbers innumerable. In the northern portion of the state, where the rivers are but little more than motionless lagoons, the amount of aquatic material is indeed prodigious. In such quantities do algse, IOWA ACADEMY OF SCIENCES. 49 lemnas, potomagetons, wolfia and diatoms grow, that the river is literally choked from bank to bank. In the northeast corner of the state, however, the conditions are altogether different. The drainage system there is any- thing but poorly developed, it being a part of the state not known to have been glaciated. Many forms of diatoms are found here, not common to other localities in the state. The Missouri river and its immediate tributaries offer but little that is interesting to the diatomist. But few species are found here, as the rapid currents and ever changing banks and beds of mud do not permit of their gaining a lodgment. The second group of localities, the springs and bogs, offer us a flora at once more varied and robust. Here are found the larger naviculse, with Suriraya splendkla, CainpulocUscus spiralis, Stauroneis phoenecenteron and a host of others, all with frustules strongly silicified. In a little bog, fed by a spring, some four miles from Iowa City, in a place but six feet square, the spe- cies ('coiipylodiscus spiralis, a very large and pretty diatom, occurs in large numbers, its only known locality in the state, except, perhaps, one on the Des Moines river near High Bridge. The third group of localities, the lakes in that portion of the state covered by Wisconsin drift, presents features of more than usual interest. Clear Lake, located in Cerro Gordo county, is about six miles long by three wide. It belongs to the class of "kettle holes, ' ' and lies on the eastern edge of the Wisconsin drift, occupying the highest ground in that region. The town of Clear Lake has an altitude above sea level of 1,238 feet, while at Mason City, nine miles east of there, the altitude is only 1,128 feet, or 110 feet lower. On the north, west, and south much the same conditions prevail. This falling away in all directions brings about the follow- ing results : First.— Very little surface drainage; the slope toward the lake being, in some places, only a few feet, while on the west it reaches its greatest length of about one mile. Second. — There is no overflow, a state of equilibrium existing between rainfall and evaporation. Here, then, are the con- ditions necessary for the deposition of a bed of organic mate- rial. On examination the lake showed the following conditions : The entire bottom, except a narrow strip along the shore 4 50 IOWA ACADEMY OF SCIENCES. where the undertow keeps it clean, is covered with a bluish- black material, light of weight and very soft and yielding, com- monly called mud. This is everywhere underlain by a heavy, tenacious, gravelly, blue clay. In the west end of the lake, at what is called the rice beds, where the water is only about two feet deep, the aforesaid mud reaches a depth of eighteen feet. Near the center of the lake are the "moss beds," with the water three feet deep and a deposit of twenty-one feet. About midway between the "moss beds" and the eastern shore the water reaches its maximum depth of fifteen feet, with the depth of the deposit undetermined. On examination this deposited material proves to be 75 per cent organic matter, 12^ per cent fine sand and 12^ per cent diatom frustules. On an average this would give us a bed of diatoms two and one-half feet thick over an area of eight or ten square miles. The number of species found in this material will number sixty, among them some of the largest and most beautiful fresh water forms known, such as Suriraya robusta and biseriata, Navicnla nobilis and peregrina, Cymafojjleura solea and eJUptica. Here, too, are found JSltzschia siginoklea, 400 to 500 micra long, with its 66,000 strise to the inch, and Nitzschia palea with 91,440 strise to the inch. The species and individuals both decrease in numbers as one passes downward, /. e., there are more diatoms growing there now than at any previous time. The increase in species has most likely been accomplished by waterfowl carrying hither bits of mud from other lakes. One feature of the Clear Lake diatoms was very puzzling. What appeared to be Pleuromgiua attenKatuin, which usually has a length of 190 to 250 micra, was habitually 250 to 300 micra long. Vyinbella ehrenbergii presented the same variation, as did likewise half a dozen other species. This variation toward larger forms came, finally, to be so common an occurrence that it was concluded that it perhaps was due to an extraor- dinary amount of silica in solution, and other very favorable conditions. Spirit Lake is located in Dickinson county, Iowa, on the western part of the Wisconsin drift. It resembles Clear Lake in most essential points. The sand beach, however, is wider, and it is not so rich in microscopic forms. The deposit is not so great, but the water somewhat deeper. IOWA ACADEMY OF SCIENCES. 51 East Okoboji Lake is composed of three small lakes in a chain, the water varying from three feet in the upper one to eighteen or twenty feet in the lower one. The deposit varies also from eight feet in the upper to a much greater depth in the lower. Here there is a much greater percentage of sand than in Clear Lake, due to more extended surface drainage and steeper hills. The channel, however, which connects East Okiboji and West Okiboji Lakes, is the most remarkable place of all. Remarkable, not only for the number of diatoms, but for a host of other aquatic forms growing in the most lavish pro- fusion. The conditions here are certainly very favorable for plant growth. High hills, covered with trees, protect the channel from the winds, and its form precludes the possibility of large waves. Then, too, a gentle current sets from one lake to the other, keeping the water in fine condition. In the fall, after the larger plants have passed their perfection and have begun to die, the diatoms overrun them all and, indeed, every other thing below the surface of the water. The com- mon bladderwort becomes the home of vast colonies of the stalked forms, as cocconema, gonphonema, bands of fragil- laria, with long, acicular synedra intermingled. Acres are thus covered, where there are no large waves and the water is not too deep. In those parts of the lake where rushes grow, each one is covered below the water line with a layer a half an inch or more in thickness. Across this channel a railroad was built, and in so doing a diatomaceous deposit was found fifty-two feet deep In West Okiboji Lake water was found 125 feet deep, the deposit being of unknown depth. So soft and yielding is this material that a dredge, weighing only two or three pounds, when dragged along the bottom sinks into it to a depth of ten or twelve feet. In comparing the species found here with those found in Clear Lake, both lying in the same geological formation and no great distance apart, it is seen at a glance that they are utterly different. In Clear Lake such genera as suriraya, navicula, cymbella, eunotia pleurosigma and cymatopleura are found, as compared with cocconema, odontidium, stictodis- cus and synedra in Okoboji Lake. Silver Lake also adds a small quota, but has not been care- fully examined. 52 IOWA ACADEMY OF SCIENCES. The fourth division, that of fossil diatoms in Iowa, is reserved for another paper. The number of counties in the state which have been visited by the author, and those from which material has been received, number twenty-nine.* At some future time we expect to present to the people of Iowa who are interested in this work, a descriptive list of all the species of diatoms found, with a photograph of each. REPORT ON A FOSSIL DIATOMACEOUS DEPOSIT IN MUSCATINE COUNTY, IOWA BY P. C. MYERS. Previous to the present year no fossil diatoms had been found in Iowa. On October 20, 1898, Prof. J. A. Udden, of Rock Island, 111., w^hile engaged in work for the Iowa Geologi- cal survey, found and sent to Prof. S. Calvin, of the State Uni- versity, some diatomaceous earth. This material was taken from below the loess in Muscatine county, Iowa, and was turned over to the author for examination. It was of a dull, yellow color, composed of sand and decayed vegetable matter and a few diatoms. The species, with their general distribution and habitat, are as follows: Navicula abaujenssis Pant. Fresh water fossil in Hungary. Navicula borealis (Ehr.) Kuetz. In fresh water, cataracts, rivers and wet moss, all over Europe and America. Navicula fjibba (Ehr.) Kuetz. Everywhere in fresh water. Navicula major Kuetz. A cosmopolitan species in fresh water. Nivicula nobilis (Ehr.) Kuetz., var. dacti/Ius (Ehr.) V. H. In bogs and fossil. Navicula rupestris (Pinn.) Hantz. On wet rocks. Navicula placentula (Ehr.) Kuetz. In rivers in Europe and America; also fossil and marine. * As there are many places in the state stiU unexplored, I desire at this time to say to the members of the Academy that I should be g-lad of their co-operation in this matter. IOWA ACADEMY OF SCIENCES. 53 Eunotia dloclon (Ehr.). Rivers, springs, rapids, on wet rocks and fossil. Eunotia gracilis (Ehr.) Rabeuli. In boggy, swampy places. Eunotia major (Win. Sm.) Rabeuh. In fresh water every- where. Stauroiiers phoeneceinteron (Nitz.) Ehr. Cosmopolitan. Cystopleura gibba (Ehr.) Kimze. Common in fresh water; also fossil and marine. Ct/nibeJla ei/nibiforinis (Kiietz.) Breb., var. parva (Win. Sin.) V. H. Common everywhere in fresh water. Hantzschia. ainjjhyoxis (Ehr.) Grun. Common everywhere in fresh water. Judging from the above and from evidence which does not appear here, /. e., the comparative number of individuals in each species, the condition was probably that of a shallow bog, subject to gentle overflows from some creek or river. DIATOMACEOUS EARTH IN MUSCATINE COUNTY. BY J. A. UDDEN. While at work on the geology of Muscatine county last sum- mer, the writer found some diatomaceous earth in tne south bank of the creek which runs west near the south line of sec- tion fourteen, in Cedar township. It is associated with a peaty layer, which overlies it, and which appears somewhat dis- turbed. This peat is overlain by tine laminated sand and silt, which here forms the base of the loess. Below the peat bed and the diatomaceous layer there is a white sand without a trace of ferruginous stains. Boggy conditions are indicated, or perhaps the conditions of a lake or pond. The diatomace- ous earth itself does not lie in a continuous layer, but in a broken layer, or in small pockets, which are scattered. It has a peculiar dull, pink color, and this has lately enabled the writer to find small lumps of it in the peaty soil under the loess in Scott county, near Davenport. It was from this loess that the remains of a mastodon have been reported by Mr. Pratt. 54 IOWA ACADEMY OF SCIENCES. THE PINE CREEK CONGLOMERATE BY J. A. UDDEN. In the right bank of the west branch of Pine creek, a short distance north from where it leaves section thirty-four in range one west, township seventy-seven north, there is a pebbly sandstone, unlike the coal measure conglomerate in the sur- rounding country. This sandstone is mostly brown in color, changing to yellow. It has a rather coarse texture, compared with the coal measure rocks, and is somewhat more variable in this respect. The best exposure appears in a small gully, which comes down the hill from the west, some twenty rods north of the south line of the section. In all a thickness of about sixteen feet is seen. Springs issue from the base of this rock, along the slope to the creek, indicating finer impervious underlying beds. The lower part of the section has one ledge which is two feet in thickness. But the bedding is irregular and the layers vary much in thickness in short distances. Some of the ledges are strong enough to be used for building stone, while one or two are loose sand. Even the hardest lay- ers break easily under the hammer. In these the sand and gravel is cemented by a black matrix of peroxide of iron. The uppermost ledges are somewhat finer than the lower. Two sets of quite regular joints here cut the rock. One set bears west of north and the other north of east. Along these joints the ferruginous material is most profusely deposited. Some of the ledges are cut up into rhomboidal blocks about a foot in length and from eight to ten inches in width. These have a shining black hard crust, half an inch or more in thickness, which on some of the blocks has separated from the lighter and softer rock within, forming thin, straight and smooth plates. Above this brown sandstone there is a yellow loose sand containing small boulders of greenstone and granite. On top of this sand there is boulder clay and loess. Small expos- ures of the conglomerate occur for a distance of a quarter of a mile along the west side of the creek to the south of this place. IOWA ACADEMY OF SCIENCES. 55 The degree of induration, the pronounced jointing, and the general ancient aspect of this conglomerate render it rea- sonably certain that it is not a part of the drift which overl es it. But it has pebbles of Archsean rock, and one of these was nearly six inches in diameter. None of them were observed to be scored, though quite a number were examined. The aver- age size of the pebbles is from one-fourth to two inches in diameter. On the other hand, it is not believed that it can belong to the coal measures. Some of the pebbles appear to be pieces of coal measure concretions and lumps of coal meas- ure clay, and the aggregation of rocks represented in the pebbles is unlike anything observed in the coal measure con- glomerate. For comparison, a collection of fifty pebbles was made, representing the average sizes. The proportion of specimens of dilferent rocks in this lot was as follows: Yellow chert 32 per cent Greenstone 26 " Granite {mostly red) 10 " White quartz (some of a faint, pink color) 8 " Fragments of coal measure rock 4 " Light red orthoclase 2 " Black felsite 2 " Porous Niagara chert 2 " Chalcedony 2 " Orthoclase-biotite rock 2 " The only conclusion which can at present be drawn, as to the age of this conglomerate, is that it is post- Carboniferous and preglacial. Dr. Calvin, who has seen it recently, pro- nounces it identical in nature to the Rockville conglomerate described by McGee. It also somewhat resembles the Cretaceous conglomerate found in Guthrie county by Mr. Bain. Possibly it may be an outlier of the Lafayette formation, observed far- ther, south by McGee and by Salisbury. In the south bluff of West Hill in Muscatine, just east of Broadway street, there lies on top of the coal measures and under the drift a small remnant of a conglomerate somewhat resembling that above described. It is seen for a distance of only three or four rods and its greatest thickness is three feet. It is plainly unconformable with the beds below. The base is a very pebbly sand, held in a dark ferruginous matrix, which, in some places, does not wholly fill the interstices between the pebbles. The upper surface is a brown ferruginous, moder- ately fine sandstone of about the same hardness and aspect as 56 IOWA ACADEMY OF SCIENCES. the middle ledges in the Pine creek conglomerate. It is seen to contain three rounded boulders from eight inches to one foot in diameter. One of these consists of gneiss, one of mica schist and one of quartzite. In a collection of 100 pebbles from this ledge, different rocks were represented by the number of pebbles indicated in the following list: Greenstone 26 per cent White quartz 26 " " Yellow chert 18 '' " Granite (mostly red) 7 " " Light red orthoclase 5 " " Coal measure rock 4 " " Black felsite 3 " " Quartz-biotite schist 3 " " Faintly pinkish white quartz 2 " " Quartz speckled with jasper 2 " " Red quartzite 1 " " Hornblende rock 1 " " Milky quartz 1 " " Gneiss 1 " " The author is inclined to the opinion that this conglomerate in Muscatine and that exposed on Pine creek are both outliers of the same formation, but he has no suggestion to offer as to what age they really belong farther than as above stated. FOREST TREES OF ADAIR COUNTY, IOWA. BY JAMES E. GOW. In order to understand the forestry conditions of Adair county, a short description of the lay of the land and the nature of the soil is first necessary. The county lies along the crest of the " grand divide," between the Mississippi and the Missouri, so that a line drawn along the crest of the ridge traverses it diagonally from northwest to southeast. The land is undulating enough to secure an easy natural drainage, but not so undulating as to be difficult of cultivation, except in a few isolated localities. The soil is a rich, black loam, varying in thickness from a few inches to ten or fifteen feet and under- lain by a stiff, yellow clay. Here and there, the larger streams may be found flowing over beds of limestone, but as a rule IOWA ACADEMY OF SCIENCES. 57 they flow either through the black surface soil or the yellow clay below it. Of these streams, North river and Middle river enter the Des Moines, while Grand river and the Nodaway flow into the Missouri. Although commonly ca'led rivers, none of them attain to sufficient size, in Adair county, to deserve the name, but all become streams of considerable size before losing their identity in the Missouri or the Des Moines. The rivers along whose course is found the heaviest timber are Middle river and the west branch of the Middle Nodaway, and it is on these streams that the greatest variety of species have been found and most of the observations have been made The prairie in Adair county is practically bare. The only trees or bushes ever found upon it in any abundance are the hazel and bur oak, and these have been largely grubbed out and destroyed. The wild plum, wild cherry and American crab, may occasionally be found on the high prairie, but they very seldom, if ever, occur there unless protected by other low timber, and as the bur oak and hazel are destroyed, they van- ish also. So it is along the streams that the student of forestry must seek his information. Even a cursory examination of these streams is sufficient to show that, with few exceptions, the southern or western bank is steep and rough, while the northern or eastern bank is smooth and rises with a gentle slope. Along most of the course of Middle river, through the county, the southwestern bank consists of steep clay bluffs, densely wooded and rising abruptly from the water, while the northeastern bank slopes up very gradually from the water— making a wide, level valley or bottom, which is usually either destitute of trees, or less heavily wooded than are the bluffs of the opposite bank. The same condition may be noticed quite generally with regard to the smaller streams. In driving along the road it is noticeable that the steepest hills face the north or east, and the gentler inclines the south or west. The reason for this must be that the erosion has been greater on the north than on the south bank, owing to the fact that the former receives the full rays of the spring sun, while the southern bluff lies in shadow most of the day. This, of course, would cause the snow and ice upon the northern slope to melt very quickly, making con- siderable erosion, while upon the southern bank it would melt much more slowly and hence cause much less erosion. Where the course of a stream is southward it is the left bank which 58 IOWA ACADEMY OF SCIENCES. shows the greater signs of erosion, because it is exposed to the burning rays of the afternoon sun, while the right bank is in shadow during the hottest part of the day. The effect of this process upon the distribution of timber is evident. The steep bluif-land upon the southern or western bank of a stream is usually heavily wooded, while the flat "bottom" upon the northern or eastern side is often \rery sparsely covered with trees and sometimes quite bare. Before the advent of civiliza- tion the southern bluffs often held the moisture of the winter snows and spring rains until after the season of prairie fires, thus giving the trees sprouting upon their surface a chance to grow, and, when the trees had grown large enough, they fur- ther protected themselves from fire, the surrounding grass being killed out. But the northern bank, which had to face the rays of the spring sun, was well dried by the time the grass on the prairie was dry enough to burn, and so the trees growing upon its surface were destroyed. This is the process which must have taken place during many years before the day when the plow of the first white settler cut the soil of western Iowa. Its effects are still noticeable, but not so noticeable as they must have been at an earlier day. To-day, practically all of the trees in Adair county are of second growth. There are left only a few isolated specimens of the so-called first-growth timber. Since the days when the prairie fires ceased, seedlings have taken root in the fertile flats which form the northern and eastern banks of our streams, and have grown into trees of goodly size, and in some places the southern bluffs have been shorn of their trees. Still, in a gen- eral way, the primitive condition is still noticeable; the timber on the southern bluff is usually larger and thicker than that on the northern bottom. It is noticeable, too, on the prairie — wherever enough of the original brush has been left to indicate anything at all. The hazel and bur oak will grow on a south- ern or western slope, but they are not generally found in such a situation. Usually they seek the northeastern side of a hill, and there they flourish luxuriantly. As has been said, there is very little of the first-growth timber remaining in Adair county. The first settlers of the county found along the streams a thick growth of large, well developed trees. Since then almost all of these trees have been removed, until there remains very little timber which was well grown at the time of the first settlement of the county, IOWA ACADEMY OF SCIENCES. 59 forty years ago. In its place has appeared a growth of smaller trees, which were saplings when the older trees were destroyed, or have grown from the seed since that time. Here and there may be seen a relic of the first growth — some giant of the forest who towers high above all the trees about him but, as a rule, the forest of to-day is made up of younger and smaller trees than those which composed the forest of forty years ago. The area, however, of the timber land along the streams remains about what it was at an earlier day. It may possibly be a trifle less, but only a trifle. The second growth covers substantially the same area that was covered by the first growth. The chief denudation of the country has come about, not through the destruction of the larger trees which grow along the rivers, but through the removal of the bur oak, hazel, and other prairie species. Before the settlement of the county — if we may trust the accounts of the earliest settlers — a large part of the prairie was covered with t rush. To-day the greater part of the brush is gone and the land upon which it grew is under cultivation. The absence of the brush from the prairie tends to increase erosion and decrease the conservation of moisture in the soil, but its destruction was inevitable because necessary to the successful carrying on of agriculture; and, as conditions grow harder and the land becomes more densely populated and more closely farmed, the destruction of that which is left will become necessary and inevitable. But as the prairie brush is destroyed greater care than ever should be taken to preserve the large and really valuable timber along the rivers, and to extend its area if possible. The people of Adair county have not carelessly destroyed their forests as have the people of many portions of the country. They have preserved them, but it cannot be said that they have preserved them understandingly. The second growth has come in so thick in many places as to choke itself. Valu- able walnut, ash or hickory trees are often j^revented from making a good growth by the thickets of maple, elm or elder in which they grow, and, too often, when the needs of the farmer force him to cut firewood for himself, he takes all the trees from a certain area, instead of cutting out only those which can best be spared and leaving the remainder. A little popular education on the subject of forestry might remedy these difticulties and teach our farmers to take a greater inter- est in their forests and better care of them. 60 IOWA ACADEMY OF SCIENCES. During the past twenty-five or thirty years the extent of artificial groves in Adair county has grown from nothing at all to many acres. Almost every farm-house now has a yard full of trees and a wind-break to the north, and hedges of maple, willow and osage orange line many of the roads. Unfortu- nately, the best species for the purpose are seldom used in these groves. Instead of planting walnut, ash or white oak, our farmers usually plant the soft maple, on account of its rapid growth, and the result is that no sooner do the trees arrive at a respectable size than the winds play havoc with them. The box elder is much used, more on lawns, however, than in groves, and although rather soft it is a good tree and a very pretty one when properly trimmed. The willow figures occasionally in groves, but more frequently in hedges on low lands, where the maple is also sometimes used. Groves of walnut or of ash are occasionally met with, but are not com- mon. The Cottonwood is used but rarely and the oak never, so far as we know. While these artificial groves are of little value in conserving moisture, preventing erosion and preserv- ing true forest conditions, they are useful in breaking the force of the winter winds, and they exert more or less of a civilizing influence by adding to the beauty of the monotonous prairie landscape and the comfort of life on the farm. In Adair county a few species of trees, which are common elsewhere in Iowa, are conspicuous for their absence. The butternut, sycamore and hard maple are found in Madison county, along the course of the Middle river, but we have been unable to discover that a single specimen has ever been found growing wild on this side of the line. The Missouri hickory grows along the Nodaway, it is said, north of the state line, but does not extend this far north. The pawpaw is found occasionally in southern Iowa, but has not been found in Adair county. The fact of a few birch trees having been observed, some twenty years ago, near the town of Casey, on the north line of the county, led to a search through that locality, but no birches were found and none have been found in any part of the county. Both the butternut and birch are reported as being common along the course of the North Raccoon river in Guthrie county. Following is a list of the species of forest trees found grow- ing in Adair county. The nomenclature of Wood has been fol- lowed throughout: IOWA ACADEMY OF SCIENCES. 61 Ulmus aitwrieana L. White elm. Common on banks of streams and in valleys, sometimes growing a little way up the sides of bluffs and occasionally found on upland. Attains its greatest size on low ground. Well distributed throughout the county. Frequently planted as a shade tree UhiiK.s fiilva L. Red elm. Slippery elm. Found only on low land. Common. A smaller species than the preceding. Ulmus raceiiiosa Thomas. Rock elm. A rare species which we have not found within the county. Has been reported by an early settler, w^ell acquainted with the native timber, as growing in scattered locations along the west branch of the Middle Nodaway. Quercus inacroGarpa Michx. Bur oak. Scrub oak. This species is very common and occurs most frequently on the sides and summits of river bluffs and on the high prairie, where it is a gnarled, stunted, shrubby tree, varying in height from ten to twenty feet. Occasionally, however, it may be found growing in rich river bottoms, where it becomes much straighter, resembling the white oak in its habit of growth and attaining a height of thirty or forty feet. It is the most abundant species of oak and one of the most abundant trees in Adair county. On the prairie it and the hazel appear to be inseparable companions. The bur oak is almost the only tree which safely resisted the prairie fires and grew in abundance on the open prairie, before the advent of civilization. Clumps of it are found scattered over the prairie at intervals — remnants, evidently, of the more abundant growth which once covered the country. Querent rubra L. Red oak. A handsome, straight tree, found in tolerable abundance on the bluffs near the larger streams and occasionally on bottom land or in thickets of bur oak on the high prairie. Qicercus alba Li. White oak. Not uncommon. Found along the larger streams — seldom, if ever, on prairie. Prefers rough, clay bluffs. Quercus cocclnea var. Unctoria Wang. Black oak. Not so abundant as the red oak and occupies the same habitat. Does not attain the size of either of the preceding species. Negundo aceroides Moench. Box elder. This is probably the most common of all the trees native to Adair county. It is found along all the streams w^herever there is any timber at all and is often planted on lawns and in groves on the prairie, where it flourishes. 62 IOWA ACADEMY OF SCIENCES. Acer rnhnnii L. Red maple. Soft maple. Swamp tnaple. Quite common. Grows luxuriantly on the banks of streams and in all low, moist places. Very frequently planted in groves and on lawns, where its soft wood is often broken by high winds which it is unable to resist without the protection of larger timber. ('anja alba N. Shell-bark hickory. Common along the larger streams, where it grows well up on the bluffs, and occasionally in the bottoms. Carya glabra Torr. Pig nut. A somewhat smaller and coarser species than the preceding. Usually found on lower land. The two species are about equally common. Juglans nigra L. Walnut. Common along the larger streams, where it grows luxuriantly and attains a good height. Never seen on the prairie, except when planted there, which is not often the case. The walnut was much more abundant a quarter of a century ago than it is to-day, although it is still a very common tree. Owing to the value of the wood it has probably suffered more at the hands of woodmen than has any other tree found in Adair county. Tilia americana L. Basswood. Linden. Quite common in all river bottoms. Seldom seen elsewhere. Populu.s canadeniiis Desf. Cottonwood. Not rare. May be found in occasional clumps in all low, moist situations. Is occasionally planted in groves or hedges. Celti>i o(ride)if(Ui.s L. Hackberry. Not rare. Found only in timber along the larger streams — always on low land. Is occasionally transplanted and makes a very handsome lawn tree. AemuluH flava Ait. Buckeye. A tolerably common species along Middle river and the Nodaway, but never found on Grand river. GlediUchia tracanthus L. Honey locust. Not common. Is found in scattered groups along both the Nodaway and Middle river. PruiiHH serofhta Ehr. Wild cherry. Tolerably common along the roads and on all waste land. Prunus americana L. American plum. Wild plum. Very common on all low lands. About equally abundant in the larger timber and along the small prairie streams where it and the wild crab are often the only species of trees. Occurs occasionally on the uplands in company with hazel, bur oak and sumac. IOWA ACADEMY OF SCIENCES. 63 Ostrya virginica Willd. Ironwood. Not uncommon along- the Nodaway, and may be found on Middle river, but not abundantly. ('rat(egus coccuiea L. Hawthorn. White thorn. Red haw. Common on low land, usually in larger timber. C. tomenhmi L. Black haw. Not very common. Found in greater abundance on the west than on the east side of the county. Pyrus coronaria L. Crab apple. Very common on all low land, whether open or covered by larger timber. Corruis jKniicifhffa Lt'ller. Dogwood. Common in thickets, both in valleys and on the higher land. Ehiis glabra L. Sumac. Common in thickets along the side and crest of river bluffs and on the high prairie. Pound usually with hazel and bur oak. Sambiictis canadensis L. Elderberry. Common in thickets on all waste, rich land. Prefers the bottoms. Prunvs virginiana L. Chokecherry. Fairly common on all low land. Usually found in hick ts of other timber. Corylus auiericana Walt. Hazel. Very common on all rough, rolling land, especially near the larger streams. Very seldom found on low land. Originally a great part of the prairie was covered with hazel, but most of it has been removed. A good deal yet remains, however, and all along the larger streams it is very abundant. Salix nigra Marshall. Willow. Tolerably common on all low, moist ground. Vitis cestivaUs L. Wild grape. Common in all timber. Lonicera parvijlora Lam. Not common. Found occasionally in heavy thickets. EFFECTS OF A SLEET STORM ON TIMBER. BY JAMES E. GOW. On the nigQt of the 9th and the morning of the 10th of Feb- ruary, 1898, a heavy sleet storm passed over Adair county, Iowa. The storm began not very long after midnight w th a brisk rain which froze as it fell and adhered tenaciously to trees and other objects with which it came in contact. The 64 IOWA ACADEMY OP SCIENCES. wind at the time was slightly west of north and was not blow- ing at all briskly. The day preceding the storm had been unusually warm, for the time of year, with a cloudy sky, a slight breeze from the north and a very humid atmosphere. About 3 o'clock on the morning of the 10th the trees, which had become heavily laden with ice, began to break. Had there been a heavy wind at the time, the damage to the trees would have been immense; as it was, the damage was very great and in the town of Greenfield the people were very generally awakened by the crashing of the breaking trees, which lasted almost continuously from 8 o'clock until daylight. Morning revealed the immense damage which had been done to the shade trees of the town. Most of these are soft maples and had yielded readily to the weight "of ice, so that a large pro- portion of them were damaged and some were quite ruined. Owing to the stillness of the air the ice adhered about equally to all sides of the trees and, on trees of straight growth, the breakage was equal on the different sides. The damage wrought by the storm was most severe on the soft maple trees, owing to the softness of their wood. Next, after them, the willows probably suffered most. In many places in the county willow hedges by the roadside were bent over until the trees nearly touched the ground and numbers of the trees were either broken short off or lost many of their branches. Hedges running east and west were worse affected than those running north and south, owing to the general tendency of the trees to bend toward the north. Hence in the former case the trees, having no support, were broken down by the ice, while, in the latter, they rested upon each other to some extent, and were saved from breakage. Box elder trees were badly damaged and elms were damaged almost as badly. Some handsome box elder trees in the town of Greenfield were almost ruined. A handsome weeping willow tree in Greenfield was literally stripped of all its smaller branches, not one being left unbroken. The accompanying illustration was taken of it just after the removal of the broken branches and may give some idea of how thoroughly the storm did its work. Oak, walnut and hickory trees resisted the ice well and were largely uninjured by it. Cottonwood trees suffered severely. The amount of damage done to trees was largely determined by their position and habit of growth. Trees which grew Iowa Academy of Science. Weeping- Willow Tree at Greenfield Stripped by Sleet. IOWA ACADEMY OF SCLENCES. 65 upright shed the water and sleet well and were not greatly injured, while tliose which grew in a slanting position or were gnarled and straggling in their growth, did not shed it so well and consequently received greater injury. Limbs growing in a horizontial position were soon weighted down and broken while those more nearly vertical were saved. In the native timber much damage was done and many trees were ruined, but the damage was not nearly so great as in the artificial groves, owing, doubtless, to the fact that the native timber tends naturally to grow in the best sheltered places and in such a manner as to protect itself, while, of the artificial groves, many are planted in exposed positions and in such a manner as to offer little resistance to a storm of this kind. In many of these groves the trees have been planted so close as to mutually choke each other, and consequently show a tendency to grow very tall, with a thin, spindling trunk and no branches lower than twenty or thirty feet from the ground. Wherever this condition prevails the damage done by the storm was very great. Throughout these groves we may see any number of shattered and maimed trees — evidences of the fact that the stunted trunks were unable to support the heavy masses of sleet which hung to the limbs. Trees which had distanced their comrades in the struggle for light and air by pushing up some distance above them suffered most severely and were almost invariably either broken off short or lost many limbs The fact that most of the artificial groves are of soft maple trees also goes far to explain the great dam- age which they sustained. Trees growing in the open, as a rule, showed a better and stronger development than those in groves, and, hence, better ability to resist the storm. In the case of most groves there is a very evident tendency on the part of the trees to lean toward the northeast — a ten- dency which has never been very satisfactorily accounted for, but is usually credited to the prevailing southwest wind of summer. This fact was emphasized by the results of the storm. An examination of almost any grove which suffered from the storm would reveal the fact that the greatest damage was done on the north and east sides and that, as a rule, the broken trunks and branches fell outward, while on the south and west they fell inward, or toward the center of the grove. 