4^x JOURNAL OF THE Elisha Mitchell Scientific Society VOLUME XXXVI 1920-1921 ISSUED QUARTERLY Published for the Society by the University of North Carolina CONTENTS Proceedings of the Elisha Mitchell Scientific Society, December, 1916, to March, 1920 i Proceedings of the North Carolina' Academy of Science. . 7 The Theory of Relativity. Andrew H. Patterson 19 A New Method for Laying Out Circular Curves by De- flections FROM the p. I. T. F. Hickerson 42 A Remarkable Form of Skeletal Element in the Lithistid Sponges (A Case of Analogical Resemblance). H. V. Wilson . . • 54 The Turtles of North Carolina. C. S. Brimley 62 A Little-Known Vetch Disease. Frederick A. Wolf 72 Notes on the Mosquito Fauna of North Carolina. Frank- lin Sherman 86 An Interesting Fertilizer Problem. H. B. Arhuckle 94 Azalea atlantica Ashe and Its Variety luteo-alba n. var. W. C. Coker 97 A New Species of Achlya. W. C. Coker and /. N. Couch 100 Proceedings of the Elisha Mitchell Scientific Society, May, 1920, TO December, 1920 103 James Jacob Wolfe, 1875-1920 no The Chemical Behavior of Zirconium. F. P. Venable 115 A Pure Culture Method FOR Diatoms. Bert Cunningham .. . 123 The Occurence of Unlike Ends of the Cells of a Single Filament of Spirogyra. Bert Cunningham 127 Some Marine Molluscan Shells of Beaufort and Vicinity. Arthur P. Jacot 129 Notes on the Thelephoraceae of North Carolina. W. C. Coker 146 DOUBLE NUMBER VOL. XXXVI SEPTEMBER, 1920 Nos. 1 & 2 JOURNAL OF THE Elisha Mitchell Scientific Society CONTENTS Proceedings of the Elisha Mitchell Scientific Society, De- cember, 1916, to March, 1920 1 Proceedings of the N. C. Academy of Science 7 The Theory of Relativity. Andrew H. Patterson 19 A New Method for Laying Out Circular Curves by Deflec- tions FROM the p. L T. F. Hickerson 42 A Remarkable Form of Skeletal Element in the Lithistid Sponges (a Case of Analogical Resemblance). H. V. Wilson 54 The Turtles of North Carolina. C. S. Brimley 62 A Little Known Vetch Disease. Frederick A. Wolf 72 Notes on the Mosquito Fauna of North Carolina. Frank- lin Sherman 86 An Interesting Fertilizer Problem. H. B. Arhuckle 94 Azalea atlantica Ashe and Its Variety luteo-alba n. VAR. T^. C. Coker 97 A New Species of Achlya. W. C. Coker and /. N. Couch 100 ISSUED QUARTERLY CHAPEL HILL, N. C, U. S. A. ENTERED AT THE POSTOFFICE AS SECOND-CLASS MATTER The Elisha Mitchell Scientific Society W. C. COKER, President. J. M. BELL, Vice-President. A. W. HOBBS, F. P. VENABLE, Secretary and Treasurer. Permanent Secretary. Editors of the Journal: "W. C. COKER. COLLIER COBB. J. M. BELL. JouBNAii OF THE Elisha Mitchell SCIENTIFIC SOCIETY — Quarterly. Price $2.00 per year; single numbers, 50 cents. Most numbers of former volumes can be supplied. Direct all correspondence to the Permanent Secretary, at the University of North Carolina, Chapel Hill, N. C. In addition to original papers on scientific subjects this Journal pub- lishes the Proceedings of the Elisha Mitchell Scientific Society, and the Proceedings of the North Carolina Academy of Science, as well as abstracts of papers on scientific subjects published elsewhere by members of the Faculty of the University of North Carolina. Published for the Society by the University of North Carolina PLATE 1 ^; / AZALEA ATLAXTICA. (left) AZALEA ATLANTICA VAR. LUTEO-Al-BA. niutit) i Natural Size JOURNAL OF THE Elisha Mitchell Scientific Society Volume XXXVI SEPTEMBER, 1920 Nos. 1 and 2 PROCEEDINGS OF THE ELISHA MITCHELL SCIENTIFIC SOCIETY, DECEMBER, 1916, TO MARCH, 1920. 225th Meeting — December 12, 1916 m'", , A. H. Patterson — Shrapnel in the Making. ''■ ' J. M. Bell — Some Recent Work in Crystal Structure. 226th Meeting — February 20, 1917 H. H. Williams — The Logic of Science. Collier Cobb — Recent Changes in Currituck Sound (Illustrated). 227th Meeting— March 13, 1917 H. R. ToTTEN — Growing Mushrooms in Pure Culture. J. S. Holmes — Some Notes on the Occurrence of Landslides. Business Meeting — September 26, 1917 Election of Officers : President — J. G. Beard, Vice-President — J. M. Bell. Permanent Secretary — F. P. Venable. Recording Secretary — W. W. Rankin, Jr. Editorial Committee — W. C. Coker, chairman ; Collier Cobb, M. H. Stacy. 228th Meeting — October 9, 1917 c^ P. H. Daggett — Modern Tendencies in Engineering Education. en F. P. Venable — The Luminosity of Insects — A Chemical Phenom- Oi CD enon. [1] 2 Journal of the Mitchell Society [September 229th Meeting— November 13, 1917 Collier Cobb — Cave Dwellings (Did their Relation to Geolofji/. 230th Meeting — December 11, 1917. W. deB. MacNider — The Stahintu of the Acid-Base Equilibriioii of the Blood in Animals of Different Ages. Archibald Henderson — The Role of Pascal's Theorem in Modern Geometry. 231st Meeting— February 26, 1918 H. V. Wilson — Contributions of French Scientists as Brought out at the San Francisco Exposition. H. W. Chase — Some Modern Tendencies in Psychological Thought. 232d Meeting— March 12, 1918 W. C. CoKER — Corn {Illustrated) . A. S. Wheeler — The Production of Toluol. 233d Meeting— April 9, 1918 J. W. Lasley — Some Everyday Problems. F. P. Venable — Luminescence and Radioactivity of the Zircons. P. H. Daggett — Demonstration of a New Telephone Signaling System. Business Meeting — October, 1918 The old ofi&cers were re-elected for the year 1918-19, during which period the regular meetings were suspended. 234th Meeting— April 15, 1919 Archibald Henderson — Some Points in Gunnery for Heavy Ar- tillery. F. P. Venable — The North Carolina Academy of Science. 235th Meeting— May 13, 1919 W. deB. MacNider — Influence of the Age of an Organism on Regen- eration. A. S. Wheeler — New Napthalene Dyes. J. M. Bell — Investigations on the Nitrotoluenes. 1920] Proceedings of Elisha Mitchell Scientific Society 3 Election of Officers: President — W. C. Coker. Vice-President — J. M. Bell. ♦ Permanent Secretary — F. P. Venable. Recording Secretary — A. W. Hobbs. * Editorial Committee — W. C. Coker, chairman; J. M. Bell, Collier Cobb. 236th Meeting — November 11, 1919. H. V. Wilson — Some Crustacea of the North Carolina Coast. F. P. Venable and D. H. Jackson — Reactions of Hydrochloric and Hydrobromic Acids with Potassium Permanganate. 237th Meeting— December 9, 1919 J. N. Couch — A New Species of Water Mold with Ohservations on Fertilization. T. F. Hickerson — A New Method For Laying Out Curves in Road Location. 238th Meeting— January 13, 1920. J. J. Wolfe — The Plankton of Chesapeake Bay. The speaker presented in brief form the results obtained in a plankton survey of these waters, made by the speaker in collaboration with Prof. Bert Cunningham, the object of which was to throw some light on the kind and abundance of organisms that may serve as fish food. The collections on which the work was based were made by the U. S. Bureau of Fisheries. The details of collection and the methods employed in the study were explained at some length. Charts and tables compiled from the data gathered were presented and the conclusions drawn which may be summarized as follows : 1. The volume of matter suspended in the water bears little or no relation to the number of organisms present. 2. There is a gradual increase in volume with increasing depth due in part to detritus and in part to an increase in organisms. 3. There is a great variation in number of organisms in different parts of the Bay on the same day and at the same depths, the cause of which is not determined. Locations and temperature are ruled out as causes. The data, too meagre as yet, point to the tides as a possible explanation. 4 Journal of the Mitchell Society [Septeinher 4. There are two crests during the year, April-May and Sep- tember-October, due to a tremendous increase of individuals belonging to only ojie or two species rather than as might be expected to a gen- eral increase in all species represented. 5. There seems to be a definite relation between temperature and number of organisms, the optimum lying between 46° and 55° F. 6. There is a noteworthy absence of Copcpods certainly due to some error in the method of collection. 7. Neither ''count" nor "volume" gives an absolutely true in- dication of food available. These two in connection with "incinera- tion" would probably give a more correct idea. 239th Meeting— February 10, 1920 F. P. Venarle — The Chemistry of Zirconium. This paper will be published in full in this Journal in a later number. W. F. Prouty — Notes on the Geology of a Portion of Clay County, Alabama. The fundamental or metamorphic rocks of Clay County, Alabama, have been generally considered of Precambrian age. There is nothing published concerning the age of the associated intrusives. Dr. Smith, of the University of Alabama, has demonstrated the Carboniferous age of a small area in the phyllites of western Clay County. The speaker has recently widely extended, in the phyllite belt, the area of known Carboniferous rocks and has demonstrated the post Car- boniferous age of the belt of green schists which everywhere separate the phyllites on the west from the mica schists on the east. The workable flake graphite ores or the mica schist belt are shown to be of epigenetic origin and the association of the ores with the more quartzitic and coarse-grained, originally sedimentary beds, leads to the conclusion that the graphitic ores resulted from the metamorphism of petroliferous strata. 240th Meeting — March 9, 1920 J. F. Dashiell — Double Habit Formation by Animals, Children, and Adults. The problem approached was that as to the relative efficiency of learning two habits by practicing them alternately (the Alternate 19^:0] Proceedings of Elisha Mitchell Scientific Society 5 Method) or by getting one to some extent fixed before practicing the other (the Complete Method). Data were obtained by the study of the learning of mazes by rats, of mazes by children, and of mazes by adults ; then the scope was extended to include the formation of another pair of perceptual-motor habits, card sorting, and further still to include a pair of habits involving very little of the motor element, addition. The particular technique of the different experiments was inten- tionally varied considerably: (a) in temporal distribution of trials; (b) in stage at which shift was made from one to the other habit by the Complete Method; (c) in arrangement of controls— division of subject into groups; (d) in methods of scoring; (e) in incentives used, (f) in subjects' previous familiarity with the habits to be learned; (g) in their knowledge of the number and order of the habits to be learned; (h) in their knowledge of the nature of the problem inves- tigated. Thus, the general results found may be considered as inde- pendent of particular details of technique and to be of general bearing. For results, it was found that in all the forms of double habit for- mation studied, learning by the Complete Method was more economical than learning b}^ the Alternate Method. This was indicated in the different sets of experiments in terms of the different criteria of effici- ency respectively applicable. They included: (a) number of trials necessary to fix a habit; (b) degree of regularity in improvement ; (c) average amounts of scores on individual trials; (d) rate of accelera- tion of improvement. The complete paper will appear in an early number of The Psy- chological Review. J. B. Bullitt — Report on Autopsies on 25 Cases of Influenza Pneu- monia. Extensive cutaneous emphysema v^as encountered in one case. Firm, fibrous pleural adhesions existed in six cases, in four of which the lungs showed old scars of apparently healed tuberculosis while one showed fibrinous exudate on the pleura, four of these exudates being thick and shaggy. In three of these there was serous effusion ; in two, purulent effusion. All cases exhibited the lobular type of pneumonia. In seven there was also distinct lobar consolidation, the lobular process in these being but slightly evident. Numerous bronchiectatic abscesses occurred in four cases, while in four others (three of them associated with labor consolidation) there was massive 6 Journal of the ^Mitchell Society [Septemher necrosis involving tlie whole or the greater part of a lobe. .Meningitis existed in five eases — two due to the meningoccocus, one to the nienin- goeocciis and pneumococcus together, while in two the organism was not discovered. In all cases of more than one week duration more or less extensive organization has occurred. Two men who lived about five weeks died suddenly during apparent convalescence. The lungs showed little evidence of active inflammation, but organization has obliterated the greater part of the pulmonary tissue. These seem analogous to those cases of nephritis in which the repair process strangles the glomeruli and kills a patient who may have survived the original toxemia. PROCEEDINGS OF THE NINETEENTH MEETING OF THE NORTH CAROLINA ACADEMY OF SCIENCE, HELD AT STATE COLLEGE, WEST RALEIGH, N. C, APRIL 30-MAY 1, 1920. The executive committee met in the offices of Prof. Z. P. Metcalf April 30, at 12 :00 M., with the following members present : President A. H. Patterson, Secretary R. W.' Leiby and member Z. P. Metcalf. The secretary made a preliminary report on finances, membership, etc., following which the policies of the Academy and other questions were discussed. A total of 28 new members were elected as follows : JosiAH S. Babb, Asst. in Geology, U. N. C, Chapel Hill. Dr. H. p. Barret, Physician, Charlotte, Wm. Hande Browne, Prof. Elec. Engr., State College, West Raleigh. Dr. J. B. Bullitt, Prof. Path., U. N. C, Chapel Hill. J. N. Couch, Asst. in Botany, U. N. C, Chapel Hill. Dr. J. B. Derieux, Dept. Physics, State College, W. Raleigh. A. A. Dixon, Dept. Physics, State College, W. Raleigh. Paul Gross, Ph. D., Chemist, Trinity College, Durham. Miss Pattie J. Groves, Instr. Science, Durham High School, Dur- ham. V, R. Haber, Asst. Investigations, Ent., State Dept. Agr., Raleigh. Dr. J. 0. Halverson, Expert Animal Nutrition, State Dept. Agr., Raleigh. C. M. Heck, Dept. Physics, State College, W. Raleigh. Miss Alma Holland, Asst. in Botany, U. N. C, Chapel Hill. J. E. IvEY, Poultry Path., State College, W. Raleigh. S. G. Lehman, Asst. Plant Path., State College, W. Raleigh. A. L. Lugn, Prof. Physics and Chemistry, Lenoir College, Hickory. Dr. Wm. F. Prouty, Stratigraphic GeoL, U. N. C, Chapel Hill. R. F. Revson, Chemist, 210 S. Tryon St., Charlotte. G. H. Satterfield, Trinity College, Durham. Prof. M. E. Sherwin, Prof. Soils, State College, W. Raleigh. I. V. Shunk, Asst. Prof. Botany, State College, W. Raleigh. M. R. Smith, Extension Ent., State Dept. Agr., Raleigh. Ira W. Smithey, U. N. C, Chapel Hill. [7] 8 Journal of the Mitchell Society [Septemher Haywood M. Taylor, U. N. C, Chapel Hill. Dr. Walter F. Taylor, Asso. Prof. Bacter. and Hyo-iene, W. F. C, Wake Forest. Dr. B. W. Wells, Prof. Botany, State College, W. Raleigh. C. B. Williams, Dean, State College, W. Raleigh. J. H. Williams, Instr. Zool. & Ent., State College, W. Raleigh. The executive committee then adjourned. At 2 :15 P. M. the first session of the annual meeting was called to order by Pres. A. H. Patterson, who made some remarks chiefly concerning the time allowance for presentation of papers. The fol- lowing committees were then appointed : Auditing — C. S. Brimley, T. F. Hickerson, F. A. Wolf; Nominations— eJ. J. Wolfe, W. C. Coker, W. A. Withers; Resolutions — C. W. Edwards, H. B. Arbuckle, Miss Mary Petty. Papers were then called for, the reading and discussion of which was carried on until 5 :00 P.M. when the session was adjourned. The Academy reconvened at 8 :]5 P. M. to listen to the Presidential address by A. H. Patterson on "The Einstein Theory of Relativity." Previous to the presidential address, the Academy was formality wel- comed by Dr. W. C. Riddick, President of the College, the response being made by Professor Patterson. The Academy was again called to order on Saturday morning at nine o'clock for a business session. The Secretary read the minutes of the previous meeting, which were approved. The Treasurer's re- port was read and referred to the Auditing Committee. The matter of increasing dues was discussed. Professor Metcalf presented the pro- position of the Academy affiliating with the American Association for the Advancement of Science. This was freely discussed and re- ferred by motion to the Executive Committee with power to act. The question of securing State support for the Academy in the sum of $500.00 to $1,000.00 was discussed and motion was adopted to refer to Executive Committee to look into matter and if found practicable to authorize the President to appoint a committee to present the matter to the next Legislature. The committee on Science Instruction in the High