66 IOWA ACADEMY UF SCIENCES. Naturally, the trees ou the south and west were, to some meas- ure, supported by those within, while those on the north and east, having no such support, succumbed to the sleet. A like effect may be noted in the case of trees in isolated localities, and in hedges. In hedges running east and west the greatest breakage was observable on the northern side— especially in the case of willow trees — whose leaning habit of growth made them particularly susceptible. In hedges running north and south the damage was not so great nor the effect so well marked, but here, as a rule, the greatest breakage was on the east. However, although these conditions were so general as to be readily observable, there were many apparently iaexplic- able exceptions, but in the main the effects of the storm were as here given. THE AUGUST CLOUD-BURST IN DES MOINES COUNTY. BY MAURICE RICKER. It is my purpos to give merely a statement of facts con- cerning the storm which deluged Des Moines county the morn- ing of August 16, 1898. I believe it was the heaviest rainfall ever noted in the United States for the period of its duration, and while the area covered was not large, it proved to be very destructive. No doubt there have been storms in which the precipitation was as heavy, where no one saw fit to chronicle the event. Many great disasters, as the Johnstown flood, witl- a greater area and less precipitation, have become historic because of loss of life. My attention was called to the excessive rainfall that morn- ing at daylight by the little swollen creek which divides South from West Hills in the city of Burlington. Yet this was in 'the very edge of the storm. The newspapers contained many sensational stories of narrow escape from loss of life, damage to county, city, railroad and farming interests. I read these with no special interest and dismissed their estimates of six- teen to twenty inches of rain in Flint valley as exaggerations so commonly found in popular accounts of natural phenomena. As soon as the tracks were repaired I had occasion to make lOWAcACADEMY OF SCIENCE. Soft Maple near Greenfield Broken by Sleet. IOWA ACADEMY OF SCIENCES. , 67 many trips by rail through the tiooded district. The terrible strength of the water flow then became apparent and, noting the limited drainage area of Dry Branch in particular, I began to take more interest in the event, believing at this time that the real precipitation must be about five or six inches. I have since made a thorough canvass of the county and record for those interested in these phenomena only those things wh'ch are beyond dispute. At 10 o'clock on Monday night, August 15th, it began to rain. The precipitation was not extraordinarily heavy, and while it rained steadily no one noticed that there was anything unusual about it. According to good authority, the so-called cloud-burst began about 2 o'clock a. m. and ceased shortly after 4. It rained more or less for an hour later, however. A liberal esti- mate of time for the heavy rain is three hours. The precipita- tion outside of these three hours, from all accounts, could hardly have been more than two inches. The area of heavy rainfall can be approximately bounded on the south by the divide betw^een Spring creek and Flint river. The former stream was not out of its banks. Keokuk reports a trace only. The county line forms a close boundary on the west, Yarmouth being in the edge of the heavy rain, but suf- fered only from lightning. Washington reports 1.72; Iowa City, .40. The north boundary of very heavy rain is not far above the county line, Wapello reporting 5.16. On the east, the river was the boundary for excessive rain, although the precipitation was heavy as far east as Biggsville, 111. This maps out two-thirds of Des Moines county, or approximately 250 square miles. The Flint river and its tributaries drain one-half of this area. Dry Branch, Yellow SjDrings, Dolbee and Swank creeks drain the remainder, save a strip of three miles in width, which drains north into Louisa county. Dry Branch drains only about eleven square miles, yet its waters caused much damage. Yellow Springs creek drains a much larger area and carried, perhaps, more water, proportionately to its bed, than Dry Branch. It is not easy to estimate the rainfall accurately. There were no rain gauges in the county at this time. I shall give some of the reports as I obtained them. Great care has been taken to get accurate and truthful accounts in this phase of the investigation. (5S IOWA ACADEMY OF SCIENCES Mr. J. W. Merrill, editor of the Mediapolis New Em, vouches for this story: A large circular windmill tank, with nearly straight sides, stood removed from bui dings upon level ground. It had never been used as a tank and was dry Monday night. It had a semi-circular cover, which was open, exposing one- half the tank to the rain. The water ia the tank measured twelve inches in depth on Tuesday morning. We will grant that some of the water in the tank ran in from the half which was covered. Yet. had it all run in — and it could not — there would have been a rainfall of twelve inches. If the tank had been perfectly level, would more than one-half the water which fell on the cover have entered the tank? In Dry Branch valley, below Latty, six miles south, lives a member of the county drainage board, a man whose judgment can be relied upon. He states that on Monday night an empty, straight-sided tin can which was used for mixing spray fluids for fruit trees, was left in open ground. The can was about fifteen inches in diameter and sixteen inches high. At 5 o'clock the can was full and running over. North of West Burlington lives a truck gardener, who left standing in the garden several sprinkling pots, whose open tops are half covered with tin in the usual manner. These ought to have shed one-half the water, yet daylight found them all with eight or nine inches of rainwater in them. Other less reliable cases have come to my notice, where the hole of a barrel becomes the outlet for overflow, etc. The instances given suflice to show the character of the informa- tion which leads me to firmly believe that over an area of fifty square miles at least sixteen inches of water fell in three hours. The instances of incredibly rapid rise in streams, even when already in the flood plains, seem to corroborate the estimates given above, while the records at the Mississippi bridge at 6 p. M., August 16th, show a stage of four feet five inches, a rise of three feet two inches. When we remember that local rain seldom affects the stage of water noticeably, and take into account the limited area of the storm, we must readily see that something extraordinary must have happened. The rain extended some distance up the river, it is true, Clinton report- ing 8.01, Davenport 2.20. The erosion was well in keeping with the figures given for rainfall. Little idea can be conveyed of ihe force of the water. IOWA A CADE .VI Y OF SCIENCES. 69 which tore up trees twelve inches in diameter and floated rocks weighing hundreds of pounds many feet from their former location. Hay stacks were floated bodily against steel bridges, carrying them many hundred yards down stream. In the city of Burlington whole timber piles floated from the yards and blocked the entrance to the great sewer Wagons and farm machinery of all kinds went down the Mississippi river, together with many dead animals. The oldest settler had never seen the water so high in these valleys. Many houses, barns, sheds, etc., were flooded, and this in spite of the rapid fall of these streams, which here brealc through the escarpment to the Mississippi. The upper valleys broaden out with many fertile flats, often planted in truck and garden produce. The lower stream has low banks through the flood plain of the Mississippi. The rush of water necessarily did very great damage to both crops and soil. In many cases acres of ground which had been fall plowed were denuded of soil and left covered with sand and pebbles. Flint river, which formerly entered into O'Connell slough after paralleling its course for half a mile, cut a new channel directly through cornflelds to the slough, tearing out acres of soil with crops and timber. A raft of logs belonging to the J. D. Harmer Manufacturing company went down before it like straws. O'Connell slough, which had been the storage place for logs in summer and steamboats in winter, was piled with the debris, which will cost |115,000 to remove unless the ice and high water next spring can scour it out. Manufacturing establishments situated upon the slough will otherwise be cut ofl from navigation. Hawkeye creek, a covered sewer through Burlington, became clogged with floating lumber and caused much damage to lumberyards, a foundry, the pickling works and the Murray Iron works. The stone apron at its mouth went out. The clearing of the sewer and the rebuilding of the apron will cause the city's heaviest bill for damage. The county lost twenty-three bridges, some of which have been replaced at an immediate outlay of ^16,000. The Burlington, Cedar Rapids & Northern railway lost nearly two miles of track and five bridges. The bridges which replaced the lost ones are fine steel spans, much better than the old ones, costing $30,000. The loss to land owners is hard to estimate, but must have 70 IOWA ACADEMY OF SCIENCES. been very heavy in crops and damage to soil. The loss of live stock drowned would probably have been almost as heavy had it occurred in daylight, owing to the very rapid rise of the streams. The estimate of $100,000 total loss is not far from correct. There are oaany other interesting features which should be written up. The weather conditions can be obtained from the weather bureau. The map for the date shows a low reaching into Iowa, but would not warrant a forecast of general rain The energy liberated by so heavy a fall of rain would form an interesting study. I have collected some data concerning similar storms in previous years. The heaviest fall that has come to my notice was fifteen inches, at Wilmington, Del., on the 29th of July, 18 i9. THE BURLINGTON ARTESIAN WELL. BY FRANCIS M. FULTZ. Work was commenced on the Burlington artesian well about midsummer of 1896; but, owing to cessation of operations for somewhat more than a year, it was not finished until midsum- mer of 1898. The well is located in Crapo park, and the expense of putting it down was borne out of the park funds. It was expected that a flow would be reached in the St. Peter sandstone at a depth of about 900 feet. This belief w^as based on the flow obtained at the Ft. Madison and Keokuk wells, south of Burlington about twenty and forty miles respectively. As will be seen from the subjoined section the St. Peter was reached at a depth of 950 feet. No flow was obtained, but the water rose to within thirty-eight feet of the surface, and indicated a strong supply. There was no further change of the head of more than a foot or tw^o, although the drilling was carried down to 2,430 feet and passed through at least two other water-bearing strata. The diameter of the well is six inches for 1,700 feet and five inches for the balance. No casing is used excepting through the loess and drift. At 1,700 feet a test was made of the capacity. Over 100,000 gallons were pumped out daily for one IOWA ACADEMY OF SCIENCES. 7[ week, with no appreciable lowering of the head. At 2,430 feet, where the work was stopped, the pump was again put in and over 100,000 gallons were thrown out daily, for ten days, without lowering the head. No analyses of the waters have yet been made. The water pumped out after the drilling was stopped, and which was probably composed of a mixture from the different levels, was clear and sparkling and remarkably free from objectionable mineral tastes. It was slightly diuretic and laxative. No extended experiments have as yet been made in using the water for park irrigation, which was one of the main purposes in putting down the well. It is hoped that the supply will be great enough to feed an artificial lake and a fountain or two. The pumping will probably be done by electrical power. Through the kindness of the Tweedy Brothers, who carried the drilling down to 1,700 feet, and the Wilson Brothers, who finished the work, a very complete series of samples of the drillings came into my possession. From these, glass tubes have been filled, one being placed in the public library and another in the high school at Burlington, each showing, approximately, a complete section of the well. At four different levels the drillings were washed away by the pressure of the water from below, the material doubtless finding its way into crevices through which the well passes at higher levels. There were four of these intervals when no samples were obtained, the first at 1,475 feet, and continuing for forty-four feet; the second at 1,630 feet, and continuing for forty feet; the third from 1,725 feet to 2,000 feet, making a long interval of 275 feet; and the fourth from 2,360 feet to 2,400 feet, equal ing forty feet, making 400 feet in all from which no drillings Avere obtained. The surface at the well is 685 feet above tide. Loess and drift Limestone and cliert, driUing-s coarse Limestone, much less chert, driUing-s finer. Limestone, light buff, fine grained Limestone, yellowish, sandy, cherty Shale, sandy, with some lime IOWA ACADEMY OF SCIENCES. Shale, light blue Shale, dark blue Limestone, compact, gray Shale, gray Shale, light blue Sliale, brown Dolomite, brownish gray Dolomite, dark gray, coarse grained Dolomii e, gray Dolomite, pinkish gray, coarse grained. Dolomite, light brown, coarse grained.. Shale, dark, slightly petroliferous Shale, dark, dolomitlc Dolomite, with some little chert Dolomite gray Dolomite, white Sand, pinkisli Sand, mixed with black shale Sand, clean, white, finegrained S ind, clean, wlilte, coarse grained Sand, darker, coarsegrained Dolomite, white, compact Dolomite, pink, compaci Dolomite, pinkish gray, compact Dolomite, pinkish, compact Sand, rusty, with some lime and chert.. Sand, rusty Sand, very sharp grained Sand, finegrained Dolomite, white, compact Dolomite, with brownish shale Sand, mi.xed with limestone and chert . Uhert, white Sand, fine grained, with some shale and limestone. Drillings •.vished away Sand, biown, rusty Limestone and chert, whitish. Sand, limestone and chert Dolomite, grayish-brown.. . . P ' P- 126 275 165 440 140 580 38 618 20 ' 638 50 688 49 737 78 bl5 IOWA ACADEMY OF SCIENCES. Holomite, light gray Limestone, light gray, with some chert Hnd saud. Drillings wastied away Sand, clean, white Dolomite, yellowish, sandy Drillings washed away Limestone, dark gray, do'omitic. Limestone, dark gray, nearly pure Limestone, dark gray, arenaceous Dolomite, dark gray, aren«ceous Dolomite, rusty gray, with sand and shale Dolomite, rusty gray, mixed with pure llmestnnp. Dolomite, rusty gray, with much pure limestone. . Limestone, dark gray, with some little sand Limestone, mixed witb sand and shale Limestone, brownish gray, with much sand Sand, light gray, with some lime Sand, light gray, dolomitic Sand, white, fine grained Sand, rustv. coarser grained Drillings WHshed awHy Sandstone, very hard {li hours in uri ling 5 feet), mnuy ninki«-h grains resembling quartzite; mixed with much sba.e and dolomite from above Same as No. 4, but with some little slate Slate, very dark, compact Slate, same as No. 2, but harder Drill stopued in pure slate, at 2,430 feet. SUMMARY. a z 66 64 65 62-63 59-61 55-58 50-54 48-49 45-47 FORMATION. Pleistocene Augusta— Uppfr Burlington Augusta— Lower Burlington Kinderhook Devonian Silurian Maquoketa Trenton IOWA ACADEMY OF SCIENCES. Number. FORMATION. B a. O 40-44 36-39 St. Peter Upper Oneota 145 250 60 22 968 10 20 1100 1350 33-35 New Richmond 1110 30-31 5-29 St. Croi.x ''400 3-4 1-2 Sioux Quartzte (V) Primitive (?) 2410 2430 In the discussion of this paper Mr. Leverett called attention to the need of careful examination of the suposed Sioux quart- zite drillings, especially since a well at the neighboring town of Aledo, 111 , reached a depth of 3,100 feet without touching the quartzite. THE LOWER RAPIDS OF THE MISSISSIPPI RIVER. BY FRANK LEVERETT. INTRODUCTORY. In the early days of navigation on the Mississippi, two important rapids were found to interrupt the passage of ves- sels at low water stages; one, about fifteen miles in length, being above the city of Rock Island, 111., and the other, about eleven miles in length, above the city of Keokuk, Iowa. These became known, resj^ectively, as the upper and lower rapids The latter are also called the Des Moines rapids because of the situation above the mouth of the Des Moines river. In both rapids the obstructions consist of rock ledges, yet the form of arrangement of the ledges is not the same. The upper rapids consist of a succession of rock barriers called "chains," each usually but a fraction of a mile in breadth, which pass across the river channel and are separated by pools or stretches of slack water. The lower rapids are more uni- form, there being a nearly continuous descent across them. The rate of descent, however, varies, as shown below. In open- *Published by permission of the director of the United States Geological Survey. IOWA ACADEMY OF SCIENCES. 75 ing the upper rapids to navigation it was necessary only to cut channels across the barriers, while in the lower rapids a canal has been constructed.* The precise length of the lower rapids is 11.1 miles, the head being at Montrose island and the foot a short distance above the river bridge at Keokuk. The total descent is 22.17 feet, or very nearly two feet per mile. The rate of descent is greatest in the lower part, there being a fall of about four and one-half feet in the lower mile and nearly eight feet in the lower two miles, f Above this part the fall, though not uni- form, is less definitely broken into rapids and pools than in the upper rapids. Indeed, there appears to be a rock floor forming the river bed throughout the entire length of the lower rapids. Immediately above the head of the lower rapids a deep, pre- glacial channel appears, whose floor, as shown by several bor- ings, is 125 to 135 feet below the low water level of the river. This is filled mainly with blue bowlder clay up to about the level of the river bed. Sand, however, in places, extends to a depth of nearly sixty feet below the surface of the river at low water, as shown by the bridge soundings at Ft. Madison and Burlington. A pool extends from the head of the rapids up to the vicinity of Ft. Madison — nine miles. The depth of the pool in places exceeds twenty feet at low water stage, thus extending to about that distance below the level of the rock surface in the river bed at the head of the rapids. Below the rapids the river for four miles is in a narrow valley in which the depth of the drift filling is not known. It there enters a broad, preglacial valley, which has been found to constitute the continuation of that occupied by the river above the rapids, and which no doubt was excavated to a cor- responding depth, though as yet no borings have been made ♦Phis consists of a channel blasted out of the rock for a distance of three and one- quarter miles from the head of the rapids, beloiv which a retaining embanlly{/!/ra inultilineata is there often found on high grounds, and then appears as a stunted form, like that which is common in the loess. The loess-fauna, of Council Bluffs, is thus not only wholly terrestrial, but, with the exceptions noted, is almost identical with the modern upland fauna of the same regions. Surely no conditions of excessive moisture prevail in that region to-day. Yet a recent writer,* referring to the loess of the Missouri region, says: "In the Bluff loess more than nine- tenths of the total number of individuals belong to species that are found only in unusually damp situations. The species having an optimum habitat that is not excessively moist have not been observed to occur abundantly in the Bluff loess.'' Another interesting fact noticeable in the exposures of loess, at Council Bluffs, is the occurrence of the great majority of the fossils in a more or less distinct stratum which varies (so far as observed) in altitude from about eighty to at least 200 feet above the river-valley, and which follows in general the contours of the present surface, but with a less convex curva- ture. (In exposure N it seems to be a continuation of the shell-bearing layer in E, yet it is at least 100 feet higher. In exposure M it drops about eighty feet in a block.) Its limits are not sharply defined above or below, and it varies in thick- ness from about six to at least twenty feet. Overlying it is a deposit of more or less laminated loess-clay, which is usually non-fossiliferous, and which varies from a few to more than thirty feet in thickness. When fossils occur in this upper stratum, they are few in number and widely scattered, f *C. R. Keye<— Am. Jour, of Sci., (4), Vol. VI, p. 304. +At the base of the bluff in exposure K, what seemed to be a second sheU-bearing' layer was observed about sfventy-five feet below the main fossiliferous band. The section, however, was more or less obscured, and the mass may have slipped from the bluff above. The fossils in column K. in the table, are from this stratum. It will be observed that they are ordinary forms which are abundant in the main she'l stratum. 108 IOWA ACADEMY OF SCIENCES. The presence of this shell-bearing stratum suggests that for the period during which it formed the surface soil, and while it was slowly accumulating, the conditions in this particular locality were more favorable to the growth of land-snails than now. There was, probably more vegetation, and hence the surface was not so frequently storm-swept as at present. This does not necessarily signify that general climatic conditions were different, but that these particular banks or bluffs w^ere more heavily timbered, with the Missouri river, probably flow- ing at its base, its surface conditions being similar to those of many timbered hills and knolls between Omaha and Nebraska City, west of the Missouri. It is interesting to note that between Iowa and Nebraska, the Missouri river now flows along the western side of its broad valley, and that the adjacent western bluffs are more heavily timbered and contain all the living species of molluscs herein recorded, with the exception of Nos. 1 and 16, while the more remote eastern bluffs are more barren and rugged. The shell- bearing band may simply represent the period during which the river in its shif tings occupied the eastern part of the valley. The foregoing facts lend support to the seolian theory of the origin of the loess, as is shown by the following considerations: First. — The general manner of distribution of the modern and fossil molluscs is essentially the same, this fact indicating that they were not carried by waters, but w^ere quietly buried in dust. Had they formed a part of river-drifts, they would be more frequently heaped together, — not scattered as we find them in the loess — and fluviatile shells would be more or less intermingled. Moreover in many years' experience in dredg- ing in ponds and streams, the writer has seldom seen a land- shell which had been carried with the finest sediment into ponds or lakes though such shells are sometimes found in sand and other coarse material. Currents of water which could carry most of the shells now found fossil, would also carry coarser material than that which makes up the loess. Another fact which bears out this conclusion is the presence of opercula in fossil shells of HeUcina occulta in the northern loess and Helk-ina orbiculata in the southern loess. As the operculum so readily falls from the decaying animal, it would scarcely remain in place if the shell had been transported any distance. Second. — The occurrence of fossiliferous loess chiefly in the IOWA ACADEMY OF SCIENCES. iQy vicinity of streams is consistent with the tlieory of loess-forma- tion presented by the writer before this academy.* Plants, and especially forests, develop chiefly and prima- rily along- streams. This creates conditions favorable to land- molluscs, and at the same time forms a trap for the dust, carried from adjacent, more barren regions. The occurrence of loess in the eastern part of Iowa, chiefly along the border of the lowan drift sheet, may also be explained on the same ground. After the melting of the ice, the terminal moraines offered the first lodging-place for plants. Here, forests early developed, and the conditions for entrapping the dust from adjacent, less- favored territory, which was probably dry during a part of the year, were here first developed We are in the habit of describ- ing the lobed ridges of loess-regions as characteristic of loess topography, yet they are quite as much characteristic of some drift-areas; for example, along the Big- Sioux river in Iowa and South Dakota. In eastern Iowa the surface of the loess is largely shaped by the underlying moraines, which first presented conditions suitable to the deposition of the loess, and where, consequently, the deposit is best developed. The loess at Natchez does not show this " loess -topography in the same degree " Third. — The depauperation of some forms of shells, and the presence of others which are normally inhabitants of dry regions, suggest a climate sufficiently dry that, during a part of the year, at least, clouds of dust could be taken up by the winds. Fourth. — The overwhelming preponderance of land-snails in the loess must always be borne in mind. This, however, does not prove that the loess regions were entirely devoid of lakes and streams, but rather that the loess proper was deposited chiefly upon higher grounds, for, if by any agency fine material was uniformly deposited over all of Iowa to-day, covering the successive generations of our present molluscan fauna, there would be a much greater proportion of aquatic and moisture-loving species than we find anywhere in the loess. Fifth. — The amount of material carried by the winds need not have been so great as is sometimes assumed. The estimate made by the writer f for the rate of deposition for east- ern loess (1 mm. per year), and that made by Keyesl *Proc. Iowa Acad. Sci., Vol. Ill, p. 83 et seq. tProc. Iowa Acad. Sci., Vol. Ill, p. 88. :::Am. Jour, of Sci., (4), Vol. VI, pp. 301-303. 110 IOWA ACADEMY OF SCIENCES. for western loess (one-tenth to one-fourth of an inch) would be sufficient to form most of these deposits respec- tively in the 8,000 years, usually computed, since the reces- sion of the glaciers. The objection made by Doctor Chamberlin* that " the eolian deposits are measured, not by the quantity of silt borne by the winds and lodged on the surface, but by the difference between such lodgment and the erosion of the surface/' is met, at least in part, by the theory offered, for it is a well-known fact that timbered areas, even when very rough and with abundant slopes, are scarcely eroded by even the most violent precipi- tation of moisture. Professor Udden's recent admirable reportf also bears on this question, and should not be over- looked by the student of loess- problems. Sixth. — No distinction can be made between the origin of eastern and western loess. The finer quality and lesser thick- ness of the former rather suggest that there had been more moisture (/. e., a shorter dry period during each year) and, hence, less dust; that the winds were less violent, and -that there were greater areas completely covered with vegetation, this resulting in the necessity of transporting dust much greater distances, which would therefore be finer. J It should be borne in mind that the above noted differences between the regions in question actually exist to-day. There is more rain, — there are larger areas closely covered with vegetation, and less violent winds prevail in eastern Iowa and eastward, — and considering the position of mountain chains and seas, the same differences must have existed for a long time. That they did exist, during the deposition of the loess, is also indicated by the proportionately somewhat larger number of species in the eastern loess which prefer or require moist habitats. But the fauna of the eastern or Mississippi river loess is essentially a terrestrial fauna. The great fluviatile groups, now everywhere common in the streams of eastern Iowa, are wanting in the loess, and the few fossil aquatic species are such as to-day prefer ponds, and are often found even in those which dry up during the summer. It may again be emphasized that the fossils show no greater difference, between the surface conditions which existed during the deposition of the loess of the eastern and western parts of * Jour, of GeoL, Vol. V, p. 801. tThe Mechanical Composition of Wind Deposits. 1898. •fSee Udden, I. c. pp. 56, 57 and 67. IOWA ACADEMY OF SCIENCES. Ill Iowa, than exists to-day between the surface conditions of the same regions. This fact is irrefutable, and must not be over- looked in any discussion of the conditions under which loess was deposited. TABLE OF SPECIES.* A 5 10 3 55 157 12 6 c 210 12 ■76 + :f 63 3 D 5 '2 i E 5 1 F 81 8 16 17 G 17 '4 2 H "89 21 ii 1 ■3 ' i I 9 J K L 12 1 io M 14 1 N 0 P- .. 2 Q '2 ■3 1 15 1 '3 S ;!i ' i T 1 14 3 6 ■4 3 1 06 "■ 2 Vallonia graciliconti Beihn Vallnnia iiarvula Sterki 45 ■3 12 1 'i2 -.8 i 4 5 6 Vallonia perspectiva Sterki Polygwa multilwata (Say) Pils . 8 q Poly'uura hirmta (Say) Fils Polygura leai (War.i; Pils f^trohilnps oirg'> Pils 1 4 8 35 5 i ii ■2i 280 ::: ::: 127 10 11 12 13 14 15 16 17 LeuchocMla fiiUax (Say) Try .... Bifidaria nrmifera Say) St Bifidnria cont.racta (Say) St Bifidaria holzingeri (Sterki) St. . . Bifidaria curvidens (GUI.) St Bifidaria p'ntndon (Say) St Pupa blandi (Morse) Blnn Vertigo boltesiana Morse 18 Cnchlicopa liibrica (Miill) P. & .1. Vitrea hammoni>i (Strom) P. & J. Vitrea indentata (Say) P. & .1 1 2 4 3 27 10 1 1 12 10 235 i 2 58 1 32 3 "i 12 3 2t* 5 279 11 3 18 -- 19 1 1 ■■5 10 24 13 250 14 4 4 ?i 09 Zonitoides aiboreus (Say) St Zonitoides shimekii (Pils) P. & J. II . Zonitoides rninusculus (Binn.) P. & J 3 1 1 6 3 15 4 4 20 18 m 21 6 19 46 6 935 16 ■3 8 i 10 2.i 21 1 i 3 3 2 ■ i 15 5 ^5 Pyramidnlanlternata (Say) Pils. . Pyramidula striatella (A.nth.) Pils Helicodiscus lineatus (Say) Morse Succinea obliqua Say^ i Succinea grosvenorii Lea (' Succinea avara Say tgg-of a land snail 26 27 28 29 30 31 21 1 4 12 3 4 5 i 3 *The nomenclature of Pilsbry and Johnson's recent Catalogue' of the Land Shells of N. Am is here employed. As there are some departures fpotn former usage, the changes are here noted: Species 2, 3 and 4 were formerly included uader V. puj/ihella. Species 5 and 6 were referred to the genus Memdon, and 7 and 8 to Stenotrema. Species 9 was included under Stro/ufi labyrinthica. The species of Leachochila and Bifidaria were included in Pupa. Species 18 was called Ferussacia subcylindrica. Vitrei, Conulus and Zonitoides were formerly placed in the genus Zmita, and No. 19 was called Zonitoides radiatulus. Pyramidula was formerly Patula. Succinea grosvenorii was called S. lineata. +Oae specimen of P.profun'ix was found by the writer in exposure C (since con- siderably altered) in 1890. 'i^Three specimens of this species were collected in exposure 0 in 1890. IIThe writer formerly regarded this as a form of Zon. nitidus. Mr. Pilsbry, however, regards it as distinct, and in deference to his oplnioQ his name is retained. TThe form of S. obliqua which occurs most commonly in the loess is the narrower, smaller form with more extended spire, such as is not uacommon (living) in Iowa and as far east as Indiana. As itis difficult to distinguish between some forms of this and &'. grjsvenorii, the two species are not here separated, as more time for careful compari- son of the large sets will be required. 112 IOWA ACADEMY OF SCIENCES. NOTES AND EXPLANATION OP MAP. THE EXPOSURES ARE REPRESENTED BY HEAVY LINES. Exposures A R and C. These were cut out of the same ridge in street- grading. The shell-bearing stratum shows well on the east, north and Fa I R M 0 U N 7 Pa R K A MO VICINITY Council Blu f fs Ja. west sides of C. It is about twelve or fifteen feet thick. Above it there is a layer of clay about fifty feet thick and almost entirely devoid of fossils. IOWA ACADEMY OF SCIENCES. 113 Exposure D. The shell stratum is not so rich in fossils as in C. Above it tbere are fifteen or twenty feet of clay, in which a few Succineas were found. In the clay below the shell stratum there are several distinct, bu"- irregular, bands of lime nodules, — some vei'y large. Expofure E. Very similar to />, but with only one band of nodules. Expamre F. Fossils are vcy abundant in the shell stratum, which can here be traced for three or four rods. The shell-less loess above is eight or ten feet thick. Exp^'sures (V, H, I, -land K. These exposures were all formed from the same ridge, by deep cutting and grading. The shell stratum is distinct in all of them, and, as in all other sections, it follows in general the contour of the surface. It varies in thickness here from six to twenty feet. It is by no means equally fosslliferous throughout. Exposures L and 31. . Those were formed by the grading of High School avenue. The street slopes westward from the high school, and drops about sixty feet in a block. On the north side tlie shell stratum is nearly parallel to the street grade, and but little above it. On the south side it dips b -low the street about half-way down the slope. Exposures N, O, P, Q. B, S and T These are all exposures along the road which winds eastward from the Tenth avenue entrance to Fairmount park At N the road is about 1J"5 feet above the river valley, and the shell stratum (which is here very rich in fossils), extends about three feet higher. It dips down toward the west at such an angle that it would connect with the shell stratum at E, which is about 100 feet lower. 'J he same layer may be traced, more or less indistinctly, to O, where there is a cut about twenty feet deep. The shell stratum rises to abour eight feet above the roadbed (here about 200 feet above the river valley), but fossils are not abundant. The remaining exposures along this road are formed by the road cutting ti-e smaller lateral lobes of the greater ridges. The letters apply to the extent of road from bend to bend, not to individual exposures. At the southern bends in the road are the high points, the road sloping down to near the bases of the ridges to the north. Fossils are found ia most of the little expos- ures (which, in but few cases, exceed fifteen feet in height) along the road, but they are nowhere as abundant as in some of the exposures along the bluff fronts. The exposures which are represented on the map, but not lettered, are non- fosslliferous. THE IOWA LIVERWORTS. BY B. SHIMEK. Among the groups of plants hitherto neglected by Iowa botanists, the liverwot-ts are by no means the least interesting. A few of the large thalloid species have long been familiar objects to botanists working in ottier fields, but the general lack of economic importance of the group, and the habits and small size of most of the species, no doubt account for the fact that they have attracted less attention than they deserve. In general, the liverworts prefer moist places. They may 114 IOWA ACADEMY OF SCIENCES. be found upon mud-fiats, upon dripping rocks, on moist lime- stones and sandstones, on the bark of trees, on old logs, in tangled mats of moss, and other similar habitats. But not infrequently they flourish on rocky ledges and sandy or clayey tracts, which are dry and barren during the greater part of the summer. Their power of re-ju venation, however, almost equals that of their near kin, the mosses, and moisture almost instantly revives them, — a fact of much interest to the student of these forms, for dry, unsightly material collected during the most unfavorable seasons of the year, may be rendered fit for study in a few moments. The following notes on twenty -one species are offered not as a complete and exhaustive report on the Hepaticce of Iowa, but rather as an introduction to this, in Iowa much-neglected, group, with the hope that interest -in it may be aroused, and the way paved for a full account of our species and their dis- tribution,— for the list will no doubt be materially increased. Although its nomenclature is not always strictly correct, the sixth edition of Gray's Manual is followed for convenience, because of its general use. Unless otherwise stated, the material upon which this report is based, is deposited in the herbarium of the State University, and was personally studied by the writer.* Unless special credit is given, the specimens were collected by the writer, Mr. T. E. Savage assisting at Wildcat Den, Muscatine county, and with Mr. P. C. Myers on Muscatine Island, Louisa county. Order Jungermanniace^. Friil/(nii(i viiY/hiica Lehm. On the bark of trees, usually near the base, on low grounds, Muscatine Island, Louisa county; not common. F. ebor<(ce)isi!^ Lehm. On the bark of trees, near base, in Johnson and Louisa counties, and on both bark of trees, and sandstone, in Wildcat Den, Muscatine county; very common; also reported from Story county by Bessey.f F. (eolitis Nees. On sandstone, in Wildcat Deii, Muscatine county; not common. F. s(/uarrom Nees. Common on limestone bluffs at Iowa City, and at Ft. Dodge. ♦Prof. L M. Underwood kindly assisted in a few of tlie earli-^r determinations. (Bull. la., Agric. Coll., Nov., 1884. IOWA ACADEMY OF SCIENCES. 115 Porella p'mnata L. Thus far collected only in Jackson county, in 1896. P. i^latyphiiUa Lindb. Very common on mossy banks, etc., at Iowa City, Mason City and Ft. Dodge; also near Decorah {P.C. Myers.) Reported from Story county by Bessey (/. c). PtUidiuiii ciliare Nees. On rotten logs; Iowa City; not rare. Lophocolea heterophiji/a Nees. Very common on mossy banks near Iowa City. GhiloscyphuH polyantlios Corda. Common in moss on moist banks, rotten logs, etc. ; Iowa City, Ft. Dodge, and Wildcat Den, Muscatine county. Juiuie una u Ilia ventricosa Dicks. On moist banks; in moss at Iowa City and Ft. Dodge, and on Anthoceros in Muscatine county, along the Cedar. Also collected at Iowa City by Miss Linder. Blasia pusilla L. Abundant on dripping rocks at Wildcat Den, Muscatine county. Order Anthocerotace.'E. Anthooeros kcvis L. On wet clay-banks, Johnson county. Also collected by Miss Linder. Not common. Also reported from Story county by Bessey (J. <■ ). A. punctatus L. Oa low, wet banks in Muscatine county, along the Cedar river. Order Marchantiace.e. Marchantia polymorpha L. Usually on rather moist banks and slopes, — sometimes on hard- beaten soil and cinders, as along the streets of Iowa City. Common at Iowa City, Mason City, and Fores ■ City. Also, Emmet county {R. T. Crafty) and Decorah {P. C. Myers). Reported from Story county by Bessey (/. c). C'onoreplirilHs ronicus Dumort. Very common on moist banks at Iowa City, and not uncommon in Muscatine and Louisa counties. Also at Decorah (P. C. J/?/(^y.s). Reported from Story county by Bessey {1. c). Grhnaldla barbifroiis Bisch. Common on rocky banks and bluffs; sometimes in very barren places. Johnson, Linn, Mus- catine, and Lyon counties. A.stereUa hemlspluerica Beauv. Not rare at Iowa City, on mossy, rocky banks, etc. Lumdaria vulgaris Raddi. Introduced. Formerly common in the hothouse at Iowa City. Never fruiting here. 116 IOWA ACADEMY OF SCIENCES. Order Ricciace^. Bk'ckt frostii Aust. Not common on mud- flats on Muscatine island in Louisa county. R. lutescens Schwein. Very common on mud-flats on the Mississippi bottoms below Davenport, and on Muscatine island in Louisa county. B. flultans L. Common in ponds and on mud at Cedar Rapids, Forest City, near Davenport, and on Muscatine island in Louisa county. Also in Emmet county {11. I. ('ratty). A SIMPLE INCUBATOR. BY L. S. ROSS. No claim of originality is made in the presentation of the description of the simple apparatus used by me as an incu- bator. The idea, so far as I know, originated in the mind of Mr. W. D. Frost, assistant instructor in bacteriology in the University of Wisconsin. The incubator consists of a drygoods box, lined inside and out with asbestos paper, set on a galvanized iron base, and divided by wire netting into a convenient number of shelves. Heat is obtained from a rose burner, and is regulated by a thermostat made in the laboratory. The box I used is thirty-three inches long, nineteen inches wide and twenty-six inches from front to back. The cracks were stopped with rags and then the asbestos paper was pasted on the w^ood. A door was cut in the front, a window in one side and one in the door. The door is 25x13 inches; the side window is 9x8 inches, and the one in the door is 12x6 inches. A galvanized iron pipe, three inches in diameter, open at the lower end and closed or opened at the top by a circular cut-ofl", passes through the box from the base and projects six inches above the top. A hole, three and one-half inches in diameter, is cut through the center of the lower end of the box and the iron base, leaving only one thick- ness of asbestos paper between the chamber containing the burner and the lower compartment of the incubator. This hole may be closed by a galvanized iron slide. The incubator is divided into three compartments, the lower two of which are Iowa Academy of Science. A Simple Incubator. IOWA ACADEMY OF SCIENCES. H" each ten inches high and. the top one eleven inches, the shelves being of one-fourth inch mesh galvanized iron wire netting. In the top compartment is the heat regulator, which consists of a 100 cc. flask for a bulb, and a one-fourth inch glass tube with a double bend, to contain liquid and to receive the gas. One end of the tube passes through a rubber stopper into the flask, while the other end receives a smaller tube, reaching down toward the mercury in the lower curve. On the side of the small tube is a capillary openingv, cut with a file, to permit a flow of gas when the opening at the end of the tube is closed by the rising mersury. The liquid used in the bulb is a solution of calcium chloride, and in the bend of the tube is mercury. Other liquids may be used. The incubator was used last spring in class work in bacter- iology and gave good satisfaction. The greatest variation in temperature observed was not over 2^ degrees, and this only when the room became quite cold. The usual variation was not over 1^ degrees. Experiment shows that the temperature in the incubator increases from the lowest shelf to the highest, if the burner is placed under the opening of the pipe, or near it; but if the burner is near the front of the incubator, or under the opening in the center, the temperature is nearly equable throughout. BURIED LOESS IN STORY COUNTY. BY S. W. BEYER. The lowan till is not known to be present in Story county. The trend of its southwestern margin which crosses Johnson, Iowa, Tama and Marshall into Hardin county, if maintained with reasonable constancy, would carry it safely beyond the confines of the county. The loess, the silty apron of the lowan, although suspected to be present on account of the geographic position of the area and of certain topographic contours which are decidedly loess-like in character, was not recognized cer- tainly until during the present field season. The loess is now known to appear at numerous points along the flanks of the deeper cuts in Indian Creek and Collins townships, in the 118 IOWA ACADEMY OF SCIENCES. southeastern corner of the county, near the limit of the Wis- consin drift, and there are occasional exposures in Franklin and Washington townships, along the tributaries of the Skunk river and Squaw creek, in the west central portion of the region. It is to the latter occurrence that it is desired to direct atten- tion. The best exposures may be viewed on sections 5 and 34, in Washington township, along Clear and Walnut creeks respec- tively. The Walnut creek section shows: feet. Drift, yellowish above, bluish below (Wisconsin) 20 Loess, sandy below 20 Clay, blue with much coarse gravel exposed The loess is silicious throughout and the upper four feet is distinctly joined and stained a faint yellow-brown along the joint planes. It grades downward into a massive, structureless, pale blue clayey silt which contains, in places, an abundance of root casts, wood fragments and black. Carbonaceous spots and emits a distinct swamp like odor. The entire deposit is highly calcareous and carries a rich gastropod fauna. Prof. B. Shimek identified the following forms, the majority of which are strictly terrestrial. Zonitokles shbnekli, (Pilsbry) P. & J. Spliyradmm edentulnm alt kola, (Ingersoll) P. &. J. Pupa muscoruiii, L. Bifidarki jjentodo)), (Say) Sterbi. Vertigo ovata, Say. Co'i 'ulus fu Ivus , (Mull). Polygyra multilineata, (Say) P. & J. Pyramidula striateUa, (Anth.) P. &. J. Vallonia costata, (Mull) Sterbi. Succinea lineata, Binn. Succinea avara, Say. Limna'a hroiulis, Say? Loess concretions are relatively scarce and are diminutive in size. The deposit shows no signs of oxidation or leaching where the drift covering is thick; but where the covering is so far reduced as to afford imperfect protection from the w^eathering agents, both leaching and oxidation may be noted, and here, alone, are lime concretions to be found. It is obvious that little or no alteration took place prior to the deposition of the overlying drift. IOWA ACADEMY OF SCIENCES. ng The outcrop along Onion creek is an almost exact dupli- cate of the Walnut creek section. The drift mantle is thinner, and from two to five feet of loess has been stained to a yellowish buff, and loess concretions are more in evidence, thus attesting to the greater progress made in leaching. Here, again, the upper portion is distinctly jointed, while lower the deposit is apparently structureless. Gasterpod shells abound throughout, but only two species, not listed previously, appear — Helicodiscus lineatus, (Say) Morse, and Pfanorbis bicarinatus, Say, both of which are terrestrial forms. In connection with these deposits of buried loess, certain arenaceous to silty gray-brown deposits, remarkably homogen- eous and devoid of pepples and bowlders, border some of the larger streams and are perhaps worthy of special mention. They are discussed here with the hope that they may throw some light on the process of loess accumulation. These highly- siliceous deposits flank the Skunk and the Squaw; are notice- ably present along the lower coarse of Indian creek, but are more in evidence along the eastern margin of the Skunk river valley, below Bloomington. The deposits attain a max- imum thickness of from three to five feet on the brow of the bluffs, thin rapidly inland and are scarcely recognizable more than a mile from the bluff scarp. These deposits are responsible for the heavy, sandy roads along so many of the streams in the Mississippi valley and are shunned alike by the teamster and the bicyclist. They are often known, locally, as "White Oak Soils," because that very well known and desir- able species of oak finds in them a congenial host. The deposits are thoroughly oxidized and leached and appear to be wholly devoid of structural or bedding planes. The coarsest materials which enter into their composition are found nearest the flood plain, and the size of the grain diminishes gradually as the deposit feathers out away from the river. The source of the materials and the transporting agent are not difficult to apprehend. The process of accumulation is going on to-day. The wind, sweeping across the broad flood plain, gathers up such material as can be transported and moves it toward the restraining bluffs. Perhaps only the very finest materials are given continuous passage for any considerable distance. But through successive short excursions, the coarser silt-particles 120 IOWA ACADEMY OF SCIENCES. and even tine sand-grains eventually reach the brow of the bluff and are deposited in the reverse order of their fineness*. The position of these deposits is determined, essentially by the surface contours. The wind, crossing the valley, impinging against the hills flanks, is deflected upward, and, coming in contact with the still air above, loses velocity, and, being unable to carry its load further, deposits it over the brow of the hill. In this location its position is reasonably secure, though the entire assemblage of deposits possesses the pro- clivities of the sand dune and may progress bodily inland. This process of wind transport and accumulation of materials may readily be witnessed. During early spring and late autumn, when large tracts of bottom land are unprotected by vegetation, dust storms are common and, often during a single " blow, " a measurable deposit is accumulated. If this be true now, how mucli greater must have been the efficiency of the winds, which blew across the mud flats, before vegeta- tion had time to reclaim the valleys, so recently vacated by the Wisconsin iceV The prevailing winds for central Iowa during spring and fall are from the west and hence the greater accumulation of SBolian deposits oq the eastern flanks of the streams. These deposits are worthy of more than passing notice, when viewed analytically, on account of their striking similar- ity, in many respects, to the loess. Structurally, texturally and in composition and distribution, there is a remarkable resemblance. Both are essentially devoid of stratification planes, possess a uniform, open texture, are highly siliceous, being composed chiefly of silt and fine sand, and appear to be genetically related to the chief watercourses, along which they attain their maximum development. True, the loess is usually highly calcareous, but this may readily be referred to a difference in the condition of the materials drawn upon, and «A most luminous and helpful discussion of wind erosion, transport and deposi- tion, will be found in Professor Udden's memoir, entitled " The Mechanical Composi- tion of Wind Deposit*," published by the Lutheran Aug-ustana Book Concern, of Rock Island, 111., 1898 The subjoined table gives the approximate maximum distances over which quartz fragments of different dimens ons may be lifted by moderately strong winds in single leaps. Gravel (diameter from 8-1 mm.) A. few feet. Coarse and medium sand (Diam. 1—1-4 mm.) Several rods. Fine sand (Uiam. 1-4-1-8 mm.) Less than a mile. Very line sand iDlam. 1-8-1-16 mm.) A few miles. Coarse dust (l-Ki— 1-32 mm.) 200 miles. Medium dust (l-;«-l-04 mm.) 1.000 miles. Fine dust (1-64 mm , and less) Around the globe. IOWA ACADEMY OF SCIENCES. 121 be wholly independent of the process of accumulation. It is now pretty generally conceded that the loess is genetically related to the lowan drift, — perhaps the over wash from that sheet. It is also well known that the lowan carried the largest and freshest bowlders of any sheet and it is reasonable to suppose that the liner materials were equally fresh at the time they were deposited. This is evidenced by the lowan drift itself, the surface, only, showing any signs of weathering. The mud flats were, doubtless, much more important then than now, and if atmospheric circulation was equally as vigor- ous as at the present time, wind erosion and deposition would be much more widespread and important, and the rate of accumulation might be so much accelerated that oxidation and leaching of the rock meal would be imperfect or almost wholly wanting. The loess deposits, which have been protected by the Wisconsin drift, lend credence to this view. The exposures near Kelly and Ames are not only unoxidized and unleached, but still retain their original blue color, which is so characteristic of unaltered secondary deposits. These deposits also emphasize the extremely short time interval between the deposition of the loess and the Wisconsin advance. The loess, whore unprotected, is a straw to gray-brown throughout, and the lime concretions sufficiently attest that incipient leaching has begun. In places where the deposit has neither lost by erosion nor gained by deposition, the leaching zone varies from two to four feet in thickness and is identical with the wind accumulations along the streams of to-day. The former, in all probability, originated through the rapid accumulation of perfectly fresh materials from the extensive mud flats and overwash plains, which formed an apron to the lowan till sheet, while the latter represents the much slower assembling of the leached and oxidized materials from the alluvial plains of to-day. While the processes which obtained during the two sets of deposits cannot be demonstrated to have been identical, their inherent resemblances and environments are certainly very striking. Aside from the comparisons already made, they are very closely related faunally. Professor Shimek" has shown, that with few unimportant exceptions, the loess molluscs were all air-breathers, wiiose habitat must have been very similar to that which prevails in the Iowa-Nebraska region of to-day. *The exhaustive memoirs which embody the results of this Iteen, conscientious observer and conservative wiiter may be found in the recent volumes of these pro- ceeding's. 122 IOWA ACADEMY OF SCIENCES. NEW LIGHT ON THE DRIFT IN SOUTH DAKOTA. BY J. E. TODD. Hitherto, the writer's study of the drift of South Dakota has led him to consider it to belong mainly, if not entirely, to the Wisconsin epoch. The reasons briefly stated are as fol- lows: (a) The numerous borings made in the state for artesian wells, have nowhere revealed distinctly, well defined forest- beds or soils, such as are found in some other regions. Though limited sheets of sand have been found in till at certain points, it has not been clearly proved that they are not such as might have been formed by sub-glacial streams or a slight advance of the ice-sheet during a single period of occupation. A few exposures described herein in the eastern part of the state have thrown some doubt upon this point. {b) The drift in northeastern Nebraska, though suggesting previous advance by an ice-sheet, is, nevertheless, from its thin- ness and its relation to the A Itamont moraine, thought to be due, in part, to the marginal waters; with a possible sub-glacial origin for a portion of it resulting from an extreme advance of the ice- sheet, slightly antedating that moraine. Because this conclusion seemed to disagree with those derived from other regions, the writer's results of several years' work in the Missouri valley have been withheld from publication for several years. This summer, while revising these results, the following inference presented itself. It is strange that it had not sug- gested itself before. I. Inference from the TroiigJt of the Missouri River. — ^Since 1884, it has been generally recognized that the relation of the outer moraine and its drainage channels and attendant deposits, to the Missouri river, and the narrowness of the channel of the latter above Yankton, with the reflection of pre -glacial topog- raphy in the ice movements, all indicate that the Missouri river was displaced from the James river valley, and forced to take IOWA ACADEMY OF SCIENCES. 123 its present course above Yankton, by the advent of the Wiscon- sin ice- sheet. Now the inference mentioned is this: that if the Missouri v^as so displaced by the Wisconsin advance (and this hypothesis certainly furnishes the best explanation of the known facts), then the James river valley was occupied by the stream previous to that time, at least during the so-called Kansan stage. (Possibly some of its upper tributaries may have discharged to the northeast in pre-glacial times.) If so, we can hardly conceive any sub-glacial till occurring in or west of the axis of that valley or in the Missouri valley above Sioux City. That the James river valley and that of the Missouri river below Yankton, are really identical is indicated by their widths and depths and relations to the drift. If this were not true, then we must believe that both the James valley and the wide Missouri valley below Yankton are of pre-glacial origin to their present depths; that the Missouri was displaced by the Kansan advance; that it must have had another channel below Niobrara or Yankton in that epoch, and that that channel has been so filled that it is unrecognizable, while the Missouri below the latter place has been kept unfilled in some inconceivable way during the recession of the Kansan ice and particularly during the deposition of the loess. If the latter be true, it adds another complication to the problem of the origin of the loess. If the James valley was not a pathway for ice during the Kansan stage, then, if the till in Kansas is really of the Kansan stage, the ice forming it advanced from the Des Moines valley, and the first excavation or the re-excavation of the trough of the lower Missouri is post-Kansan and post-loessial. This the writer urged in his Missouri report,* where he also pointed out an adequate cause for the subsequent great erosion, in the floods of water coming from the whole western margin of the retreating ice-sheet, as well as from the eastern slope of the Rocky Mountains; but he refrains from theorizing further till we have considered other recent observations. We shall find some difficulty with this view. II. Old Soil in the Big Sioux T«7fe;/. — Early in September last the writer, with Mr. Bain, of the Iowa Geological Sur- vey, and Mr. Leverett, of the U. S. Geological Survey, visited some instructive localities, near Sioux Falls, which had attracted the attention of the writer; first, in his examination of 'Missouri Geological Report, Vol. X. 124 IOWA ACADEMY OF SCIENCES. the region in 1H84, and later, during the season of 1897. Allu- sion is made to former observ^ations in Bulletin No. 1, of the South Dakota Geological Survey. In the grading of streets in Sioux Falls, at several points, a dark band resem- bling soil was noted. This is true more particularly north and west of the brewery. This band was first explained by the writer, as marking a temporary flood-plain of the Big Sioux during some stage of the occupation of the outer moraine He was unable to find evidence of its extending very far from the stream. The soil was underlain by till, and also overlain by that which seemed to be of nearly the same age. During the recent visit, not only were these localities re- examined, but others, developed by more recent grading, were observed near the postofiice, and a more notable example was found a mile or more northeast of the postofiice, in cuts along the Illinois Central railroad. At the latter point, there were found distinct traces of a buried pond, somewhat like a basin of the present. In its deeper portions, there is a de^jth of several feet of dark soil, containing numerous fresh- water shells — Valvata, Planorbis, Limnea, and also fragments of a cervical vertebra of a large vertebrate; fragments of turtle-shell, resembling the common mud-turtle in appearance and size, and two or three small bones, apparently of an animal about the size of a rabbit. The visit was brief, and further investigation would doubtless reveal more fossils. The vertebrate remains were submitted to Prof. William B. Scott, of Princeton, who determined the largest to be a cervi- cal vertebra of a horse. The other bones were undetermin- able. Through the thoughtfulness of Mr. Bain, a series of the shells was submitted to Professor Shimek, in time to have his determinations for this paper. His report is as follows: "The following are from the Illinois Central railroad cut east of Sioux Falls, S D. : 1. Planorbis bicnrinatus Say. 2. Phinorbis j)arvu-s Say. 3. Physa heterostropha (Say) Say. 4. Liiintea caperata Say. 5. Vidvafa triGarinato (Say) Say. •'6. Sp/Kcriuiii sulcation (Lam.) Prime. 7. Pisidiinii coiiipressnm Prime. 8. V((Uonia sta fa (Mnll.) Ster. Iowa Academy of Science. Buchaaan Gravels East of Sioux Falls. IOWA ACADEMY OF SCIENCES 125 "Of these, one to four are Puh inmates, five is a gill-bearer {Pro.sohranch), six and seven are bivalves, and eight is terres- trial. The set one to seven can be duplicated in most of our northwestern i3onds with muddy bottoms. Eight is terrestrial, but grows sometimes near the edges of ponds and is common along streams. There is one specimen of this. " The other lot from Sioux Falls, S. D., 'near the brewery, ' contains two species: '^ Liinnea caperata Say, di,nd Piano rb is albi/s MillL, probably. The specimens are poor. Both of these are common in north- western ponds to-day.'' West of this pond hole the rest of the underlying till had apparently had its soil, if ever formed, removed by the erosion attending the deposition of the overlying till. Between the two tills is a considerable deposit of gravel. The lower till was comparatively free from pebbles of any considerable size and has been referred to by the writer in his correspondence as a pebbleless clay, but more careful examination during the recent visit, brought out the fact that it contains small pebbles of crystalline rocks evidently of northern origin. In places it is distinctly weathered and resembles loess in color. In such cases, it failed to show effervescence when tested with acid. In the overlying gravel were numerous rotten pebbles and bowl- df rs. The overlying till revealed few, if any, rotted bowlders. This break between the lower till and the upper till which is so distinctly marked at some points in the vicinity of Sioux Falls seems quite even and horizontal. In the city, tests willi acid did not distinctly show difference in age between the upj^er and lower tills. In general, effervescence was prompt. East of Canton, there was a similar difference noted between the upper till, which was quite stony, and the lower compara- tively pebbleless till, which presented similar characteristics to those noted northeast of Sioux Falls. Between these tills was a deposit of fine sand and interstratified silt. Traces of this same horizon were traced east of Beloit, Iowa, and west of Fairview, S. D. In the latter locality, the lower till was not distinctly traced. It may be remembered that Mr. Bain, in his report on Woodbury county, Iowa, calls attention to the fine sand underneath the till at a high level northwest of Sioux City. At that point, no till had been found underneath the sand. It is known at one or two places to rest immediately upon Creta- ceous beds. In that sand, which is e.Kcavated extensively for 126 IOWA ACADEMY OF SCIENCES. use in Sioux City, there were found teeth, which were deter- mined by Professor Cope to be Equvs major. They would cor- respond in size, so far as can be judged, to the vertebra found near Sioux Falls, and it suggests in a striking way, that we may have here traces of the "Equus'' or "Sheridan beds" that have been observed extensively in western Nebraska and Kansas. It perhaps should be added that quite thick deposits of till with gravel occur at a lower level near the Missouri at Riverside park, and seem to be of recent date. III. Observations Near Gar ret son. — The same party also vis- ited Garretson, northeast of Sioux Falls, not far from Pali- sades, S. D. That locality is especially interesting because of a small semi driftless area adjacent. Along the railroad the cuts from Palisade to about two miles north of Garretson, failed to show anything like till, and loess was exposed several feet in depth resting upon the surface of red quartzite. This red quartzite is cut into ravines at least forty feet deep in places, but there is no trace of any mass of till, nor of strict on the surface of the quartzite. More careful examination showed that a few scattered pebbles and bowlders of northern origin were to be found in the crevices of the quartzite, but nothing that would demonstrate that the region had ever been mantled with a deposit of till such as occurs elsewhere. East of town within a few rods, the till appears and in gravel beds found in that direction numerous rotten granite pebbles were found indicating greater age than is common within the moraine. About a mile east, and further to the southeast and south, are conspicuous knolls, largely composed of drift gravel and sand, resembling osars. About a mile south of the town, one of these has been cut into and building sand has been taken from it for several years. It shows several feet of gravel and pebbles resting upon a mass of irregularly stratified sand. In a rail- road cut to the east of it, there is found the unusual appearance of a stratum of gravel and bowlders overlain with loess several feet in depth, and resting upon a loess-like silt which is also shown several feet in thickness in some places, while else- where it is replaced by loose sand. It could not be distinctly shown that the lower silt was of markedly older age than the upper. IV. Prec/lacial Deposits in Tiirkeii JUih/e. — In the examination of Turkey ridge, there was found, at a point about four miles south of Irene, Clay county, S. D., a stratum of loess like loam IOWA ACADEMY OF SCIENCES. 127 underlying- the drift, and resting, judging from an exposure of that several rods away, upon chalk deposits. A more careful examination may possibly reveal the characteristics of older till in these deposits, but no yjebbles were noted where it was studied. Reports from wells in the region seem to corroborate the idea of a preglacial silt in that locality. Turkey ridge is a high divide between the Vermillion and James rivers, which became an interlobular portion of the Altamont moraine. V. Recent Fossil. s from Near BracUey, Clark Coiotty, S. D. — In 1895 Miss Helen M. Buzzell, a teacher in the common schools, became interested in some curious things found in digging wells a few miles north of Bradley. I have not been able to visit the locality and can only quote from her description: " The land here is very rough, showing hills, little level places and big sloughs, or old lake beds The well is about fifty rods from the foot of a hill, which, I should think, is nearly 300 feet high, at the head of a slough. The latter is hardly a ravine — rather a hollow — and here are the figures as given by the man w^ho dug the well, describing the different soils as they came: FEET. 1. Black loam 3 2. Crumbly .\ellow cla* 14 3. White material 3 4. Tree 9 5. Blue clay 6 "This is on Mr. J. D. Foley's place, section thirty-five. Spring Valley township, six miles from Bradley; there are others similar. " The white material is evidently a white marl. It contains VaJvata fricarinafa, Phntorbis bic((rinati(s, P. parvus and Llriinea huiiiiJis. Miss Buzzell sent numerous pieces of wood, most of which I judged to be coniferous. They show the characteristic tracheids and resemble tamarack. Specimens of muck. No. 4, contain fresh water shells similar to those in No. 3, and also Anadonta and Spcerium bulcatuni. The data are not sufficient as it would seem for asserting that this deposit is inter- glacial. It may result from the filling of a recent lake basin. If such is the case, it resembles the locality north of Grand View, in Douglas county, which was described in Bulletin No. 1, of the South Dakota Survey, page, 126. Both localities are inside the Altamont moraine. 128 IOWA ACADEMY OF SCIENCES. (kmduslons and Sufj{/e:>itio)i.s. — Prom the data given, we seem justified in concluding that there had been considerable deposi- tion of till over the region of the Big Sioux valley, previous to the occupation of the Altamont moraine of the Wisconsin epoch. The readiest explanation, no doubt, is that the ice sheet spread, at least, over the region mentioned, although it seems not impossible that the comparatively pebbleless till which has been observed at Sioux Falls and east of Canton, may have been deposited by marginal waters, and while occasional bowlders are found they are by no means as numer- ous nor as large as in the Wisconsin till. From the compara- tively drif Lless region ab )ut Garretson and the direction of the striae west of Palisades, we can scarcely doubt that the valley of the Big Sioux was occupied by a lobe of ice but that there were patches east which were comparatively stationary. We have not given the subject sufficient study to speak with confidence and yet it seems permissible, at least, to offer a few suggestions which are little more than speculations. If we examine the map of tlie region, we shall find that the valley of the James river in South Dakota is separated by a high table land rising over considerable of its surface, to a height of 2,000 feet above the sea. Immediately north of the SoLith Dakota line, the James river makes its nearest approach to the Ked River of the North, the distance being about seventy miles. At that point the divide between the streams is very low and close to the former stream. A cut of twenty to twenty- five feet would probably turn the James river into the Wild Rice and Red rivers. From that jDoint northward, although the divide is about 150 feet above the James, there is no we 1 defined ridge, as further south. This brit gs us to a serious objection to the view that the course of the Missouri was down the James river valley, especially while the mass of ice was moving up the Red river valley. Moreover, some have thought that the ancient drainage was once northeast through the valley of the Wild Rice. If such were the case, the difficulties of keeping the James river valley open for pa.ssage of the water while the Red river valley was occupied by ice, would be still more difficult to explain, if not inconceivable. It seems, therefore, more probable that the dividing ridge, which is now so well defined in South Dakota, previous to the W^isconsin epoch, extended further north, possibly as far north as Devil's Lake; though it was narrower and probably lower there than IOWA ACADEMY OP SCIENCES 129 farther south; and that this ridge played an important part in hindering the advance of the ice until it had accumulated sufficiently to break through into the James river valley, as it did during the Wisconsin epoch. This would be the more easily explained if the ice sheet from the north, i. e., from the Keewatin center was not so vigorous in the earlj^- stages, i. e., in the Kansan and pre-Kansan stages. From a general consideration of the extent of the so-called Kansan till as compared with the Wisconsin, we may infer that the natural center during the former stage was further east; probably, northeast of Lake Superior. In fact; we may con- ceive that some of the higher points north of Lake Huron were the first to receive a permanent ice cap. As the region became more chilled, the zone of accumulation would extend naturally along the more elevated surface of the ice and then the great- est accumulation would lie naturally near the edge of the zone and advance slowly outward. In this way, we may perhaps account for the greater vigor of the streams passing down Lake Michigan and Lake Superior during the Kansan stage or, as some would say, the latter during the Kansan stage and the former during the Illinoian stage. If we believe the ice to have here pushed forward southwest in the axis of Lake Superior basin, it is not difficult to conceive that its course would lie diagonally across the state of Minnesota, being con- fined in a broad shallow channel between the highlands about Itasca and the region of central Wisconsin, that it was directed to the Minnesota valley and across it against the high transverse ridge of the ''East Coteau" the high divide separating the Minnesota from the James, which now has an elevation of 1,700 to !2,000 feet. From the shape of the land and the course of the stream, it seems not unlikely that the highest elevations were along the axis of this stream. As the Des Moines valley to the south offered an easier slope, we may conceive the ice sheet to have expanded more rapidly in that direction and to have spread out during the Kansan stage, from that valley westward and south into northwestern Missouri. We may account for its failure to press westward over into the James valley by the elevation of the Coteau region and by the divert- ing influence of the Big Sioux valley, which we may suppose had greater effect upon the thinner edge of the ice which there lay in the zone of ablation. The failure of the ice to press equally northward may be 130 IOWA ACADEMY OF SCIENCES. accounted for, not only by the ridge, as we have before stated, but by the depth of the Red river valley together with the delaying influence of a north slope. For we conceive it reasonable to suppose that the ice would be more plastic in the region of greater warmth and that there would be more rapid accumulation along the southern side of the zone of accumulation. Both relations would favor such a conclusion.* If such a state of affairs is conceivable, we may not only account for the Kansan till, so far as it is sub-glacial, but we may have found a partial explanation of the more difficult phenomena of the course of the ice during the lowan stage. One of the strange things connected with that stage is the persistent course of the ice toward the southeast. Now, if the summit of the ice lobe, during the Kansan stage, rose to the altitude of the zone of accumulation in western Minnesota, we may conceive that it might for a time act as a secondary center of glacial motion. The persistent easterly tendency of the ice might be partially accounted for in this way, but we may find another factor in the possible subsistence of the driftless area. The very existence of that area has suggested its former greater elevation, and we have learned to expect subsidence as one of the effects of ice occupation. The Kansan load, acting for a time on the west, and subsequently, if not in part contemporaneously, the Illinoian on the east and south may have at last brought it down to a considerable lower level. The movement of the lowan ice lobes, both in Iowa and Illinois, would harmonize with such a view. See Leverett's map, " Interglacial Deposits in Iowa, " page 8. * Moreover, Mr. Upham's study of Lake Agasslz would lead us to think there was then greater northward elevation. IOWA ACADEMY OF SCIENCES. 