Schools as related to the College, was continued with one change in personnel, the substitution of Mr. Bert Cunningham for Dr. J. J. Wolfe. Motion was then adopted, following pro and con discussion, that the Secretary be allowed ten per cent of all moneys collected by him for the Academj^ effective next year. lyW] Proceedings of the Academy of Science 9 Motion adopted that we accept the invitation of Wake Forest Col- lege to meet there next year. The nominating committee then made its report as follows : President— Z. P. Metcalf, W. Raleigh. Vice-President— J. M. Bell, Chapel Hill. Secretary-Treasurer — R. W. Leiby, Raleigh. Additional members Executive Committee : H. R. Totten, R. N. Wilson, F. A. Wolfe. Report was adopted and Secretary authorized to cast the ballot. Motion was then adopted that the following telegram be sent past President and Secretary, E. W. Gudger: "The North Carolina Academy of Science in annual session assembled, deeply appreciating the splendid constructive service which you rendered her through so many years, sends you greeting and begs that you accept her thanks for this most devoted service which we well know was a labor of love, and sincerely hopes that events may so shape themselves that you may at an early date again actively share in her work and achievement. ' ' Following the business session the presentation of papers was con- tinued before the joint session of the Academy and Chemists until 12 :30. At 1 :30 the Academy reconvened for the further presentation of papers. During this session the report of the Auditing Committee was adopted which found the books correct and suggested the payment of the nominal sum of $5.00 to the Secretary's stenographer for clerical work. The report of the Resolutions Committee was then read and adopted as follows : Resolved, That we, the members of the North Carolina Academy of Science, sorrow because of the demise of our member and fellow worker, Mrs. Fannie Carr Bivins, head of the Science Department of the Durham City Schools, and express our recognition of her unselfish and enthusiastic work as student and teacher which made her life such a notable contribution to the advancement of science in her community. That we express our hearty appreciation of the kindness, courtesy, and co- operation of the President and Faculty of the N. C. State College of Agriculture and Engineering on the occasion of the nineteenth annual meeting of the Academy and especially of the generous and hospitable manner in which we have indi- vidually been entertained. Following the completion of the program the Academy adjourned sine die at 3:15 P.M. 10 Journal of the Mitchell Society [September Report of Treasurer, July 1, 1919-April 28, 1920 Keceipts Expenditures From former treasurer $ 128.67 Eubber stamp $ 1.00 Dues (back) 5.00 Postage and envelopes 13. 72 Dues (current) 56.00 Stationery 5.25 Dues (advanced) 16.00 Multigraph letters (3) 3.00 Initiation fees 28.00 Printing programs 16.50 Savings acct. Int 3.32 Incidentals 1.20 Total receipts .$ 236.99 $ 40.67 Total expenditures 40.67 $ 196.32 Balance April 28, 1920 $ 196.32 Balance May 31, 1920 (all bills paid) $ 156.09 Following is present membership of the Academy. Those marked with asterisk were in attendance at meeting : Andrews, W. H Chapel Hill *Arbuckle, H. B Davidson Babb, Josiah S •■ ■••• Chapel Hill Bahnson, F. F Winaton-Salem Balderston, Mark Guilford College Barret, H. P Charlotte Beardslee, H. C Asheville *Bell, J. M Chapel Hill Binf ord, Eaymond Guilford College Bonney, Miss F. C Hartsville, S. C. Bottum, Miss F. E Ealeigh Brewer, C. E Ealeigh *Brimley, C. S Ealeigh Brimley, H. H Ealeigh *Browne, Wm. Hande W. Ealeigh Bruner, S. C Santiago do las Vesgas, Cuba Bullitt, J. B Chapel Hill Bynum, J. C Chapel Hill Cain, Wm Chapel Hill Clapp, S. C Swaunanoa *Cobb, Collier Chapel Hill Cobb, Wm. B Columbia *Coker, W. C Chapel Hill Collett, E. W Willard Coman, J. H Durham *Couch, J. N Chapel Hill 1920] Proceedings of the Academy of Science 11 Cimiiingham, Bert Madison, Wis. Davis, H. T Chapel Hill *Derieux, J. B W. Ealeigh *Dixon, A. A W. Ealeigh Dixon, L. F Weaverville Dobbins, C. N Chapel Hill DoAvning, J. S Elsmere, Del. *Edwards, C. W Durham Edgerton, F. N., Jr Athens, Ga. Farmer, C. M Troy, Ala. *Gross, Paul Durham, N. C. *Groves, Miss Pattie J Durham Gudger, E. W Greensboro *Haber, V. R Raleigh *Halverson, J. O Raleigh Hatley, C. C Durham *Heck, C. M West Raleigh Henderson, Archibald Chapel Hill Hewlett, C. W Greensboro *Hiekerson, T. F Chapel Hill Hobbs, A. W Chapel Hill Hoffman, S. W Statesville *Holland, Miss Alma Chapel Hill Holmes, J. S Chapel Hill . Ives, J. D Charleston, S. C. *Ivey, J. E West Raleigh Johnson, E. D Asheville *Kilgore, B. W R^leigji *Krausz, H. B Raleigh Lake, J. L Wake Forest Lanneau, J. F ..Wake Forest *Lehman, S. G West Raleigh *Leiby, R. W Raleigli Lewis, R. H Raleigh Lugn, A. L Hickory Lyon, Miss Mary Red Springs *Marion, S. J Raleigh Markham, Blackwell Chapel Hill Mendenhall, Miss Gertrude W Greensboro *Metcalf, Z. P West Raleigh Nowell, J. W Wake Forest ^Patterson, A. H Chapel Hill *Pegram, W. H Durham Petty, Miss Mary Greensboro *Pillsbury, J. P West Raleigh *Plummer, J. K Raleigh Poteat, W. L Wake Forest 12 Journal op^ the Mitchell Society {Srpffmhpr Pratt, J. H Chapel Hill *Prouty, Wm. F •• Chapel Hill Randolph, E. O College Station, Texas Randolph, Mrs. E. O College Station, Texas Rankin, W. S Raleigh *Revson, R. F •• Charlotte *Rhodes, L. B Raleigh *Riddick, W. C West Raleigh *Robinson, Miss Mary Greensboro *Satterfield, G. H West Raleigh *Saville, Thorndyke Chapel Hill Seymore, Miss Mary F Greensboro Shaffer, Miss Blanch E Greensboro *Sherman, Franklin Raleigh Sherrill, Miss Mary L •• Greensboro *Sher\vin, M. E West Raleigh *Shore, C. A Raleigh *Shunk, I. V West Raleigh Smith, J. E Ames, Iowa *Smith, M. R Tallulah, La. Smithey, Ira W Chapel Hill *Spencer, Herbert West Raleigh Stiles, C. W Wilmington Taylor, Haywood M Chapel Hill Taylor, Walter F Wake Forest *Totteu, H. R Chapel Hill Vann, Miss Fannie E Durham Venable, F. P Chapel Hill *Wells, B. W West Raleigh *Wheeler, A. S •■ Chapel Hill *Williams, C. B West Raleigh *Williams, J. H "West Raleigh *Williams, L. F West Raleigh *Wilson, H. V Chapel Hill * Wilson, R. N Durham *Winters, R. Y West Raleigh *Withers, W. A West Raleigh *Wolf, F. A West Raleigh *Wolfe, J. J Durham, N. C. Total membership, 113. The following: papers were presented at the meeting- : The Einstein Theori; of Relativity. A. H. Patterson. (Presidential address). Appears in full in this issue. ].9,20] Proceedings of the Academy of Science 13 A New Method for Laying out Circular Curves. T. F. Hickerson. Appears in full in this issue as a new method for laying out circular curves by deflections from the P. I, A Remarkable Form of Skeletal Element in the Lithistid Sponges {A Case of Analogical Resemblance. H. V. Wilson. Appears in full in this issue. Animal Locomotion. H. H. Brimley. This paper treats of the means used in moving from place to place bj^ the fishes, amphibians, reptiles, birds and mammals. The species in each class are artificially grouped according to their main locomotion characteristics. Together with what may be called their normal methods of pro- gression, the paper treats of fish that can walk and mammals that cannot ; of mammals that can fly and birds without such powers ; of reptiles that possess the power of volplaning through the air; of fish that travel while lying on the side ; of mammals that use three or five members in their movements ; of others that spend their lives upside down ; of fish that possess the power of movement through the air ; of birds that swim and dive while young and lose such powers on becoming adult ; of mammals possessing exceptional locomotive powers both on land and in the water, and of birds that walk, fly, swim, dive and climb. Single Spore Cultures of Coprinus radiatus. H. R. Totten. Reports the growth to maturity of Coprinus radiatus Fr. from a single spore. Mycelia from a spore germinated in broth of horse manure, and transferred to the following media, formed mature plants : Horse manure, cow manure, horse manure agar, corn meal agar, and peas. A review was given of Mile. Bensaude's thesis on "Sexualite chez les Easidomycete, " Paris, 1918, in which she proves that Coprinus fimetarius is a dioecious fungus. Coprinus radiatus was compared with Coprinus fimetarius and was shown to be monoecious. The hyphae of Coprinus radiatus also lacks the clamped connections so commonly seen on hyphae and always seen on the hyphae of Co- prinus fimetarius before the formation of mature plants. 14 JouRXAL OF THE MiTCiiELL SociETY [Septemher Genera of Lower Basidiomycetes not Before Reported from North America. W. C. Coker. Reports the occurrence in Chapel Hill of three Genera; all grow- ing on wood as saprophytes, and forming small pustules or expanded, resupinate layers. They are as follows: Saccohlastia Moller. A remarkable genus with elongated basidia divided across into four cells as in the rusts ; and arising in a peculiar way from the tip of a pendant pear-shaped sac. Three species have been reported, two from South Brazil and one from Poland. Our plant is considered a variety of S. ovispora Moller from South Brazil. Platygloea Schroeter. Two species were found on Crepe Myrtle, both of which seem new. About nine others have been described from Europe and the tropics. Our plants seem nearest Helicogloea Lager- heiini Pat. which is usually considered as not generically distinct from Platygloea. Our species have small, crowded basidia borne in corymbs and two-celled bj' a cross partition. Sirohasidium Moller. In this genus the basidia are borne in chains and are divided into two cells by an oblique wall or into four cells by longitudinal walls. Three species have been described, all fi-om South America (one from Brazil, two from Equador). Our plant agrees well with the one from Brazil, S. Brefeldia)ui))i Moller. Attention was also called to the Genus Septobasidiioii, which is well represented in America, but in which the basidia have been misunder- stood. The Turtles of North Carolina. C. S. Brimley. Appears in full in this issue. The Life History of a Gall-Making Psyllid {Pachypsylla mamma Riley). Lantern. Dr. B. W. Wells. Oviposition on under side of young hackberry leaf. Nymph mi- grates to upper side of leaf where galls are initiated near the principal veins. Nymph grows very slowly at first while gall on the other hand grows very rapidly. Usualh' but one insertion of the mouth- parts into the leaf tissue is made, the insect keeping its position for an extended period. The nymph escapes from the gall in the fall, the adults appearing immediately afterward. These overwinter in bark crevices or ground debris. 19:^0] Proceedings of the Academy of Science 15 Dreams and their Causes. C. S. Brimley. Paper gives concisely the author's opinion as to the causes of dreams, and illustrates the same by examples from his own personal experiences. A Little-Knoivn Vetch Disease. Frederick A. Wolf. Appears in full in this issue. Notes on the Mosquito Fauna of North Carolina. Franklin Sherman. Appears in full in this issue. The Larger Corn Stalk-Borer {Diatrae zeacolella Dyar). Lantern. R. W. Leiby. Brief references to life-history as determined over a period of 5 years in North Carolina. Discussion of control measures which in- cluded late planting of corn and destruction of overwintering larvae by plowing out corn stubble in fall. An Interesting Fertilizer Frohlem. H. B. Arbuckle. Appears in full in this issue. A Phenomenal Shoot. Dr. B. W. Wells. A shoot found by Mrs. B. W. Wells near Raleigh, N. C, which measures 19 feet, 5 inches in length, was exhibited. It had grown from the stump of a beheaded tree of Paulownia tomentosa during the season of 1919. The base is 7.75 inches in circumference 2.50 inches diameter. The shoot possessed 20 internodes, the longest of which measures 19 inches. A Peculiar Mycorhiza-forming Rhipzopogon on the Roots of Pine. H. R. TOTTEN. Specimens of a species of Rhizopogon were shown on the roots of Pimis Taeda and Pinus echinata. This fungus attacks the young rootlets, forming a mycorhizal covering about each rootlet in a cluster. The fungal coats of several rootlets soon coalesce into a light creamy 16 Journal of the Mitchell Society [September mass of various forms and sizes. The fungus attacks the pine tissue, completely destroys the mass of enclosed rootlets, and remains lightly attached to the root. Many irregular cavities lined with basidia and spores are formed. The interior becomes a dark jelly mass, and the tougher coat later also breaks down. Effect of Fertilizers on Germination and Seedling Growth of Conn and Cotton. M. E. Sherwin. This paper shows the effect of fertilizers on time required for germination and on rate of seedling growth of corn and cotton grown in galvanized pans 3i/^ inches each way. These results are in part in confirmation of field observations. Heavy applications of soluble mineral fertilizers cause the greater delay in germination. Organic fertilizers cause the greater injury to the seedlings. Where germination seems to be poor as determined by the per cent of seeds which have "come up" the trouble will usually be found to be due to root injury where organic fertilizers are used and to inability of the seed to absorb sufficient water where mineral fertilizers are used. To obviate the difficulty in germination and the root injur.y from organic fertilizers no fungicidal treatment has availed. Injury is less severe when the fertilizer is well mixed with the soil but to wholly obviate these troubles the fertilizer should be applied to the soil a week in advance of planting the seed. The injury appears to be much less in soil containing abundance of acid organic matter than in ordinary sand clay soils. The injury appears worse at high temperatures than at low temperatures. The viability of the seed does not seem to have been impaired by contact with the soil solution containing sufficient nitrate of soda to prevent germination in two weeks' time. Increasing the quantity of nitrate of soda has the same effect on rate of germination as decreasing the amount of soil moisture. Borax, either alone or in trona-potash, is decidedly harmful to germination. Very small amounts of borax cause almost complete chlorosis of corn seedlings. 1920] Proceedings of the Academy op Science 17 Some Investigations on the Compounds Isolated from the Polypores. Joseph T. Maddox and Raymond Binford. There has been little or no investigation done on the chemical analysis and isolation of the various compounds present and obtainable from any Polyporus. An investigation was made this past winter towards isolating under various conditions as many compounds as possible. Some eleven different compounds were obtained, which, owing to the lack of proper laboratory equipment, are as yet uniden- tified. This paper is only intended to give an account of the methods used and a study of the physical properties of each compound isolated. Netv Ethers. A. S. Wheeler and S. C. Smith. A new group of ethers has been derived from chloral. The addition product obtained by the action of one mole of chloral upon one mole of m-nitroaniline is boiled with an alcohol. A molecule of water splits off and an ether of strong crystallizing power is obtained. These ethers are sensitive to acids but stable towards alkalies. The reaction with p-nitroaniline is best carried out by first making the chloral alco- holate and then treating this with the amine. The series of ethers under preparation include the three nitroanilines and methyl, ethyl, n-propyl, n-butyl and isoamjd alcohols. p-Cyinenc, A New Solvent. A. S. Wheeler. p-Cymene is now produced on a much larger scale than formerly since it is so easily obtained from spruce turpentine. It becomes, therefore, a useful solvent for high temperatures, its boiling point being 176.5°. It is a colorless hydrocarbon of the benzene series and is to be preferred where possible to such colored solvents as aniline and nitrobenzene and ill-smelling ones as pyridin. The solubility of a num- ber of compounds of a wide range of types has been determined. A Color Reaction for p-Cymene. A. S. Wheeler. In p-cymene obtained from spruce turpentine are one or more impurities which give a color reaction with p-anisidine. The solid p-anisidine may be used or a solution in pure cymene. In samples where the cymene is still yellowish the coloration is very pronounced and is really not needed. The immediate coloration is pale yellow, deep yellow, brown or red depending on the degree of impurity. 