131 SOME PHYSICAL ASPECTS OF GENERAL GEOLOG- ICAL CORRELATION, BY CHARLES R. KEYES. CONTENTS. T ^ ^ * PAGE. Introductory 131 Nature of the problem of geologic correlation 133 Foundation of geological chronology 134 Methods of correlation 136 General statement ; . . 136 Chief methods at present in use I37 Inadequacy of existing methods 139 Extension of the usual criteria to general application 140 Main considerations 140 Biological relationships 140 Unconformity I44 Community of genesis 146 Historical similarity 147 Physiographic development 148 Correlation of provinces of dissimilar geological history 149 Conclusions 152 INTRODUCTORY. The main object of the present communication is to form- ulate, brieily, certain results which have been obtained in the course of recent attempts to parallel some of the geological terranes in the Mississippi valley. The suggestions they offer appear to have a much more than local bearing, and to affect the stratigraphy of the entire region. They also have an important influence upon the whole problem of general correlation and, perhaps, also, even upon our present system of geological classification. In the whole domain of natural science, there is perhaps nothing that is more striking, through all stages of its consid- eration, from beginning to end, than the fact that natural phenomena are rarely the outcome of the action of single, simple laws. They all originate in so many remote and complex processes that those which are really primary and essential in character, are often largely or completely obscured by those which, though most conspicuous perhaps, are altogether 132 IOWA ACADEMY OF SCIENCES. secondary, or even accidentally associated. That this is true in every department of science is clearly shown, not only by its history, but particularly by the classifications of the phenomena that have been followed during the different stages of its development. In the progress of every branch of knowledge, one of the first considerations to receive attention is a systematization of the known facts. This orderly arrangement is one of the earliest prerequisites demanded of the branch in its attainment to recognition; while its advancement is measured by the degree of tBuXonomic completeness and the critical criteria adopted. The bringing together of the various phenomena, so that some sort of systematic relationship is made to exist among them all, is the initial step in raising the particular department of knowl- edge to the dignity of a science. As progress is made, a gradual evolution takes place in the fundamental grouping of the facts. In the beginning, a classification, rude though it may be, is fashioned according to the superficial features, which are most striking at first glance. It is, at a later stage, modified to one in which similarity of characters, irrespective of natural relations, is taken into account. A vastly more advanced conception is classification based upon affinity, in which, for similarity of features, there is substituted similarity of plan. The final stage is the causal, in which origin and the processes become the dominant and determining factors. In the expansion of the multifaceted science of geology, the classification of the phenomena presented has been no excep- tion to the rule. In the department of stratigraphy, that part of the general subject which has to do with the history of the changes which have taken place in the lithosphere, that j)art in which we find a measure of geological time, and in which we determine the sequence of geological events, there has been the same growth as in the other branches of the science. As in those other branches various standards of comparison have given away, one after another, to new standards more in accord with the general advancement of human knowledge, so also in stratigraphy has there been a passage from one criterion to another. In the successive replacements, however, of one set of criteria by another, the abandoned ones have not always been found to be altogether wrong; and they usually continue to exert a more or less profound influence long after they are thought to be forgotten. These various classifications, based IOWA ACADEMY OF SCIENCES. 133 first upon some one particular phase or striking feature, and then on another, are not entirely erroneous, for the reason that they represent some special workings of funda- mental laws that are not, and cannot be, always discerned, until greater advancement in general knowledge has been made. In this respect, they partake of the nature of working hypotheses. A long time may be required to prove their faults, and then new schemes arise. In practice, then, the establish- ment of a rational system of geological chronology, or classi- fication, is not to be sought in the comparison of any one set of external features, but rather in the direct causes or processes which have given rise to the phenomena. The final outcome is reached by a comparison of all the groups of data relating to the physical history as a whole. NATURE OF THE PROBLEM OF GEOLOGICAL CORRELATION. Regarding as the main function of geological correlation, the establishment of a practical scale of stratigraphic succes- sion, to which may be referred all geological terranes, the critical critera adopted become essentially the basis of geolog- ical classification or of historical geology. Moreover, a rational classification of geological phenomena reflects the genesis of the events recorded, and this is manifestly the ultimate aim of all methods of paralleling strata. It is a favorite simile of geologists to liken the progress of geological events to human history. But they stop short of the most important step of all in not making the comparison full and symmetrical. In the history of mankind, there is in the time units, the year, the decade and the century, an abso- lute scale for gauging all events. In developing geological history, this standard of comparison, of course, fails, because of the inapplicability of our ordinary units of time, and with this failure, no attempt is made to carry out the all-important idea that is fundamental in human history, and look for some other unit that is, in its nature not comparative, not variable, not local in application, but fixed and independent of any inherent character. As human history is traced backward, the clear coloration of the present gradually fades with time, until lost in the haze of distance and uncertainty, tradition and myth. That the growth and progress of the races of mankind have been much the same in all the various parts of the world, is generally 134 IOWA ACADEMY OF SCIENCES. admitted, but in each part the details, and perhaps some of the characteristic larger features, are very different. The whole history is made up of the histories of the parts, of the nations, of the provinces. In a similar way, geological history reaches back into a haze of distance, compared with which the beginnings of human history are but as a moment ago. As the history of man is a history of nations and dynasties, more or less intricately related, so also is geological history a history of parts, of provinces, overlapped, interwoven, merged into one another, but each retaining, more or less distinctly, its identity, thrusting out its idiosyncrasies, and presenting the evidence of its relations with its neighbors. The development of geological provinces has another parallel in the progress of nations. Some great events have been recorded in the history of all; others in only a few. At certain periods a mingling, an absorption, or a complete effacement of some parts has taken place; at other times has occurred conquest and expansion. Could the events of all nations that have ever existed be arranged on a chart, or in tabular form, so that those concern- ing each could be brought together in a vertical column, and so that the different columns would stand side by side in their proper positions in the time scale, with its major sub- divisions marked off by horizontal lines, it would be found that at certain times great events would affect several and perhaps many nations, and that at such times similar events would affect different groups of nations, or part of one group and part of another. In the same manner are the events of geology recorded in different parts of the earth. While the general sequence is similar everywhere perhaps, great changes affect the different parts in different ways and with varying intensity. So, in tab ulating the geological events of different provinces, the standard corresponding to the time scale in human history must be absolute and far-reaching, and not changeable and local. The determination of such a standard is the one great problem of stratigraphy. THE FOUNDATION OF GEOLOGIC CORRELATION. In the correlation or comparison of geological terranes, experience has shown that the subject may be viewed from at least four very different points of vantage. The aspect IOWA ACADEMY OF SCIENCES. 135 presented may be: (1) Local, (2) provincial, (3) regional and (4) general. The last should be clearly distinguished from the others. With the various methods which have been followed from time to time in correlative inquiry, the almost universal practice has been to attempt to base the broader generaliza- tions upon criteria that are, in reality, applicable only to limited areas. Hence, in passing from the more local to the more general, difficulties have always arisen which have become more and more formidable in direct proportion to the extension of the local scheme. Most of the methods that have been applied, and that have been found to answer locally, have fai ed when extended over larger districts. The real problem, then is to find some means of solving the difficulties of the latter, or more general. In the attempts to do this, or when broadly applied, most of the correlation criteria have proved very inadequate. A little consideration will make the reasons evident. As the specific distinctions that are regarded as decisive in a given locality are extended more and more widely, they change and all are gradually replaced by others which may be very different. The physical conditions that have given rise to the various distinctive features, or the processes involved in their production, themselves change from place to place and from time to time. In seeking for a suitable means of carrying on correlation it is manifest, at the outset, that in no case should the critical criteria deal with the intrinsic features as such, but with the causes producing them. Moreover, the great factor to be taken into account in every standard of comparison which has to do with the correlation of strata, is a definite or absolute basis to which the various minor, or local and provincial, successions can be referred. This fundamental conception grows out of a consid- eration of the nature of sedimentation itself. The features which have in the past had the greatest weight in geological correlation, have been those which, in reality, are partly or entirely unrelated to the deposition of strata. In attempting to seek a criterion that is fundamental in strati- graphy, it is pertinent at the start to inquire into the real nature of sedimentation, into the causes producing it, modify- ing it and limiting it, into the forces called into action, in sub sequently obliterating their results, in fact, into all of the primary processes involved, and into the secondary processes which tend to obscure the actual workings of the real and 136 IOWA ACADEMY OF SCIENCES. fundamental laws. Only in this way can the main object, the establishment of an adequate and elastic system of geological correlation, be attained, and a ready interpretation of the his- tory of terrestrial phenomena be made. Since, from the strata of the globe must be deciphered the records of its history, the leading facts to be ever borne in mind and to be recognized to their fullest possible extent, are that the elements of sedimentation are in large part the products of land decay, which form seaward-creeping fringes around the continental masses, and that the cessation of the action of the processes favorable is one of the prime factors in beginning each new cycle, or great epoch, in the physical history. SOME METHODS OF GEOLOGICAL CORRELATION. General Statement. — In the present connection it is unneces- sary to enter into details regarding all of the various stand- ards of correlation that have been proposed. As all systematic arrangements of sedimentary deposits have for an ultimate end the real determination of the superposition or relative succession of all strata, it is manifest, from what has already been said, that the scheme incorporating in its plan the actual sequence of the processes that have produced the events, is the one which most nearly meets the requirements of a rational foundation for geological chronology. In propor- tion, therefore, as a classification is genetic, it is of value as epitomizing the history of a region. From the time when the real significance of the bedded character of nearly every portion of the lithosphere open to observation first came to be recognized, at the beginning of the eighteenth century, the normal order of suj)erposition and the equivalency of the layers has formed one of the chief problems of stratigraphy. In a single rock exposure it is, ordinarily, easy to determine which beds were laid down first and which last. However, in making a comparison of two sec- tions which are not visibly connected, the case is not so simple; and when the two sections are widely separated, the difficulty of paralleling them is correspondingly increased, and exact correlation, perhaps, finally becomes entirely out of the question. It is the special province of geological correla- tion to establish a general chronological sequence of all rock successions, particularly those more or less widely separated. In the past, the standards for this determination have been TOWA ACADEMY OF SCIENCES. 137 numerous. As they come to be tested practically in the field they have been, one by one, abandoned entirely, passed over, or, in lieu of something better, have been used only provision- ally, or with reservation. No single criterion has yet been proposed that answers the purpose successfully. Although some one of the various methods is commonly used as the principal one, others are almost invariably also taken into account at the same time. Hence, it is universally recognized that few correlation problems can be now settled by a single standard alone. Chief Methods. — In geological correlation the most important of the criteria that have been most generally employed may all be assigned to two main groups, the biological or biotic, and the physical. At one time or another, each one of the sub- ordinate methods of both groups has been made all-decisive. At the present time all of these are used to some extent, either directly or indirectly. These minor methods have been recently arranged by Gilbert* in the following manner: I. Physical, through, 1. Visible continuity. 2. Lithological similarity. 3. Similarity of lithological sequence. 4. Unconformities. 5. Simultaneous relations of diverse deposits to some physical event. 6. Comparison of changes deposits have experienced from the action of geological processes supposed to be continuous. //. Biotic, through, 7. Relative abundance of identical species. 8. Relative abundance of allied or representative species. 9. Comparisons of faunas with present life. 10. Relations of faunas to climatic episodes. With possibly one exception all the methods of correlation which are included in these two catagories are strictly local in their scope, though it is the custom to regard them as applying widely, if not universally. For many years general correla- tions have been carried on almost entirely by the biotic methods. At the present time they predominate over all others. *Oong. geol. international, Compte Rendu, 5me Sess., 1891, pp. 151-155, 1893. 138 IOWA ACADEMY OF SCIENCES. and are, really, the foimdation of our commonly accepted sys- tem of geological synchrony. However, it is beginning to be recognized more and more clearly that organic remains are not the all-deciding factors in questions of correlation, that they are, in fact, merely accidental characters, and that when depended upon they must always be taken in connection with physical features. In actual practice they are regarded as corroborative evidence after the main points of the special problem under consideration have been determined by other means. In the recognition of these difticulties it was recently stated" that all the principal characters, stratigraphical, lithological and faunal, of every formation, were so intimately interrelated in origin that the proper interpretation of any one of the three classes of phenomena presented should, under normal condi- tions, indicate the more salient features of the other two, but that, ordinarily, great difticulties were encountered in attempting to infer the entire geological history of a series of beds from a single group of facts. It was fully appreciated that the geological records were very imperfect, but at the same time they were not believed to be nearly so fragmentary as generally supposed, though the larger part was, in a great measure, more or less inaccessible; those portions of the lithosphere that were open to investigation were as yet only partially considered. For a long time to come, the territory open to inspection would require constant study before the history could be made even measurably complete. Never- theless, at the present time, it was considered absolutely necessary to carry on investigations, involving the historical sequence of geological eveuts, along all three lines at once, every fact being needed to throw light upon the general scheme. If the problems were attacked in any one of the three directions alone, without due regard for the evidence presented by the others, very different, and perhaps antagonistic, conclusions might be reached, at least in the present state of knowledge. In the interpretation, then, of the geological history of a region, and in the erection of a classification of the formations in accordance with that interpretation, it is of prime importance to w^igh carefully all the evidence set forth by the arrangement, composition and contained organic remains of the rock series as a whole, and of its several parts regarded as distinct units. *Iowd, Geol. Surv., Vol II, p. 62, 1893. IOWA ACADEMY OF SCIENCES. 139 Inadequacjf of Existing Methods. — It has already been intimated that the basis of geological classification has been, at various times, in accordance with very different standards, and that these have continually changed. In passing from one to another, however, the change has been gradual and not abrupt. Being bound so inseparably to the past, it is well-nigh impos- sible for us to at once cast aside old ideas, even after w^e are fully convinced of their untrustworthiness. So, in clothing new conceptions in words, we unconsciously and unavoidably incorporate statements that are not only deceptive, but which have their foundation in error. Still, the expression of the new must be largely in terms of the old. In the dis- cussion of our standards of comparison, the old interpretations are naturally, yet unavoidably rendered, and more or less misunderstanding necessarily arises at first in the consider- ation of any new criterion. That every standard yet suggested for the determination of geological chronology has beeen inadequate, when taken singly, is conclusively shown by the practical tests that are being continually made. A satisfactory solution to the problem does not appear to be offered by any system yet proposed. It has almost come to be the despair of investigators. A few years ago, Whitney and Wads worth* gave up all hope of unraveling pre- Cambrian geology without the use of fossils. Walcott, f after reviewing the methods of correlation in his correlation essay on the Cambrian, concludes that "For the determination of synchrony, except in a limited area, there is little hope for satisfactory conclusions by any method yet devised. '' Gilbertt states that at present "the legitimate use of physi- cal methods of correlation will necessarily be local * «■ * The value of a biotic group for purposes of correlation depends (1) on the range of its species in time and space, and (2) on the extent to which its representatives are preserved. " Hughes, § in presenting the report of the British subcom- mittee on geological classification, clearly recognizes the fact that no one criterion is sufficient. "We must adopt the his- torical method * * * In geological history we must class together those results which naturally hang together, which *BuU. Mus. Comp. Zool., vol. VII, p. 563, 1884. +U. S. Geo]. Sur., Bull. 81, p. 43:h, 1891. $Cong-. geol. international, Compte Rendu, 5me Sess., 1891, p. 153. 1893. gCong. geol. international, Compte Rendu, 4me Sess., 1888, App. B., p. 9, 1891. 140 IOWA ACADEMY OF SCIENCES. belong, more or less, to one set of conditions as shown by the similarity of the inhabitants, as well as of the country occupied, and of the structures which remain; that is of the fossils, the stratigraphy and petrology of the district. Our greater divi- sions must be based on the more complete changes and the smaller upon the minor fluctuations which will be indicated only by the more sensitive and specially adapted forms of life, or by the more minute structural changes. " EXTENSION OF THE USUAL CRITERIA TO GENERAL APPLICA- TION. Main Considerations. — Among the various methods of parallel- ing strata, and in the broader phases of their consideration, there are certain points in several of them to which attention should be directed. The methods referred to are those which have, of late, received the greatest consideration. They may be included under the titles of (1) biological relationships, (2) unconformity, (3) community of genesis, (4) historical similar- ity, and (5) physiographic development. Biol 0(1 ical Uelationships. — As the various standards that have been usually used in geological correlation have been finally found to be useful only in limited areas, instead of being world- wide, or even of continental application, so also the latest one, which has so long held prestige, has been found at last to have no longer the unerring certainty in exact correlation that was once claimed for it, and in this respect to be no longer keeping pace with the advance of geological science. Like the other methods or schemes, it too is having its usefulness restricted to limited districts, and to be relegated to the subordinate posi- tion of a local criterion. Its accuracy remained unquestioned in the absence of more reliable criteria with which to check its results. With, however, the advent of more refined methods of working, its unreliability in exact general correlation has become very manifest. As a striking example, stands the eastern sea-board of the United States. Of it, McGee says that "nearly as much information concerning the geological history of the Atlantic slope, has been obtained from the topographic configuration of the region within two years as was gathered from the sediments of the coastal plain and their contained fossils in two generations. " It has come to be widely recognized that there are no more grounds for the claim that the succession of organic forms and faunas is an expression of the geological course of events and IOWA ACADEMY OF SCIENCES. 141 that it is the same the world over, than are the claims of the old Wernerian ideas of general sequence, based upon litholog- ical similarity. The element of error is identical in both. It is an assumed premise. Both the lithological and faunal characters must be regarded as largely accidental attributes of strata, and therefore cannot have the impeccable classif acatory values once ascribed to them. The formulation of the weakness of fossil criteria in general correlation may be passed over here. They are fully noted in the conclusions of Huxley,. Irving, Van Hise, McGee, Walcott, Brooks and others. The very basis of the method is highly variable, in the same way as that of lithological character. The preeminent position which paleontology has long held in geology, has been in great part due to its biological rela- tions, or environment. It has formed one of two chief lines of inquiry into one of the most important and most absorbing philosophical questions of the century. So overpowering has been its influence in stratigraphy, that it even has been urged that there can be no scheme of geological chronology which is not based upon it. As a science, paleontology had its rise in geology, though it is really a department of biology, and the vast expansion that it has undergone still closer welds it to the latter science. The whole tendency of its development, of late years, has been towards the biological side. Its use, in strictly geological work, has become more and more restricted and overshadowed by the physical sciences which offer a broader foundation. Without the slightest disparagement to its good offices in the past, it may be said that it can never have the exalted place in geology that it once had, though it will ever be of use in practical local stratigraphy, especially when taken in connection with other data Another reason why paleontology long had such an unpre- cedented influence upon geology is that it was so thoroughly permeated with pre Darwinian ideas of repeated creations and of sudden extinction of species and faunas. Hence no cor- relations, either local or over broad areas, have ever been precise, apparently, nor, in the absence of facts to the contrary, has the equivalencies of strata widely separated geographically been determined so positively, as those made out a generation or two ago. Even to-day geological correlations rest practi- cally unchanged on these manifestly insecure foundations. Since the beginning of the present century, when William 142 IOWA ACADEMY OF SCIENCES. Smith* explained a method whereby the different strata could be recognized by the fossils which they contained, organic remains have been the foundation of all geological classifica- tions. Of late years, when other methods have been devised, numerous discrepancies have arisen between the conclusions to be deduced from two sets of facts, and the question has begun to arise on all sides as to just how far the fossils can be relied upon in the correlation of geological formations. Huxley, t recognizing the fact that exact synchrony could not be established by means of fossils, projjosed the term, homotaxis, indicating similarity and not time-equivalency of organic con- tents. Irving, J and later Van Hise,§ and others, working in very ancient, non-fossiliferous rocks were obliged to swing loose altogether from the use of organic remains. McGee, || in discussing the subject, concludes that, in correlating by means of fossils, ' it is the weakness of the method that many rocks are too poor in fossils to be correlated thereby; that formations may be homotaxial yet not contemporaneous, and vice verm\ that fossil facies represent the product of two prin- cipal factors, of which one (environment) is so varia'^>le under local conditions, that the product is inconstant among the minor rock divisions, and that the geologic chronometers afforded by fossil plants, fossil invertebrates, and fossil vertebrates, respectively, give unlike time units and, some- times discordant readings. Today the larger groups are contidently correlated by paleontology; but leading American geologists no longer accept identity of fossil facies as final proof of equivalence among the minor rock divisions." In his correlation essay on the ' ' Cambrian of North Amer- ica, " Walcott*! not only says, as already stated, that "for the determination of synchrony, except in a limited area, there is little hope for satisfactory conclusions by any methods yet devised," but in referring to paleontology in particular, remarks that "all paleontologic reasoning is based upon known data. By the discovery of a new grouping of fossils, or a different range of known species, the identification of horizons may be materially modified. " As coming from the *Geol. Table British Org. Foss., 1815. ■t-Quart. Jour. Geol. Sic. London, Vol. XVII 1, p. 14, 1862. *U. S. Geol. Sur., 7th Ann. Rept., pp. 365-451, 1888. §U. S. Geol. Sur., Bull. 86, pp. 511-534. 1892. II Am. Jour. Sci., (3). Vol. XL, p. 36, 1890. "U. S. Geol. Surv., Bull. 81, p. 423, 1891. IOWA ACADEMY OF SCIENCES. 143 chief of American paleontologists, the recent utterances of H. S. Williams* are full of meaning : ' ' And now the modern school of paleontologists are demonstrating the fact that the divisional lines of the biologic or time scale do not correspond to those of the stratigraphic scale, but are determined by independent factors." So diverse are the divisions suggested by the fossils in the time scale from those indicated by the stratigraphy in the formation scale, that the same author saw the necessity of a dual nomenclature;! of a distinct set of names for the members of the two scales. In this connection, also there may be mentioned a discussion on the character of fossil evidence, by Brooks|;. It is espe- cially noteworthy as coming from a biologist, and is from a standpoint that is not and cannot well be considered by the average paleontologist. Although it is not mentioned in the discussion, it may be inferred that the proof is con- clusive that the fossils do not indicate the great antiquity of life that they are generally thought to, as deduced from the chief argument: that at the time of the earliest Cambrian forms life was already fully nine-tenths differentiated. It is shown that differentiation of life goes on with great rapidity along the shore, and more or less independently in different localities, on account of the fierce struggle for existence. The suggestive - ness of the statement is startling; at a single stroke it prac- tically deprives the fossils of the greater part of their value as trustworthy elements for general correlation, and relegates the whole method to the same rank as correlation by lithology, or similar succession The recent trend of paleontological progress has been rapidly in the direction of biology, rather than towards geology, but the effect of Brooks' suggestion is to remove it almost entirely from the latter field and to transfer it to the former. As in the case of certain of the other criteria of geological correlation, the usage of fossils becomes largely local. The weakest point of all in general correlation by means of fossils is the great complexity of the problem surrounding dis- tribution of organisms in space. The intricacy of the laws governing the geographic range of animals and plants, at the present time, is only understood in the most general way and *U. S. Geol. Sur., BuU. 80, p. 267, 1891. +Journal Geology, Vol. II, pp. 145-160, 1894. Uournal Geolog-y, Vol. II, pp, 455-479, 1894. 14 1 IOWA ACADEMY OF SCIENCES. scarcely yet capable of unraveling. How infinitely greater are the difficulties when not only space is to be considered but dis- tribution in time as well, and ail with material that at best is but fragmentary. No biologist would have attempted it. Uxconfontiify. — In its widest sense an unconformity is any discordance in sedimentation in which younger beds reposing upon older rocks give evidence of no direct connection, of interrupted deposition, or of a change in the prevailing physi- cal conditions whereby nonparallelism is developed in the stratification planes of the two formations. The phenomenon carries with it the idea of more or less pronounced warping of the older strata before the younger are laid down. In a some- what narrower sense, and in the one that it is perhaps most generally used, unconformity implies a tilting of the strata, their elevation above sea-level, and subjection to more or less pro- found erosion before being covered by the younger sediments. The irregularity in the juncture between two uncomformable formations is, in the majority of cases, a well defined line denoting a break in the continuity of conditions. In Europe, where modern stratigraphical science originated, the time-gaps indicated by unconformities have been regarded chiefly from a biological rather than a physical standpoint. The full sig- nificance of the interruption in sedimentation has not been appreciated so much in its bearing upon the conditions which could have given rise to such effects, as in its production of a well-marked hiatus in the faunal successions, or rather, by the introduction of entirely new faunas, perhaps, in the younger beds above. In the European countries also, the abrupt faunal breaks have been at the foundation of the separation of geo- logical history into its grander divisions, and of the strata into systems. In America the attempt to transfer the classification of Europe has not proved so successful, and the application of the same principles does not find the great gaps in the same places. The inferences are obvious. As a purely physical feature, application of unconformity to anything smaller than the great systems, has usually been sub- ordinated to the faunal or lithological criteria. It has been done, however, in a few cases with success; though not in such a way as to attract very much attention. Although marked physical breaks in the continuity of sedi- mentation have, from time to time, received some a'.tention in IOWA ACADEMY OF SCIENCES. 145 problems of correlation, it remained for Irving* to point out its great value in the classification of the nonfossiliferous, pre- Cambrian rocks of the Lake Superior region. The practical use of this criterion in stratigraphy was also later invoked in the consideration of the Carboniferous of the Mississippi valley f The special stress laid by Irving on the value of unconformi- ties as a basis for geological classification, has a wide bearing. In the application of the principle to the region that was Tinder consideration, it was shown that unconformities were the most important of all criteria in resolving into its grander subdivisions, a vast sequence of crystalline rocks, which, as in the case of other similar masses, had defied all attempts of sat- isfactory arrangement and correlation. Had Irving not been so untimely called from his field of labor, he might have possi- bly expanded his theme so that it would be of much wider, if not of universal application. It is not that he was the first to suggest the use of unconformities in delimiting the grander geological formations, for this, at the present time, is essenti- ally the real foundation of our accepted geological classifica- tion. Other criteria, however, have so overshadowed this one, that the fact of its ever having assumed an important role is well-nigh lost sight of, and consequently the physical breaks in stratigraphical succession excite little attention, except as interpreted by fossils. Their true significance is now very nearly, if not completely, overlooked. In the absence of fossils, Irving was actually driven to the use of purely physical methods in dealing with the metamor- phosed rocks. All attempts to arrange the latter systemat- ically, except upon faunal grounds, had been given up as use- less. In other regions, many writers before him had con- sidered the phenomenon of marked discordant sedimentation as a structural feature, and had actually gone so far as to regard unconformities as not only of regional, but even of intercontinental, extent. On the other hand, there were a very large number who believed that unconformities, at best, were only local phenomena and, therefore, of small importance in stratigraphy. It was Irving's particular mission to determine how far unconformities could be relied upon, in a limited district, to point out clearly that in some cases they *U. S. Geol. Sur., Seventh Ann. Rep., pp. 437-439. 1888. +BuU. Geol. Soc. American, Vol. Ill, pp. 283-300, 1892; and Iowa Geol. Sur., Vol. II, p. 10 146 IOWA ACADEMY OF SCIENCES. were of very wide, and in other cases of very limited extent, and, in the geological classification of the non-fossiliferous rocks of a whole province, to propose a plan in which uncon- formities occupied a prominent place Short though the period has been, since Irving 's time, there has sprung into existence a new department of geological inquiry, that not only reads later geological history in the geographical forms presented, but gives an entirely new insight into the real significance of uncomformable relations between the older rock masses. The bringing in of the geographic aids, to unravel stratigraphy, finds a hearty support and a wide expression. It is in the extension of Irving "s theme, as out- lined under the guidance of modern geographic interpretation, that stratigraphy is believed to have found a rational and practical method of correlation and classification that, in its fundamental concepts, is entirely independent of the usual and almost universal paleontologic standard. The specific appli- cations are referred to in another place. ('o)itjiitmlty of Geneais. — Correlation by community of genesis is a "simple application of the well known principles (1), that geologic processes may be inferred from their products, and (2), that geologic processes are universally inter-related." It is a method that was elaborated by McGee* for the more recent deposits of the coastal plain of eastern United States. In its more mature statement, f correlation by this principle "becomes a juxtaposition of episodes or is a correlation by historical similarity. " "The applicatioQ of this mode of correlation involves such astudy of agencies and conditions of geologic action as to enable the geologist to determine provisionally the origin of each phenomenon examined, whether deposit or topographic feature, formation or land form: and the subsequent comparisons involved in the correlation are comparisons of genetic records, which may be made in such manner as to eliminate the incongruous and preserve the congruous, and thereby develop a consistent history for the entire province under examination. This method has already been charac- terized as homogenic, i. e., correlation by homogeny, or identification by origin. ' ' In the practical app' ication of the method, the deposits of given sections and circumscribed areas are first correlated empirically by visible con- tinuity and lithologic similarity, and to some extent by similarity of sequence, in order that their relations may be generalized; next, the agencies of genesis are inferred from the materials of the deposits viewed individually and collectively; then the unconformities and pebble-beds, * Am .lour. Sci., (3), Vol. XL, p. 36, 1890. tCong geol. ioternational, Sme Sess., p. 164, 1893. IOWA ACADEMY OP SCIENCES. 