18 Journal of the Mitchell Society [Septentber Further in all cases the color deepens very noticeably in succeeding hours. If no coloration occurs in the diffused light of the laboratory within two hours the cymene is pure. The following papers were read but no copies or abstracts fur- nished : Some Biological Aspects of the Tidal Zone Region of the North Car- olina Coast. Z. P. Metcalf. Recent Growth and Depletion of Sea-heaches on the North Carolina Coast. Collier Cobb. Electro-end osmosis of Clays. Thorndyke Saville. Effect of Borax on Plant Growth and Notes on a Method for its Quan- titative Determination in Fertilizers. Oscar J. Theis, Jr., and H. B. Arbuckle. Dyestuff Situation in the United States. R. F. Revson. Agricidtural Geology (Read by title). John E. Smith. The Wing Venation of the Heteroptera. Herbert Spencer. Vitamines — A Review. W. A. Withers. Further Studies on the Melting Points of the Nitrotoluenes. J. M. Bell. A List of the Cicadellidae Taken at Swannanoa, North Carolina. 7i. P. Metcalf and Herbert Osborn. The Conductivity of Nonaqueous Solutions. Paul Gross. Behind the Barrier Beaches from Boston to Beaufort. Collier Cobb. Some Neiv Types of Distillation Apparatus. Paul Gross. R. W. Leiby, Secretary. THE THEORY OF RELATIVITY* By Andrew H. Patterson The idea of Relativity is not new. It was presented by the old philosophers, and has been a constant part of philosophical doctrine to this day. AH of our knowledge is relative. Especially is this true of our knowledge of time and space. We know time only at a certain place ; we observe the position of a point only at a certain time. To say that an observation or measurement was made at a given time is useless and meaningless until we have stated the place, — Greenwich or Washington or Tokio, — to which the time is referred. Places of stars in \he Nautical Almanac are given only for the epoch, or time, stated at the head of the page, and corrections must be applied for later dates. It is quite true to say that we do not kuow the exact place of a star unless we know the exact time. Important dates in Assyrian history have been fixed because of the record of a total eclipse of the sun which was seen in the streets of the city of Nineveh at half -past nine on a certain morning of a certain month of a certain year in the reign of Jeroboam the Second. By calculating when this eclipse must have occurred at that particular place at that time of the morning, we at once link up the Assyrian era to our own, and can translate their time into ours. Time without position in space has no more inde- pendent existence than the direction "vertically upwards", for ex- ample, which changes with every point on the earth's surface. But to fix the place of a point we need a system of axes to which we can refer its position by means of co-ordinates. The latitude and longitude of a ship are the two co-ordinates which fix its position on the surface of the ocean. If the point is to be fixed in space, three co-ordinates are needed, and if we can conceive of a four-dimensional space, four co-ordinates will be necessary to specify the position of any point therein. It is immaterial whether we choose rectangular axes, or oblique axes, or whether we use polar co-ordinates or some other system, pro- vided that the position of the point arrived at by any system is the same. Again, we can transform the co-ordinates of a point in one sys- tem of axes into its co-ordinates in another system of axes by appro- priate mathematical operations, and since a line is a series of points, * Presidential Address, delivered before the North Carolina Academy of Science, at the North Carolina State College of Agriculture and Engineering, Raleigh, April 30, 1920. [19 ] 20 Journal of the Mitchell k50C1etv [^September we can also transform the equation of a line with reference to one set of axes into another equation representing the same line referred to another set of axes. The only criterion for the validity of such a transformation is that the length, curvature and position of the line as given' by the two equations, each referred to its own set of nxes, shall be the same. And this point is to be emphasized: wliilc we may not be able to conceive of a four-dimensional space, the mathema- ticians find no difficulty in getting the appropriate equations referred to four rectangular axes, and of course containing four co-ordinates, and these equations are as mathematicall.v true and consistent as though we habitually used four dimensions in ordinary life. But in using a set of axes, they must either be fixed, or els« their position and motion must in turn be referred to some so-called "frame of reference" that is fixed, and the attempt to find such a frame of reference led to the modern theory of Relativity. Of course the earli- est use of co-ordinate systems was in connection with Astronomy, and the first frame of reference was the supposedly fixed Earth, which Ptolemy, the Alexandrian astronomer who lived in the second century A. D., believed to be the center of a universe of planets and stars which revolved about it, and he referred their positions and motions to the stationary earth as his frame of reference. It is true that four hun- dred years earlier Aristotle and Aristarchus pointed out that by the laws of relative motion the movements of the celestial bodies could be equally well explained l)y a stationary sphere of stars and a revolving eartli, ])ut the learned men of the succeeding centuries followed Ptol- eni}', and it was not until the middle of the sixteenth century that Copernicus put forth again the theor.v that the starry sky, or "eighth sphere", should be considered at rest, and the sun also as its motion- less center, while to this fixed frame of reference should be referred the motions of planets, comets, earth Pud moon. But since this trans- formation of axes — this change in the frame of reference — involved the demotion of the earth from its former proud position of center of the universe to a modest place among the minor planets, Copernicus' theory was bitterly opposed by theologians, both Protestant and Ro- man, on the idea that the new order involved great danger to the teach- ings of the church. Martin Luther denounced Copernicus roundly as an "upstart astrologer" who showed a lack of "public decency" in maintaining that neither the sun lior the "eighth sphere" revolved about the earth. But the new theory had come to stay, for it explained 1!^:^0] The Theory op Relativity 21 clearly and simply the cause of the loops in the paths of the planets, the phases of Venus and the Moon, and the motions of planets, satel- lites and comets. It led very soon to the discovery of Kepler's laws and the epoch- making work of Newton, including the development of the Newtonian mechanics and the differential and integral calculus. Two hundred years after Copernicus, Herschel again upset our frame of reference, for he showed that the whole Solar System is moving through space with a velocity of something like fifteen miles a second in the approximate direction of the star Vega, and that in addition the "fixed stars" are anything but fixed. All of them seem to be travelling in different directions through space with enormous velocities. One of them, in- deed, No. 1830 in Groombridge's catalogue, has such a large proper motion that it is called the ' ' runaway star. ' ' So our fixed frame of reference again fails us, and in our attempt to find another we adopted the theory of a stationar^^ ethei* filling all space, and affording the medium in which light waves are propagated. Such a medium seemed necessary to explain the experiments in optics, electrostatics, magnetism and electromagnetism, and since the same kind of medium with the same properties was needed for the explana- tion of phenomena in each of the branches of physics just named. Maxwell pointed out that this fact constituted strong evidence for the existence of the ether. Now if it does exist, and if it is stationary in space, and // we can determine the absolute motion of the earth with respect to it, then we shall have found our much-desired frame of reference fixed m space. The early experiments seemed to show that the ether is really at rest in space. In 1727 Bradley discovered the aberration of light, and the velocit}'- of light as calculated from his formula agreed well with that found fifty years earlier by Roemer from observations of the eclipses of Jupiter 's satellites. Now since the fact of aberration seems inexplicable on any other basis than a fixed or stationary' ether, be- cause if the ether in the telescope tube travels with it there would be no reason for any aberration, it was considered that the aberration of light clearly indicated that the ether is at rest in space, and that the material composing the earth moves through the ether just as a tennis racquet moves through air, allowing it to flow through the holes in the stringing. But it seemed incredible that any medium could stream 22 Journal op^ the Mitchell Society [September through the interstices in and between molecules in the solid earth at a rate sometimes of more than thirty miles per second without showing the least sign of friction or binding of any kind, and so further experi- ments were made. A\Yy tried the aberration experiment with a tele- scope tube filled with water, and expected to see an increased aberra- tion, because the velocity of light in water is only three-fourths of what it is in air, and according to the aberration formula the less the velocity of light in the telescope tube the greater the angle of aberration should be. But when Airy measured the angle through which the water-slowed light was deflected, he found it exactly the same as Bradley had foiuid for full-speed light! This was a puzzling thing, to be explained only on the theory that the water dragged the ether along with it, with a velocity sufficient to compensate exactly for the change expected in the angle from the diminished velocity of light. Time is wanting to detail the experiments of Fizeau, Fresnel, and others to settle this point, but they showed apparently that something of the kind does take place, — a sort of entrainment or cling or viscous drag of the ether,^ — and they strengthened enormously the conviction that the ether does exist, is a substantial medium, and can be affected by matter, — that is, dragged along. This brings ils to the celebrated experiment of Michelson and ]\Ior- ley, which was an attempt made in 1881, and subsequently repeated, to measure the absolute speed of the earth with respect to the station- ary ether of space. They certainly had a right to expect success, for they took every precaution to ensure it. The experiment consisted in splitting a ray of light, sending one-half in the direction of the earth's motion through space, then reflecting it by a mirror back to the source, while the other half of the yslj is sent at right angles to the line of motion of the earth, and is then similarly reflected back, the two reflected rays interfering to produce interference bands in an inter- ferometer, invented by Michelson. The distance from the source to each mirror is exactly the same, but the distance the light travels to and fro between the mirrors and the source is not the same when the earth is in motion, being greater in the line-of-motion direction than in the direction at right angles to it. The mirrors and other instruments were mounted on a heav.v stone slab floated in mercury, and they expected that when the apparatus was turned through a right angle so that what was before the longer 1920] The Theory of Relativity 23 line-of-motion system became the shorter thwartwise system, they would see the interference fringes in the interferometer move to the right or left. But nothing of the kind happened, and the inevitable conclusion was that there is no appreciable relative motion between the earth and the ether, — -that is, that the earth drags the ether in its vicinity along with it at full earth-velocity! But if so, how can we explain the Airy experiment with the water- filled telescope, where the ether seemed to be dragged with a velocity less than half that of the earth? And especially should be asked, how shall we explain the aberration of light, which seemed to show that the ether isn 't dragged along at all ? Yet undoubtedly the Michelson- Morley experiment seems to indicate that the whole earth is sur- rounded by an envelope of stagnant ether, at rest with respect to the earth. This is absolutely contradictory, and physicists lost no time in making further tests. Lodge spun a huge double disk of steel with tremendous velocity, and sent* a split ray of light around in a groove between the two disks, half in one direction, half in the other. If the discs dragged the ether in the narrow groove around with them, the two half rays, one going with the dragged ether, the other against it, ought to inter- fere and produce fringes. Again no effect. Mascart and others de- vised most beautiful and accurate tests, but all of them gave negative results. ■ In short, as Lodge says : ' ' Interference methods all fail to display any trace of relative motion between earth and ether. ' ' Wood sums it up as follows : ' ' Every experiment, with the exception of the one performed by Michelson and Morley, is in accord with the hypothesis of a stationary ether, ' ' — that is, an ether perfectly station- ary in space. But how then can we explain the negative result of the Michelson- Morley experiment? Certainly interference methods are the most accurate and sensitive we have in the science of optics, and if they fail to detect relative motion between the moving earth and the fixed ether how can we believe that it exists ? Lorentz and Fitzgerald then came independently to the conclusion that a moving piece of matter contracts in the direction of its motion. While this contraction is small, — less than three inches in the case of the earth's diameter in the direction of its orbital motion, — yet it would account exactly for the negative result of the Michelson-Morley experiment, because the longer path of the light parallel to the line of motion of the earth 24 Journal of the Mitchell Society ' [September might, by contraction of the stone slab, become exactly equal to the thwartwise path, and if so, no displacement of the interference frinoes would result. Besides, this contraction is to be expected, anyhow, on the basis of the electron tlieory of matter, and in just the amount nec- essary to explain the negative result of the Michelson-Morley ex- periment. Tests were then made with wood and steel beams, in jilace of the stone slab, and it was found that they apparently contracted in the same manner and to the same extent, so we conclude that all matter behaves in the same way. But if such a contraction takes place in crystals, it looks as though double refraction should take place in them. This was tried b^- Lord Rayleigh and b}' Brace, but again with a negative result. It seemed as though all the forces of nature were in a conspiracy to defeat our efforts to find a fixed frame of reference, and the deter- mination of the absolute vBlocity of the earth with reference thereto, so that after all our work and experimentation it must be admitted that we have but the slightest real idea of either the magnitude or direction of our motion through space, though it would be of the first importance to us in astronomy and physics if we could only know it. Now we come to the Einstein Theory of Relativity, which was at first an attempt simply to explain the negative results of the Michel- son-Morley experiment. We must clearly distinguish three steps or stages in the development of this theory: (1) the Special Relativity theory; (2) the General Relativity theory; and (3) the latter theory as applied to gravitation, or the Einstein Theory of Gravitation. To aid us in understanding the theory of Relativity, let us recall a few of the results attained in the development of Newtonian mechan- ics, on which we have built confidently the entire structure of modern physical science. (Of course the Newtonian mechanics, in its turn, is founded on Euclidean geometry, with its dozen axioms and postu- lates and its three-dimensional space.) In our search for the funda- mental, bedrock conceptions, we have adopted, following the lead of Newton, those of Length, Mass and Time, as separate and distinct ideas, independent of each other, and perhaps capable of absolute measurement. For these we have adopted as our fundamental units the centimeter for length, the gram for mass, and the second for time, giving us the centimeter-gram-second or c.g.s. system of units. We have attempted to base all other ideas, such as force, work, energy, etc., on these as derived ideas, and we call their units derived units. 