147 with other aberrant phenomena, are generalized, and from them, in con- nection with the normal deposits, the conditions of genesis {i. c , the atti- tude of land, proximity of rivery, etc.) are inferred. By these means a tangible and definite picture of the topography, geography and geologic agencies of the area is produced: and the various inferred features are tested by their consistency and the inconsistent eliminated or withheld for more extended comparison. Then the history of the contiguous area is wrought out in similar fashion and the episodes are compared severally and jointly, and the deposits and unconformities are interpi^eted in the light of this comparison. The comparison is eventually extended to other portions of the province and to the eontiguous provinces, and in each area the significance of the sum of phenomena is sought and the inferred his- tories are generalized by combination of the congruous and elimination of the incongruous until finally the history of a given period throughout the entire province is interpreted in terms of episodes each inferred from the sum of phenomena representing the period." As orig'inally suggested correlation by homogeny had long been in general use, in one phase or another, but the method had lacked definite formulation. Its main distinctive features were in emphasizing the importance of the recognition of a commitant period of land degradation, with each period of deposition and in the inference of the agencies from the materials of deposition. As set forth in its latest form, the theory has been so expanded that its vei^y name loses its significance and becomes a misnomer. Instead of designating a method of correlation it is a synonym of geological history itself. Its foundation is entirely new from what it was in the beginning and its distinctions are taken almost out of the realm of observational science and are placed in the metaphysical. In its most acceptable form, it is a special case of a more general proposition, in which refinement of determination is carried out far beyond a point where the method can be of general utility in geological work. With the older formations its use will be very limited. It is better adapted to the latest deposits, but even among these its olfice will be necessarily restricted, for with its practical use there is postulated com- paratively little effacement of the geological record of the region. Moreover, it is a method that is local in application and not general. As in the cases of lithological similarity, the biotic, and most other methods that have been commonly used, it makes no provision for correlation of provinces the geologi- cal histories of which have been not similar, but dissimilar. Historical Similarity. — Practically, this method has been in use for a long time, though not always clearly emphasized. 148 IOWA ACADEMY OF SCIENCES. It begins to show itself in the adoption of more than one method of correlation. In its latest significance, the term has come to cover the united conclusions derived from all methods of correlation. At first glance the method has much merit; but further consideration brings out the same fatal defects, in its application to general problems, that are apparent in the older and more widely used methods. It is essentially local in its extension, and hence is on the same plane as the individual methods it brings together. It fails to parallel the strata of provinces of different geological origin. Fhi/sior/raphic Develoinnent. — The modern physiographic prin- ciples, as enumerated by Davis,* Gilbert f and others, have an important bearing upon geological correlation. Their direct application, however, is confined to only the later formations. Their chief value lies in the suggestions ihey have made regarding the real basis of geological classifications and corre- lations, and in showing conclusively that a general considera- tion of the problems is not to be sought in any one of the criteria yet set forth. The fundamental principle that is of such prime importance to stratigraphical geology is that with each marked uprising of the land surface there are produced phenomena which are as ineffaceably impressed upon the portion of the earth's crust above the sea, as is deposition itself below the water level. The final reduction, through erosion of the elevated land surface, to a more or less even plain lying but little above the sea, the formation of a pene- plain, is a phase in the geological development of the region, the full force of which has been until recently entirely over- looked. When the lowland plain is depressed below tide level and covered by sediments, unconformable relations of the two formations are produced, but the line of unconformity, instead of indicating merely an hiatus, or blank gap, devoid of inter- est, represents a chapter in the history of the region that is even more pregnant of eventful happenings than those recorded by the contiguous formations that were formed during the same period. The time -gap, and not the forma- tions, are, therefore, the all-important features in marking off the ages, epochs and periods of geological history. The latter stand for continuity of record; the former for interruptions which render a classification possible. *Nat. Geog. Mag., Vol. I, pp. 183-253, 1889. + U. S. Geol. Sur., Mon. I, pp. 393-403, 1890. IOWA ACADEMY OF SCIENCES. 149 Correlation by comi^arison of the stages of physiographic development is highly important, and fertile of exact results in the later deposits, but it cannot be extended directly to the older formations, though the principle is of first importance. CORRELATION OF PROVINCES OF DISSIMILAR HISTORY. Since sedimentation goes on most actively along the borders of the great land masses of the globe, it is mainly a function of continental growth and decline. Its most important relation is with the shore-line, for the latter marks the boundary along which the process goes on. On the one side materials are being continually prepared to be carried away; on the other they are being deposited. To rising or sinking of the land with refer- ence to the sea, or to the continual advance or retreat of the shore-line, are to be ascribed all the widespread changes in the character of the deposits thrown down in any particular place, and it is the variations in level, chiefly, that give rise to the intricate succession of lithologically different layers. The immediate causes for the changes between the relations of the land and sea areas are to be sought in orogenic and epeirogenic movements. As the two kinds of movements can- not be readily separated practically, and as it is of small advantage to separate them theoretically, the results produced may be all regarded as arising from the one cause, from moun- tain-making forces. The greatest and most abrupt changes in sedimentation, and consequently in lithological, stratigraphical and f aunal, and in fact all characters, are those connected directly with diastatic changes, producing depression of some land areas below sea level, and the uprising of other districts above the level at which they once stood, forming those great surface features called mountains. Geological chronology, therefore, is believed to find a rational basis in the same processes that are involved in the genesis of mountain systems, and it is proposed to mark off the leading subdivisions of geological time, and strati- graphical succession, in accordance with the cycles of oro- graphic development, calling the classification a systematic arrangement by mountains, and the principle orotaxis By the term mountain is meant, not alone those geographic features which at the present time are so conspicuous on the surface of the earth, but also all of those structures which have in the past been prominent characters in the surface relief, and 150 IOWA ACADEMY OF SCIENCES. which are still geotectonically mountains, though they have been completely base-leveled, and have been long since buried beneath later sediments. With these old mountains the cycles of orogenic development are properly regarded as beginning at the time when the strata were compressed, and as extending through the periods when they were bowed up, then planed off nearly to sea level, and submerged perhaps, until degradational products were deposited upon their upturned edges. The record of the completed cycle of mountain- making is the measure of orotaxial chronology. The division planes cutting the geological column into systems, series, or smaller groups are, theoretically as well as actually, the lines of unconformities. In the case of the more extensive, they no doubt represent base- leveled surfaces or peneplains In all cases, great or small, the erosion plane and period of degradation of the land has its equivalent in the sea, in an accumulation of sediments. An ancient plane of unconformity, as it is now open to observation, may pass gradually into a great plane of sedimentation. In the grander unconformities, in which the plain of discordant sedimentation represents essentially an old peneplain, the corresponding stratum which was deposited in the sea area is usually a limestone. In fact, most limestone formations are now looked upon as represent- ing deposition during periods when the land adjoining was a graded surface, or a plain of faint relief lying but little above sea level This being the case, all unconformities have much greater significance than heretofore suspected. These surfaces of unconformity and their representative great planes of sedimentation are the only absolute datum planes from which the measurement of formations can be estimated. Theoretically the formation is generally con- sidered as a fixed and clearly defined unit; in practice it is found to be ill-defined and incapable of definition in any but the vaguest terms. But from the datum plane of the uncon- formity a new sequence of strata begins, sharply and clearly set off from the formations below. Many, and perhaps most, of the sharp lines of divisions are now effaced over much of the existing land surface, but in this respect the record is not more imperfect than any other, for the formations themselves have been swept away. The longer a land area has remained above sea level, the greater is the liability of the records of the earlier events being lost. Over other districts in which IOWA ACADEMY OF SCIENCES. 151 sedimentation has gone on without material interruption dur- ing an even protracted orogenic movement, the line for delimit- ing the various formations may not always be clearly discern- ible and might not, with existing data, be recognized; but with the detailed mapping of the country by the various official geological surveys, the materials are either at hand, or soon will be, for sharply defining all the places where the lines of demarkation should be properlj drawn. These lines, when once made out, and when once properly considered, are as far- reaching, and as universal in application, as those of any classificatory system probably ever can be made. Where the sequence of events has been continuous, lines drawn through the very middle of a rock succession are not entirely arbitrary, but in accord with the history more clearly recorded else- where. While orogenic movements vary greatly, both in intensity and extent, they are probably as wide reaching in their effects as any one regional force can be that is of use in geological chronology. They may be rarely or never continental — cer- tainly not world-wide in extent — but the different parts of a given continent may be successively and repeatedly affected so that a given region may be subjected to the influences from several centers of activity. The records of these movements for the continents thus overlap and interlock in such a manner that from all a moderately complete network is evolved, upon which may be arranged, in proper chronological position, the minor episodes. With the comparison of different continents, the difficulties are greater, but there are some lines which surely can be found that are common to both, just as in the case of the various provinces of a single continent. In coming down to the lesser stratigraphical groups, as the series, the stages and their subdivisions, the various sub- ordinate or local criteria of correlation may be applied in defining the several members. The leading considerations are the geographical distribution, the lithological characters, the stratigraphical delimitation, and biological definition. In dwelling upon the main characters of each stratigraphical unit, all the physical history must be incorporated. In proposing the term orotaxis, denotive of the essential feature in the scheme of geological classification and chronology above outlined, it is not with the idea of advancing an hypothe- sis that is entirely new, but rather of formulating into a 152 IOWA ACADEMY OP SCIENCES. connected whole a number of views which have long been known, somewhat vaguely as a rule, perhaps, yet which are in fact, to a certain degree at least, the real foundation of systematic geology. It is the christening of the scheme with a title in which the governing causes of sedimentation are recog- nized, in which the elements rendering possible any systematic arrangement are brought into due jn'ominence, and in which an old principle is greatly extended in its application, and is relieved of much of that which has so long overshadowed it. In general geological classification, about the only attempt in which the orotaxial principle has shown itself in the past, is in demarkation of the grand divisions or systems, and the events are commonly referred to as geological revolutions. The nearest approach to the practical application of the idea, in some of its phases, has been by Irving,* in his work on the pre-Cambrian crystallines of the Northwest, in which unconformities are given great prominence; by McGee,t in his investigations of the coastal plain deposits of the middle Atlantic slope, in which similarity of origin, or homogeny, is the governing factor; and by DavisJ and others in their physi- ographic work, in which periods of base-leveling are made the all-important features in the cycles of land degradation and the consequent sedimentation in adjoining seas. CONCLUSIONS. Proceeding upon the suggestions that have just been made, the principles of general correlation may be more clearly shown by the construction of a chart (plate vi) representing a section across the North American continent, in an east and west direction, as for instance from Richmond to San Francisco. In a diagrammatic representation of this kind, the geographic provinces are cut off by vertical lines, and the geological systems by horizontal ones, the latter being separated by dis- tances approximately proportional to the estimated time inter- val. The skeletal chart stands for continuous and uninter- rupted geological history of the continent and the stratigraphi- cal succession from the earliest to the latest formations. In the proper places are indicated some of the principal physical *IJ. S. Geol. Sur., 7th Ann. Rept., p. 378, 1888. +Am. Joup. Sci., (3), Vol. XL, pp. 36-41, 1890. *Nat. Geog. Mag., Vol. I, pp. 183-253, 1889. r 5< Co r-, 1 i 1 f^ 1 1 1 u a 1 1 "^ 1 1 Si Mississippi Basin ! T r I 1 |2 1^ Cfi p o &. 154 IOWA ACADEMY OF SCIENCES. breaks in sedimentation, or the leading cycles of mountain- making activity. These are essentially the horizons of uncon- formities, and they are extended laterally across as much territory as they approximately affected. A large number of less important unconformities are known. The whole, when thus arranged, forms an interlocking series of absolute datum planes by which may be paralleled all geological sections. The present scheme is based upon our present plan of geological chronology. In the main this is unchanged, though there is, doubtless, a considerable element of error that will have to be eliminated as the more exact determinations of parallelism are made out. The larger divisions or systems may be left very nearly the same as they are now. The minor subdivisions which cannot now be brought into juxtaposition, can readily be placed in the general scale. This appears to be one of the advantages recommending such a scheme. A PRELIMINARY LIST OF THE MOSSES OF IOWA. BY T. E SAVAGE. The mosses together with the Hepatica3 or liverworts con- stitute the group of plants known as the Bryophytes. This group is distinguished from the Thallophytes, by the fact that they present two modes of reproduction, the sexual and the asexual, which occur in regular alternation. This gives rise to what is called alternation of generations. Most bryophytes also exhibit a very fair differentiation as between stem and leaf. The spore of the moss, on germinating, produces a many- celled, branching filament containing chlorophyl, the protonema. From the protonema are developed colorless rhizoids, which penetrate the substratum, and buds which produce the stem or leafy axis of the plant. At the apices of the stems, or of the small lateral branches, are borne the sexual organs, the antheridia and archegonia. Mosses may be monoecious, the antheridia and archegonia being produced on the same plant, or dicjecious, the sexual organs being borne on separate plants. The protonema and the leafy stem with the sexual organs make up the sexual generation. IOWA ACADEMY OF SCIENCES. 155 After the egg-cell or oOsphere, which is produced within the archegonium, is fertilized by the motile antherozoid cell from the antheridium, it begins at once to divide, and develops rapidly into a capsule and stalk. During this growth the lower portion of the stalk is pressed downward into the end of the stem from which the nourishment for the asexual phase of the plant existence is derived, as in the case of a parasite. The grow- ing embryo soon ruptures the wall of the archegonium near the base, the upper part of which is carried up on top of the capsule, where it is called the calyptra. This stalked capsule or sporogonium, constitutes the asexual generation. It is less con- spicuous than the sexual phase, and is developed exclusively for the production of the spores. Mosses may be distinguished from the liverworts by the fact that in the sexual generation of the former, protonemal filaments are always well developed, on which the leafy axis is produced which shows no sign of dorsi- ventral structure. The rhizoids of mosses are usually made up of a row of cells instead of a single cell as in the Hepaticce. The mature cap sule of the mosses opens by a special lid, the operculum, which is covered by the calyptra. The columella is also present, at least in the early stages of the development of the capsule, and the mouth of the capsule usually shows a well developed peristome, consisting of one or more rows of minute teeth. Elaters, which are produced by the liverworts, are absent in the mosses. Mosses grow in shallow water, on the ground in swamps and ditches, in open fields and in shady places, on decayed logs and stumps in the woods, on rocky ledges and loose stones along streams, and on the bark of living trees. They vary in size from the small forms, a few millimeters in length, to large, floating or creeping plants, which attain a length of several inches. At no season of the year will the collector fail to be rewarded in his search for mosses. Some fruit in early spring, some in midsummer, some in the late autumn, and some may be found in fine fruit during the warmer periods of midwinter. The following list of seventy-eight species and varieties represents but an incomplete collection from a few points in the state. It is given with the hope that it may bring more to the notice of our collectors a group of plants that has hitherto been undeservedly neglected. In its preparation, the writer is 156 IOWA ACADEMY OF SCIENCES. indebted to Professor Macbride and Professor Shimek, of the State University, for kind assistance; to Mrs. Britton, of the Columbia University, and Prof essor Cheney, of Madison, Wis., for verification of doubtful forms, and also to the collectors whose names appear on the following pages. Sets of all the mosses noted below are in the herbarium of the State Univer- sity of Iowa, and also in the collections of the writer. Speci- mens of the more common species of this list have been col- lected and used in the laboratories of the university during many years. More particularly, Miss Annette Slotterbec, in 1888, collected and identified some forty specimens. But on the whole it has been deemed better to record the collection of such material only as has been gathered for the preparation of this paper. Group Bryophyta. Class Musci. Order Bryacece. True mosses. Series!. ACROCARPI. Tribe Phasce^. 1. PImscuiit (•uspidattiin Schreb. Growing on clay hillsides exposed to the sun; common in early spring. Johnson county, March 13, 1897, T. E. S. Tribe Weisie^^^:. 2. Astomum nitidulinn Schimp. On wet, marshy ground, growing among grass and weeds; rare. Johnson county, March 21, 1897, P. C. J/?/ey.s. 3. Weisia viridula Brid. Very common on the ground, fruiting throughout the year. Henry county, December 29, 1896, and Johnson county, March 13, 1897, T. E. *S'. ; Pottawatta- mie county. May, 1897, J. E. Gaiiteron. 4. Dicranella varia Schimp. On clay banks in open and exposed places; not common Johnson county, October 17, 1896, T. E. S. 5. Dicranella heteromalla Schimp. Grows on the ground, often associated with species of Barbula; common. Johnson coun'y, October, 1895, Professor Shimek: Johnson county, Octo- ber 17, 1896, T. E. N. ; Muscatine county, November 15, 1897, Shimek d- Savage. 6. DicraniDH flar/ellare Hedw. Growing on sandy hill- sides, in the shade; not commonly distributed over the state. Muscatine county, November 15, 1897, T. E. S. IOWA ACADEMY OF SCIENCES. 157 7. Dicramon scoparlum Hedw. Common on low, sandy- ground, in shaded places. Johnson county, October 10, 1896, T. E. S.: Muscatine county, November 8, 1897, Professor Shimek: Delaware county, September, iS97, J. E. Cameron. 8. Fissidens jitinutulus Sulliv. Very rare; found only in the deep ravines at Wildcat Den; on sandstone rocks near the water. Muscatine county, November In, 1897, Shimek' d- Savage. 9. Fissidens taxifolius Hedw. On damp, shaded banks near streams; not common; found only at one point. Henry county, December 28, 1896, T. E. S. 10. Leucobryioii vulgare Hampe. Plants whitish and spongy like sphagnum, with capsule and peristome resembling a Dicranum; gommon on low, shaded grounds. Johnson county, 1895, Professor Shi)iieJK: Johnson county, March 13, 1897, T. E. N.; Delaware county, September, 1897, J. E. Cameron: Mnsca- tine county, November 15, 1897, ShiinekS Savage 11. Ceratodon imrpnreus Brid. Common everywhere in exposed places on dry ground. Johnson county, May 10, 1896, and Cedar Rapids, May 15. 1896, Professor SJwnek: Johnson county, October 10, 1896, T. E. S.: Pottawattamie county. May, 1897, J. E. Cameron: Lyon county, July, 1897, Professor ()ii coinpressum Bruch. & Schimp. Not common; growing in damp places near streams, on the ground. Johnson county, May 20, 1896, Professor SJiimek. 53. ClimacUim americanum Brid. A beautiful moss, very common on damp, shady ledges of rock, or on the ground or decayed logs in damp places. Johnson county, May 20, 1896, Professor Shimek: Johnson county, October 3, 1896, and Henry county, December 28, 1896, T. E. S. : Delaware county, Septem- ber, 1897, '/. E. C imeron: Muscatine county, November 15, 1897, Shimek d- Savage: Decorah, March 24, 1898, P. C. Mfjers. Tribe Hypne^. 54. ThuicUum scitum Beauv. Not uncommon on decayed logs or on the ground in damp places. Johnson county, October, 1895, Professor Shimek: Johnson county, March 13, 1897, T. E. S. ; Muscatine county, November 15, 1897, Shimek d- Savage. 55. Thmdhim gracVe Bruch. & Schimp. On decayed logs in damp woods; less common than the preceding, from which it may be distinguished by its more turgid and nodding capsule. Muscatine county, November 15, 1897, Shimek d- Savage. 56. Thuidiiim recogiiitum Hedw. Not rare on old logs or on the ground in damp, shady places; a very beautiful form, with large, frond-like stems, which are bipinnately branched. John- son county, 1895, Professor Shimek: Johnson county, October 13, 1896, and Henry county, December 29, 1896, T. E. S.: Dela- ware county, September, 1897, J. E. Cameron: Muscatine county, November 15, 1897, Shimek <(■ Savage. 57. Tluiidium abietimrm Linn. Not common; growing on damp, shaded rocks; rarely found in fruit; the simple stems are pinnately divided into rather thick, nearly equal branches. Decorah, March 24, 1898, P. C. Mi/ers. 58. Broclnithec/ium ketum Brid. Common in woods and shaded places on the ground; capsule turgid. Johnson county, October, 1895, Professor Shimek: Johnson county, Octo- ber 13, 1896, and Henry county, December 28, 1896, T. E. S.: Keokuk, June 2, 1897, Professor Shimek: Muscatine county, November 15, 1897, Shimek <('■ Savage. 59. Brachythecivm hrtum Brid. On the ground among IOWA ACADEMY OF SCEENCES. 163 grasses a special form occurs; stems longer creeping and leaves longer acuminate than the last. Johnson county, October, 1896, Professor Shimelx. 60. Brachi/tJiecium acumiiiafum Beauv. Common in damp woods, on decayed logs. Easily distinguished by its erect capsule and rudimentary cilia. Johnson county, October, 1H94, Professor Shimek: Johnson county, September 21, 1896, 7'. E. S.: Delaware county, September, 1897, J. E. Cameron: Muscatine county, November 15, 1897, Shimek if- Savage. 61. Brachi/fheeium acuminatum setosum Sulliv. & Lesq. Branchlets slender and plumose; leaves longer than those of the last; habitat the same. Johnson county, October 17, 1896, T. E. S. 62. Brachythecium rivulare Bruch. A large moss growing in swamps and very wet places; not common. Muscatine county, November 15, 1897, Shimek d- Savage 63. Brachythecium pJumosum Swartz. Rare; growing on damp sandstone rocks and on wet ground. Muscatine county, November 15, 1897, Shimek d- Savage. 64. Eurhynchium Mans Hedw. Not rarely found on moist, shaded hillsides. Pedicel very rough. Johnson county, Sep- tember 29, 1896, T. E. S. 65. Rhynchostegium serrulatum Hedw. Very common in dry woods on the ground. Leaves two ranked. Johnson county, May, 1896, Professor Shimek: Johnson county, October 17, 1896, and Henry county, December 28, 1896, T. E. S. 66. P/agiothecium sylvaticum Huds. Rare; growing on the ground in deep shade. Johnson county, October 17, 1896, T. E. S. 67. Amblystegium serpens Linn. Common on decayed logs or on the ground in damp, shady places; stems delicate and densely branching. Johnson county, October 3, 1896, T. E S.: Pottawattamie county, May, 1897, -/. E. Cimeroii: Fort Dodge, July 5, 1897, Professor Sltimek. 68. Amblystegium irriguum Hook. & Wils. Not rare on wet ground; stems longer and coarser than the last. Johnson county. May, 1896, Professor Shimek: Muscatine county, November 15, 1897, Shimek d- Savage. 69. Amblystegium adnatum Hedw. Commonly found on trees or on stones in damp places; rare. Muscatine county, November 15, 1897, Shimek d- Savage. 70. Amblystegium riparium Linn. Very common on decayed 164 IOWA. ACADEMY OF SCIENCES. logs in damp woods and along streams; very variable. Arm- strong, July 30, 1896, and Spirit Lake, August 1, 1896, Pro- fes.wr Shimek; Johnson county, October 10, 1896, T. E. S.; Dal- las county, July 7, 1897, Professor Shimek. 71. AmbJystegium riparmm flnitans Lesq. & James. Not rare; growing in the mud or water on the borders of streams. Mason City, May 15, 1896, Professor Shimek. 72. Gampylium liispidulum Brid. Plants small and pros- trate, with deltoid acuminate leaves; common in wet places on logs or roots of trees. Mason City, July 8, 1896, and Johnson county, September, 1896, Professor Shimek. 73. HarpicUum adunc.um Hedw. Rare, stems long and float- ing; growing in water. Johnson county, 1895; and Forest City, July 20, 1896, Professor Shimek. 74. Hypnum imponens Hedw. Not common; growing on decayed logs and roots of trees in damp woods. Johnson county, August, 1895, Professor Shimek. 75. Hypnum curvifolium Hedw. Plants large, yellowish- green; leaves very crowded and strongly recurved; not rare on decayed logs in damp woods. Johnson county, October 3, 1896, T. E. S : Muscatine county, November 15, 1897, Shimek it- Savage. 76. Hypnum ha/da)iianrim Grev. Not common; growing on sandy hillsides. Muscatine county, November 15, 1897, Shimek (tj Savage. 77. Hylocomium schreberi Willd. A large moss; not rare on damp, shaded ground; stems red; leaves loosely spreading; orange at base. Henry county, December 29, 1896, and John- son county, March 13, 1897, T. E. S. 78. Hylocomium triquetrum Linn. Common on the ground and on rocks in damp, shady places; plants large; leaves squarrose. Henry county, December 28, 1896, T. E. S.: John- son county. May, 1897, Professor Shimek; Delaware county, September, 1897, -/. E. Cameron. IOWA ACADEMY OF SCIENCES. 163 ADDITIONS TO THE BIBLIOGRAPHY OF NORTH AMERICAN LICHENS. BY BRUCE FINK. While reading in the botanical library of the University of Minnesota during the summer of 1H96, I noticed a number of titles which had escaped Mr. W. W. Calkins, while preparing his bibliography of North American lichens.* These I added to some before noted in my own library and began a careful search which extended through the summers of 1897 and 1898; examining also the general library of the University of Minne- sota. The work was begun simply to find articles for my own use; but knowing the importance of having bibliographies as com- plete as possible, I have concluded to publish what additions I have been able to find. In the search for titles I have exam- ined complete files of fifteen of our leading American scientific periodicals, have looked through the best general botanical bibliographies and have consulted various miscellaneous writ- ings. Yet, I am sure that some articles have escaped me, as I know too well the difiiculties encountered in hunting for articles published in obscure places, and sometimes in papers bearing titles which do not indicate the presence of anything regarding lichens. Nearly all of the articles listed have been examined, and I have repeated four or five of Mr. Calkins' titles because very imperfectly cited. I have brought my list only to the date of his publication, and in a future paper I shall hope to bring his paper, my additions and any other titles that I may be able to find, together for greater convenience of reference and to con- tinue the work to include the list of papers published since April 15, 1896, the date to which his bibliography extends. I have attempted to follow, in general, the rules of citation of the Madison Botanical consrress. *Oalkins, W. W. Bibliography of North American Lichenology, Chicago Acad. Sci. 1 : 44-50, April 1896. 166 IOWA ACADEMY OF SCIENCES. LIST OF ARTICLES. 1. Arthur, J. C. Flora of Floyd county, Iowa. Bot. Gaz. 7: 127. N 18H2. The paper was published in a history of Floyd county and contained only a popular statement about the lichens. 2. Bessey, C. E. Preliminary List of the Carpophytes of the Ames Flora. Bull. Iowa Agr. College. 141--148. N 1884. Gives a list of twenty-four lichens. 3. . The Study of Lichens. Am. Nat. 21 : 666-667. Jl 1887. 4. Eby, Amelia F. Preliminary List of the Lichens of Lancaster County, Pennsylvania. Pamphlet, 5. 29 Ja 1H94. 5. . Reprint of the Preliminary List of Lichens of Lancaster County, Pennsylvania. Pamphlet, 17. 7 Mr 1894. 6. . A List of Lichens and a Partial List of Fungi Collected in Lancaster County, Pennsylvania. Pamphlet, 18. 22 O 1894. 7. Darlington, W. Flora Cestrica, an Herborizing Com- panion for the Young Botanists of Chester County, Pennsyl- vania, Philadelphia: pp. 431-456. 1883. 105 species, deter- mined by E. Michener, are enumerated with short descriptions. 8. Eaton, A. Manual of Botany of North America, Albany, 1817. Contains descriptions of some lichens. 9. Eckfeldt, J. W. Notes on the Lichens in the Herba- rium of the Philadelphia Academy of Science. Proc. Acad. Sci. Phil. : 342-343. 1886. 10. . . Some New North American Lichens. Bull. Torr. Bot. Club 16: 104-106. Ap 1889. Gives six of Dr. W. Nylander's descriptions of new North American lichens. 11. . A further enumeration of some Lichens of the United States. Bull. Torr Bot. Club 17: 255-257. 9 O 1890. Gives descriptions of ten species. 12. . A Lichen new to the United States, Alectoria cefrariza. Nyl. Bull. Torr. Bot. Club 18: 257. 8 Au 1891. 13. . In list of plants collected by the United States steamer Albatross, in 1887-1891, along the western coast of America, Cont. Nat. Herb. 1: 70-79. 1892. Lichens by Elk- feldt. IOWA ACADEMY OF SCIENCES. 167 14. . Lichens new to North America. Bull. Torr. Bot. Club 21 : 393-396. 29 S 1894. Describes nine new species. 15. . In Rand, E. L. and Redfield, J. H. Flora, of Mt. Desert Island, Maine. John Wilson & Son, Cambridge, Mass., 1894 A list of 280 species and varieties of lichens from Mt. Desert and adjacent islands. 16. Farlow, W. G. Memoir of Edward T acker man. Pam- phlet, read before the National Academy, April, 1887. 14. Judd & Detweiler, printers, Washington, D. C. 17. ■—. The Collection of Lichens belonging to the Boston Society of Natural History. Proc. Boston Soc. Nat. Hist. 274-275. 1888. Read, February 17, 1886. 18. Fink, Bruce. Lichens collected by Dr. C. C. Parry in Wisconsin and Minnesota in 1848. Proc. Iowa Acad. Sci 2: 137. 1895. 19. . Lichens of Iowa (exsiccati). Fayette, Iowa, 1S95-1898, — 100 sets of 100 to 150 species each, have been distributed in America and Europe. 20. Gray, A. Memoir of Edward Tuckerman. Am. Jour. Sci. and Arts 132: 1-7. Jl 1886. 21. Green, H. A. A new Lichen. Bot. Gaz. 12: 115. My 1887. Gives H. Willey's description of Buellia cutawbeusis. 22. Harvey, F. L. Contributions to the Lichens of Maine, I. Bull. Torr. Bot Club 21: 389-393. 29 S 1894. List of 115 species. 23. . Contributions to the Lichens of Maine, IL Bull. Torr. Bot. Club 23: 7-10. 30 Ja 1896. List of 114 species. 24. Heller, A. A. Preliminary Enumeration of the Lichens of Lancaster County, Pennsylvania. Pamphlet, Lancaster, Pa 15 F 1893. 25. Hooker, W. J., in Kunth, C. S. Synopsis quas in Itinere ad Plagam gequinoctialem Orbis novi coUegerunt A. de Humboldt et A Bonpland. Paris. 1832-1835. Short descrip- tions of seventy-five species, eleven new. 26. Krempelhuber,A. V. Verzeichniss der Lichenen welche M. Wagner auf seinem Reisen in Central Amerika wiihrend der Jahre 1858 und 1859, gesammelt hat. Flora 19: (new series) 129- 134. 7 Mr 1861. Lists thirty-five species, one new. 168 IOWA ACADEMY OF SCIENCES. 27. — . Geschichte liber Literatur der Lich- enologie von den iiltesten Zeiten bis 1870. Miinchen 1867-1872. Contains numerous references to American writings and writers. 28. . Lichenes Mexicani quas legit 1875, R. Rabenhorst Hedwigia 15: 148-149. O 1876. Lists twenty- eight lichens, Verrucaria f etivica Krphb , described as new. 29. Michaux, A. Flora Boreali — Americana, sistens charac- ters plantarum, quas in America septentrionali coUegit et detexit, Paris, 1803. Mentions twenty-one species from Caro- lina and Canada, seven new. 30. Meyer, E. De plantis Labradoricis libritres, Lipsise, 1830. Mentions seventeen lichens. 31. Mtlller, J. Lichenogische Beitrage, Lichenes aus Texas, Flora 60: 77-80. 11 F 1877. Lists 41 species and varieties and describes five of them as new. 32. . Lichenogische Beitrage, Flora 61: 481-492. 1 N 1878; 64: 225-236. 21 My issi; 65:291-306,316-322. 1 Jl, 11 Jl 1882; 66: 286-290, 317-322, 344-354. 21 Je, 11 Jl, 1 Au 1883; 67: 268-274, 283-289. 11 My, 21, My 1884; 68: 324- 326, 331-342. 1 Je, 11 Je 1885; 69: 286-290. 21 Je 1886; 70: 56-64, 336-338. 1 F, 21 Jl 1887. A series of articles of various titles, of which the above numbers at least give names or descriptions of North America lichens. Some are described as new. '^3. . Lichens Oregonensis in Rocky Moun- tains, Washington Territory, insula Vancouver et territories vicinis Americas occidentalis a cl; Dr. Julio Roell anno praeter lapso lecti et a cl; Dr. Dieck communicata, quos determinavit. Flora 72: 362-366. 20 Jl 1889. Lists eighty-one species and gives a description of a new variety. 34. . Lichenes Exotice. Hedwigia 34: 139-145. Je 1895. Some mention of North American lichens. 35. Nylander, W. Lichenes collecti in Mexico a Fr. Mtiller. Flora 41: 377-379. 28 Je 1858. Determination of 110 Mexican species. 36. . Expositio Pyrenocarpeorum. Ande- cavis, 1858. North American species mentioned. 37. . Synopsis MethodicaLychenum; Paris, 1858-1860. Contains numerous references to North American lichens. IOWA ACADEMY OF SCIENCES. 169 38. . Observationes paucse circa Scripta lichenologica recentissima. Flora 43: pp. 41 44. 21 Ja 1860. Comments on Tuckerman's "Supplement to an Enumeration of North American Lichens. " 39. . Conspectus Squamariarum. Flora 44: pp. 716-718. 7 D 1861. Mentions North American species. 40. . Enumeratio synoptica Stictarum. Flora 48: 296-299. 23 Je 1865. Mentions North American species. 41 . . In Cryptogama3 Mexicanas nuper a collec- toribus Expeditionis scientif. allatse aut in Museo. Paris depositee. A volume of 166 pages. Paris, 1872. Lichens by Ny lander. 42. . Arthonise novae Americanae, borealis. Flora 68: 311-313. 1 Je 1885. Describes six species. 43. . Enumeratio Lichenum, freti Behringii. Bull. Soc. Linn. Normandie: (4*^ Ser.) 189-286, 1887. Mentions some American species and names A/ectoria cefrariza Nyl. 44. Petiver, Joe. Pterographia Americana, icones con- tinens Filicum nee non Muscos, Lichenes, Fungos, etc. Lon- don, 1712. Refers to a single lichen, Stkta damax-ornis (Auct.). 45. Plumier, Carol. Filicetum Americanum senfilicum, etc. in America nascent. Paris, 1703. Also mentions SUcta damcecoruis (Auct.). 46. Porcher, F. P. The Medicinal, Poisonous and Dietetic Properties of the Cryptogamic Plants of the United States. Trans. American Medical association 7: 167-284. 1854; pp. 179- 192, give notes on fifty-one lichens, with uses to which they have been put, and methods of preparing them for the various uses. 47. Pound, R. The Algae, Fungi and Lichens. Am. Nat. 23: 178. F 1889. 48. Rau, E. A. A Lichen new to the United States. Jour, of Mycology 4: 20. F 1888. A note on Trypethelium heterochrous. 49. Sargent, F. L., in How to collect certain Plants. Bot. Gaz. 11: 142. Je 1886. By several writers; Mr. Sargent treat- ing lichens. 50. , Guide to the Recognition of the Princi- pal Orders of Cryptogams and the commoner and more easily distinguished New England Genera, with Glossary. Pamphlet, 170 IOWA ACADEMY OF SCIENCES. 39. C. W. Sever, Cambriclg-e, Mass. 1886. Contains descriptions of thirty-one common lichens. 51. . On the Schwendener Theory of tlae con- stitution of Lichens. Am. Mo. Mic. Jour. 8: 21-25. F 1887. 52. . About Lichens, Pop. Sci. News 26: 50- 52, 65-67. Ap, My 1892. (Illustrated Figs. 17.) A popular article for beginners in the study of lichens. 53. . A Key to the North American Species of Cladonia. Cambridge, Mass., 1893. A quarto blue-print. 54. Schneider, A. A. Monograph of Lichens. Bull. Torr. Bot. Club 21 : 492-493. 24 N 1894. A review of J. M. Crombie's British Lichens. 55. — . Contributions to Lichenology. Bull. Torr. Bot. Club 21: 532-534. 24 D 1894. A review of J. Reinke's " Abhandlungen iiber Fletchen. " 56. . The Biological Status of Lichens. Bull. Torr. Bot. Club 22: 189-198. 15 My 1895. 57. . Some special Polygenetic Adaptations in Lichens. Bull. Torr. Bot. Club 22: 498-500. 30 D 1895. 58. Stirton, J. Lichens, British and foreign. Trans. Glasgow Soc. of Field Nature. 85-95. 1875. Mentions species from Montreal and Lake Superior. 59 Stitzenberger, E. De Lecanora subfusca ej usque formis Commentatio, Botanische Zeitung 26: 888-902. 25 D 1868. Mentions North American varieties. 60 — . Notes on western Lichens. Erythea 3: 30-32. 1 F 1895. Lists thirty-five Lichens from Yellow- stone Park, Monterey & Sitka. 61. Tucker man, E. An enumeration of some Lichens of New England, with remarks. Boston Jour. Nat. Hist. 2: 245-262. 1839. Gives forty-three species and varieties. 62. . A further enumeration of some New England Licheaes. Boston Jour. Nat. Hist. 3: 281-306. 18 H. Gives sixty-eight species and varieties. 63. . Further notices of some New Eagland Lichenes. Boston Jour. Nat. Hist. 3: 438-448. 1841. Gives twenty-six species. 64. . A further enumeration of some Alpine and other Lichenes of New England. Boston Jour. Bot. 5: 93-104. Ja 1845. Giv^es thirty-one species. 65. . Lichenes Americani septentrionalis exsiccati. Fasc. I-VI. Cambridge and Boston. 1847-1854. IOWA ACADEMY OF SCIENCES. 171 Reached 150 numbers. Short notices of these will be found as follows: Botanische Zeitung 7: 533. 20 Jl 1849; Flora 15: (new series) 88. 14 F. 1851; 18: 173-175. 21 Mr 1860. 66. . A synopsis of the Lichens of the north- ern United States and British America. Proc Am Acad. Arts and Sci. 1 : 195-285. 1848. Read December 7, 1847. Describes 275 species. 67. ; in Lea, T. G. Catalogue of the plants, native and naturalized, collected in the vicinity of Cincinnati, O., during the years 1834-1844; Philadelphia, 1846. List of fifty-three species; one new. 68. , in Agassiz, L. Lake Superior, its Physical Character, Vegetation and Animals, Compared With Those of Other and Similar Regions. Boston. 170-174. Mr 1850. List of seventy-two species and varieties; four new. 69. . Supplement to an Enumeration of North American Lichenes. Amer. Jour. Sci. and Arts (second series) 25: pp. 422-430. 1856. Short descriptions of thirty-nine new North American lichens. 70. . Supplement continued. Amer. Jour. Sci. and Arts 28: 200-206. 1857. Describes twenty- two new North American lichens. 71. Observations on North American and Some Other Lichens. Proc. Am. Acad. Arts and Sci. 4: 383-407. 1860. Notes on fifty-one species and varieties, including descriptions of four new ones. 72. . Observations on North American and Some Other Lichens. Proc. Am. Acad. Arts and Sci. 5: 383-422. 1862 Notes on fifty-five species and varieties; about two-thirds new. 73. Observationes Lichenologicse. Proc. Am. Acad. Arts and Sci. 12: 263-287.1866. (Read April 12, 1864.) Treats of forty-eight species, thirty-seven being new. 74. . Lecidea elabens Fr. Flora 58: 63-64. 1 F 1875. A note concerning. 75. . Observationes Lichenologicse. Proc. Am. Acad. Arts and Sci. 12: 166-185. 1877. Notes on forty- three species and varieties, thirty-one being new. 76. . List of Lichens collected in the vicinity of Annanactook harbor, Cumberland Sound about Lat. 67° N. , Long. 68° 49' W. Bull. United States Nat. Mus. 15: 167-168. 1879. Lists fifty-three lichens. 172 IOWA ACADEMY OF SCIENCES. 78. . The Question of the Gonidia of Lichens. Am. Jour. Sci. and Arts 17: III. 254-256. Mr ls7i). 79. . Lichens or Fungi. Bull. Torr. Bot. Club 7: 66-67. Je 1881. 80. . Review of Minks' Symbolse Lichenes, Micologicse. Bull. Torr. Bot. Club 9: 143. N 1882. 81. . New western Lichens. Bull. Torr. Bot. Club 10: 21-23. F 1883. Describes Leridsa brandegei Tuck and Pi/renothalmnia spragei Tuck, from the Pacific coast. 82. . A new Ramalina. Bull. Torr. Bot. Club 10: 43. Ap 1883. Describes Ramalina. crlnlta Tuck. 83. . Two Lichens of the Pacific coast. Bull. Torr. Bot. Club 11: 25, 26. Mr 1884. Comments on Lecanora melanasim Sch. and describes Sfaurothe/e brandegei Tuck. 84. Waite, M. B. Experiments with Fungicides in the Removal of Lichens from pear trees. Jour. Mycology 7: 264- 268. 1893. (Illustrated. Plates 1 and 2.) 85. Williams, T. A. The Status of the Algo-Lichen Hypothesis, Amer. Nat. 23: 1-8. Ja 1889. 86. . Notes on Nebraska Lichens. Amer. Nat. 23: 161. Mr 1889. Short note as to general character of the lichens of the state. 87. . Notes on the Canyon Flora of North- west Nebraska. Amer. Nat. 24: 779-780. Au 1890 Notices of some lichens included. 88. Willey, H. A new North American Lichen. Bull. Torr. Bot. Club 8: 140-141. D 1881. Describes Omphalodium hottentoftnm (Ach.) F lot. var. arizonicum Tuck. 89. -. GyalectalamprosporaNyl. Bull. Torr. Bot. Club 2: 61-62. Je 1885. 90. . New North American Arthonise. Bull. Torr. Bot. Club 12: 113-115. N 1885. Gives descriptions of twelve species. 91. . Edward Tuckerman. Bot. Gaz. 11: 73- 78. Mr 1886. 92. . Dermatiscum, a further note concerning. Bull. Torr. Bot. Club 14: 222. 4 O 1887. 93. . Nylander's Synopsis. 1 : Bull. Torr. Bot. Club 14: 222. 4 O 1887. 94. . Enumeration of the Lichens found in New Bedford, Mass., and its vicinity, from 1862 to IOWA ACADEMY OF SCIENCES. 173 1892. Pamphlet, 29. E. Antony & Son, New Bedford, Mass., 1892. A list of almost 500 species and varieties with copious notes and three or four new species described. 95. Wilson, L. A. An Artificial Key to Lichens. Am. Mo. Mic. Jour. 16: 65-80. Mr 1895. THE FLORA OF SOUTHERN IOWA. BY T. J. AND M. F. L. FITZPATRICK. II. On June 20, 1898, the first writer of this article started over- land from Lamoni to Council Blulfs, in company with Prof. J. T. Pence. The route taken passed through the west side of Decatur county to Hopeville, in the southwest part of Clarke county, thence bearing west to Afton in Union county, on to Creston in the same county. As near as practicable the line of the Chicago, Burlington & Quincy railway was followed through Adams county, bearing southward with the railway to Villisca and northward to Red Oak in Montgomery county. From Red Oak a nearly northerly direction was taken until into Pottawattamie county, then westward to Wheeler and north- westward to Carson, where the overland trip, as far as this article is concerned, ended. Carson was reached June 24th. The five days of the journey were filled with frequent stops in order to collect by the wayside and from adjoining groves and fields. A week was spent at Carson collecting in the immedi- ate vicinity and in Wheeler 's grove. On July 25th, the writer in company with J. P. Anderson, an ex-student of the Nebraska State University, left Lamoni in a covered wagon for an overland trip to Nebraska City, Neb. The route taken beyond Decatur county, was through the southern portions of Ringgold, Taylor, Page and Fremont counties, passing through in succession Caledonia, Redding, Blockton, Bedford, Shambaugh, Coin, Riverton, through the hills west of Riverton and across the valley to Nebraska City, Neb. An entire week was taken for the journey. Material was collected from the waysides and adjoining streams or occa- sionally covering the rougher uplands. From Nebraska City 174 IOWA ACADEMY OF SCIENCES. we passed northward through Otoe county and stopped in Cass county, Neb., opposite McPaul, Iowa. Here two weeks were spent drying material and collecting on the Nebraska side of the river or on the Iowa side around McPaul. Wabonsie slough, which is mostly the remains of a lake about two miles north of McPaul, gave us many good specimens. On August 25th we started from Nebraska City on our return. The route chosen was northwesterly across the valley and through the hills to Sidney in Fremont county, thence eastward to Clarinda, Page county; on across Taylor county to Mt. Ayr, in Ringgold county, the road scarcely varying a mile north or south from a due east and west line, the entire distance from Sidney to Mt. Ayr. From Mt. Ayr we turned southerly, toward Lamoni, arriving. on the 18th of August. The following list of species is the result of the trips here described and the additional species found in Decatur county since our last paper was written. The specimens are deposited in the private herbarium of T. J. and M. F. L. Fitzpatrick. The list is by no means complete but represents very well the flora of the region for the period of time covered. The order Leguminoste is fairly well represented, midsummer being the time of its greatest development, while the great order Com- positse has only fairly started by the latter part of August. The spring flora had passed out by the time we began work. The rectangle formed by the six counties, Union, Adams, Montgomery, Ringgold, Taylor and Page, presents much in common. A great portion of this region is an expanse of rolling prairie. Level ground is rarely seen save in the narrow bottoms or highest uplands. The ground near the streams rolls heavily, but gradually reduces to long swells as we go farther from the streams. Much of the land appears as long narrow ridges running parallel with the streams and flanked at sharp intervals with small lateral ones. The ridges are of the typical Kansas drift, covered with a thin black or blackish soil, while the valleys are alluvium, deposited from overflows of the streams or carried down from the uplands by surface wash. Grand river and its tributaries cross diagonally the east- ern portion of Union county, rolling southeasterly; Ringgold county is drained by the west fork of the Grand and Platte rivers, and their tributaries, rolling southwesterly. The southeastern portion of Union county is drained by the same IOWA AC VDEMY OF SCIENCES. 175 system. The divide, separating these two systems, passes southeasterly across the center of Union county, thence south- ward near the line of Decatur and Ringgold counties. Adams county rolls southwesterly and is drained by the Nodaway system, which system also drains the eastern portion of Mont- gomery and Page counties, the river system flexing from a southwesterly to a southerly direction, in the southeastern portion of Montgomery county. Taylor county has the Piatt river system, and rolls to the southward. The western portion of Montgomery county is drained b}^ the Nishnabotany system, which runs southwesterly, crossing the northeastern portion of Page county; thence bearing westward to Riverton, in Fremont county, where the different systems of the Nishnabotany unite into a single stream; the whole system lies east of the loess hills which border the Missouri river bot- toms. The river systems of the rectangle, in general, flow southwest, except in the extreme eastern portion, where they flow southeast. The whole county is cut into numerous north and south divides by the many tributaries of the Piatt. Throughout this rectangle of six counties, the flora presents a complex nature, which is common throughout the region. The native flora is much restricted in extent, though it persists in many portions where the primeval sod has as yet been unfurrowed. The waysides, the narrow strips along the rail- way, and portions next the back settlements, still grow the original prairie grass and the accompanying flora, while many similar tracts are continuously pastured, and present little flora, except here and there a thicket. In this region the western flora is passing eastward and the eastern flora westward. Many species, on their tramps in opposite directions, seem to have met in this region, and established themselves, and to have become an integral part of the flora. Examples of the western forms are Lactuca puJchella D. C, Plantago aristata Mx., Solanum7'ostratum Dunal., Hordeum pusUlinn Nutt., and many others as will be seen from the list. Among those moving westward are the Lepidiums, Brassica nigra Koch., Capsella bursa- pastor is Moench., Xanthium canadense Mill., Ambrosia arteiaiscefoUa L., and A. trifida L., AntJwmis cotula D. C, Datura stramonium Li. and D. tatula L , all of which are becoming conspicuous in the waste land through- out the region. The prairie portions yield Silphiums, Heli- anths, Liliums, Psoraleas, Anemones, Ceanothus, Asters, and 176 IOWA ACADEMY OF SCIENCES. Solidagos, the two latter genera appearing in their best development a month later than the time of our explorations. The bottoms of the small rivers or streams frequently have marshes, or long ponds, formed from old river beds. Here may be found Typha, Sagittaria, Lemna, Sparganiuhi, and other water plants hereafter listed. The woods were composed of elms, oaks, cottonwoods, linn, an occasional sycamore, and great abundance of willows in the lowlands. The older trees have mostly been pressed into use for local purposes. The woods are largely made up of young trees. Upland thickets are common and are mostly composed of hazel, red haws, sumac, plum, buckthorn, bittersweet, and shrubby oaks. The flora is much restricted by agricultural operations, which yearly reduce the amount of free ground for the native flora, while more careful culture renders difficult the existence of the introduced flora which, however, takes refuge in waste lots and along fence-ways and borders. The native flora takes refuge in the railway right of way, where the plants have been enjoying a brief respite, but will, ere long, either be com- pelled to turn tramps or cease to exist. The counties west of the rectangle have many species peculiar to that portion of Iowa. The bluffs bordering the Missouri river valley are composed of a remarkable series of loess hills. The flora of these hills includes Yuccas, Legumes, and grasses that are not found anywhere else in Iowa. The valley of the river has quite a number of introduced plants, common enough now, and which are migrating, and destined to extend from here eastward and become a source of trouble to farmers. In the preparation of this paper we are indebted to Mr. J. P. Anderson, of Lamoni, Iowa, for constant assistance as a col- lector. To R. I. Cratty, F. Lamson-Scribner, and the officers of the Missouri Botanical Garden, we are under obligations for determinations of difficult species. We present the results of our labors, and hope they are worthy as a contribution to a better knowledge of the flora of this portion of Iowa. Lamoni, Iowa, January 1, 1899. Ranunculace^. (lematls vlrfjlnlana L. Union, Ringgold, and Page counties. Thickets and waysides; frequent. IOWA ACADEMY OF SCIENCES. 177 C. intcheri T. & G. Union, Fremont, and Pottawattamie counties. Thickets; frequent. Anemone cylindrica Gray. Union, Ringgold, Fremont, Adams, Montgomery, and Pottawattamie counties. Prairies, waysides; frequent. A. virglniana L. Ringgold, Page, and Fremont counties. Woods; frequent. A. pemhsylvanica L. Ringgold and Pottawattamie counties. Prairie; frequent. Thalictrum imrpurascens L. Union, Ringgold, Page, Taylor, Fremont, Adams, and Pottawattamie counties. Open woods; frequent. Ranunculus multifldus Pursh. Decatur county. A few speci- mens found in a moist locality. Aquilegia canadensis L. Ringgold and Pottawattamie coun- ties. Woods; common. Delphinium tricorneMx. Clarke, Union, and Decatur counties. Fields and woods; moist places; common. Many specimens were found with double flowers, the two upper petals, as usual, and six others, the lower sepal spurred similar to the upper, but with a smaller spur. Specimens with six or seven petals were also found. D. azureum Mx Clarke, Union, Adams, Montgomery, and Pottawattamie counties. Prairies; common. Memispermace.e. Menispermum canadense L. Union, Ringgold, Page, Taylor, Fremont, and Pottawattamie counties. Woods; common. Berberidace^. Podophi/Uum peltatum L Union and Ringgold counties. Rich woods; common. NYMPH^ACEyE. Nympluva tuberosa Paine. Fremont county. Common in Wabonsie slough. Crucifer.^. Arabis canadensis L, Page county. Woods; infrequent. A. dentata T. & G. Decatur county. One specimen found. Nasturtium sinuatum Nutt. Fremont county. This species is a very common weed in the Missouri river bottoms. N. sessiliflorum Nutt. Decatur and Page counties. Low, wet places; frequent. 12 178 IOWA ACADEMY OF SCIENCES. N. palustreJ). G. Union county. Moist places; common. N. armoracia Fries. Adams county. Waste places; com- mon. Er>/iintt. Clarke, Adams Montgomery, Potta- wattamie, Page, Ringgold, Taylor, and Fremont counties. Waysides; common. A. fruticosa L. Clarke, Adams, Montgomery, Pottawattamie, Ringgold, Taylor, and Fremont counties. Sloughs and along streams; common. A. micj^ophyUa Pursh. Decatur county. Dry upland woods, infrequent, Dalea laxiflora Pursh. Fremont county. Loess hills, com- mon. PetaJostemon violaceus Mx. Ringgold, Taylor, and Fremont counties. Prairies; frequent. P. Candidas Mx. Ringgold, Page, and Fremont counties. Prairies; frequent. Kobinia pseudacacla L. Taylor and Montgomery counties. Appearing as escapes; frequent. Astragalus canadensis L. Ringgold, Taylor, Page, and Fre- mont counties. Damp soil; common. Oxi/tropus lambirfi Pursh. Fremont county. Loess hills, common. Glycyrrhiza. lepidota Nutt. Union, Taylor, and Montgomery counties. Waysides; common. Desmodiuni acuminatum DC. Ringgold, Page, and Fremont counties. Rich woods; common. D. illinoense Gray. Ringgold and Page counties. Prairies; frequent. D. paniculatum DC. Decatur and Fremont counties. Woods; infrequent. D. canadense DC. Ringgold and Page counties. Oj^en woods; frequent. /). diUenii Darlingt. Fremont county. Woods; frequent. Lespedeza violacea Pers. Ringgold and Page counties. Prairies; frequent. L. reticulata Pers. Dry, upland woods; infrequent />. capitata Mx. Ringgold, Page, and Fremont counties. Dry soil; common. Ajnos tuberosa Moench. Ringgold, Taylor, and Fremont counties. Strop] iostyles angulosa. Ell. Fremont county. Sandy soil; common. S. Pauciflorus Watson. Fremont county. Sandy soil; fre- quent. IOWA ACADEMY OF SCIENCES. 183 AmpMcarjma monoica Nutt. Page county. Dry woods; frequent. A. intcheri T. & G. Page and Pottawattamie counties. Woods; frequent. Gercis canadensis L. Fremont county. Frequent. Cassia marylandica L Ringgold, Page, and Fremont coun- ties. Rich lowlands; frequent; in some localities forming thickets; found also in Otoe and Cass counties, Nebraska. ('. chama'crista L. Ringgold, Page, Taylor, Fremont, Mont- gomery, and Pottawattamie counties; waste places; common. Gymnodadus canadinsis Lam. Fremont and Pottawattamie counties; low woods; infrequent. GledetscMa triacanthos L. Adams, Ringgold, Taylor, Page, and Fremont counties. Desmanthus bracJtylobus Benth. Fremont county; foot of loess hills and bottoms of the river; common. Rosace.^. Prunus amencana Marsh. Clarke, Union, Adams, Taylor, and Pottawattamie counties; thickets; common. L\ sertina. Ehrh. Union, Adams, Montgomery, Pattawatta- mie, Ringgold, Page, Taylor, and Fremont counties; woods: frequent. P. virginiana L. Clarke, Adams, and Pottawattamie counties; low woods; frequent. Sjnrcea salicifoUa L. Taylor and Page counties; waysides; infrequent. liubus occidentalis L. Clarke, Ringgold, Fremont, and Pot- tawattamie counties; waysides, thickets; frequent. Pi. villosus Ait. Union, Ringgold, and Fremont counties: open woods; frequent. Geum album Gmelin. Ringgold, Page, and Pottawattamie counties. PotenWIa arguta Pursh. Ringgold county; prairies; common. P. norvegica L. Ringgold county; fields; common, Agrimonia eupatoria L. Ringgold, and Fremont counties; open woods; common. A parviflora Ait. Page and Ringgold counties: low prairies: frequent. Bosa arkansana Porter. Clarke, Union, Adams, Montgomery, Pottawattamie, Ringgold, Page, and Fremont counties: prairies: common. 184 IOWA ACADEMY OP SCIENCES. Pyi'us coronaria'L. Clarke, Union, Adams, Montgomery, Pot- tawattamie, Ringgold, Page, and Taylor counties; thickets; common. P. malus L. Union, Page, Adams, Montgomery, Pottawatta- mie, and Ringgold counties; waysides; frequent; appearing mostly as low shrubs. Crataegus coccinea L. Clarke, Adams, Taylor, and Pottawat- tamie counties; thickets; common. C. crus-gaUl L. Clarke and Page counties; woods; frequent. Amygdalus jiersica L. Ringgold, Taylor, Page, and Fremont counties; waysides; waste places; frequent; an escape from cul- tivation. Saxifragace.?!:. Heuchera li'ispida Pursh. Union and Adams counties; prairie; frequent. Parnassia caroliniana Mx. Johnson county; frequent locally. Bibes gracile Mx. Clarke, Union, Adams, Pottawattamie, and Fremont counties; woods; common i?. floridum L'Her. Taylor county; a clump by the wayside. Crassulace^e. Pentliorum sedoides L. Ringgold and Taylor counties; damp soils; common. Halorage.e. MyriophyUum scabratum Mx. Ringgold county; common in a lake near Delphos. In Wabonsie slough, in Fremont county, a deep water form was found that is taken to be this species. CaUitricha heferophy/la Pursh. Decatur county; a few speci- mens found in moist localities. This is a rare plant for Iowa, and even a rare genus. The only other species we have is (,'. verna L., of Muscatine county, collected by F. Reppert. Lythrace.'E. Ammannia coccinea Rottb. Decatur county; about a dozen specimens found on the margin of a railroad pond near Davis City. Lythrum alatnm Pursh. Union, Adams, Montgomery, Ring- gold, Page, Taylor, and Fremont counties; moist soil; com- mon. Didiplis linearis Raf . Decatur county; a few specimens on the margin of a railroad pond near Davis City; this species was quite common on mud Hats of a lake near Benton, Ringgold county, where it was collected in quantity. IOWA ACADEMY OF SCIENCES. 185 Onagkace.-e. Ludwigia polycarpa Short & Peter. Ringgold, and Taylor counties. Shallow lakes; frequent. Gaura biennis L. Fremont county. Fields and waste places; common. By a clerical error G. coccinea Nutt. was given for this species in the last Academy report. The local- ities for southern and. northeastern Iowa should be credited to this species. G. parviflora Dougl. Fremont county. Base of loess hills and in bottoms; frequent. Oenothera biennis L. Ringgold and Fremont counties. Fields; common. Circcea lutetiana L. Page, Ringgold, Fremont, and Potta- wattamie counties. CUCURBITACE^. Ediinocystis lobata. Taylor, Page, and Fremont counties. Umbellifer.^. Cicuta maculata L. Ringgold, Taylor, and Fremont counties. Moist places; common. Tiedemannia rigida Coult. & Rose. Ringgold county. Wet sloughs; frequent. Heracleum lanatum Mx. Union and Pottawattamie counties. Rich woods; common. Pastinaca sativa L. Decatur, Clarke, Union, Adams, Ring- gold, Taylor, Page, Fremont, and Johnson counties. Waste places; common. Piiiipinella integerrima. Union county. Woods; frequent. Point cenia nuttaUii DC. Ringgold and Montgomery counties; prairies; a few specimens found. Crijptotxenia canadensis DC. Union, Ringgold, and Potta- awattamie counties; woods; common. Sium Gicutiefolium Gmelin. Ringgold county; wet soil; f re quent. Zizia aurea Koch. Johnson and Page counties; low grounds; common. Osmorrhiza brevistylis DC. Fremont county; woods; frequent. 0. longistylis DC. Fremont county; woods; frequent. Eryngium yacccefolium Mx. Montgomery, Pottawattamie, Ringgold, Taylor, and Page counties; prairies; common. Sanicula marylandica L. Ringgold and Pottawattamie counties; woods; common. 186 IOWA ACADEMY OF SCIENCES. CORNACE.E. Cornus asperlfolia Mx. Taylor, Fremont, Montgomery, and Pottawattamie counties; thickets; common. (J. sericea L. Adams county; low places; common. 0. paniculata L ' Her. Ringgold and Pottawattamie counties. C. alternifolia L. Johnson county; one shrub, from which several specimens were collected, is known. Caprifoliacete. Sambucus canadensw L. Clarke, Union, Adams, Montgom- ery, Pottawattamie, Ringgold, Taylor, Page, and Fremont counties. Low grounds; common. Ylbuniuin jmbescens Pursh. Decatur county. Upland thick- ets; frequent locally. V. lentago L. Union and Decatur counties. Low ground, along streams; frequent. V. pi'^'iiifo^ii'iif L- Johnson county. Low grounds; infre- quent. T'. dentatwn L. Johnson county. Wooded ravines; infre- quent. Triosteum. perfollatiun L. Union, Adams, Pottawattamie, Ringgold, and Page counties. Woods; common. Symphoricarpos vulgaris Mx. Clarke, Union, Adams, Mont- gomery, Pottawattamie, Lucas, Monroe, Ringgold, Taylor, Page, and Fremont counties. Upland woods and prairies; common. S. occideiitd/is Hook. Fremont and Pottawattamie counties. Base of loess hills; common. Lonicera sulUvantll Gray. Fremont county. Woods; a few collected. RUBIACE^. Houstonia angmtifoUa Mx. Taylor and Fremont counties. Prairies and loess hills; common. Galium concinmoii T. & G. Union and Page counties. Woods; common. G. circcezans Mx. Fremont and Pottawattamie counties. Woods; common. COMPOSIT.^.. Vernonia. noveboracensis latifolia Gray. Ringgold county. Pastures; common. Eupatorium purpmreum L. Ringgold, Page, and Pottawat- tamie counties. Woods; common. IOWA ACADEMY OF SCIENCES. 187 Liatris punctata Hook. Fremont county. Loess hills; common. L. scariosa Willd. Ringgold and Fremont counties. Prai- ries; common. L. jn/cnostacJii/a Mx. Ringgold, Taylor, and Page counties. Prairies; common. L. squarrosa Willd. Taylor and Page counties. Prairies; common. GrindeUa squarrosa DmidA. Fremont county. Waste places; frequent. SoUdago rig Ida L Fremont county. Woods; frequent. S. ulmifolia Muhl. Taylor county. Woods; frequent. S. missouriensis Ait. Ringgold, Page, Fremont, Decatur, and Johnson counties. Upland woods; frequent. *S'. serotina Ait. Taylor county. Low places; common. Boltonia asteroides L'Her. Ringgold and Taylor counties. Wet soil; frequent. Aster sericeus Vent. Ringgold, Taylor, Page, Fremont, Mont- gomery, and Pottawattamie counties. Prairies; common. A. multifloniH Ait. Ringgold and Taylor counties. Way- sides; frequent. A. Icevis L. Johnson county. Erigeron strigosus Muhl. Clarke county. Fields; common. E.divaricatus Mx. Ringgold and Fremont counties. Pastures; common. E. canadensis Ij. Page and Fremont counties. Waste places; common. E. annuus Pers. Union and Pottawattamie counties. Waste places; common SilphiiDii perfoliatum L. Ringgold, Taylor, Page, Fremont, Montgomery, and Pottawattamie counties. Low places; fre- quent. S. integrifolium Mx. Ringgold, Taylor, Page, Fremont, Montgomery, and Pottawattamie counties. Prairies; common. S. laciniatum L. Clarke, Union, Adams, Fremont, Mont- gomery, and Pottawattamie counties. Prairies; common. Parthenium integrifolium L. Ringgold county. Prairies; common. Iva xanthiifolia Nutt. Fremont county. River bottoms; common. Ambrosia artemisicefolia L. Clarke, Union, Adams, Montgom- ery, Pottawattamie, Ringgold, Taylor, Page, and Fremont counties. Waste places; common. 188 IOWA ACADEMY OF SCIENCES. A. trlfida L. Clarke, Union, Adams, Montgomery, Potta- wattamie, Ringgold, Taylor, Page, and Fremont counties. Waste places; common. A. pfiilostacluia DC. Fremont county. Waste places: common. Xanthunn canadense Mill. Ringgold, Fremont, and Potta wattamie counties. Waste places; common. Heliopsis IcevU Pers. Decatur and Fremont counties. Upland woods; infrequent. H. scabra Dunal. Taylor, Page, Fremont, and Montgomery counties. Prairies; common. Echinacei anr/iifififolia DC. Clarke, Adams, Montgomery, Pottawattamie, Ringgold, and Fremont counties. Prairies; frequent. Emlbeckia triloba L. Ringgold county. Woods; common. E. laciniata L. Ringgold county. Low woods; common. i?. subtomentosa Pursh. Johnson county. Prairies; fre- quent. Lepacliys pinnaia T. & G. Ringgold, Taylor, Page, and Fremont counties. Prairies; common. Helianthus annuus L. Union, Pottawattamie, Ringgold, Page, and Fremont counties. Waste places; frequent. H. rigidus Best. Ringgold, Taylor, Page, and Fremont counties. Prairies; frequent. H. grosse-serrafus Mart. Fremont county. Low places; common. H. hirsutus Raf. Ringgold county. Woods; common. Actinomerls squarrosa Nutt. Ringgold, Page, and Fremont counties. Low woods; frequent. Coreojysis pal) nat a 'Nntt. Clarke, Union, Adams, Montgom- ery, Pottawattamie, and Page counties. Prairies; common. C. tripjterin L. Ringgold and Taylor counties. Helenium autumnale L. Taylor and Fremont counties. Dysodia chrysan them aides Lag. Union, Ringgold, Taylor, Page, and Fremont counties. Waste places; common. Anthemis cotnla DC. Clarke, Union, Adams, Montgomery, Pottawattamie, Ringgold, Taylor, and Fremont counties. Waste places; common. Achillea inlllefoliuui L. Clarke, Union, Montgomery, Potta- wattamie, Decatur, and Ringgold counties. Fields and upland woods; common; pink, flowered forms are frequently found in Decatur county, in upland woods. IOWA ACADEMY OF SCIENCES. 189 Artemisia ludovk-iana Nutt. Union, Adams, Montgomery, Pottawattamie, Ringgold, Taylor, Page, and Fremont counties. Waysides and fields; common. A. annua L. Decatur county. Waste places; common in one locality. Cacalia atriplici folia L. Union, Pottawattamie, Ringgold, Taylor, and Fremont counties. Prairies; frequent. G. tuberosa Nutt. Union, Adams, Pottawattamie, Ringgold, and Taylor counties. Prairies; common. Arctium lappa L. Clarke, Adams, Pottawattamie, Ringgold, Taylor, and Fremont counties. Waste places; common. Hieracium lonrjipilum Torr. Taylor county. Prairies; fre- quent. H. scabrum Mx. Ringgold county. Woods; frequent. Prenanthes aspera Mx. Ringgold county. Waysides; fre- quent. Lygodesmia juncea Don. Fremont county. Loess hills; com- mon; this species is spreading eastward and is becoming fre- quent in the cultivated fields. Taraxacum officinale Neber. Clarke, Union, Adams, Mont- gomery, and Ringgold counties. Fields and waste places; common. Lactuca iniegrifolia Bigel. Decatur, Ringgold, and Taylor counties. Fields and waysides; frequent. L. scariola L. Decatur, Taylor, Page, and Fremont counties. Waste places; frequent. L. canadensis L. Ringgold county. Waysides; frequent. L. floridana Gaertn Johnson, Van Buren, and Decatur counties. Fields; frequent. L. pulcliella Bigel. Montgomery, Pottawattamie, and Fre- mont counties. Waste places ; common. LOBELIACE.^. Lobelia syphilitica L. Taylor, Page, and Fremont counties. Moist places; frequent. L. spicata Lam. Union and Adams counties. Fields; common. Campanulace.e. Specularia perfoliata A. DC. Union county. Rare. Campanula americana L Taylor, Page, and Fremont counties. Rich woods; common. 190 IOWA ACADEMY OF SCIENCES. Primulace.e. Steironema ciliatum Raf. Fremont county. Woods; frequent. S. lanceolatum Gray. Ringgold county. Frequent in a swampy locality. Apocynace^. Apocynum androsaemlfoHum L. Union county. Waysides and fields; frequent. A. cannabinum L. Clarke, Montgomery, Pottawattamie, Ringgold, and Taylor counties. Fields and waste places; fre- quent. ASCLEPIADACE.-E. Asclepias tKberosa L. Clarke, Union, Montgomery, Ring- gold, Taylor, and Page counties. Fields; common. A. incarnafa L. Ringgold, Page, and Fremont counties. Wet soil; frequent. A. cornutl Decaisne. Clarke, Adams, Pottawattamie, Ring- gold, and Taylor counties. Fields; common; the authority for this species was wrongly given as DC. in the last report. A. suUivantii Englm. Taylor and Page counties. Bottoms; frequent. A. obtusifolia Mx. Union, Adams, and Montgomery counties. Waysides; frequent. A. meadli Torr. Adams county. Prairie; infrequent. A. purjmrascens L. Union and Ringgold counties. Infre- quent. A. verticiUata L. Ringgold, Taylor, Page, Fremont, and Pottawattamie counties. Fields and open woods; common. Acf rates loncji folia Ell. Ringgold and Taylor counties. Prairies; common. A viricUfloi'a Ell. Clarke county. Prairies; frequent. GENTIANACE.E. Gentiana andreicsii Griseb. Decatur county. Prairies; infrequent. (7. alba Muhl. Taylor county. Prairie woods; infrequent. POLEMONIACE.E. Phlox pilosa L. Union, Adams, Montgomery, and Pottawat- tamie counties. Prairies; common. P. divaricata L. Pottawattamie county. Rich woods; common. IOWA ACADEMY OF SCIENCES. 191 Hydrophyllace^e. Ellisia nyctelea L. Union county. Damp localities; com- mon. BORRAGINACE^. Echinospermum virginkum Lehm. Page county. Lithospermvm latifolium Mx. Pottawattamie county. Onosmodium Carolinian iim DC. Union, Adams, Montgomery, and Fremont counties. Pastures; common. CONVOLVULACE^. Convolvulus sepium L. Union, Adams, Montgomery, Potta- wattamie, Ringgold, Taylor, Page, and Fremont counties. Waysides; borders of fields; common. G. arvensis L, Decatur, Taylor, and Fremont counties. Waste places; 'frequent. Cuscufa glomerata Choisy. Taylor county. Low places; frequent. SOLANACE^. Sokmuin nigrum L. Ringgold, Page, and Fremont counties. S. caroUnense L. Taylor and Fremont counties. Waste places; frequent. S. rostratum Dunal. Page and Fremont counties. Waste places; fields; becoming frequent. Physali.s angulata L, Fremont county. A few found. P. philadelpliica Lam. Page and Fremont counties. Fields; frequent. P. lonceolata Mx. Adams and Pottawattamie counties. Open woods; waysides; frequent. Lycium vulgare Dunal. Page county. Waste places; infre- quent. Nicandra physaloides Gaertn. Fremont county. In fields; infrequent. Datura stramonium L. Ringgold, Taylor, Page, Fremont, and Montgomery counties. Waste places; common. D. tatula L. Ringgold county. Waste places; common. SCROPHULARIACE^. Verbasouiit thapsus L. Clarke, Montgomery, Pottawattamie, Ringgold, Taylor, Page, and Fremont counties. Fields; waste places; common. Linaria vulgaris Mill. Clarke and Page counties. Waste places; frequent. 192 IOWA ACADEMY OF SCIENCES. Scrophidaria nodosa marylandica Gray. Ringgold and Taylor counties. Open woods; frequent. Pentstemon grandlfiorus Nutt. Fremont county. Loess hills; frequent. 3Ii)iu(lus ringens L. Ringgold county. Wet places; fre- quent; white flowered forms were found. M. alatus Ait. Decatur county. Wet banks; infrequent. Gratiola virginiana L. Ringgold county. Rich woods; fre- quent. 1/y.santhes riparia Raf. Ringgold county. Wet banks- common. Veronica virginica L. Ringgold and Taylor counties. Prai- ries and woods; common. Seymeria macrophi/lla Nutt. Decatur and Page counties. Upland woods; common. Lentibulariace.e. rtrknlaria iviJgaris L. Fremont county. Frequent in Wabonsie slough. Pedaliace^. 