19W] The Theory of Relativity 25 For example, the notion of velocity implies that a certain length of path is traversed in a certain time, and so by dividing the length by the time we get the rate of motion, which is the derived quantity we call velocity. Hence the dimensional formula, so-called, of velocity, is L/T. In the same way we can express every physical quantity in terras of a dimensional formula involving L, M, and T, except a few which we have been obliged to express partly in quantities just as fundamental as any others, — namely, temperature, magnetic perme- abilitj^ and specific inductive capacity. In addition we have grown accustomed to accept without question Newton's laws of motion, and his inverse square law of gravitation, and we never doubted the unchangeable character of mass. We be- lieved that a quantity of matter had the same mass and inertia under any and all conditions of place, time and velocity. We could change its weight, but not its mass, and this is the law of Conservation of Mass. It is true that in 1881 J. J. Thomson, a rising young physicist, newly appointed head of the Cavendish Laboratory at Cambridge, showed mathematically that an electric charge in motion took on additional mass, but as its velocity had to be very great, — twenty thousand miles per second and upwards, — before this extra mass, or quasi-mass, became appreciable, his work had only a theoretical in- terest, because up to 1897 the highest velocity ever reached by mat- ter, so far as we knew, was that of the great comet of 1882, and that was only four hundred miles per second at the perihelion point of its orbit. In 1897, however, Thomson's theory of the dependence of mass upon velocity suddenly became of the highest interest, because he not only found a way to measure the enormous velocity of flying electrons in a vacuum tube, but also of measuring their charge and their mass, and by developing this method Kaufmann, Bucherer and others proved by measuring the mass of electrons at various speeds that Thomson was quite right in his theory, and that mass does de- pend upon velocity. It follows, therefore, that the mass of a body in the direction of its motion is different from its mass in a transverse direction, and hence arose the idea of longitudinal and transverse mass. Thus a body may have two values of its mass at the same time, — truly a wide departure from the old Newtonian idea. The whole mass of any body at rest is now supposed to be due to the motion and the energy content of its component parts, — elec- 26 Journal of the Mitchell Society [Septei)iher Irons, atoms and molecules, — while if the bod}' itself is in motion an additional mass is given to it in the direction of motion. A shell weighing one ton will have an additional mass of one-millionth of a gram when fired with a muzzle velocity of 2,500 feet per second. For small speeds, therefore, the increase of mass is inappreciable, but for speeds of more than 100,000 miles per second the mass rapidly in- creases until at the velocity of light, which is 186.000 miles per sec- ond, the mass of a body would be infinite. The electrons inside an atom, and the rays fired off from radium, do actually reach prodigious velocities, — more than 100,000 miles per second. But if mass is a function of velocity it is not a fundamental quan- tity, and cannot have an independent existence, so it must be given up as one of the pillars of the temple of science. Now comes Rela- tivity and shows that determinations of both length and time also de- pend upon velocity, so they do not have an independent existence either, and two more pillars of the temple fall, irretrievably', because the determination of absolute velocity is forever beyond our reach. Thus we have our first experience with the realm of Relativity, — the land of Topsyturvydom. "We have our three fundamental concep- tions of Length, Mass and Time all depending upon a derived concep- tion. Velocity, which we formerly held to be dependent upon them ! And then, having pointed this out, the relativist quietly states that all such experiments as that of Michelson and Morley are bound to fail, because it is impossible to determine the absolute velocity of the earth through the ether by experiments made on the earth, and be- sides, there isn't any ether anyhow! To the first statement we reply that we are on the earth, and can't get anywhere else, so if we cannot determine the velocity of the earth by experiments made here we can never know its velocity, and never be able to fix a unit of absolute motion. To which the relativist retorts, ' ' Quite right, — we never can, ' ' and this is the First Postulate of Relativity. To the second statement, that there is no ethereal medium, we can only ask what takes its place, to which the relativist replies, "No medium at all ; electromagnetic energy, including light, is propagated through space somewhat as water is thrown from a hose. It is self- existent, and needs no medium." When we examine this remarkable statement, we should have as the background of our thinking the facts concerning the ether theory, which are, briefly, these: When the as- sumption of the existence of the ether was made, to explain the phe- 1920] The Theory of Relativity 27 nomena of optics, electrostatics, etc., attempts were made to measure its properties. Newton thought its density was something like 700,000 times less than that of water ; Lord Kelvin thought the ether so attenu- ated that it had a density of only one-quintillionth that of water, and many other scientists agreed with them as to the extreme tenuity of the ether. On the other hand, Sir J. J. Thomson says that "all mass is mass of the ether ; all momentum, momentum of the ether ; and all Kinetic energy, kinetic energy of the ether," which shows the confi- dence of the foremost English physicist in the reality of the ether, but he goes on to say that this view "requires the density of the ether to be immensely greater than that of any known substance." Other leading physicists take this view also, and Sir Oliver Lodge insists that the ether has a mass of one quadrillion grams per cubic centi- meter, and that "compared to ether the densest matter, such as lead or gold, is a filmy gossamer structure like a comet 's tail ' ' ! Now we all agree, I am sure, that when Kelvin claimed that one cubic centimeter of the ether weighs one-quintillionth of a gram, and Lodge says it weighs one quadrillion grams, (which is one million tons), there is a serious discrepancy, to say the least, in the estimates of physicists as to the properties of the ether, and we are not sur- prised to learn that there are a multitude of ether theories, — solid, liquid, elastic, labile, irrotational, gyrostatic, adynamic, etc., so no wonder Relativity wants to get rid of the whole thing by turning the ether out of doors. And yet there comes, in protest, the cool reasoning of one of our very foremost American physicists, Millikan, who says that the ether "was called into being solely for the sake of furnishing a carrier for electromagnetic waves, and it obviously stands or falls with the exist- ence of such waves in vacuo, and this has never been questioned by anyone, so far as I am aware." Other leading physicists protest also against giving up the notion of the ether for what Newton called "the forlorn idea" of empty space, among them being Lorentz, the great Dutch mathematician and physicist. But Planck, the originator of the Quantum Theory, gives up the ether, and Einstein of course does the same, for his first postulate implies this very thing. But his second postulate states that light in a vacuum is propagated with a constant velocity quite independent of the velocity of its source, and queerly enough, this postulate seems to assume the existence of the ether, which the first postulate denies. 28 Journal of the Mitchell Society [September or as Stewart says, "we have the Principle of Relativity destroying a concept which is nsed in one of its postulates," — another instance of Topsyturv.ydom. Einstein admits this, but cannot get away from the confidence he, and all other physicists, have always had in Maxwell's great theory of electrodynamics, and the equations in which it is expressed, and so Einstein states in his London "Times" article that for this reason he was led to achieve the logical reconciliation of his two postulates b}- making a change in the doctrine of the physical laws of time and space. In doing so, however, he was obliged to overthrow some of the time-honored ideas of Galileo and Newton, and deal wath four-dimen- sional, instead of three-dimensional space. Of course that also meant using non-Euclidean mathematics, and the difficulties pressing upon him from every side seemed nisuperable. But he was immensely helped by the work of Minkowski, who developed a system of four dimensions, — using time for the fourth dimension, — involving four rectangular axes, of which three are for the three space dimensions, and the fourth is the time axis. Space and time are thus bound to- gether, and no mathematical difference is made between them, the axes being interchangeable. It is of course impossible for us to conceive of four dimensions all at right angles to each other, but let us take this example : When we go to the moving-picture show, we see the screen picture in only two dimensions, of course. But we supply a third dimension in our minds by seeing the perspective of the picture. We see a horseman coming in the distance apparently straight towards us, along the third axis wdiich our mind supplies perpendicular to the screen. But there is another element in the picture, the time element. Time is always of the essence in melodrama. The interest centers in the question as to whether the hero, beset with difficulties and dangers, as he always is, will be in time to rescue the fair heroine. This time element, measured along an imaginary time axis, is also mentally present, and the picture is not complete without it. And moreover, as stated before, while we cannot visualize this axis at right angles to the others, the mathematician can make his equations behave exactly as though we could. What Tennyson calls our "bourne of time and place," therefore, Minkowski calls a four-dimensional "space-time continuum," and by using four-dimensional geometrv he showed Jww events in nature may j.^20] The Theory of Kelativity 29 he represented mathematically, and how any equation referred to these four axes could be transformed to any other set of axes provided the second set is at rest or moving uniformly with respect to the first. Einstein used many of Minkowski's ideas, and developed what he calls his Special Relativity Theory, which he describes as follows : The Special Relativity theory is the application to any natural process of the following- propositions : 1. Every law of nature which holds good with respect to a co- ordinate system K must also hold good for any other system K' pro- vided that K and K' are in uniform motion of translation. 2. The second proposition is that light has a constant velocity in a vacuum, quite independent of the velocity of its source. There is much experimental evidence for the truth of this second postulate, and the special theory, resting only on the two postulates just given, was eagerly studied by physicists. It was immediately seen that the most important fields of study were those of acceleration and energy. The conception that inert mass is nothing but latent energy was developed, the law of conservation of mass lost its independence and became merged with the law of conservation of energy, and new laws of motion, differing from New- ton's, were worked out for masses moving with great velocity. Many startling and unexpected results were found, and Einstein pushed his investigations vigorously. Please remember that his special theory dealt only with axes in uniform motion, and he next tried to find a more generalized theory dealing with axes in any kind of motion. Again the obstacles in his path seemed to defy his highest skill. But he persisted, for he asked himself, whj^ must the independence of physical laws with regard to a system of co-ordinates be limited to a system of co-ordinates in uniform motion of translation with regard to one another? What has Nature to do with the co-ordinate systems which we propose, or with their motions? "We must, of course, use arbitrarily chosen systems to describe Nature's operations, but they ought not to be limited as to their state of motion. So he worked on until he found the necessary transformation formulae for any hind of motion of the axes, and_this is what he calls his General Theory of Relativity, the single postulate of which may be stated as follows : The laws of nature must remain invariant for all transformations of co-ordinates. But he further says that "a generalized theory of 30 Journal of the Mitchell Society [September Relativity must include the laws of gravitation, and actual pursuit of the conception has justified the hope." So his third achievement -is his new theory of gravitation, which diflfers widely in some respects from that of Newton. To understand it is not easy. First, let me remind you that gravitation has always been a phys- ical mystery, and numerous theories to account for it have been de- veloped without success. For one thing the speed of gravitation seems to be infinite, the only thing in nature which has a speed greater than light. Again, we say the sun "attracts" the earth and holds it in its orbit, but when we find that this so-called attraction is a force sufficient to break a million millon rods of the best tensile steel, each seventeen feet in diameter, we are amazed that any ethereal medium can transmit it. And if we let the ether go, we are still more perplexed. Let us, however, start with the conception that all pulls are really pushes. When lemonade is sucked or pulled through a straw, it is really the pressure of the atmosphere which pushes it through the straw from the other end. Perhaps gravitation is a push, rather than a pull. When a baseball curves, we do not imagine something pulling it around in a curve, but we think of the bank of air in front and on the side of it, due to its twisting motion, as pushing it around. In like manner a railroad train is pushed by the reaction of the outer rail around the curve in the track. So we may imagine gravitation as pushing the earth around in its curved orbit. From this conception let us proceed to another, — the principle of Least Action. It may be familiarly expressed in this way ; every moving body holds to the line of least resistance. That is what the curving baseball does; per- haps that is what the curving earth does. If so, the first thing to ascertain is what the line of least resistance is in space, and why it is so, if we can ; at any rate, find out what a body will do, and how it will move under certain conditions. This Einstein has done, and as he worked he came more and more to the conclusion that the idea of gravitation, like the ideas of time and space, is only part of the mental scaffolding we have erected to explain the phenomena of nature, and has no existence apart from our brains. To understand this let us imagine ourselves in an elevator high up in the Woolworth building. We 'feel the weight of our bodies pressing the soles of our feet ; we feel the weight of the package we are carrying; perhaps a pendulum is swinging in the elevator. Then i£i^OJ The Theory of Relativity 31 suppose the wire rope breaks ; the elevator v^^ith its contents falls ver- tically with the gravitational acceleration of thirty-two feet per sec- ond per second. If we could keep our mental equilibrium under the circum- stances, we would notice that our weight appeared to vanish ; that the package we carried also lost its weight, and if we removed our hand from it, it would remain suspended in mid-air ; the pendulum, if at the end of its swing when the rope broke, would remain there motion- less and would not swing back. In other words, so far as we are concerned, and so long as the elevator is falling, gravity has been anni- hilated by giving the appropriate acceleration to the elevator. In reality, an observer inside a closed windowless box could not by any means decide whether the box is in a static gravitational field, or is endowed with accelerated motion in a space free from gravitation. We seem to weigh more while in an elevator ascending with acceler- ated motion, so that acceleration simulates gravitation and may be substituted for it. Now imagine two sets of four-dimensional axes, one set stationarj^ in the Woolworth building, and the other set fixed in the falling elevator. Let x, y, z, and t be the co-ordinates of a point with reference to the second, or falling-elevator set of axes. Then, since we have no gravitation in the elevator to complicate matters, an element of length ds with reference to this set would be given by the equation fls- =: dx- + cly' + dz= + dt- Now let the same point mentioned above have at the same instant the co-ordinates x', y', z' and t' with reference to the first, or fixed-in- the-building set of axes. Then the transformation equation for ds will be d8^ — g„dx'2 + g^dj'' + g,,dz" + g44clt'- + 2g,A x'dy' -f 2g,,dx 'dz' + etc. There are ten of these g coefficients, and their value depend? on ihe nature of the transformation, and specifies it. They can be used, therefore, not only to specify it, but they also define the original grav- itational field, because they specify how it was got rid of. Now in Einstein's theory these ten gr's, used in ten differential equations, are regarded as ten values of the gravitational potential specifying the field, and one of them, g^^, is approximately the same as the Newtonian potential, except for a factor. 32 Journal of the Mitchell Society ISrpfcDihrr Einstein, after long investigation, has so chosen his equations that they remain unaltered by any change of co-ordinates, and these ten are the only ones which do satisfy all conditions. What has just been said illustrates Einstein's famous "Principle of Equivalence," which states that for any particle at any instant it is possible to replace the effect of a gravitational field upon it by a mathematical transforma- tion of axes. If, therefore, gravitation can be annihilated mathematically by a transformation to an accelerated set of axes, and if its very existence depends upon a choice of axes, which is contrary to the General Rela- tivity Postulate, then gravitation, in the words of deSitter, "becomes almost a property of space." Of course a first approximation from Einstein's (■({nations, neg- lecting terms of higher orders, gives the old Newtonian law for com- paratively small velocities. Please notice, however, that Einstein's theory only shows how gravitation acts, not what causes it to act thus. It is in no sense an explanation of gravitation, which remains as much of a mystery as before. Now a new theory, like a tree, is known by its fruits, and when Einstein was asked to make his theory do things to prove its truth he was at first perplexed to find cases in which the actual differences between his theory and that of Newton could be subjected to observation. But he was not long at a loss, and presented three eases which would test the correctness of his theory. The first case was the long outstanding discrepancy between theoiy and observation shown in the displacement of the perihelion point of Mercury's orbit. This point shifts around toward the east at the rate of 574 seconds of arc per century. The Newtonian mechanics, allowing for the effect of the other planets on Mercury's orbit, accounts for a shift of only 532 seconds, thus leaving an unexplained shift of 42 seconds of arc per century. Einstein's theory calls for a difference of 43 seconds, — an almost startling agreement. But of course Einstein might have started with this answer, and worked backwards, as it were, to his equations, so a great deal more interest was taken in his second case : a prediction that at the eclipse of the sun on May 29, 1917, the light of certain stars which just grazed the sun on its way to the earth would be found to have a deviation from a straight path because of the sun's gravita- tional field which he estimated would amount to 1.75 seconds of arc. l.'J;^0\ The Theory of Relativity 33 This prediction was made in 1917, two years before the eclipse, and Einstein was a professor in a German university, shut in by the war, and so helpless to test the observation himself, but the English promptly began to make plans for sending out not one but two eclipse expeditions to test the theory. Let us examine the point in question. For years it has been customary to regard light as having mass, for we reasoned as follows : Light is a form of energy ; being of the kinetic type it is expressed mathematically in terms of its velocity and its mass, or at least something that takes the place of mass and acts like it. Now if light possesses mass and velocity it must possess momentum, and ought to exert a push when it falls on a body. This light pressure, or radiation pressure, was predicted by Maxwell, and its value calculated by him, but it was only experimentally confirmed forty years later by Nichols and Hull and Lebedew. It is the radia- tion pressure from the sun which causes a comet 's tail to stream behind the comet when approaching the sun, and to stream ahead of the comet when receding from the sun. The question next arises, does light possess weight? Is the mass of light the kind which is acted on by gravitation? If so, we can consider a beam of light passing near the sun as a comet, and using the regular comet formula we can regard the speed of light as the speed of the comet, and as usual insert the proper value of nearest approach to the sun. From this formula we can find the angle be- tween the asymptotes of the cometary orbit, and hence find the angle of deviation of the ray which we should expect on the basis of New- tonian mechanics. The result is an angle of .82 seconds of arc. Now in the case of ordinary comets we have always found that their speed increases while they are approaching the sun, and decreases after they have swung round it on their long journey back into the depths of space, so Newton's idea was that this acceleration should be expected of any comet moving with any speed, and acted on by the sun's gravi- tation, because force always produces acceleration in a mass free to move. And just here is one of the most interesting of Einstein's dis- coveries. It is shown from his formulas that if a body is approaching the sun with a velocity less than about 100,000 miles a second, it will be accelerated in its motion, but if it has a velocity greater than this amount it will actually he retarded as it moves toward the sun. Such a thing is inconceivable on the basis of Newtonian mechanics. Incon- 34 Journal op^ the jMitciiei.l Society [September cc'ivable, yes, Imt is it true? Einstein worked out his predicted devia- tion of a ray of light grazing the sun on the idea that it is true, — that the ray does reall}- suffer a retardation on its way toward the sun proportional to the increasing gravitational field of the sun. This would of course make the part of the wave front closest to the sun move more slowly than the remoter portion, and hence the ray would be swung round through an angle of 1.75 seconds of arc, as already mentioned, and this is more than twice the angle expected from Newton's laws. So here is a clear-cut test; — Newton or Ein- stein,— a deviation of .82 seconds of arc, or a deviation of 1.75 sec- onds. Wliich would it be? The two British eclipse expeditions sent out last summer, one to Sobral, in Brazil, and the other to Prince's Island, west coast of Africa, both detected the deviation, and in the required amount to show the correctness of Einstein's views. This was the triumph which put Einstein's name on the front page of every newspaper, and made every physicist in the world prick up his mental ears and begin to study Einstein's work more closely. The third test set by Einstein for his theory was this: — his formu- las show that the inside mechanism of an atom moves more slowly in a gravitational field than in free space. Perhaps this is due to the retardation suffered by a particle moving with a prodigious velocity through a gravitational field, as considered above. At any rate, Einstein predicted that light waves coming from a source located in an intense gravitational field would make a spectrum in which the lines would be shifted toward the longer-wave end of the spectrum, which is the red end. This effect was looked for without success, lint Einstein remained serene in his conviction that it would be found, and offered to rest the validity of his entire theory upon it. Now comes his third triumph, for quite recently two young physi- cists at Bonn not only detected the shift towards the red end of the spectrum, but also discovered the reasons why previous attemi)ts to find it, at Mt. Wilson and elsewhere, were unsuccessful. These three triumphant verifications of the Einstein ideas about gravitation" have focussed the eyes of the world upon this modest scholar in Berlin. Born a German Jew, he moved to Switzerland during his boyhood, was educated there, became a Swiss citizen and served for some years in the Swiss patent office. During this time he pursued his mathematical studies, and later taught in the Zurich Poly- 1,920] The Theory of Relativity 35 technikiim, from which he went to the University of Prague. Just before the war he was called to the University of Berlin, at the age of forty. He did not sympathize with the militarists and pro- tested vehemently against the famous, or rather infamous, manifesto of the German professors in 1915. His frank statement expressing his thanks to the English government and to his ''English colleagues" for going to so much trouble and expense to verify his predictions, when he was himself helpless to do so, shows a fine spirit, and has gained for him both admiration and respect. It was, in part, as follows : "It was in accordance with the high and proud tradition of English science that English scientific men should have given their time and labor, and that English institutions should have provided the material means, to test a theory that had been completed and published in the country of their enemies in the midst of war." Some of the more mathematical and theoretical conclusions drawn from his equations may be interesting. If a circle be imagined in empty space, its circumference bears to its diameter the usual ratio of 3.14159 to 1, but if a heavj^ mass be placed at its center, the ratio of circumference to diameter is changed, because of a ''warp in space" produced by the mass. Again, suppose a wheel is rotating in space. The rim of the wheel, because it is at every point moving in the direc- tion of its length, suifers the contraction already explained in connec- tion with the Michelson-Morley experiment, but the. spokes of the wheel are not moving in the direction of their length, and hence do not suffer contraction. Here again the circumference of the wheel changes length while the diameter does not, so the ratio is again not the usual one. This same contraction in the direction of motion is suffered by electrical, optical and gravitational fields. If a system is moving with respect to us, the unit of time in the moving system seems longer to us than to an observer on that system, and when the system is moving with respect to ours with the velocity of light, their second would seem infinitely long to us. That is, if we could watch a clock face on a system receding from us with the velocity of light, although an observer on the system with the clock would see it running as usual, we would forever see the clock hand at exactly the same point. This sounds as crazj' as anything in "Alice in Wonderland," and in fact the Mad Hatter must have been the originator of Relativity, and to have had this very point in mind when he claimed that for 36 Journal of the Mitchell Society [Septcmher him it was always six o'clock and always tea-time. Einstein goes even farther than this; let me quote his own words: ''We could sub- stitute for the clock a living organism enclosed in a box. Were it hurled through space like the clock it would be possible for the organ- ism, after a flight of whatever distance, to return to its starting point practically unchanged, while an exactly similar organism which re- mained motionless at the starting point might have given place to new generations. For the organism in motion, time was but a moment, if its speed approached the velocity of light." This statement implies that not only does time depend on velocity, but that the rapidity of chemical and biological processes is also a function of velocity. Rosalind's remark is therefore doubly true, that "Time travels in divers paces with divers persons," and until the velocity of each system is known (that is, the relative velocity, for we can never find the absolute velocity of any system,) we cannot know with whom the swift foot of Time ambles, trots, gallops, or even stands still withal. One observer's now may be another observer's future and a third observer's past, all at the some cosmical moment of time. Two actions quite simultaneous to one observer may not be simultaneous to another observer located in a different system. Again, what to a stationary observer is an electrostatic field is to a moving observer an electromagnetic field. According to Einstein and Minkowski any point relatively at rest in space really traces a "world-line" or "path of adventure" parallel to the time axis. The locus of a point in relative motion is a line mak- ing an angle with the time axis. An observation is the crossing of two or more world-lines, and we know nothing of these world-lines between the points of crossing with other world-lines. The axes of our four-dimensional space-time continuum have been aptly called the to-and-fro axis, the forward-and-backward axis, the up-and-down axis and the sooner-and-later axis, the last, of course, being the time axis. On one side of the origin the time axis represents the past, on the other side the future. Events do not happen, — they are coinci- dences of world-lines, and are simply there, to be met or happened upon, as it were. A few years ago Anderson's new star burst forth. Whatever caused it is supposed to have occurred about the year of George Washington's birth, but we only happened upon a crossing of its world-lines with ours one hundred and seventy years later. If a change is made in an element of our sj'stem, it alters the whole past, 19::0] TiiE Theop.y of Relativity 37 mathematically speaking, as well as the future. This seems absurd, and corresponds to nothing real in our experience, so far as we know, but these equations we are discussing have proved true in so many ways that we eagerly anticipate their further interpretation. New tests for straightness of lines, for simultaneity of events, etc., have been adopted, and everything seems queer and unfamiliar. Straight lines, according to Relativity, appear crooked to us, and vice versa. Spheres in motion become oblate spheroids, and we feel like the prisoner in Gilbert and Sullivan's opera, condemned always to play on a warped table, "on a cloth untrue, with a twisted cue, and elliptical billiard balls." According to this theory, also, the greatest possible velocity in space is that of light, — 186,000 miles per second. Even if a shell were fired with a velocity of 100,000 miles per second directly for- ward from a gun mounted on a car moving with the same velocity of 100,000 miles per second, the resultant velocity of the shell would not be 200,000 miles per second, as we should expect, but only 150,000. No combination of any number of velocities impressed upon a body can exceed the velocity of light. The new definitions of physical terms are equally puzzling, as for example: "Matter does not cause the curvature of space, — it is the curvature." Again, Einstein has prac- tically ignored in his theory the idea of force as the condition for change of motion, which was possibly the greatest contribution made by Galileo to the science of dj-namics, and in spite of the fact that some physicists hold force to be perhaps the most basic of all the ideas of mechanics. As already said, the ether, which Planck calls a "child of sorrow," is, in the eyes of relativists, hopelessl}^ discredited. The work of Einstein is epoch-making. Just as for sixty years everything in physics has had to square with Maxwell's equations, — even Einstein's theory, — so now there is already seen a tendency to make our thinking square with Einstein's equations. Just what results will come out of the new theory it is impossible to say. The Einstein mechanics have shown at least some power of exploration of intra- atomic space, which Newtonian mechanics could not do, and this may assist us in the development of a rational theory of atomic structure better than any theory we now have. But we are not to stop here. The English are actively preparing to make even more accurate observations in Australia during the 38 Journal of^ the ^Iitchei.l Society [Septcmhrr eclipse of 21st September, 1922, when we may liope to have miu-h additional light thrown upon the whole subject, wliieh