3Iarty nia proboscidea Glox. Taylor county. Waysides; infre- quent. ACANTHACE^E. BuelUa ciliosa Pursh. Clarke, Ringgold, Taylor, and Page counties. Waysides; common. Verbenace.e. Verbena urtica\folia L. Ringgold and Taylor counties. Fields and waste places; common. T: Jia.stata L. Clarke, Union, Pottawattamie, Ringgold, * and Page counties. V. stricta Vent. Ringgold and Fremont counties. T'. bracteosa Mx. Union, Fremont, and Pottawattamie counties. Fields and waste places; common. Lippia lanceoluta Mx. Fremont county. Wet places; fre- quent. Phryma leptostachya L. Page and Fremont counties. Rich woods; frequent. LabiatyE. Teucriuin caiiadense L. Page and Ringgold counties. Low grounds; frequent. Mentha viridis L. Taylor county. Waysides; infrequent. IOWA ACADEMY OF SCIENCES. 193 Lycopus sinuatus Ell. Fremont county. Low ]3laces; fre- quent. Pycnanthemum lanceolatum Pursh. Ringgold county. Way- sides; frequent. F. Unifolium Pursh. Ringgold county. Prairies; frequent. Hecleoma pulegioides Pers. Page and Fremont counties. Woods; common. H. liispida Pursh. Decatur county. Dry, upland woods; common. Monarda Jistulosa L. Ringgold, Taylor, Page, and Fremont counties. Woods; common. M. punctata L. Jefferson county. Lopfiantkus scrophulario'folius Benth. Fremont county. Woods; frequent. L. nepetoides Benth. Ringgold, Page, and Fremont counties. Woods; frequent. Salvia lanceolata Willd. Decatur, Page, and Fremont coun- ties. Waysides; frequent. Nepeta cataria L. Ringgold, Page, Fremont, and Pottawat- tamie counties. Waste places; common. N. glechoma Benth. Clarke and Page counties. Waste places, frequent. Scutellaria versicolor Nutt. Decatur county. Rich woods; frequent. S. parvula Mx. Ringgold county. Prairies; frequent. Brunella vulgaris L. Union, Pottawattamie, Ringgold, Page, and Fremont counties. Open woods; common. Physostegia virginiana Benth. Fremont county. Wet, low soil; infrequent. Leonurus cardiaca L. Decatur and Fremont counties. Waste places; frequent. Marriibium vulgare L. Fremont county. Waysides; scarce. Stachys palustris L. Union and Montgomery counties. Wet soil; common. S. aspera Mx. Ringgold county. Low places; frequent. Phytolaccace^. Phytolacca decandra L. Fremont county. Waysides; infre- quent. Plantaginace^. Plantago rugelii Dec. Ringgold county. Low woods; common. 13 194 IOWA ACADEMY OP SCIENCES. P. aristata Mx. Ringgold, Montgomery, and Pottawattamie counties. Wayside and waste places; frequent. Nyctaginace^. Oxyhaphus nyctagineus Sweet. Union county. Waste places; frequent. 0. hirsutus Sweet. Taylor county. Waysides; infrequent. 0. angustifolius Sweet. Page, Taylor, and Fremont counties. Prairies; infrequent. 0. albidus Choisy. Union county. Waysides; infrequent; the same as AlUonia albida Walt. Illecebrace^. Any cilia capilalcea DC. Ringgold, Page, Fremont, and Pot- tawattamie counties. Woods; frequent. Amarantace^. Amarantus retroflexus L. Page and Fremont counties. Waste places; common. A. albus L. Page county. Waste places. A. blitoides Watson. Fremont county. Waste places. Chenopodiace^. Chenopodium hybridum L. Ringgold and Fremont counties. Waste places; frequent. Cycloloi iia platyjjhyUum Moq. Fremont county. Sandy soil; frequent. Atriplex patulum hastatum Gray. Taylor county. Waste places; infrequent. POLYGONACE^. Bumex crisjnis L. Clarke county. Waste places; frequent. It. acetosella L. Pottawattamie county. Waste places; fre- quent. Polygonum virginianum L. Ringgold and Page counties. Rich woods; common. P. aviculare L. Ringgold, Fremont, and Pottawattamie counties. Waste places; common. P. erectum L. Clarke and Union counties. Waste places; common. P. convolvulus L. Decatur county. Waste places; fre- quent. P. muJilenbergii Watson. Ringgold and Fremont counties. Wet places; frequent. IOWA ACADEMY OF SCIENCES. 195 Fafjopyrum esculentiuii Moench. Page and Pottawattamie counties. Waste places; frequent. F. tataricum (L.) Gaertn. Decatur county. Waste places; one specimen found. Aristolochiace.e. Asarum reflexum ambiguum Bicknell. Decatur, Appanoose, Ringgold and Page counties. Rich woods; common. A. acuminatum (Ashe) Bicknell. Johnson county. Rich woods; frequent. This and the preceding species have hereto- fore been confused with asarum canadense L. Santalace^. Commandra nmbellata Nutt. Page county. EUPHORBIACE^E. Euphorhia serpens H. B. K. Fremont county. E. maculata L. Ringgold and Fremont counties. Waste places; common. E. preslii Guss. Ringgold, Page, and Fremont counties. Waste places; common. E. marginata Pursh. Fremont county. Fields and waste places; common. E. corollata L. Ringgold, Taylor, Page, Fremont, and Pot- tawattamie counties. Fields; common. E. heterophylla L. Decatur county. Bluffs; infrequent. E. cyparissias L. Decatur and Pottawattamie counties. Waste places; infrequent. Acalyplia virginica L. Page and Fremont counties. Fields and waste places; common. Urticace.e. Ulmus fxilva Mx. Union, Pottawattamie, Ringgold, Taylor, Page, and Fremont counties. Woods; frequent. U. racemosa Thomas. Decatur county. An infrequent tree along Grand river. U. americana L. Union, Adams, Montgomery, Pottawat- tamie, Ringgold, Taylor, Page, and Fremont counties. Low woods; common. Celtis occidentalls L. Union, Montgomery, Pottawattamie, Ringgold, Page, and Fremont counties. Low woods; fre- quent. Cannabis sativa L. Clarke, Union, Adams, Montgomery, Pottawattamie, Ringgold, Taylor, Page, and Fremont counties. Waste places; common. Humulus lupulus L. Union, Adams, Montgomery, Pottawat- tamie, Ringgold, Taylor and Fremont- counties. Thickets; common. 196 IOWA ACADEMY OF SCIENCES. Morus rubra L. Fremont county. Low woods; frequent. Urtica gracilis Ait. Clarke, Montgomery, Pottawattamie, Page, and Fremont counties. Low grounds; common. Laportea canadensis Gaud. Ringgold and Fremont counties. Moist woods; common. Pilea xmmila Gray. Ringgold and Page counties. Damp woods ; frequent. Parietaria 'pennsylvanica Muhl. Decatur, Union, Page, and Pottawattamie counties. Low woods; frequent. Platanace^. Platanus occidentaUs. Page and Fremont counties. Bottoms; frequent. JUGLANDACE^. Juglans nigra L. Union, Montgomery, Pottawattamie, Ringgold, Page, Taylor, and Fremont counties. Rich woods; common. Garya alba Nutt. Taylor, Page, Pottawattamie, and Fre- mont counties. Upland woods; common. C. amara Nutt. Ringgold, Taylor, Page, Fremont, Mont- gomery, and Pottawattamie counties. Rich woods; common, CUPULIFER^. Betula nigra L. Ringgold county. Corylus americana Walt. Clarke, Adams, Montgomery, Pot- tawattamie, Ringgold, and Page counties. Thickets; common. Ostrya virginica Willd. Union and Fremont counties. Bluffs; frequent. Quercus alba L. Union and Ringgold counties. Woods; common. Q. macrocarpa Mx. Union, Adams, Montgomery, Pottawat- tamie, Ringgold, Taylor, Page, and Fremont counties. Woods; common. Q. bicolor Willd. Ringgold county. Low woods; frequent. Q. muhlenbergii Englm. Union, Adams, Montgomery, Ring- gold, and Fremont counties. Upland woods; frequent. Q. rubra L. Union, Montgomery, Pottawattamie, Ringgold, Taylor, Page, and Fremont counties. Woods; frequent. Q. coccinea Wang. Ringgold, Fremont, and Pottawattamie counties. Upland woods; common. Q. imbricaria Mx. Clarke, Union, and Ringgold counties. Upland woods and thickets; common. IOWA ACADEMY OF SCIENCES. 197 Q. marylandica Muench. Decatur county. Uplands; a fre- quent shrub associated with Q. nigra L. Salicace^. Salix nigra Marsh. Decatur, Page, and Fremont counties. Along streams; common. S. long if alia Muhl. Ringgold, Taylor, Page, and Fremont counties. Rich soil; frequent. S. humilis MsbYsh. Taylor county. Dry uplands; frequent. S. amygclaloides Anders. Page and Fremont counties. Rich low lands; common. *S'. cordata Muhl. Page and Fremont counties. Low lands; common. -S'. alba vitellina Koch. Decatur county. Becoming fre- quent. Popuhis tremuloides Mx. Union and Ringgold counties. Thickets; frequent. P. monilifera Ait. Clarke, Union, Adams, Montgomery, Ringgold, Taylor, Fremont, Lucas, and Monroe counties. Low lands; frequent. Conifers. Juniperus virginiana L. Decatur county. A small shrub found in upland woods. Orchidace^. Sjnranthes cernua Richard. Johnson county, several speci- mens found in moist places; Decatur county, a single specimen found in prairie upland. S. gracilis Bigelow. Decatur county. About forty speci- mens found in upland prairie grass. Gypripedium parviflorum Salisb. Decatur county. Rich woods; associated with C. pubescens Willd., but much less fre- quent. C. pubescens Willd. Ringgold county. Rich uplands; fre- quent. C. spectabi'e Swartz. Jefferson county. Swampy soil; rare. Specimens were transplanted with with good results. Iridace^. Iris versicolor L. Union, Ringgold, and Page counties. Swamps; ponds; frequent. Belaiiicanda chinensis Adans. Ringgold, Taylor, and Page counties. Waysides; waste places; becoming frequent. 198 IOWA ACADEMY OF SCIENCES. DlOSCOREACE^. Dioscoreavillosa Li. Union and Ringgold counties. Thickets; frequent. LlLIACE^. Smila X herbacea 1j. Union county. Thickets; rich soil; fre- quent. S. hisplda Muhl. Adams, Ringgold, and Fremont counties. Woods; frequent. Allium canadense Kalm. Union county. Fields and woods; frequent. Yucca angustifolia Pursh. Fremont county. Loess hills; common. Polygonatum giganteum Dietrich. Ringgold, Page, and Pot- tawattamie counties. Woods; frequent. Asparagus officinalis. Page, Fremont, and Montgomery counties. Waste places; frequent. Smilacina racemosa Desf. Union county. Woods; frequent. Erythronium mesochoreum Knerr. Decatur county. High prairies; common; blooming before E. albidum Nutt., and the specimens all flowering ones; the leaves very narrow; found also in Harrison county, Missouri. Lilium philadelphicum L. Union and Adams counties. Prai- ries; common. L. canadense L. Montgomery county. Prairies; frequent. L. tigrinum Ker. Fremont county. An escape into waste places. Trillium nivale Riddell. Decatur county. Rocky woods; frequent locally. Melantlmim virglnicum, L/. Union and Adams counties. Damp prairies; frequent. Zygadenus elegans Pursh. Decatur county. Rich woods; frequent locally. PONTEDERIACE.E. Pontederiacordata L. Ringgold county. Margins of ponds; frequent. COMMELINACE^. Tradescantia virginica L. Clarke, Union, and Ringgold counties. Prairies and fields; common. JUNCACEiE. Juncus tenuis Willd. Union and Pottawattamie counties. Grassy places; common. IOWA ACADEMY OF SCIENCES. ]99 J. torreyi Coville. Fremont county. Damp soil; frequent. Typhace^. Typha latifolia L. Union, Adams, Page, and Fremont covm- ties. Margins of ponds; frequent. Sparganium eurycarpum 'EnglvQ.. Ringgold county. Ponds; frequent. S. anclrocladum(Englm..)Morong. Ringgold county. Ponds; frequent. Arace^. Ariscema triphyllum Tor. Pottawattamie county. Rich woods; common. A. dracontium Schoot. Union, Page, and Pottawattamie counties. Rich woods; frequent. LemnaceyE. Spirodela polijrrJiiza Schleid. Fremont county. Ponds and sloughs; common. Lemna trisulca L. Fremont county. Ponds and sloughs; frequent. L. minor L. Decatur, Taylor, and Page counties. Ponds and streams; frequent. Alismace^. Allsma plantago L. Ringgold county. Moist places; fre- quent. Saglttaria variabilis Engl. Ringgold and Taylor counties. Ponds; common. S. graininea Mx. Fremont county. Common in mud flats or shallow water. Naiadace^. Potamogeton fluitans Roth. Common in Wabonsie slough. Cyperace^. Cyperus speciosus Vahl. Ringgold county. C. escidentus L. Montgomery and Fremont counties. Eleocharis ovata R. Br. Ringgold county. E. acicularis R. Br. Fremont county. Margins of ponds; common. Scirpus lacustris L. Fremont county. Ponds; common. *S'. fluviatilis Gray. Decatur county. Frequent in one locality. 200 IOWA ACADEMY OF SCIENCES. S. atrovirens Muhl. Montgomery county. Carex lupidina Muhl. Page county. C. vulpinoidea Mx. Union, Adams, and Montgomery coun- ties. Moist soil; common. G. rosea Schkur. Pottawattamie county. C. cephalophora Muhl. Pottawattamie county. C. cristatella Britton. Adams county. Gramine^. Spartina cynosuroides Willd. Ringgold, Page, Taylor, and Fremont counties. Wet soil; common. Panicum sanguinale L. Page and Fremont counties. Fields and waste places; common. P. virgatum L. Taylor county. Low prairies; frequent. P. glabruin Gaud. Decatur county. P. lanvginosum Ell. Union county. Waysides; frequent. P. macrocarjxm Le Conte. Union county. Woods; fre- quent. P. crvs-galli L. Ringgold, Page, and Fremont counties. Waste places; common. Setaria glauca Beauv. Ringgold, Page, and Fremont coun- ties. Waste places; common. S. viridis Beauv. Page, Pottawattamie, and Fremont coun- ties. With the preceding. S. italica Kunth. Page county. Waysides; frequent. Cenchrus tribuloides L. Fremont county. Sandy shores; common. Zizania aquatica L. Ringgold and Page counties. Ponds; infrequent. Tripsacum dactyloides L. Adams, Ringgold, and Taylor counties. Wet places; frequent. Andropogon scoparius Mx. Decatur county. Uplands and woods; frequent. Crysoj)ogon nutans Benth. Taylor county. Prairies; fre- quent. Phalaris canarlensis L. Decatur county. Waste places; streets; infrequent. Aristida oligantha Mx. Taylor county. Dry soil; frequent. Stipo- spartea Trin. Union, Adams, and Montgomery coun- ties. Prairies; frequent. Muhlenbergia mexicana Trin. Decatur county. Low places; common. IOWA ACADEMY OF SCIENCES. 201 M. soboUfera (Muhl.) Frin. Decatur and Fremont counties. Infrequent. Phleum pratense L. Clarke, Union, Adams, Montgomery, Pottawattamie, Ringgold, Taylor, Page, and Fremont coun- ties. Fields and waysides; common. Alopecurus geniculatus L. Ringgold county. Wet places; frequent. Bouteloua hirsuta Lag. Fremont county. Loess hills; com- mon. B. racemosa Lag. Ringgold, Taylor, Page, and Fremont counties. Waysides; frequent Eragrostis major Host. Ringgold, Page, and Fremont coun- ties. Waste places; common. E. purshil Schrader. Fremont county. Melica mutica Walt. Union county. Woods; infrequent. Dactylis glomemta L. Page county. Glyceria nervata Trin. Union and Adams county. Low prairies; common. Bromus secalinus L. Adams county. Fields; frequent. Bromus ciliatus purgans Gray. Pottawattamie county. Agrovyruiii spicatuiii R. & S. Montgomery and Taylor coun- ties. Prairies; infrequent. Hordeum jubatum L. Clarke, Union, Adams, and Montgom- ery counties. Waste places; common. E. pusillum Nutt. Adams, Montgomery, and Pottawattamie counties. Waste places; waysides; becoming frequent. Elyiiius striatus Willd. Decatur, Pottawattamie, Page, and Fremont counties. Woods; frequent. E. virginicus L. Ringgold county. E. canadensis L, Ringgold, Taylor, and Fremont counties Waysides; frequent. Asprella hystrix Willd. Decatur, Ringgold, Page, and Potta- wattamie counties. Woods; frequent. Equisetace.e. Equisetum arvense L. Union and Fremont counties. Moist soil; common. E. kevigatum Braun. Adams, Union, Montgomery, and Pot- tawattamie counties. Uplands; waysides; frequent. FiLICES. Adiantum pedatum L. Ringgold, Page, and Fremont coun- ties. Rich woods; common. 202 IOWA ACADEMY OF SCIENCES. C/jstopteris fragilis Bernh. Union, Page, Pottawattamie, and Fremont counties. Rich woods; common. Onoclea strutMopteris HofCm. Decatur county. Rich woods; infrequent. Ophioglossace.e. Botrychium virginianuni Swartz. Pottawattamie county. Rich woods; frequent. EXTENSION OF COMPLEX ALGEBRA TO THREE- FOLD SPACE. BY T. PROCTOR HALL. Taking rectangular coordinates in a plane, let x, y, be unit vectors along the axes of X, Y, respectively; and let A be any unit vector from O in the plane, making an angle a with X. Let i be a rotor such that i^ rotates any vector, A, through n. 90° in the positive direction. Then i x=y. f A= —A . • . f = —1. Equating vectors from O : A=xcos a -\- y sin a. = (cos a + i sin a) x. =e** X, (by expansion in series). A vector (A) is here considered to be composed of three dis- tinct components or factors; a unit direction (.»), a length (which, for the sake of simplicity, is here considered unity), and a rotor (cos a-{- i sin a, or e^") which has rotated the vector from unit position {x) to any other position (A) in the plane. The product of two vectors is Aj Ag = (cos ttj + i sin a^) (cos a^ + * sin aj ^•^• = [cos (flj + a^) + i sin {a^ + a,)] x. = 6 ^ ^^1 + S^ X. Since x is unity in every one of its capacities, x x = x, as given above. The unit vector, x, is a factor of every term of this algebra, and may be dropped, leaving an algebra of rotors only, which IOWA ACADEMY OF SCIENCES. 203 has the laws of operation of ordinary algebra, and which com- bines with it to form an algebra of tensors and rotors — the ordinary complex algebra. The kinds of number involved in this algebra are : (1) reals, a, b, c, (2) plane imaginaries, fa, ib, (3) the plane complex, z = a+i b. Next let the a-^z-plane be the equatorial plane of a sphere of which Z is the pole. Let the power of the rotor / be extended so as to rotate any vector, whether in the ;r?/- plane or not, about the 3-axis. Let./ be a new rotor, such that./'" rotates any vector through m. 90'^ in a direction from the plane of x, y, toward the pole z. By means of these two rotors i°, ./'", a vector may be turned from the unit position {x) to any other position (A); and the order of the rotations is indifferent. j 1° x=i°^j x=J x=-z. f A= —A . • . /== -1. It follows that ,/'" may be expressed in the forms cos b + j sin &, and e^ ^. Any unit vector, A, is therefore of the form A= (cos a -\- i sin a) (cos b + ./ sin b) x = Qia+Jb ^^ Prom either of these forms the product or the quotient of two vectors is evident. Dropping x, as before, and introducing tensors w^e obtain a tensor-rotor algebra which, when the l and j binary factors are kept separate, has the laws of operation of common algebra, and has many of the advantages of a vector algebra without its limitations. The most general quantity in this algebra is the double complex (a+i b) (c+,/ d), in which a, b, c, d, are connected by one relation. The double complex may be expressed in the form which is identical with a+i b+./ c. But unfortunately in the latter form it does not obey the laws of common algebra, except in addition, subtraction, and multiplication by reals. 204 IOWA ACADEMY OF SCIENCES. The double complex a+i b+./ c is related to points in three-fold space in the same way that the plane complex a+i b is related to points in a plane, and in the form or in the general forms (a+i b) (c+J d), e^ + ^'^ + J^, it may be treated as an ordinary algebraic quantity. Kansas City University. A REVIEW OF THE CERCOPID^E OF NORTH AMER- ICA NORTH OF MEXICO. BY E. D. BALL,.' The family cercopidse, though of world-wide distribution, has comparatively few representatives within our borders, and those few have been but imperfectly known, the literature on the subject being scattered and fragmentary, the generic references often incorrect, and the specific determinations, owing to the extreme variability in color of some species, and the striking similarity of color between others, rendered very questionable. Scarcely one of the more common forms but what has been referred to under at least four different genera and several have more than that number of specific names. This paper recognizes twenty species as included within our fauna, of which Say described six, Fitch three, Germar one, Uhler four, two were introduced from Europe, and four are here described as new; besides these there have been twenty more described, which have been referred to the first twenty as synonyms or varieties. Except for the isolated descriptions and a few lists, the first systematic work done on the American species was Uhler's article on the family in the Standard Nat. Hist. (1884). In 1889 Provancher, in his Hemip. du Canada, published the first synopsis of the group; he divided the family into IOWA ACADEMY OF SCIENCES. 205 three genera (omitting the Issidae) which were correctly used except that he included^!/. 4-angularis under Aphrophora: in his recognition of species he was less fortunate, as all three of his species ofTMlcenus were varieties ofspumarius. In 1892 Dr. Goding published a synopsis of the genera, together with a bibliographical and synonymical catalogue of the described species; the characterization of the family was simply a translation of Stal's in Hemip. Africana, and the synopsis of the subfamilies and genera an adaptation from the same work. Under the subfamily Cercopince, he recognized five genera, although Stal himself, the next year after the publica- tion of that synopsis, united four of these genera, and later (Hemip. Mex.), all live; aside from that, however, the only excuse for inserting the fifth genus' (BJiinaulax) was a MS. note by Dr. Fitch, placing the fabrician species^ coccmea there, while A. & Serv., the authors of all five genera, placed it in the ^vsi' {Toniaspis). Under the^AphropJiorince he separated six genera, although of one [Glovia) he made no reference in the catalogue, and of SinoiheiP (Ptyelus), he left only two undeter- mined species of Walker's, one of which was sPpjiilcenus, and the other a^Lepyronia, while the genus Ptyelus, as characterized by him (from Stal), has not been recognized outside of Africa. Fowler, in the Biologia, describes a number of new genera and species of Cercopidse, and has worked out considerable synonomy, of which only the following affects our species: ^ T. fasciaticoUis St3b\=simulans Walk, and Mcincta Saj=^rubra Linn. The first appears to be correct; the second is not, as can be readily seen by comparing' Mcincta with his figures, when it will be seen that it equals .si//m/arj.s and not "rubra, and, beifig the first described, take^precedence. He also described a number of new species of Clastoptera without recognizing xanthocephala,^proteus or^cklicata, specimens of all of which have been examined from Orizaba and other Mexican points, includ- ing several varieties, so that no doubt most of his species will fall as synonyms. ^ In 1896 the author published a revision of the^Cflastoptera, which, with the present paper, completes the family. While working on that paperV. lineatus Sknd'^ilineatus were recognized as distinct and attention was called to the generic difference, the venation of each species being figured on the generic plate. 206 IOWA ACADEMY OF SCIENCES. Q In 1897 Baker, in Notes on the genus Phlkenus, recognized the four species, separated the bibliography of lineatus and bilineatus and tried to restrict the latter to the west, while he described the eastern representatives as a distinct species americanus; an examination of a type and other eastern material shows no grounds, however, for the separation. During the prosecution of this work I have been placed under special obligations to Mr. Otto Heideman for the loan of a large series of both eastern and western forms, among them the largest collection of esbsteri/ Clastoptera and of west- ern *^p/irop//ora that I have seen; to Professor Bruner for the loan of Nebraska, California, and Mexican material, and to Professors Piper, Gillette, Lintner, Pernald, Morse, C. M. Weed and H. E. Weed, for examination of material from their respective localities; to Professor Uhler for helpful sugges- tions, and especially to Professor Osborn, under whose super- vision the work was originally planned, for the use of his own, the Iowa Agricultural college and V. D. collections, all of them extensive, and (later) the Ohio material; and to Pro- fessor Summers for the continuation of the same favors. Besides the above, my own collection has furnished me with large series from Iowa, the Pacific coast, the West Indies and Mexico. ^ FAMILY CERCOPID.E A. & S. Body stout, compact; general form oval or elongate: head in nearly same plane as the body; vertex nearly flat, anterior margin rounding or angulate: ocelli, two, placed near the posterior margin; front convex, more er less inflated, transversely ribbed, nearly flat dorsally where it forms a subquadrate insertion in the anterior field of the vertex, from which it is separated by a distinct suture (this portion of the front is considered as part of the vertex and referred to hereafter as the tylus); antenna? short, placed in front of and between the eyes under the margin of the vertex, the two basal joints bead-like, the remainder setaceous, pronotum large, anterior margin straight or angularly rounded, posterior margin short, often deeply emarginate; elytra longer than the abdomen, coriaceous, irregularly reticulated or with two long discoid cells and five or more apical cells; wings with a broad margin beyond the intramarginal vein; posterior coxte and femora short and stout, posterior tibiie scarcely longer than the others, round at the base, spatulate at the apex, armed on the outer margin with two stout spurs, the second twice the length of the first; tibia3 and two basal joints of the tarsi terminated with crescent-shaped rows of spines. The members of this family are readily recognized by the two spurs on the cylindrical hind tibiae. Some Fulgoridse IOWA ACADEMY OF SCIENCES. 207 have similar spurs, but the tibias are in that case angulate and the antennae are below instead of between the eyes. All of the N. A. representatives fall in the first two subfamilies of Stal, which may be separated as follows: ^^ SYNOPSIS OF THE SUBFAMILIES. A. Anterior margin of the pronotum straight; head narrower than pronotum; ocelli placed close together; eyes small, rounded; elytra broad, irregularly rounded at apex. Cercoinnce Stal. O AA. Anterior margin of pronotum angulate or rounded; ocelli farther apart, eyes oblong or angulate; head equalling, or almost equalling, the pronotum in width; elytra compressed behind, rarely reticulate AphrophorincK Stal. '^ SUBFAMILY CERCOPIN^. This subfamily includes large, showy forms in black, red and yellow and is well represented in the tropics. The N. A. forms all belong to a single genus and only a single species occurs north of the Mexican border, and it is more abundant farther south. v"" GENUS TOMASPIS A, & S. Tomaspis A. & S. His. des Hemip. p. 561, 1843 - Triecphora A. & S. His. des. Hemip. p. 561, 1843. 0 Monecphora A. & S. His. des. Hemip. p. 562, 1843. : Sphenorhina A. & S. His. des. Hemip. p. 562, 1843. Head small, much narrower than the humeral angles of the pronotum: front strongly inflated, anteriorly produced, usually beyond the vertex to which it rounds back, transversely ribbed and usually medially carinate; rostrum short, two jointed, scarcely reaching the middle coxa?; vertex much shorter than the pronotum, obtusely angulate, tylus large, eyes small, nearly round; ocelli twice farther from eyes than from each other; pronotum large, anterior margin straight, lateral margins long and strongly oblique, posterior margin straight or emarginate; elytra coriace- ous, somewhat flaring, wider than the pronotum, apex rounding equally from both sides, venation obscure, apically reticulate; wings with the intramarginal vein entire, third longitudinal vein forked. ^ TOMASPIS BICINCTA Say. OCercopis bicincta Say. Jour. Acad. Nat. Sci. Phil. VI, 303, 1831. C Cercopis ignipecta Harr. (MSS.) Cat. Ins. Mass. 1833. OMomcphora bifascia Walk. List Hom. B. M. p. 679, 1851. C Monecphora angusta Walk. List Hom. B. M. p. 680, 1851. £ Monecphora neglecta Walk. List Hom. B. M. p. 683, 1851. <^ Monecphora ignipecta Fitch. (Descrip.) 3d Rep. Ins. N. Y. p. 71, 1856. O Monecphora inferans Walk. List Hom. B. M, Sup. p. 176, 1858. O Sphenorhina simulans Walk. List Hom. B. M. Sup. p. 183, 1858. <) Tomaspis fasciaticollis Stal. Stett. Ent. Zeit. XXV, p. 63, 1864. 6 Tomaspis rubra Fowler. Biol. Cent. Amer., p. 183 (in part). J Tomaspis simulans Fowler. Biol. Cent. Amer. p. 185 208 IOWA ACADEMY OF SCIENCES. Broadly oval, with a narrow, angulate head; deep brown to black with the margins of the vertex, a transverse band across the middle of the pro- notum and two across the elytra, red or orange, length 8-10 mm.; width on elytra 0 mm.; vertex broad, depressed two-thirds the length of thepronotum, obtusely angulate, disc sloping, depressed either side the longitudinal carina; front inflated, nearly right angled with the vertex, a single strong median carina; rostrum short, scarcely as long as the front; pronotum, disc convex, one-third wider than long, anterior margin straight, posterior margin roundingly emarginate; elytra convex, coriaceous, over twice longer than wide, much broader than pronotum, outer margins curved, apex broadly rounding; venation obscure, apically reticulate. Color, dark-chestnut brown to black; a narrow margin all round the vertex and along the median carina, the eyps and ocelli and the lateral margins of the pronotum red; a narrow transverse band across the humeral angles of the pronotum and two slightly wider ones parallel with this, dividing the elytra into three equal portions, red or orange. Habitat: Specimens are at handfrom New York, Massachu- setts, Connecticut, Maryland, District of Columbia, North Caro- lina West Virginia, Florida, Louisiana, Texas, Kansas, and Iowa within our territory, and from Cuba and Mexico from without. It has been reported from Pennsylvania, Askansas, and Georgia, and from Mexico, Jamaica, and several Central American states. It is a very common species in collections from Mexico and the West Indies. In the United States it occurs along the Atlantic slope from New York and Massachu- setts south, throughout the gulf states and up the Mississippi valley as far as central Iowa, where it is extremely rare. This is a somewhat variable species in size, and extremely so in color markings. These forms intergrade and can only be roughly divided as follows: O Form hicincta, the typical one, is dark brown with narrow, red bands. O Var. ignipecta Fitch, is the dark form where the bands are partly or entirely wanting. C Var. simulans Walk., has the bands broader, and creamy yellow in color. Fowler was evidently misled in placing this species, by Say's remark thatr 6icmcia resembled rubra Sbud^'sororia. It is very likely that those were the only two species that Say was acquainted with, or, at least, the nearest to his species of any that he knew; at any rate, the difference in the front, as shown by Fowler's figures, at once places it with' simulans and not with'rubra, and verifies Stal's observation that /ascia^icoZZis was "close" to^ hicincta. Walker says of^ m/er«?i.s that it closely resembles, and may be a local variety of neglecta. 0 IOWA ACADEMY OF SCIENCES. 209 Fowler places it as a synonym of bifascia, along with angusta. The latter was described, from Georgia and is an undoubted, synonym of ^bicincta, and. if Fowler is correct in uniting the three forms, as it seems, then all four species fall as synonyms of bicincta. " SUBFAMILY APHROPHORIN^ Stal. In this subfamily the species are smaller, more elongate, and, as a rule, rather somber colored. The group is well represented in our territory in both genera and species. Two of the species are European and probably introduced, while many of them are widely distributed, and several extend . beyond our borders to the southward. SYNOPSIS OF THE GENERA. A. Apex of clavus acute, cQrium without a terminal membrane. B. Anterior margin of the pronotum angulate, ocelli nearer each other than eyes; rostrum long; exceeding the hind coxa?, with three visible segments, the terminal one much the longest. . Aphrophora Germ. BB. Anterior margin of pronotum rounded, ocelli nearly equally dis- tant from eyes and each other: rostrum short, not exceeding middle coxae; composed of two equal visible segments. C. Anterior margin of vertex between front and eyes sharp; whole upper surface densely pubescent, almost hiding sculpturing and venation: submarginal vein of wing interrupted between second and third sectors. Lepyronia A. & S.C' CC. Anterior margin of vertex between front and eyes sulcate. D. Elytra irregularly reticuled apically. Philaronia n. g.O DD. Elytra with about five apical cells. Phikenus Stal.^? A A. Apex of clavus broadly rounded, corium with a broad terminal membrane; submarginal vein of wing interrupted at apex. (Small globose forms. ) *Clastoptera Germ . !> GENUS APHROPHORA Germ. Vertex obtuse or rectangulate, the apex rounding, anterior margin between the eyes and tylus sharp, ocelli placed close to the posterior margin, nearly twice farther from the eyes than from each other; head with the eyes scarcely as wide as the posterior angles of the pronotum, the anterior and posterior margins nearly parallel, the latter with a median triangular notch between the ocelli, into which fits a slight projection of the pronotum; front convex, inflated, transversely wrinkled except on the median line; rostrum long, with three visible segments, the last one much the longest, extending beyond the hind coxae; pronotum large, about one- half longer than;the vertex, anterior margin distinctly angulate, medially produced into the notched vertex; a distinct median carina extending *For a'synopsis of the Clastoptera see la. Acad, Sci, Proc. Vol. Ill, p. 182. 14 210 IOWA ACADEMY OF SCIENCES. across both vertex and pronotum: elytra coriaceous, about twice longer than wide, without an appendix, the apex rounding, both veins of corium forking before the middle, forming two long discoid cells: apical cells irregular, usually about five; wings with the third vein from the marginal vein forked and forming a closed apical cell; entire dorsal aspect of insect coarsely and irregularly punctate: male valve wanting. The members of this genus are all of moderate size, varying from 8 to 12mm. in length, and are strikingly uniform in color and pattern of marking, being grayish or brownish, with two irregular, oblique, dark-margined light bands on the elytra, sometimes obscure and sometimes broken up into spots. The variation in color and marking is not sufficient to enable one to readily recognize the different species and they are only accurately separated by reference to structural char- acters, the three most important being the degree of inflation of the front with the corresponding variation of the facial angle, the shape of the terminal ventral segment of the male abdomen and the shape of the male plates, the latter character alone enabling one to readily separate that sex of all our species. In distribution this genus seems to be limited to the north- ern hemisphere, and the greater number, if not all the species, occur in the temperate zone. Europe has three species, all of which are widely distributed, while this paper recognizes eight species occurring in the United States and Canada, and Fowler has recently described three new species from Mexico in the Biologia. These latter are all small and are apparently closely related to 4-notata, the only one of our species that has been taken as far south as our southern border. Of the species under consideration 4-notata has the greatest known range, occurring from Ontario to Florida, and west to North Dakota and Iowa. Next to it com.es' per mutata, which has been found from Vancouver's island south to central Calif ornia and eastward to Colorado. Of the others, parallela^^ is the only one that has as yet been recorded from widely separated localities, and it is very probable that some of its western records were based on other species. SYNOPSIS or THE SPECIES. A. Elytra very broad, angulate behind, the outer margin strongly curved and with two more or less distinct hyaline areas; general color light-gray or brown; head and pronotum nearly flat, front but slightly inflated, acutely angulate with vertex. IOWA ACADEMY OF SCIENCES. 211 B. Hyaline areas distinct, outer discoid cell its own width from margin. 4-notata Say. ^ BB. Hyaline areas indistinct, outer discoid cell not more than half its width from costal margin. angulata n. sp. ^ AA. Elytra elongate, rounding behind, the outer margin broadly curved, without trace of hyaline costal areas: usually with front inflated and the pronotum elevated. B. Front inflated and produced, meeting the vertex in nearly a right angle; elytra strongly convex, species large, dark. C. Front much produced, extending distinctly beyond the tylus, to which it rounds back; ovipositor long. parallela Say. '^ CO. Front not extending beyond the vertex, pygofers and ovi- positor short, the latter scarcely exserted. D. Front meeting the vertex at a right angle; plates attin- gent, finger-like. permutata Uhl. ^ DD. Front meeting vertex at a slightly acute angle: plates broad and stiort, divergent. irrorata n. sp. O BB. Front moderately flat, meeting the vertex at an acute angle; species smaller, narrower, lighter colored. C. A broad, white median stripe on vertex and pronotum; face and vertex making an angle of about 50 degrees: pygofers long, narrow, ovipositor exserted; plates short, consisting of two rounding lobes saratogensis Fh.o CC. At most a narrow, light stripe on vertex, not extending on to pronotum, face and vertex making an angle greater than 50 degrees; pygofers short, ovipositor scarcely longer: plates acute, divergent. D. Pronotum and elytra strongly maculate, plates divergent from base, suddenly narrowed before the apex. annulata n. sp. ^ DD. Pronotum and elytra nearly unicolorous; plates attingent at base, divergent before the apex, regularly narrow- ing signoretii Fh. '^ APHROPHORA QUADRINOTATA Say. A. quadrinotata Say. Jour. Acad. Nat. Sci. Phil. VII, p. 304, 1831. Dark grayish -brown, with two large hyaline areas on the costal margin of each elytron; closely resembling the European-^, aim in color and marking, but much smaller and with a longer vertex; length 7-8mm., *width 3-3. 5mm. Vertex nearly flat, one-half longer on middle than at eye, anterior margin rounding, the edge sharp, posterior margin broadly angulate with a distinct notch, median carina distinct; front scarcely inflated, the infla- tion being about half the length of the long diameter of the eye, forming an acute angle with the vertex; pronotum rather flat, median carina sharp; elytra broad, the costal margin flaring before the middle; whole upper surface of insect coarsely and irregularly punctate. •^Width is always given across the widest part of the elytra when folded. 