now presents, it must be confessed, many difficulties. For example, according to the new quantum theor}^ energy is radiated in a discontinuous fasliion in very small amounts called quanta. The value of a quantum lias been determined, but according to the Relativity theory, since it trav- els with the speed of light, every quantum should a|)i)eai- infinite, which it doesn't. Then, too, by no means all physicists agree with the tlieory, and Abraham, for instance, has opposed it vigorously, warning us against the ''Sirenenklaenge dieser Theorie." Many others, such as Sir Jo- seph Larmor, Avhile not hostile, are lukewarm. T ronton says that Rela- tivity is merely trying to remove the lion in the path by laying down the general proposition that the existence of lions is an impossibility. The truth is that the theory is so new, so revolutionary, and so difficult to understand, that the natural conservatism of science forces it to make its way slowly. Then, too, the language in which it is expressed in the articles scattered through the literature of the subject is not easily "understanded of the people." As an example, Larmor complains in one of his articles that a certain expression is only "wrapping up in abstractions the simple statement that when at any place the quadratic characteristic of the spatial extension in- volves the differential of the co-ordinate specially related to time in its product terms, then there is latent in it a specification of its own mode of change at that place with respect to uniform space-time."' You see what a "simple statement" in non-Euclidean Relativity sounds like, and this may throw light on Einstein's reported saying that he did not suppose there were more than twelve men on the earth at present who can understand his theory fully. The surprising thing about this statement is that he should have put the inimb<'r so high as twelve. In conclusion, let us sum up the situation: I'onservatives in sci- ence claim that at best Einstein has merely introduced some refine- ments in our mathematical weapons of attack; but the radicals claim that he has overthrowMi much of the older mechanics, has given the coup de grace to the ether, and has started an entirely new chapter in the development of human thought comparable onl.v to tluit beg\ni by Galileo and Newton ; furthermore, tliat the Relativity i)oint of 1920] The Theory of Relativity 39 view will color everything in the future, and that we have now two and only two foundations on which we can build with confidence, — the Electromagnetic Theory of Clerk Maxwell and the General Relativity Theory of Albert Einstein. Chapel Hill, N. C. A PAETIAL LI8T OF BOOKS AND ARTICLES CONSULTED Physical Optics. 2d. Edition. R. W. Wood, Chapters 24 and 25. The Progress of Physics. A. Schuster. Electrons. Oliver Lodge. History of the Theories of Aether and Electricity. E. T. Whittaker. : Aether and Matter. J. Larmor. Chapter 2, Appendix D. Electricity and Matter. J. J. Thomson. The Ether of Space. O. Lodge. , Modern Electrical Theory. 2d Edition. N. R. Campbell The Electron. R. A. Millikan. Resume of Observations Concerning the Solar Eclipse of May 29, 1919, and the Einstein Effect. L. A. Bauer, Science, March 26, 1920. Euclid, Newton and Einstein. "W. G. ", Nature, Feb. 12, 1920. The Theory of Relativity. A. C. D. Crommelin, Nature, Feb. 12, 1920. Einstein's Theory of Gravitation. E. Cunningham, Nature, Dee. 4, Dec. 11, and Dec. 18, 1919. The Recent Eclipse Results, and the Stokes Planck Ether. L. Silberstein, Phil. Mag., February, 1920. Gravitational Deflection of High-Speed Particles. Leigh Page. Nature, Feb. 26, 1920. The Ether vs. Relativity. Oliver Lodge. Fortnightly Review, January, 1920. Gravitation and Light. J. Larmor. Nature, Dec. 25, 1919, and Jan. 22, 1920. A New Conception of the Universe. A. J. Lotka. Harper 's Mag., Feb., 1920. Time, Space and Gravitation. A. Einstein. Educational Review, Feb. 1920. Gravitation and the Principle of Relativity. A. S. Eddington. Nature, Dee. 28, 1916. Elementarquantum der Energie. J. Stark. Physik. Zeitsehr., Dec. 1, 1907. Relativity in Astronomy. W. C. Rufus. Popular Astronomy, March, 1918. Zur Elektrodynamik bewegter Koerper. A. Einstein. Ann. der Physik, 17, 1905, p. 891. Relativitaet und Gravitation. A. Einstein. Ann. der Phys., 38, 1912, p. 1059. Lichtgeschwindigkeit und Statik des Gravitationsfeldes. A. Einstein. Ann. der Phys., .38, 1912, p. 355. 40 Journal of the Mitchell Society [September Raum und Zeit. H. Minkowski. Phy. Zeitschr., 10, 1909. The Principle of Relativity. E. Cunningham. Nature, June 11 and 18, 1914. The Second Postulate of the Tlieory of Relativity. Q. Majorana. Phys. Rev., May, 1918. Relativity. A. 8. Eddington. Nature, March 7 and 14, 1918. Presidential Address, Section A, British Association, 1914. F. T. Trouton, Nature, August 20, 1914. Einstein's Theory of Relativity. Morris R. Cohen. New Republic, .j.-iiiuary 21 and February 18, 1920. Applications of the Lorentz-FitzGerald Hypothesis to Dynamical and Gravita- tional Problems. H. A. Bumstead. Am. Jour. Sci., 26, 1908. Relativity. D. F. Comstock. Science, May 20, 1910. On the Theory of Relativity. R. D. Carmichael. Phys. Rev., Sept., 1912; Feb. and March, 1913. The Second Postulate of Relativity and the Electromagnetic Emission Theory of Light. R. C. Tolman. Phys. Rev., 32. 1911, p. 148. The Second Postulate of Relativity. R. C. Tolman. Phys. Rev., 31, 1910, p. 26. On the Essence of Physical Relativity. J. Larmor. Sci. Am. Supp., No. 2253. Relation of Mass to Energy. D. F. Comstock. Phil. Mag., 15, 1908, p. 1. Fundamental Laws of Matter and Electricity. G. N. Lewis, Phil. Mag., 16, 1908, p. 705. New Concepts of Time and Space. Claude Bragdon. Dial, Feb., 1920. Acht Voi-lesungen ueber Theoretische Physik. Max Planck, 1909. Relativitaet und Gravitation. M. Abraham. Ann. der Phys., 38, 1912, p. 1056. Relativity and Ether. Leigh Page. Ann. Jour. Sci., Aug., 1914. Aether and Matter. Oliver Lodge. Nature, Sept. 4 and Sept. 25, 1919. Physical Relativity. G. W. deTunzelmann. Sci. Am. Suppl., May 31, 1919. Einstein's Law of Gravitation. J. S. Ames. Science, March 12, 1920. Results of the Total Solar Eclipse of May 29. A. C. D. Crommelin. Nature, Nov. 13, 1919. Relativity and Gravitation. O. Lodge and A. S. Eddington. Nature, Sept. 13, 1917. Einstein's Third Victory. R. D. Carmichael. N. Y. Times, March 28, 1920. Gravitational Deflection of High Speed Particles. A. S. Eddington. Nature, March 11, 1920. Gravitational Shift of Spectral Lines. H. Jeffreys. Nature, March 11, 1920. The New Relativity in Physics. R. A. Wetzel. Science, Oct. 3, 1913. Attitude of the Newer Physics toward the Mechanical View of Nature. G. B. Pegram. Ed. Rev., March, 1911. 1920 \ The Theory of Relativity 41 The Theory of Eelativity. L. T. M. Nation, Apr. 11, 1912. The Principal Concepts of Physics. W. F. Magie. Science, Feb. 23, 1912. The Principle of Equivalence and the Notion of Force. C. A. Kichardson. Nature, March 18, 1920. A NEW METHOD FOR LAYING OUT CIRCULAR CURVES BY DEFLECTIONS FROM THE P. I. By T. F. HiCKERSON With Three Text Figures The writer hopes that the tables based upon formulas given be- low will fill the long-felt need of a simple and time-saving method for laying out circular curves by deflections from the point of inter- section of the tangents (the P. I.), thus avoiding the trouble of moving the instrument and resetting the vernier. Referring to Fig. 1, P is any point on the circular arc CB and A is the point of intersection of the tangents. Also C is the point of curve (P. C), and B is the point of tangent (P. T.). Lines from points A and 0 to point P makes angles of 0 and o. with the line AO, these angles being plus when measured above AO and minus when below it. PN is drawn perpendicular to AO. The deflection angle is called A. PN R siu a R sin a Ton e = — = AN E + E — R t-os a R (sec V^ A — 1) -|- R — R cos a sin a Hence, tan 6 = (1). see y-2 A — cos a Formula (1) shows that for a given value of A^ the angle 0 is independent of the radius of the curve or the length of curve. Imagine the curve divided into ten equal parts, then formula (1) gives the deflections to these points of division as follows : sin ti 0 A a = tio A, tan 91 = — a = •)i() A . tan 9^ :=: a = ri 0 A , tan 9 ;, = a =z '',](i A , tan 9 < = sec y. A — cos lioA a = (). 9 , =: O , a = — iioA, 9 „ = — e,, ^ = — -;ioA, 9 , = — 9:., a = — %oA, 9 , = — 9„ a = — Mo A, 9 ,, = — 9,, a =3 — s^ioA, 9,„ = — i/,(18() — A). [ 42 ] see i/^A — cos sin %oA MoA' sec 1^ A — cos sin 710 A %oA sec 14 A — cos 71 0 A sin li 0 A 1920] New Method for Laying Out Circular Curves 43 Values of 0^, 0.,, 0.,, etc., computed by means of the above for- mulas for different values of A show that they change uniformhj with A ; so that interpolation gives results as closely as 1 minute for ranges of 1° in A. PT/B IP \sf tx Fig. 1 For convenience in laying out curves without resetting the vernier, these directions to points on the curve are referred to the first tangent, the line CA produced. Instrument at the P. I., and vernier reading A° on the P. T., we have : 44 Journal of the Mitchell Society [September — e, = 90° + y^A — Gi. Deflection to point ( 1) = A + %(18C ) — - A ( 2) = 90° + 1/2 A — 62, ( 3) =: 90° + i/>A — Q., ( 4) =z 90° + i/l>A — ©4, ( 5) ^ 90° + i/,A ( 6) m 90° + y2A + 0 4, ( 7) = 90° 4- ¥2 A + 0 3, ( 8) = 90° + ¥2 A + 0 2, ( 9) = 90° + ¥2 A + e., (10) ^= 180' 0 It should be noted that the following pairs of deflections add up to 180° + A°; (1) + (9), (2)'+ (8), (3) + (7) and (4) + (6). Using the above formulas, tables have been computed for all values of the deflection angle A varying by 1° from 3° to 128°. This covers all cases that are likely to occur in locating curves for roads and streets. Fig. 2 is a graphical verification of the fact that for a fixed A, the deflections to the points of equal division on a curve remain con- stant for any length of the curve. This makes the method perfectly general. The order of procedure in laj'ing out a curve is as follows : ( 1 ) set up the instrument at the P. I., backsight on the first tangent witii vernier reading 0°, transit the telescope, unclamp the vernier and fix the line of sight on the second tangent, the vernier giving the de- flection angle A°; (2) decide what length of curve to use (deter- mined usually either by the desired external distance E or the tan- gent length T) ; (3) compute T and E, using either the well-known table of tangents and externals for a 1° curve, or preferably the tan- gents and externals for a 100-ft. curve (Table II) ; (4) lay ofl^ the tangent length locating the end of the curve (the P. T.) ; (5) di- vide the length of curve by 10 and locate each of the ten points, or every other one, or every third one, etc., depending upon how many are needed to properly define the curve, by starting at the P. T., and getting the intersection of the end of the chord with the line of sight from the P. I., according to deflections read directly from the tables (Table I). The middle point, or the 5th point of the curve, cannot be located very precisely by intersections, since the end of the chord would be moved in an arc tangent to the line of sight. This point can be lo- cated exactly by measuring the external distance E from the P. I., and this serves as a check. If only the 2d, 4th, 6th, 8th, and 10th points are located, then it is not necessary to know E. 1920' New Method for Laying Out Circular Curves 45 VI v / / \ //'/ / // / / I \ \ \ . I \ \ \ \ \\ /^/ ^7 I \^ /^c.A '7 I 4-\ ,fPT .A \/ PC. '^ \pr Oy^S '>*V*''' ,PT Fig. 2 The beginning of the curve (the P. C.) is located as the 10th point by a deflection which is always 180°. The station number of the P. C. is known, hence its location can be checked by measuring 46 Journal op the Mitchell Society [Sepfeniher the plus distance back to the preceding station. This method avoids measuring the tangent distance from the P. I., in order to locate the P. C. It should be noted that the curve can be located b.y starting at the P. C. instead of the P. T., the deflection to the first point being the same as that to the 9th jioint as given by Table 1, etc. If part of the curve is not visible from the P. I., say that beyond point 6, then the instrument may be moved to point 6 and the reaiain- ing points located by deflections from a preceding chord. Suppose a backsight is taken to point 2, vernier reading 0°, then after reversing ' 5A° A<» the telescope the proper deflection to locate point 7 is = — , etc. 2 X 10 4 For very long curves in woods and at places where the P. I. is not accessible, the well-known deflection method should be used, that is, the instrument is moved to the P. C, and intermediate points on the curve. During the past summer the writer was in charge of a party that surveyed 22 miles of federal-aid highways in hilly and mountainous country, and the following facts were observed: (1) not a single case of inaccessible P. I. occurred; (2) along 86 per cent of the curves the P. I. was visible throughout; (3) in only 42 per cent of the curves was the P. T. visible from the P. C. This means that 86 per cent of the curves could have been laid out completely with the instrument set only once (at the P. I.), whereas 58 per cent of them actually re- quired the instrument to ])e set up three times. The first 11 miles was in fairly open country along the general direction of an old road. Here 96 per cent of the curves were visible throughout from the P. I., but 70 per cent of the P. T. points were not visible from the P. C. The other 11 miles of the survey was partly in a dense forest and not along an old road. Aside from the time saved in not having to move the instrument, another step in the usual operation of laying out a curve is avoided, and that is, the tangent distance is not measured from the P. I., in order to locate the P. C. Curves laid out by the usual method begin and end with subchords of unequal length. This makes the deflections rather tedious to compute. The errors are eunuilative, and tlie writer has seen the best of transitmen waste time in trying to find the little error that prevented the final check. 19:^0] New Metpiod for Laying Out Circular Curves 47 The resident engineer can more easily pick np the P. I., than any other point and he would find it convenient to realign the curve by deflections from this position while construction is going on, since it is apt to be beyond the grade stakes and not disturbed. The points on the curve established by deflections according to the proposed new method are at equal and integral distances apart, but they are not full stations. The writer believes the advantages of full station points are largely imaginative. However, the chain- men can easily locate full station points on their return trip from the P. C. to the P. T., as is explained in Example 1. The middle or- dinate of the equal chords can be found in Table III which has been compiled by the writer for the purpose. In this connection, it should be remembered that middle ordinates vary practically as the square of the chords ; and for any chord, the ordinates vary practically as those of a parabola. See Fig. 3. Thus if the middle ordinate is 1 ft. the ordi- nate (or offset) at a point 2/5th of the chord-length from the end of the chord is 0.6 ft. The middle ordinate in practice is usually less than 1 ft. as will be seen later. Before proceeding with an illustration, Table II will be explained. This table gives the Externals, Tangents, Radii, and Degrees of Curve for circular Arcs of 100 feet in length according to values of the deflec- tion angle ranging from 1° to 128°. It is offered as a substitute for the tables giving the functions of a 1° curve. The following formulas were used in computing the values in Table II : 100 A 100 A D = L 100 5729.578 5729.578 T = E tan V., A = tan i/> A , A 5729.578 E = K tan M.. A = exsec i/,A, 48 Journal of the Mitchell Society [Scptemher For curves longer than 100 feet, the tabular values of the external, tangent, and radius must be multiplied, and the degree of curve di- vided, bj^ the ratio of the given curve length to 100. For example, suppose A is 24° and the length of curve to be used is 400 feet, then 24 E = 5.334 X 4 = 21.3, T = 50.744 X 4 = 203.0, D = — = 6°, 4 R = 238.8 X 4 = 955.2. This tables gives conveniently a length of curve that will always be a multiple of ten. The chords therefore will always be an integral number of feet in length. Exatnple 1. Given A = 40°00'; P. I at Sta. 62 + 11.8 From Table II, L = 100, E = 9.193, T = 52.135, D = 40°. Suppose local conditions are such that E should equal 4G feet 46 approximately. Hence, ratio = — = 5. 9.2 L = 500, E = 46.0, T = 260.7, D = S°. 