212 IOWA ACADEMY OF SCIENCES. Color: Vertex, grayish-brown, anterior margin of tylus black-lined, rest of margin light, except against the dark eyes; ocelli red; median carina light: pronotum grayish, the carina and a spot on either side before the middle pale: elytra with the claval areas pale, grayish, corium darker, an oblique hyaline band before the middle, extending from the costal margin to the inner sector, sharply margined behind, fading out in front, behind the middle is an elongate hyaline spot: between these spots is an irregular, dark-brown area, and in well marked specimens another appears in front of the band and a third behind the spot. Genitalia: Female pygofers about one-third longer than wide, slightly exceeded by the ovipositor; two last segments of the male abdomen elongate narrowed; plates small, twice longer than wide, separated at the base by their own width, their inner margins parallel, outer rounding. This is the most abundant of the eastern species and is readily recognized by its small size and white markings. A series of several hundred examples show little variation in size or color. Habitat: Examples have been examined from Ontario, New York, New Hampshire, District of Columbia, Maryland, West Virginia, Georgia, Florida, Iowa and Nebraska, and it has been reported from Ontario, Maine, Massachusetts, Ohio, Illinois, and North Dakota. O APHROPHORA ANGULATA n. sp. A. angulata Uhl. Mss. Pale, nearly uniform grayish-brown, two obscure hyaline spots along the costa; larger and more obscurely marked than o ^-notata; length 10mm., width -Imm. Vertex flat, scarcely longer on middle than next to eye, anterior margin sharp as far as the tylus, which is slightly produced upon the front: median carina weak on the tylus, becoming strong on the posterior margin of the vertex; front weakly inflated, forming an acute angle with the vertex as in Jf-notata; pronotum, anterior third depressed, finely punctate, with a sti'ong median carina, behind this, elevated and coarsely pitted, with the carina weak; elytra very broad in the center, roundingly angulate behind; the costal area attaining the center of the corium at the angle of the first sector. Color: Grayish-brown; vertex and anterior third of pronotum brown, with the fine punctures black, median carina light, rest of pronotum light, with dark pitting: scutellum light-gray; elytra, ground color light, coarsely pitted with brown, becoming darker on the middle of the costa, either side of which there is a large subhyaline area, nervures mostly dark margined and distinct. Genitalia: Female pygofers scarcely half longer than wide, moderately exceeded by the short ovipositor. IOWA ACADEMY OF SCIENCES. 213 Described from a single female labeled "Cal.," received from Professor Bruner. Other examples have been examined, one of which bore Uhler's MSS. name as above. This species is similar in structure and color to" Jf-notata, but readily separated by its shorter vertex, larger size and more uniform coloring. ^ APHROPHORA PARALLELA Say. O Cercopis paralkla Say. Narr. Long's Expid. II, 304, 1824. O Ptyelus cribratus Walk. Homop. B. M. 712, 20 (fide Fitch). Dusky reddish-brown, with two narrow, oblique, light bands on the elytra; body broad and deep, vertex long and the front much inflated; length 9-lOmm., width 4-4.25mm. Vertex, flat or slightly transvei'sely depressed behind the tylus, fully one-half longer on middle than at eye, anterior margin thick, nearly straight to the tylus, tylus produced and rounded in front, its length equaling two-thirds of its width; front strongly inflated and pi'oduced, extending slightly beyond the vertex, its greatest inflation being nearly one-half greater than the long diameter of the eye: pronotum depressed on the anterior half, suddenly elevated and rounded on the posterior portion, the lateral margins long and sharply earinate, exceeding in length the dis- tance between the ocelli; elytra broad and convex, narrowing behind; costal area very broad, but not reaching the center of the corium. Color: Tawny, punctured with dark-brown; vertex, reddish-brown, finely punctured, the anterior margin shining black, interrupted on margin of tylus, median carina broadly white behind tylus; pronotum light-gray, heavily punctured with light tawny-brown; elytra grayish, heavily over- cast with tawny, an interrupted light band running from the apex of scutellum to the center of costa and another starting in a spot on the inner margin at the apex of the clavus and running forward to meet the other on the costa: these bands are often reduced to white bars on the nervures, and are usually margined with darker. Genitalia: Female pygofers, long and narrow, exceeded a full milli- meter by the ovipositor; ultimate ventral segment of male short, its length about equaling its basal breadth, narrowing apically, the margins curving up and the lateral angles produced in the forms of style like appendages as long as the plates; plates nearly square, the posterior angles rounded. Habitat: Specimens are at hand from Ontario, New York, Pennsylvania, Vermont, Massachusetts, Maryland, West Virginia, Michigan, and it has been reported from Nova Scotia, Ontario, Michigan, Illinois, Missouri, and Arkansas. The last two references probably refer to some other species, leaving it with a known distribution from Canada south to New Jersey, and west to Michigan and Illinois. 214 IOWA ACADEMY OF SCIENCES. 0 APHROPHORA IRRORATA H. Sp. Dark rusty-brown, flecked with lighter, very closely resemhling per iimtata; longer and narrower thSiWparaUela, with a much shorter vertex and a less swollen front; length ll-12mm., width 3.5-4mm. Vertex short, transversely depressed, only slightly longer on middle than at eye, anterior margin thin, tylus broad and short, nearly twice wider than long, median carina obscure, front moderately inflated, outline a regular curve from clypeus to vertex, angle with vertex acute, inflation of front less than the long diameter of the eye: pronotum transversely depressed before the middle, posterior disc elevated, carina weak except across the depressions, lateral margins short, their length less than the distance between the ocelli; elytra, long and narrow, much exceeding the abdomen, but little windened at center of costa: costal margins scarcely reflexed: costal area narrow, no more than one-half wider at the angle of the first sector than at the discoid cells. ■ Color: Vertex, dark rusty-brown, median carina and a spot either side the tylus, light; anterior half of the i^ronotum light, with few dark punctures except along the carina, posterior half densely punctured darker; elytra tawny, interrupted by numerous small circles of white, often inclosing a single dark puncture, these somewhat irregularly arranged, but usually showing three light areas, separated by two darker ones along the costa; an oblique light band from the center of scutellum to the center of the corium: a light spot before the apex of the clavus and another behind. Genitalia: Female pygofers short and convex, exceeded by the short ovipositor by a distance of less than one-half their width: ultimate ventral segment of male abdomen longer than wide, narrowing behind, convex, shining: plates broad, parallel margined, inner posterior angles excavated, leaving a rounded notch nearly half their depth, outer posterior angles produced, acutely pointed. Described from several examples received from Professor Bruner, taken in Sioux county, Nebraska (War-Bonnet Canon), and others taken in Rist Canon (Ft. Collins), Colo. This species resembles parallela quite closely in color and marking, and was probably the one referred to by Say as occurring in Missouri and Arkansas. It is quite distinct structurally and may be readily separated by the short vertex, longer elytra and the striking differences in front and genitalia. "■ APHROPHORA PERMUTATA Uhl. A. pcrmutata \Jh\. List Hemip. Colo, and N. Mex., p. 472, 1872 (Mss.). A. permutata Uhl. List Hemip. West Miss. Riv., p 345, 187G (Descrip.). A. permutata Uhl. Stand. Nat. Hist., p. 243, 1884 (Distribution). Varying from dark rusty -brown to brownish-yellow, with two oblique dark-margined, light bands on the elytra; resem- bling irrorata, but with a more inflated front, and longer, nar- rower male plates; length 9 -12mm,, width 3.5mm. IOWA ACADEMY OF SCIENCES. 215 Vertex, sloping or transversely depressed, about one-fourth longer on middle than at eye, anterior margin moderately thick, nearly straight to the tylus: tylus moderately produced and rounded, fully twice wider than long: front moderately inflated, the inflation equaling the long diameter of the eye, produced anteriorly, forming a right angle with the vertex; pro- notum somewhat depressed before the middle, disc elevated, the lateral margins about equaling in length the distance between the ocelli: elytra long and narrow, exceeding the abdomen: costal area less than one-half wider at the angle of sector than opposite the discoid cells. Color: Vertex tawny, punctured with darker, carina light; pronotum grayish, coarsely punctate with tawny or rusty-brown; elytra tawny or grayish-brown, coarsely punctate with darker: an oblique, light band from the scutellum to the center of the corium, another from before the apex of clavus, running transversely on to the corium, then obliquely back to the costa, both bands broadly dark margined, the anterior one emphasized on the costa. Genitalia: Female pygofers and ovipositor short and compact, thickly set with coarse hairs: ultimate ventral segment of male abdomen longer than its basal width, narrowing apically; plates in the form of long, taper ing, finger-like processes, attingent until just before the black tip, where they narrow slightly and diverge. Habitat: Specimens are at hand from Vancouver's island, Washington, Oregon, California, Idaho, Montana, and Colo- rado, and Uhler reports it from Utah. - APHROPHORA SARATOGENSIS Fitch. Lepyronia saratoqensis Fitch. Cat. Hom. N. Y., p. 53, 1851. - Ptyelus detritus Walk. List Hom. B. M., p. 713, 1851. ^ Ptyelus gelidus Walk. Hom. B. M., p. 714, 1851. Fulvous or grayish-brown, a broad, median light stripe across head and pronotum, and oblique, light bands on the elytra; smaller than either' para ZZe^a of" permutata , and with a less inflated front; length 3.5-lOmm., width 3-3. 5mm. Vertex, nearly flat, anterior margin thin, confluent with that of the tylus, w^hich is also carinate anteriorly, making the entire anterior margin of the head thin and rounding, parallel with the posterior margin: front small, outline a regular curve, inflation less than the long diameter of the eje: pronotum only slightly convex, transverse depression before the middle very slight, carina weak, except across the depression: elytra moderately long and narrow, slightly exceeding the ovipositor in the female, costal margin scarcely reflexed. Color: Vertex, fulvous with a broad, median light stripe: pronotum fulvous in front, grayish behind the middle, a broad, median light stripe, creamy yellow in front, broader, paler and including a few dark punctures behind the middle: elytra fulvous or grayish-brown, with the oblique, light bands broad and indistinct, rarely margined with darker. Genitalia: Female pygofers half longer than their basal width, exceeded about one millimeter by the ovipositor, which is scarcely 216 IOWA ACADEMY OF SCIENCES. exceeded by the elytra: ultimate ventral segment of the male abdomen very short, nearly four times wider than long, convex, the posterior angles produced, style like: plates subquadrate, rounded behind. Habitat: Specimens are at hand from Ontario, New York, New Hampshire, District of Columbia, Maryland, and West Virginia, and it has been reported from Ontario, and Walker 's species were from Nova Scotia and Florida. Readily separated from paraZZe^a by its shorter vertex and smaller front, as well as its smaller size and lighter color; from signoretii, which it more closely resembles, by the light stripe and the male genitalia. 6 APHROPHORA ANNULATA n. Sp. Light ochraceous-brown, irregularly maculated with chest- nut, lighter colored and more heavily marked thsknsaratogensis, with a shorter female ovipositor and narrower, divergent male plates; length 10-llmm., width 3.5-4mm. Vertex, flat, sloping, strongly angularly emarginate behind, roundingly angulate in front, scarcely longer in the middle than against eyes, anterior margin very thin either side tylus, tylus very broad and short: front moderately inflated, about equaling long diameter of eye, slightly anter- iorly produced, forming very nearly a right angle with the vertex: pro- notum strongly depressed on the anterior half, then suddenly elevated and I'ounded on the disc, the lateral margins short, sharp and oblique, scarcely as long as the distance between the ocelli, elytra moderately long, some- what inflated, the costal margin reflexed anteriorly. Color: Vertex, ochraceous, with a faint, median light line, bordered by two broad chestnut ones; pronotum pale, ochraceous, a chestnut stripe arising just before the middle on either side the carina and running back- ward, and then obliquely outward and broadening to the claval margin; disc of scutellum chestnut, the margins pale, elytra pale, ochra- ceous, an area at the base, an oblique band from the scutellum, broadening to just before the middle of the costa, another before the apex of the clavus and the nerve at the base of the apical cells, deep chestnut. Genitalia: Female pygofers convex, scarcely longer than wide, ovi- positor short and stout; ultimate ventral segment of the male abdomen nearly twice wider than long, subcylindrical; plates broad at the base, the outer margins flaring, inner margin cut off obliquely nearly to the base, slightly sinuate, leaving two widely divergent, black-tipped points. Described from sixteen examples labeled "Wasatch, Utah, 6-27-91, " received through the kindness of Mr. Otto Heide- mann. Easily separated from permutata, which occurs in the same region, by the lighter color and heavier marking, as well as by the very distinct genitalia. IOWA ACADEMY OF SCIENCES. 217 ' APHROPHORA SIGNORETII Fitch. A. signoretii Fitch. Third Report Ins. N. Y., p. 70, 1856. Tawny-brown, varying to pale ochraceous, line on vertex and pronotum and marking of elytra almost obsolete; slightly smaller than saratogeiisis, with a shorter, blunter vertex and stronger front; length 8.5-lOmm., width 3.5mm. Vertex, sloping or depressed, very obtusely angulate, anterior and posterior margins parallel, anterior margin sharp to the tylus, tylus dis- tinct, slightly elevated; front moderately inflated, about equaling the long diameter of the eye, not produced anteriorly, forming an acute angle with the vertex; pronotum rather strongly depressed before the middle, but only slightly elevated behind, leaving it rather flat, side margins distinctly shorter than the distance between the ocelli: elytra moderately long, the costal margin reflexed anteriorly. Color: Vertex, tawny, darkest on the tylus, carina obscurely marked; pronotum tawny-brown, scarcely a trace of gray on the elevated disc, anterior depressed portion lighter, scutellum lighter on the disc: elytra varying from tawny to ochraceous, light bands, not very prominent, the anterior one arising well back of the scutellum and not attaining the costa, the posterior one arising near the apex of clavus and running nearly trans- versely to the costa. Genitalia: Female pygofers convex, moderately long, exceeded by the ovipositor, which does not reach the tips of the elytra: ultimate ventral segment of the male abdomen nearly twice longer than penultimate, one- half longer than its basal width, narrowing apically, disc convex: plates stout, forcep-like, black-tipped, their outer margins rounding, the inner ones obliquely divergent. Habitat: Specimens are at hand from New York and Ontario, Canada. This species has been confused wittPsaratogensis to such an extent that it is impossible to separate the references; it may be readily distinguished, however, by the forcep-like male plates, while in saratogensis they are nearly quadrate discs. ' GENUS LEPYRONIA A. & S. Vertex, together with the eyes, as wide as the pronotum, angularly rounding anteriorly, the margin sharp, disc nearly flat, without carina, tylus large, parallel margined: ocelli about midway between tylus and pronotum, nearly as far from each other as from eyes; front broad, moder- ately inflated, coarsely ribbed, except along a median band; rostrum, two- jointed, reaching the middle coxa?: pronotum about three times as wide as its length on middle, anterior margin slightly rounding, lateral margins nearly parallel, sharply carinate, shorter than the long diameter of the eye, posterior margin deeply, roundingly emarginate, disc but slightly convex; elytra coriaceous, broad and rather short, outer margin broadly and regularly rounding to the acutely angulate apex; venation of the 218 IOWA ACADEMY OF SCIENCES. normal pattern, often slightly irregular, obscured by the coriaceous struc- ture and the dense pubescence: wings, with the third sector from the marginal one, forked, the intramarginal A'ein interrupted between the third and fourth sectors; legs short and stout, hind tibia armed with two stout spurs and a large crescent of spines: whole dorsal surface covered with a dense prostrate pubescence. Our representatives of this genus are all grayish or brown- ish-cinereous, with traces of oblique fuscous-markings on the elytra; in size they range all the way from that of a Clastoptera up to the largest AphropJtora, but are always easily recognized by their globose forms and hairy covering. SYNOPSIS OF THE SPECIES. A. Margins of the vertex regularly rounding to the obtuse tip: elytra slightly angularly inflated, nearly twi«e longer than their com- bined width (folded), grayish, testaceous, wiuh a distinct V on each elytron. Jf-angularis Say. ^ AA. Margins of vertex straight or concave, the tip slightly produced: elytra inflated, no more than one-half longer than their combined width (folded). B. Small, testaceous, rather narrow; the vertex broad and short; shorter, or only equaling the pronotum in length: apex of elytra broadly subhyaline. angulifera Uhl. ^ BB. Large, nearly uniform grayish: general form globose; vertex longer than pronotum. gibbosa n. sp. ^ LEPYRONIA QUADRANGULARIS Say. ^Cercopis quadrangularis Say. Jour. Acad. Nat. Sci. Phil., VI, p. 305, 1825. Grayish or tawny-brown, with a fuscous spot at the base, another at the apex, and a V on the center of each elytron; margins of vertex convex; elytra only slightly inflated; length 9 7-8. 5mm., Var. lateralis Linn. Black; a broad, light stripe on costa. ^ Var. leucophthalmus Linn. Entirely dark-brown or black. <3 Var. lineatus Fab. Yellowish-white; a median black stripe arising, sometimes on the point of the vertex, sometimes on the pronotum, and extending to the apex of clavus, often enclosing a narrow, light line; a dark stripe on the corium, parallel with the first. , Var. pallidus Sch. Pale yellowish-white. Whatever its color, it may be readily separated from 0 lineatus by the broader, convex form, and the short, obtuse vertex. 15 226 IOWA ACADEMY OP SCIENCES. ^ PHIL^NUS LINEATUS Linn. ^ Cicada lineata Linn. Faun. Suec, 241, 888, 1761. oPtyelus banvitta Walk. List Homop. B. M,, 718, 1851. Pale creamy-yellow with a light stripe along the costa inside of which may be a dark stripe. Smaller and narrower than spumarius, with the elytra nearly parallel margined, the head long and angular; length 4. 5-6. 5mm., width 1.5-2mm. Vertex, flat, nearly right-angled before, the sides rounding, length equal to two-thirds of the width, almost as long as the pronotum, a faint median carina; tylus narrow, longer than width at base, about equal to the rest of the vertex; ocelli equidistant from tylus and pronotum and also from eyes and each other; front broad, strongly ribbed, making an acute angle with the vertex; rostrum short and stout scarcely reaching the middle coxa?, shorter than the front; pronotum small, flat, broadly rounded in front, usually three or four longitudinal depressions on the anterior portion of the disc; elytra nearly parallel margined, the costal margin curved inward on the middle, venation simple, normal, the outer sector of corium forking near the middle of the posterior half of the elytra, forming a-broad discoid cell scarcely three times longer than wide, rounding at the fork; wings with the third vein from the costal vein entire. Color: Above, pale creamy-yellow with a short prostrate, golden pube- scence covering the entire surface, costal area of the elytra pale creamy- white becoming yellowish posteriorly, a dark stripe runs back from either eye crossing the pronotum below the carinate lateral margins, then on to the elytra where they follow the outer sector, fading out posteriorly, a dark spot on the suture just beyond the apex of clavus, sometimes continued as a dark margin around the apex of elytra. In some males the dark stripe spreads out inwardly and covers nearly the whole of the elytra inside the white margins. Front and below darker with a pale longitudinal stripe on either side just below the eyes. Genitalia: Female pygofers no longer than their basal width, narrow- ing apically, exceeded by the long ovipositer, more than half their length; male plates broad at the base curving upward at nearly right angles to the abdomen, their inner margins straight, attingent, outer margins parallel or slightly narrowing to beyond the middle, then widening and forming an obtuse outward angle beyond which they are cut off obliquely, each plate three times longer than wide. Habitat: (Europe). Specimens are at hand from St. Johns, N. B., New Hampshire, and New York, and it has been reported from Nova Scotia, Ontario and Maine. The reports from the middle and western states probably aMretertcPbilineatu.s, as that species is common in those sections, while'^lhieafu.s has not been received from outside of the the eastern states The specimens from New Brunswick are smaller and inclined to be tawny and answer the description of Walker's species (bai^ivitta) from Hudson's Bay so well that there seems to be no doubt but what ongs here. IOWA ACADEMY OF SCIENCES. 227 CUESTA TOPOGRAPHY OF THE CRIMEAN PENIN- SULA. BY CHARLES R KEYES. (\bstract.) At the last meeting of the Academy I discussed briefly some aspects of the geographic development of the Crimea and the northern borders of the Black sea. Since that time certain of the photographs obtained by those who took part in the geo- logical excursions following the International Congress of Geologists, have been received. It is to one of these especially that I now wish to direct your attention. It shows very clearly certain phases of the surface relief of which mention was made last year, and in a way that is rarely ever exhibited to such a great advantage or to such an extent. The photograph is one taken by Mr. R. T. Mallet of Loudon, who was a member of the party. It is through his kindness I am now able to pre- sent it to you. The photograph (plate vii) is, I think, the best one ever secured showing what modern geographers term Cuesta relief. The word cuesta is a recent American acquisition from the Spanish. It is a common word, used in southwestern United States and Mexico to express the same idea that we do by step- and-platform topography. The short, simple and expressive word has been seized with avidity and has been used widely in place of the longer phrase. The development of the Caesta type of surface relief is, briefly, this: A region of slightly tilled strata composed of alternating hard and soft beds is planed off or worn down to a peneplain, or a base-level plain. This grade-plain is one of faint relief, lying slightly above sea level. When such a region again suffers differential uplifting, the agencies of ero- sion actively begin to work anew Long lateral valleys are soon opened out in the soft strata along the strike of the rocks or at right angles to the direction of greatest dips. These 228 IOWA ACADEMY OF SCIENCES. valleys are connected by narrow gorges. Abrupt escarpments form one side of the lateral valleys and long back-slopes the other. A series of gigantic steps are formed. The idea is best expressed by a cross-section (figure 4), which is a diagrammatic one, of the same region in which the photograph was taken. Fig. 4. Cross-section of the Crimea. In this country we have some excellent examples of this type of topography. Besides the great areas in southwest United States, the Black Hills and Ozarks furnish excellent examples, but they are all on such a large scale that the camera cannot satisfactorily reproduce them. Nowhere in this country is it depicted so beautifully as in the region photographed. The photograph was taken from the crest of one of the lofty escarp- ments, just outside of the southern gates of the ancient city of Chufut Kaleh, formerly occupied by the Karaim Jews, but long since deserted and now in ruins. This point is about five miles from Bakhchisarai, 300 years ago the capital of the Tartar Khans, and about forty miles from Sevastopol. The resistant numbers of the couplets forming the escarpments are chalky limestones of Cretaceous age. To the north they are covered by Tertiary deposits. In Iowa we have traces of an excellent illustration of Cuesta topography, in the area occupied by the upper coal measures of the southwestern part of the state. It is best shown, perhaps, in Madison county. Elsewhere it is greatly obscured by heavy drift deposits, which almost completely bury the highest escarp- ments. Only here and there do the latter peep out through the glacial debris. The broad, intervening valleys that once existed are filled by surface deposits to a depth often of i!00 feet. IOWA ACADEMY OP SCIENCES. 229 PERMIAN ROCKS OF EASTERN RUSSIA. BY CHARLES R. KEYES. (Abstract.) In this country the Permian question has long troubled our geologists. For more than forty years it has been discussed, and up to the present time little advancement appears to have been made. Recently, interest has been awakened in the sub- ject, and many workers have begun to attack the problems anew. At first glance the title of this paper would seem to have little bearing upon our Iowa geology. Yet, it is directly to the Iowa part of the question that the present statements are intended to apply. The southwestern part of the state con- tains beds that have been placed in the Permian. In the con- sideration of the so-called Permian beds in America, few workers have been able to compare these formations directly with the original Permian. The information has been largely second hand, and the literature is to a great extent inaccessible on account of being in foreign languages and widely scattered. During the geological excursions that preceded and fol- lowed the sessions of the International Congress of Geologists that were held in St. Petersburg a year ago, a number of American workers, interested in the Permian question, were able to examine pretty extensively the original beds constitut- ing Murchison's system. The examinations were espe^nally instructive, on account of the personal guidance of the Russian geologists, who had long worked in the region. Along the flanks of the Urals, and in the great valleys of the Kama and Volga rivers, the sections were particularly complete. The most remarkable feature about the Russian Paleozoic strata above the Devonian is, that in nearly every respect, they are almost identical with the same parts of the general geolog- ical sections developed in the Mississippi valley, as found in Iowa, Missouri, and Kansas. And, strangely enough, the very 230 IOWA ACADEMY OF SCIENCES. same questions that have so long perplexed investigators in this country, are momentous problems yet not fully solved in Russia. Yet, a comparison between the two widely sep- arated provinces throws some light on our own perplexities. The basins occupied by the upper Paleozoic in Russia, and the Mississippi valley, are very nearly of the same size. In the first mentioned area the Permian very greatly predomi- nates as the surface rock; in the last named, the coal measures. The Carboniferous of Russia presents two very distinct aspects: a thalassic facies, occurring on the western flanks of the Urals, and made up of limestone chiefly; and a shallow water or littoral phase, that is coal-bearing, which is best developed in the southern and western parts of the great area, principally in the Donetz and Toula basins. COMPARISON OF GENERAL SECTIONS. RUSSIA. CHARACTER OF TERRANES. MISSISSIPPI VALLEY. Tartaran, Permo- Trias: or Upper Permian, P3. Shales and marls, red and varie- gated, sandstones, shaly, fos- sils rare, "'red beds." Cimarron series. Middle Permian, P2. Lower Permian, Pib. Upper Permo-Carbonif er- ous (base of equal P), CPc. Limestones, some rtolomitic,and calcareous marl. Shale,only 200 feet thicli in Kama valley. Limestone, heavy, dolomitic. Marion li. 1 !• Series. Chase li. J Artinsk, OP. Shales, sandstones, some thin limestones. I Neosho. - Cottonwood. ( Wabaunsee. Upper Carboniferous, C3. Limestones and shales, highly fossiliferous. Missourian series. Mosconan, Middle Car- boniferous, O2. Shales, sandstones, thin lime- stones, coal-bearing. Des Moines series. Lower Carboniferous, Ci. Limestones chiefly, some shale and sandstone. Misslssippian. In the consideration of a theme like the present one it is recognized at the outset that comparisons of terranes of dif- ferent geological provinces involve no necessary exact syn- chrony, except through absolute physical means of correlation. Such a standard, independent of intrinsic features of the ter- ranes is not yet formulated for widely separated districts. The shortcomings of the common fossil criteria, in any other than the most general way and in the absence of something better, are well known. Any agreement of biotic features in strati- graphic successions distantly removed from one another are IOWA ACADEMY OF SCIENCES. 231 looked upon, so far as indicating their simultaneous origin, only as happy accidents. Instead of furnishing proofs of time equivalency it suggests for similar faunas merely likeness of conditions, irrespective of time. Such faunal facies are only biologically representative. They are merely homotaxial. In lithological and faunal characters the rocks are so nearly alike that it is difficult to fancy that in the Urals one is on the opposite side of the earth from our Iowa and Kansas beds. Among the pertinent questions regarding the so- called Per- mian in this country three are of special prominence. They are: (1) Should the Permian be recognized in America? (2) If so, what is the taxonomic rank? and (3) what are the upper and lower limits of the terrane, so-called? Without going into details of these questions it may be suggested: First.— That while we have in America a great succession of deposits identical in all essential respects to the original Per- mian of Russia, the two great basins merely had similar his- tories that are not necessarily connected, and probably were wholly independent of each other and unrelated; that the Russian Permian constitutes a geological province by itself; and that therefore the term Permian should not be used as a technically exact term in connection with the Mississippi val- ley deposits. Second. — That Permian as originally proposed applies to a provincial series, and according to our usual standard, has at best a taxonomic rank below that of system. Also, in view of the possible elevation of its subdivisions to the rank of series the term will have no position in the scheme of classification. It will be, no doubt, eventually dropped altogether, the various series belonging to the succession being made a part of the Carboniferous system. In this country the same plan has already been proposed. Third. — That, with the solution given to the second question, it is unnecessary to attempt to locate the limits of the so-called Permian in this country. The divisional lines of the series comprising the beds of the typical American section in Kansas are already well defined, with the possible exception of the upper member. The data upon which these conclusions are based are given at length in another place. INDEX Adair county, forest trees of, 56. Address, presidential, 16. Agassiz, A., quoted, 28, 31, 33. Algebra complex extended to threefold space, 202. Anlnials, Jeep sea. the coloration of, 27. Artesian well at Burlington, 70. Bain, H. Foster, 13, 55, 78, 80, 123. Balfour. A. T., quoted, 23, 23. Ball, E. I)., 37-40, 204. A review of the cercopid;B, 204. Baker, cited, 206 Beddard, cited, 32, 35. Beyer, S. W., on buried loess, 117. Big Sioux Valley, old s ill in, 123. Bruner, Professor, mentioned, 213, 214. Burlington, artesian well, 70. Buzzell, Helen M., 127. Calvin, S., quoted, 55, 80. Carpenter, Dr. W. B., cited, 33. Cercopld;B of North America, 204. Chamberlin, T. C. ((uoted. 110. Christian science, alluded to, 120. Chronometer, the lower rapids of the Mississippi as, 92. Cloud-burst in Des Moines county, 66. Coelenterata, coloration, 27. Coloration in deep sea animals, 27. Antipathida>, 31. Cave animals, 35. Oephalopods, 30. Coelopourus. 29. Crustaceans. 28, 30. Echinus. 29. Fishes, 30. Gorgontda-, 28. 31. Hydroldea, 31. Jelly fishes, 31. Luidia. 29. Ophiurians, 29. 30. Pentacrinus, 28. Pennatulida;, 30. Protozoa, 31. Salenia, 29. Salpa, 30. Commensalis-x), invertebrates living in, 2^. Correlation, geological, some physical as- pects of. 131. Chief methods, 137. Conclusion, 152. Foundation of geologic. 134. Methods of geologic; 13S Nature of the problems, 133. Crimean peninsula, topography of, 227. Crustacea, coloration of, 28. Des Moines county, cloud-burst in, 66. Diatoms, preliminary report, 47. Clear lake, 49. Iowa City, 48, 49. Missouri river, 49. Okoboji lake, 51. Spirit Lake, 50. Drift, newllight'on, 122. Echlnodermata, coloration, 27, 28 Fellows, list of, 8. Fellows elected, 15. Fink, B., bibliography of N. A. lichens, 165. Fitch, cited, 204, 205. Fitzpatrick, T. J. and M. F. L., on the flora of southern Iowa, 173. Flora of Southern Iowa, 123. Forbes, S. A., cited. 40. Fowler, cited, 208, 209, 210. Frost, W. D., 116. Fultz, F M., the Burlington Artesian well, 70 Fultz, F. M , quoted, 78. Garretson, So. Dak., observations near, 126. Germar, cited, 301. Goding, Dr , cited, 205. Gordon, C. H , quoted, 83. Gorgonidea, color markings, 27. Gow, Jas. E , 56, 6i. Hall. T. Proctor, 303. Heldermann, Otto, mentioned, 216. Hemiptera, notes on, 36. Heteroptera, 37, 40. Genera described — Harmostes, 38. Homa>mus. 37. Largidea. 38. Lioderma, 37. Mecidia, 38. Mlnoceps, 38. Palococoris, 38. Pamera, 88. Perlbalus, 37. Systratlotus, 38. Localities. Cherokee, 39. Little Rock, 39. Rock Rapids, 39. Sioux City, 39. Sioux Falls, South Dakota, 39. Yankton, South Dakota, 39. lUinoian stage. Erosion preceding, 81. Filling at time of, 83. Glaclation of, 83. Incubator, a simole, 116. Iowa, the tloraof southern, 173. lowan stage, 87. James river. South Dakota, 128. Jassldae, 37. Kansan stage, 82, 93. Kellog, Dr., quoted, 83. Keyes. O. R., 131, 227, 229. Kewatin Ice field, 78, 79, 81. Lake Agassiz, 90. Lake Pepin, 91. Leverett, Frank, 14, 123. 234 INDEX. Lichens, North America— Bibliography of, 165. Liverworts of Iowa, 113. huried in Story county, 117. 118, 119. Loess fossils, distribution of, 98. Genera described— Bipdaria, 104. Cochliopa, 100. Hellicina, 108. Palygyra, 101, 102, 107. Pyramidula, 102. Sphyradlum, 102. Succinea, 99, 100, 101. 102, 104. vitrea, 100. zonitoideas, ICO, 101, 104. Map of Fairmont Park, 112. Near Sioux Palls, 124. Lonsdale, E. H., obituary notice, 12. Mallett, R. T., mentioned, 227. MacBride, T. H., presidential address, 16, McGee, W. J., cited, 55, SO, Merrill. J. W., cited, 68. Michigan, University of, 18. Mississippi river- Lower rapids in, 74. Trough. 122. Mosley, Professor, quoted, 27, 54. Mosses of Iowa, preliminary list of, 154. Muscatine county— Diatomaceous earth, 53 Diatoms of, 52. Myers, P. C, 47, 52, 114. Nebraska, the drift in northeastern, 122. Norton, W. H , 80. Nutting, C. 0., 27. Officers elected, 14. Osborn, Herbert, 16, 216. Notes on Hemiptera, 36. Papers read at 1898 meeting, 14. Pentocrinus, distribution of, 27, 28, Pentatomid;i3, 40. Sub-families— Acanthosominu', 46. Asoplnae, 40. Pentatomina\ 41. Tribes— Acellaria, 42. Halyaria, 42. Pentatomaria, 43 Podoparia, 41. Permian- Comparative table, 230. Question, 229. Rocks of Eastern Russia, 229 Provancher, cited, 204. Ricker, Maurice, 66. Ross, L. S.,116. Sangamon stage, 86. Savage, T. E., 114, 154. Say, cited, 204, 203. Sea urchins, coloration of, 26. Schaeffer, Dr. O. A , obituary notice, 12, cited, 17. Shimek, B., 47, 98, 113. 118, 121, 124. South Dakota, new light on the drift in, 122. Stall, quotPd, 205,208. Steamooat Springs, Colorado, 93. Elevation of, 97. Location of, 93. Stol, cited, 40. Story county, buried loess in, 117. Summers, 206. Thomson. SlrWyville, cited, 33. Todd, J. E,, 122. Tolstoi, Count, (luoted. 24. Turkey ridge, preglacial deposits on, 126. Udden, .1. A., 53. 54, 110, 120. Uhler, P., cited, 204, 219, 223, 225. quoted, 40. Verrill, cited, 33, 33, 38. Warren, cited, 76. 77. Wind deposits, 119. Wisconsin stage, 89. Witter. F. M , 93. Worthen, quoted, 76. PROPERTY OF Z. p. METCALF W^S !)H