500 = 50 == length of each chord to be applied 10 times. 10 P. I. = 62 + 11.8 T. = 2 + 60.7 P. C. = 59 + 51.1 L. = 5 P. T. = 64 + 51.1 For A ^z= 40°00', the deflections are given directly in Table I as follows : Points Deflections P. T. A 1st 40° 29' 2d 42°29' 3d 47°58' 4th 63°41' 5th (E -= 46.0) n0°00' 6th 156°19' 7th 172°02' 8th 177°31' 9th 179°31' 10th P. C. 180°00' 1930] New Method for Laying Out Circular Curves ■19 As a check in taking deflections from the table, it should be noted that the 1st + 9th = 2d J- 8th == 3d-f 7th ^ 4th -f 6th = 180 + A = 220°00'. The above points on the curve are not at full stations ; but the chainmen, on their way back from the P. C, can very easily set stakes at full station and -(- 50 foot points as follows : the rear chainman holds the -\- 51.1 division of the tape at the P. C, and aligns the front chainman by sighting to the 9th point of the curve ; then a right angle offset on the P. I. side of the curve, at a certain fraction (see Fig. 3) of the middle ordinate for a chord of 50 feet (see Table III), locates Sta. 60 (in this case the middle ordinate is 0.44 ft. and the offset is less than 0.1 ft.) ; next the rear chainman holds the zero end of the tape at Sta. 60 and aligns the front chainman by sighting from the 9th point to the 8tli point, in order to locate Sta. 60 -f- 50 which is so near the 8th point it does not have to be shifted. The other stations are established in a similar manner. Example 2. Given A = 20^20' ; P. I. at Sta. 37 + 18.2. T = 50.532, E ^ 4.5 (Table II). Suppose T = 100 = approx. desired length of tangent. Eatio = 2, hence L = 200, T = 101.0, D = 10°10'. P. I. = 37 + 18.2 T = 1 + 01.0 P. C. = 36 + 17. L = 2 P. T. = 38 + 17.2 200 := 20. Use 40-ft. chords applied five times. 10 Points Deflections P. T. A° 2d 21°40' 4th 35° 13' 6th 165°07' 8th 178°40' 10th P. C. 180°00' 2d + Sth = 4th + 6th = 200°20'. Check. The quantities in Tables II and III are based on the definition that the "degree of curve" is the central angle subtended by an arc of 100 feet instead of a chord of 100 feet. The radius of a one- degree curve is found by means of the following proportion : 36000 36000 1° : 360° =: 100 feet : 2f;R feet, hence R = = = 5729.578 feet. 2(3.14159) 50 Journal of the Mitchell Society [September The middle ordinate (M) of an are whose central angle is a° and whose chord is c feet, is given by the formula : M = R vers i/oa (4). c" Also M ^= approx (5). 8 R Formula (5) shows that for any radius, the middle ordinates vary as the square of the chords. The above formulas were used in com- puting Table III. Assuming the arc to be parabolic, we ha-ve a convenient relation between ordinates at any point along the chord and the middle ordi- nate. See Fig. 3. For example, an ordinate at 8/10 of the chord- length from one end of the chord is 6/10 of the middle ordinate. In practice, the middle ordinate is usually less than 1.0 foot, pro- vided the chords do not exceed the limit where they vary more than .05 ft. from the arc. Table III shows these limits to be as follows : 100 ft. chords up to 6° curves 50 ft. " " lt3° " 40 ft. " " 25° " 30 ft. " " 37° " 25 ft. " " 47° " 20 ft. " " 67° " 15 ft. " " 100° " middle ordinates uj) to 1.31 ft. ' 0.S7 ft ' 0.87 ft ' 0.72 ft ' 0.64 ft ' 0.58 ft ' 0.49 ft 1920 New Method for Laying Out Circular Curves 51 TABLE I. )cfleetion.s from the P. I. to Points of Equal Division along Circular Curves. ooc' rH O Q O Q Q O + + + + + 1 111 s-i r- d d cci d CO d d ^ d 53^ O O r^ -* IC ^ rH O O r Q an i 111^ - ilo rH i-H iC IM O COO-*-* O CO Cl 1-H i-i CS CO ':0 GO 35 O 1-1 r-l W CO Oi Ol:^l>-t^ 00 i-H T-H r-l i-l rH II 0 <1«M as. rH CO I^ ih O LO i^ CO ^ O OOOJ'sO lO CO-!— 1-1< CO i—t-^OOOi o (M oi CO Tfi o cor^t-i^ CO 5"^ rH CD F-f t* O t- rH O rH O OONSD lO O tr-OiC: O i-H i-H r-t C^ Oi COt^t*I> 00 II COCOCOCO O t*'*-^-*' o Ho rH(M-*iO O OrHCO-f O aj\ O O (M I>- ift Ir- (N O O O ph" r-I r-i r^ O* ooJ-co d c^deq^H d O "^ -^ r-t O ■* fH iH U3 O (M (M -** 1-H O 0t-0505 O rHF-'f-'C-l Ci t*f*t^t* 00 ocic-ii-i o oicci-'tn o I— II—'T^-l' O 1— tCO-^-T o CU 0^ 1 52 Journal of the ]\Iitchell Society [Septemher TABLE 11. Externals, Tangents, Radii and Degrees of Curve to a 100 Ft. Circular Arc. Diff. 10' Diff. 10' Defl. per Ft. r 0.218 .036 50.001 .001 5730 1° 0.3' "2° 0.436 .036 50.005 .001 2865 2° 0.6' 3- 0.655 .036 50.012 .001 1910 3° 0.9' 4° 0.873 .036 50.020 .002 1432 4° 1.2' 5° 1.092 .036 50.032 .002 1146 5° 1.5' 6° 1.310 .036 50.046 .003 955.0 6° 1.8' 7° 1.530 .036 50.062 .003 818.6 7° 2.1' S° 1.749 .036 50.081 .004 716.2 8° 2.4' 9° 1.969 .036 50.103 .004 636.6 9° 2.7' 10° 2.189 .036 50.127 .005 573.0 10° 3.0' 11° 2.409 .037 50.155 .005 520.9 11° 3.3' • 12° 2.630 .037 50.184 .005 477.5 12° 3.6' 1.3° 2.851 .037 50.216 .006 440.8 13° 3.9' 14° 3.073 .037 50.251 .006 409.3 14° 4.2' 15° 3.296 .037 50.288 .007 3S2.0 15° 4.5' 16° 3.519 .037 .50.328 .007 358.1 16° 4.8' 17° 3.743 .037 50.370 .008 .3,37.0 17° 5.1' 18° 3.968 .037 50.416 .008 318.3 18° 5.4' 19° 4.193 .038 50.463 .009 301.6 19° 5.7' 20° 4.419 .038 50.514 .009 286.5 20° 6.0' 21° 4.646 .038 50.567 .010 272.9 21° 6.3' 22° 4.875 .038 50.624 .010 260.4 22° 6.6' 23° 5.104 .038 50.6S3 .010 249.1 23° 6.9' 24° 5.334 .039 50.744 .011 238.8 24° 7.2' 25° 5.565 .039 50.809 .011 229.2 25° 7.5' 26° 5.797 .039 50.876 .012 220.4 26° 7.8' 27° 6.030 .039 50.9t6 .012 212.2 27° 8.1' 28° 6.264 .039 51.020 .013 204.6 28° 8.4' 29° 6.500 • .040 51.096 .013 197.6 29° 8.7' 30° 6.737 .040 51.175 .014 191.0 30° 9.0' ,31° 6.976 .040 51.257 .014 184.8 31° 9.3' 32° 7.216 .040 51.342 .015 179.1 32° 9.6' 33° 7.457 .040 51.430 .015 173.6 33° 9.9' 34° 7.700 .041 51.521 .016 168.5 34° 10.2' 35° 7.944 .041 51.615 .016 163.7 35° 10.5' 36° 8.190 .041 51.712 .017 159.2 36° 10.8' 37° 8.438 .042 51.813 .017 154.9 37° 11.1'- 38° S.68S .042 51.917 .018 150.8 38° 11.4' .39° 8.939 .042 52.024 .019 146.9 39° 11.7' 40° 9.193 .043 52.135 .019 143.2 40° 12.0' 41° 9.448 .043 52.249 .020 139.8 41° 12.3' 42° 9.706 .043 52.366 .020 136.4 42° 12.6' 43° 9.965 .044 52.487 .021 1.33.3 43° 12.9' 44° 10.227 .044 52.611 .021 130.2 44° 13.2' 45° 10.491 .044 52.739 .022 127.3 45° 13.5' 40° 10.757 .045 52.871 .023 124.6 46° 13.8' 47° 11.025 .045 53.006 .023 121.9 47° 14.1' 48° 11.296 .046 53.145 .024 119.4 48° 14.4' 49° 11.570 .046 53.288 .025 117.0 49° 14.7' 50° 11.846 .047 53.435 .025 114.6 50° 15.0' 51° 12.125 .047 53.586 .026 112.3 51° 15.3' 52° 12.407 .047 53.740 .027 110.2 52° 15.6' 53° 12.691 .048 53.899 .027 108.1 53° 15.9' 54° 12.979 .049 54.062 .028 106.1 54° 16.2' 55° 13.270 .050 54.230 .029 104.1 55° 16.5' 56° 13.564 .050 54.402 .029 102.1 56° 16.8' 57° 13.861 .050 54.577 .030 100.5 57° 17.1' 58° 14.161 .051 54.758 .031 98.79 58° 17.4' 59° 14.465 .051 54.943 .032 97.11 59° 17.7' 60° 14.773 .052 55.133 .033 95.49 60° 18.0' 61° 15.084 .053 55.328 .033 93.93 61° 18..3' 62° 15.399 .053 55.527 .034 92.41 62° 18.6' 63° 15.718 .054 55.732 .035 90.95 63° 18.9' 64° 16.041 .055 55.941 .036 89.52 64° 19.2' 1920] New Method for Laying Out Circular Curves 53 TABLE HI. MIOTLF. OROINATFS CHORDS Deg. Radius Curve For Chords of For Arcs of 100 Ft. 80 PL 60 Ft. 50 Ft. 40 Ft. 100 Ft. SOFt. 60 Ft. 50Ft.40Ft. 1- 5730 0.2 0.1 0.1 0.0 0.0 100 80 60 50 40 2° 2865 0.4 0.3 0.2 0.1 0.1 100 80 60 50 40 3° 1910 0.6 0.4 0.2 0.2 0.1 100 80 60 50 40 i" 1432 0.9 0.6 0.3 0.2 0.1 100 80 60 50 40 5° 1146 1.1 0.7 0.4 0.3 0.2 100 80 60 50 40 6° 955.0 1.3 0.8 0.5 0.3 0.2 100 80 eo 50 40 7° 818.6 1.5 1.0 0.6 0.4 0.3 99.94 80 60 50 40 8° 716.2 1.8 1.1 0.6 0.4 0.3 99.92 80 60 50 40 9° 636.6 2.0 1.2 0.7 0.5 0.3 99.90 79.95 60 50 40 10" 573.0 2.2 1.4 0.8 0.5 0.3 _99.88_ J79.93_ 60 50 40 For Chords of For Arcs of 520.9 SOFt. 60Ft. SOFi. 40Ft. 30Ft. SOFt. ~79.92~ eOFi. 50 Ft. 40 Ft. SOFt. 11° 1.5 0.9 0.6 0.4 2 60 50 40 30 12° 477.5 1.7 0.9 0.7 0.4 .2 79.91 60 50 40 30 13° 440.8 1.8 1.0 0.7 0.4 .2 79.89 60 50 40 30 U° 409.3 2.0 1.1 0.8 0.5 3 79.87 59.95 50 40 30 15° 382.0 2.1 1.2 0.8 0.5 3 79.85 59.94 50 40 30 16° 358.1 2.2 1.3 0.9 0.6 .3 79.83 59.93 49.95 40 30 17° 337.0 2.4 1.3 0.9 0.6 .3 79.81 _59^92 49.95 40_ 30 For Chords of For/ Ires of 318.3 60 Ft. 50 Ft 40 Ft 30 Ft. 25 Ft. 60 Ft. 50 Ft. 4)?l. SOFl. 25Fi 18° 1.4~ 1.0 "0.6^ 0.3 0.2 ~5979r" 49.94 ~40 ~30~25" 19° 301.6 1.5 1.0 0.7 0.4 0.3 59.90 49.94 40 30 25 20° 286.5 1.6 1.1 0.7 0.4 0.3 59.89 49.94 40 30 25 21° 272.9 1.7 1.1 0.7 0.4 0.3 59.88' 49.93 40 30 25 22° 260.4 1.7 1.2 0.8 0.4 0.3 59.87 49.93 40 30 25 23° 249.1 1.8 1.3 0.8 0.5 0.3 59.84 49.91 40 30 25 24° 238.8 1.9 1.3 0.8 0.5 0.3 59.84 49.91 40 30 25 25° 229.2 2.0 1.4 0.9 0.5 0.3 59.82 49.90 39.95 30 2.1 26° 220.4 2.0 1.4 0.9 0.5 0.3 59.81 49.90 39.95 30 25 27° 212.2 2.1 1.5 0.9 0.5 0.4 59.79 49.89 39.94 30 25 28° 204.6 2.2 1.5 1.0 0.5 0.4 59.78 49.88 39.94 30 25 29° 197.6 2.3 1.6 1.0 0.6 0.4 59.77 49.87 39.93 30 25 30° 191.0 2.3 1.6 1.0 0.6 0.4 59.76 49.87 39.93 30 25 31° 184.8 2.4 1.7 1.1 0.6 0.4 59.74 49.85 39.92 30 . 25 32° 179.1 2.5_ 1.7 1.1 0.6 0.4 59.73 49.84 39.92 _30 25 For Chords if Fi r Arcs of 173.6 SOFt. SOFt. 25 Ft. 20 Ft. 10 Ft. 50 Ft. SOFt. 25 Ft. 20 Ft. 10 Ft. 33° 1.8 0.6 0.4 0.3 0.1 ^49783" 30 25 ""20" ~10" 34° 168.5 1.8 0.7 0.5 0.3 0.1 49.82 30 25 20 10 35° 163.7 1.9 0.7 0.5 0.3 0.1 49.81 30 25 20 10 36° 159.2 2.0 0.7 0.5 0.3 0.1 49.80 30 25 20 10 37° 154.9 2.0 0.7 0.5 0.3 0.1 49.79 29.95 25 20 10 ■ 38° 150.8 2.1 0.7 0.5 0.3 0.1 49.78 29.95 25 20 10 39° 146.9 2.1 0.8 0.5 0.3 0.1 49.77 29.95 25 20 10 40° 143.2 2.2 0.8 0.5 0.3 0.1 49.75 29.94 25 20 10 41° 139.8 2.2 0.8 0.6 0.4 0.1 49.74 29.94 25 20 10 42°- 136.4 2.3 0.8 0.6 0.4 0.1 49.73 29.94 25 20 10 43° 133.3 2.3 0.8 0.6 0.4 0.1 49.71 29.93 25 20 10 44° 130.2 2.4 0.9 0.6 0.4 0.1 49.69 29.93 25 20 10 45° 127.3 2.4 0.9 0.6 0.4 0.1 49.67 29.92 25 20 10 46° 124.6 2.5 0.9 0.6 0.4 0.1 49.65 29.92 25 20 10 47° 121.9 2.6 0.9 0.6 0.4 0.1 49.63 29.92 24.95 20 10 48° 119.4 2.6 0.9 0.6 0.4 0.1 49.62 29.92 24.95 20 in 49° 117.0 2.7 1.0 0.7 0.4 0.1 49.60 29.91 24.95 20 10 50° 114.0 2.7 1.0 0.7 0.4 0.1 49.59 29.91 24.94 20 10 Note — Tables I, II and III complete for values of A up to 128° in convenient form for use in tlie field may be obtaiiit d from the author at a price of 25 cents per copy. A REMARKABLE FORM OF SKELETAL ELEMENT IN THE LITHISTID SPONGES (A Case of Analogical Resemblance) By H. V. Wilson With Four Text Figures Sponges, like other groups, are rich in the structural resemblances which are due to common descent, resemblances which involve nu- merous organs in the individual animal and wliich are of such a com- plex intricate character, striking so deeply into the constitutional make-up, that it is impossible to think of them as due to any natural cause save kinship. But as we stud}' these infinitely variable animals, we encounter resemblances which fall in another category, resem- blances which involve only some special detail of structure or at most a few features, which in their actual functioning are correlated in physiological-mechanical function. Such resemblances are certainly, in many cases at least, not inheritances from a common ancestor. "We group them together as analogical but they fall in two subdivisions : (1) those involving features which are called out in each individual organism by the stimulus of an environment, and which do not appear when that environment is changed; and (2) those involving features which are racial characteristics, viz., characteristics that have arisen and become fixed, in some way, during the course of evolution and which continue to appear under different sets of environmental con- ditions. Analogical resemblances of this latter class are due to the inde- pendent occurrence of the same variation (or cumulative series of variations), in different idioplasms. How such germinal changes, mutations as we often call them, are brought about physiologically, is a question that is being actively asked by many students of heredity, especially by the experimental evolutionists, of today. Along with the directly experimental attacks, descriptive work has its use in locating facts which at some time it may be worth while to put under the fire of experiment. Partly, at least, in pursuance of this idea I wish to record a case of resemblance which is certainly analogical, and which, it is practi- cally certain, is racial. It involves the shape of the fundamental spicule on which the characteristic skeletal element, the desma, of the lithistid sponges is built up. I 54 I 1920] Skeletal Element in Lithistid Sponges 55 The clesma is a silicious body, in most species of a complexly branched shape (Figs. 3, 4), formed by the continued deposition of silicious material on a silicious spicule which we may call the basic spicule, technically crepis (Fig. 1). The basic spicules, which are especially present in growing parts of the sponge, are free bodies, that is, they lie in the living tissues of the sponge unconnected with one another or with other skeletal elements. The desmas on the con- trary as they assume the final shape, become articulated with one an- other, and in most species become firmly united to form a coherent skeleton which presents the appearance of a network of silicious beams. Now the basic spicule of the desma is in some lithistida a four- rayed spicule (tetraxial or tetractinellid spicule), in others a simple rod-shaped spicule (monaxial). Different as are the basic spicules in these two groups of species, the complete desmas are not always easy to distinguish, for in both cases they may become complexly branched bodies. This superficial similarity of the two kinds of desmas, those built on tetraxial, and those built on monaxial spicules, is in itself significant, but when we find, as we do in some species, desmas of the latter class varying toward desmas of the former class, it becomes clear that the desma built on a four-rayed spicule (tetracrepid desma) is the original or ancestral type, while the desma built on a monaxial spicule (monocrepid desma) is a derived type. These in- teresting and important variations were first described by 0. Schmidt in Discodermia clavatella (0. Schmidt, 1879, pp. 12, 24). Sollas (1888, p. 341) confirmed the facts and convinced himself "that a com- plete series of transitional forms connect the monocrepid and the tetra- crepid desmas." Topsent (1904, p. 60) has discovered the same state of affairs in another lithistid sponge, Macandrewia azorica. The four-rayed shape may thus be regarded as the original, actual or ancestral, shape of the spicule which is transformed by the depo- sition of silicious matter into the desma. This spicule in the case of tetracrepid desmas in general is what is called a calthrops, viz., a spicule in which the four rays are similar, making the same angle with one another and having the same length. But in at least one species, Desmanthus incrustans Topsent, an evolutionary change has occurred, whereby one of the rays of the basic spicule has become longer than the others, the spicule thus being converted from a calthrops into a triaene. In the triaene, a very common form of spic- ule in the non-lithistid tetraxial sponges, we distinguish, then, one 56 Journal of the Mitchell Society [Septemher long ray, the shaft (technically rhabdome), and three shorter rays (the cladi, forming together the cladonie), which are given off from the end of the shaft. In the sponge which I shall now describe, a further evolutionary change has occurred, and rays are given off at both ends of the shaft of the basic spicule, the spicule thus becoming what is called an amjihitriaene (Fig. 1). The sponge referred to is a Philippine form, a new species, Jere- opsis fruticosa mihi, dredged by the U. S. Fisheries Steamer Albatross in 80 fathoms in the region of the Sulu Archipelago, and which will be described in detail in a forthcoming report on Philippine sponges. It is a stony sponge of branching-cylindrical, or shrubby, habitus, 55 mm. high, and with the free spicules of the genus (dichotriaenes, oxeas, and streptasters including amphiasters and spirasters). In the two other recorded species of the genus, Jereopsis schmidtii (Sol- las) from the tropical Atlantic and Jereopsis {Neosiphonia) superstes (Sollas) from the tropical Pacific (cf. Sollas 1888, Lendenfeld 1903), the desma is, perhaps, the usual type of tetracrepid desma, built up on a calthrops. Schmidt's figure (1879, Taf. II, Fig. 10) suggests however that this is not the case. I hope at some time to have the opportunity of making a critical examination of the desma, from this point of view, in the type specimens of these two species. The facts concerning the development and structure of the desma in this sponge {Jereopsis fruticosa) are as follows: Small, perfectly free amphitriaenes (Fig. 1) occur in the super- ficial (ectosomal) region of the sponge. The spicules are about one- sixth mm. long, and consist of a straight shaft with three rays (cladi) at each end. The streak of peculiar substance, known as the "axial canal," which is found in each of the axes of a tetraxial spicule, here extends, as the figure shows, along the axis of the shaft and to the tip of each ray. Early stages in the transformation of such spicules into desmas may be found near the surface of the sponge. One is shown in figure 2. Such young desmas are free or only slightly connected with the body of the skeleton. In them the shaft continues to be of about the same length as in the basic spicule (Fig. 1), although it is thicker, but the rays have greatly increased in length. They measure now from one-half to the full length of the shaft or indeed slightly over. They are simple, viz., not branched, and when not corroded their ends bear rounded tubercles for articulation with other desmas. The axial 1920] Skeletal Element in Lithistid Sponges 57 substance, "axial canal", retains its former size (cf. Figs. 1, 2), thus extending only into the basal part of each ray. This is the character- istic behavior of the axial canal in the growth of the lithistid desma in general. As such desmas develop their final shape, they become firmly united to the skeletal framework already formed. If one wishes to stud}' accurateh' their fundamental shape after union, the spicules must be isolated through the application of hydrofluoric acid to rough slices of the framework. When the framework is so treated the desmas fall apart. They are however corroded. Figs. 1-4. Jereopsis fruticosa. Fig. 1, a free and uneorroded amphitriaene from the ectosome. Fig. 2, a young desma, slightly corroded by hydrofluoric acid, from the ectosome. Figs. 3 and 4, adult desmas somewhat corroded by the hydrofluoric acid used to dissociate them from the skeletal framework. All x 150. Desmas (Figs. 3, 4) obtained in this way show the unchanged axial canal system which indicates the shape of the basic spicule on which the desma has been built up. The shaft is now about three times as thick as in the original spicule but no longer. The rays, better designated now as branches (technically cladi), vary a great deal not only in different spicules but in the same spicule. In some cases they have not advanced over the condition described for the inter- mediate stage (Fig. 2), either in size or complexity. More often, the branch is itself branched, a condition which is produced, of course, not 58 Journal of the Mitchell Society [September by the division of the first branch but by the continued deposition of silicions matter along lines which make angles with the first branch. In this way secondary or even tertiary branches are formed. There is apjoarently some law of growth which brings it about that no branch shall materially exceed the shaft in length. When or before that point is reached, new branches are formed. The articular tu- bercles are developed on the ends of the branches, whether the latter be primary, secondary, or tertiary. In many cases, as in Fig. 2, where the branches are about equally developed at the two ends of the shaft, the axial canal system of the basic amphitriaene is conspicuous, but it may be overlooked in cases where, as in Fig. 4, the branches at one end of the shaft are much more extensively developed than at the other end. The point of importance for this paper is that the basic spicule, on which the adult desma is built, is an amphitriaene, that is a spicule consisting of a shaft and three rays at each end of the shaft. I can find no similar case recorded for the Lithistida. In the non-lithistid tetraxial sponges, amphitriaenes are recorded only for Samus Gray and Amphitethya Lendenfeld (1906). Samu.s (one species) is a boring sponge occurring in the South Atlantic, Indian, and South Pacific Oceans. The only megascleres are amphi- trianes, which are not all alike. In the larger of these spicules, the shaft, 80/A long, bears at each end three rays, each of which is trifid. In the smaller ones, the shaft, 20jii long, bears at one end three simple rays, and at the other end three trifid rays. While the sponge falls in the Sigmataphora because of its microscleres, which are sigmata (rods curved somewhat in c-shape, but with a spiral twist), its pecu- liar megascleres give it an isolated position, setting it off as a family (Samidae). The ontogeny of the amphitriaenes is not known, and we have no data on their variation to indicate their origin. It is highly probable however that the spicules have been derived from triaenes, although Sollas (1888, p. 59) has suggested two other con- ceivable origins. In Amphitethya (Lendenfeld 1906, p. 126) there is no doubt that the amphitriaenes, which characterize the genus, are derivatives of the triaene. In Amphitethya microsigma Lendenfeld, a stalked species with globular body dredged off the west coast of Australia, the facts of variation which demonstrate this are as follows. Triaenes of sev- eral kinds occur abundantly in the sponge, those in the more axial 1920] SKELf:TAL Element in Lithistid Sponges 59 part of the stalk having an especially long shaft, as is often the case in such sponges. In the superficial part of the stalk there are abun- dant triaenes with short shaft, and mingled with these are the likewise abundant amphitriaenes. The latter spicules, in which the length of the shaft is 160-540ft, are exceedingly variable, scarcely two alike, and they form a close series grading over from amphitriaenes, quite like the spicules I have described above, to the short-shafted triaenes. These observations of the late Professor Lendenfeld securely establish the origin of the amphitriaene. Amphitriaenes were already known in the two other species of the genus, Amphitethya stipitata (Carter) and in the sponge from Amboina designated by Topsent Tetilla mer- guiensis Carter (Topsent 1897, p. 437). In the former Sollas noted (1888, p. 49) that ''the amphitriaenes sometimes are reduced to simple triaenes." In the latter, the detailed facts, such as similar- ities in size and precise shape, convinced Topsent that the amphi- triaenes are modified triaenes. Amphitethya is a genus with sigmata, and thus falls in the Sigmatophora. There is still another non-lithistid tetraxonid sponge in which at least a step has been made toward the transformation of the triaene into the amphitriaene. This is Ancorella paulini Lendenfeld (Len- denfeld 1906, p. 248) from the Indian Ocean. The spicules referred to consist of a shaft, one millimetre or less in length, which bears at one end three cladi, projecting slightly downward as in an anatriaene, and at the other end a similar single cladus, extending out from the shaft at an angle in the same general direction as the cladi at the op- posite end. The sponge is classed in the Astrophora by Lendenfeld, who regards its microscleres (microxeas) as derived from streptasters. It may be regarded as certain that the presence of the amphitriaene in these several cases is not due to inheritance. The distance of the sponges from one another in the classification, expressing their general dissimilarity, negatives this idea. The comparison of Amphitethya with Jereopsis is especially instructive. Each has plenty of close rela- tives without amphitriaenes, and the two sponges fall in different suborders of the Tetraxonida. To be sure the Lithistida may not be a natural suborder but a polyphyletic group, some members of which have been derived from non-lithistid tetraxonia with astrose ■ microscleres (Astrophora), and others from non-lithistid tetraxonida with sigmata for microscleres (Sigmatophora). Even in this case 60 Journal of the Mitchell Society [September Jereopsis would be related to the Astrophora, Ainpliitetliya to the Sigmatophora.' The only conclusion that is possible is tiiat tlie triaene has varied and become an amphitriaene, independently, in several groups. The resemblance is analogical, one of ' convergent evolution ', a rubric under which we group likenesses that are due to similar responses on the part of related, but not necessarily closely related (witness the simi- larities between the hydro- and scyphomedusae), organisms to the en- vironment. We classify it, then, as due to a heritable change that may occur in triaenes independently of inheritance, that is, reversion plays no part in its appearance. We would like to know how to evoke it. If this and similar cases _in the sponges should ever be approached experimentally, through the alteration of the external or internal en- vironment, the series of known spicule forms connecting perfect amphi- triaenes with perfect triaenes, in Aniphitethya )nicrosig))ia, Avould lead us to expect that the change induced would be more or less cumu- lative. Also our general knowledge of variation in sponge spicules (cf. Wilson 1904, pp. 9-10) would lead us to expect that the herita])le change would probably at first affect comparatively few spicules. That analogical similarities are common in sponges is generaly rec- ognized, although there is not much that is definite in our knowledge. Nowhere is more emphasis laid on their occurrence than in 0. Schmidt's writings. As illustrating Schmidt's standpoint, the following cita- '^ The remarkable cliaracter of the lithistiil desma makes a strong argument for the inonophyletic origin of the group, weakened in no degree by the fact that some desmas are built on four-rayed, others on rod-shaped, basic spicule.s. For (see above) the variation 1 henomena in several species show that the latter kind of basic spicule is reducible to the former. Sollas (1888, p. CXIX) has laid weight on this argument for the monoiihyletic origin of the group, which lie derives from the Astrophora. The derivation from the Astrophora in particular is based on the fact that the most frequently-occurring type of microsclere in the Lithistida is astrose. The fairly numerous Lithistida without microscleres offer no difficulty to this theory, for comparative study shows that microscleres have been independently lost during the evolution of various sponges. But the few forms with sigmata (Scleritoderma, Taprobane) do offer a difficulty, if we continue to lay such stress, as now, on differences in the matter of microscleres. The whole question (cf. Dendy 1905, p. 99) can only be raised, but not answered until our critical knowledge is much greater. Alternative hypotheses may be formulated as follows: (1) We may assume a monoi>hyletic origin of the group and trace it back along with the Astrophora and Sigma- tophora to Tetraxonida with both kinds of microscleres, asters and sigmata, in which case it would certainly be astonishing that the two kinds of microscleres had mutually repelled one another during the evolution of the Astrophora and Sigmatophora, and again within the Lithistida during the evolution of the existing families. (2) If we assume first the evolution of the Astrophora and Sigmatophora from Tetraxonida with both kinds of micro scleres, and then the origin of the Lithistida from the former, it is at least conceivable, as Sollas has noted (Inc. cit. p. CXX) that the occurrence of sigmata in some Lithistida is a case of reversion. J'ollowing out this idea, the reversion to sigmata might concoivably occur in Lithistids that had lost their microscleres. If we assume it to have occurred in forms with microscleres (asters), tlien again we meet tlie strange conclusion that sigmata and asters repel one another, tlie reversional variation which brings back sigmata driving out the asters. (3) If we lay stress in the first degree on the difference in microscleres, we are driven to conclude that" the Lithistida have had a double origin, some from the Astro- phora, some from the Sigmatophora, and that the habit of forming a complex body, the desma. on a free basic spicule, has been twice acquired. Doubtless the number of liypothe- ses that are logically sustainable, might be increased. J. 920] Skeletal Element in Lithistid Sponges 61 tions from his "Sponges of the Gulf of Mexico" (1879) may be made. ''In the Sponge-fauna of the Atlantic Region, I have shown what a great role within the sponges is played by the phenomenon of conver- gence in the production of pseudo-homologies. These fall- under the general concept of adaptations in so far as one is justified in speaking of adaptations to general mechanical laws" {loc. cit., p. 4). Schmidt goes on to say that his entire criticism of characters, in the work of comparing organisms with one another, aims at distinguishing what is the result of inheritance and what the effect of the environment, the latter "only drawn into the stock of hereditary characters in the course of a gradual process of fixation" (an abstract statement into which more than one meaning may be read). He continues and notes that in most contributions of the time, especially those dealing with embryology, the possibility that morphological agreement is not always based on common descent and heredity, is far too lightly passed over (a habit of mind which the progress of physiological-mechanical studies has greatly changed since Schmidt's time). Chapel Hill, N. 0. LITEEATUEE CITED Dendy, a. 1905. Eeport on the sponges collected by Prof. Herdman, at Ceylon, in 1902. In : Herdman Eep. Pearl Oyster Fisheries, Part III, London. Lendenfeld, E. von. 1903. Das Tierreich, 19 Lieferung. Tetraxonia. Berlin. 1906. Wissenschaftliche Ergebnisse der deutschen Tiefsee-Expedition, Bd. XI. Die Tetraxonia. Jena. Schmidt, O. 1879. Die Spongien des Meerbusen von Mexico (und des Carai- bischen Meeres). Erstes Heft. Jena. Sollas, W. J. 1888. Eeport on the Tetractinellida collected by H. M. S. Chal- lenger. Edinburgh. ToPSENT, E. 1897. Spongiaires de la Bale d 'Amboine. Eevue Suisse de zoologie, t. IV. Topsent, E. 1904. Spongiaires des Acores. Eesultats des eampagnes scien- tifiques accomplies sur son yacht par Albert ler Prince Souverain de Monaco. Ease. XXV. Monaco. Wilson, H. V. 1904. Eeports on an exploration off the west coasts of Mexico, Central and South America, etc. The Sponges, Memoirs Mus. Comp. Zoology, Vol. XXX, THE TURTLES OF NORTH CAROLINA; WITH A KEY TO THE TURTLES OF THE EASTERN UNITED STATES By C. S. Brimley The animals known as tortoises, turtles or terrapins, no one of which names by the way has an exact application to any particular group of the order, are distinguished from all other living reptiles by having the body enclosed in a bony shell, leaving only the head, neck and limbs free. This shell consists of two portions, an upper more or less arched portion known as the carapace and a lower, smaller, flattened part known as the plastron. These two are united on each side by a bony bridge or cartilaginous suture. The majority of existing turtles have the shell covered with horny plates, which do not agree, either in size, number or position with the bony plates beneath (though on the carapace the general arrangement of both is similar), but in two small groups the shell is covered with a leathery skin instead. The classification of turtles seems somewhat unsettled, but we can distinguish without much trouble a few main groups, whatever may be their exact relation to one another. 1. Athecae. Marine turtles with the shell composed of a mosaic of small hexagonal plates which are free from the ribs and vertebrae, and covered with a leathery black skin, and with seven longitudinal ridges down the back. This group includes only the leatherback turtles, the largest of all existing forms. 2. Thecaphora. In which the shell is composed of a number of bony plates, agreeing in number with and attached to or composed of the expanded ribs and upper processes of the vertebrae. These are attached to a row of marginal bony plates forming the edge of the shell, and these at the sides to another series of plates forming the plastron. The Thecaphora comprise the majority of existing turtles and di- vide into : (A) The soft-shelled turtles (Trionj'choidea) in which the shell is flattened, orbicular and imperfectly ossified around the edges, and covered with a leathery skin. The species occur in most parts of the world. [ 62 ] 1920] Turtles of North Carolina 63 (B) The side-necked turtles (Pleurodira) in which the shell is covered with horny plates and the neck bends sideways (in a hori- zontal plane) when drawn back. The species are all south tropical. (C) The S-necked turtles (Cryptodira) in which the shell is covered with horny plates and the neck bends in a vertical plane when drawn back. The majority of existing turtles belong here, in- cluding all the marine species except the leatherbacks. All of these groups except the Pleurodira are represented in this State or off our coasts, so that at present the turtles are known to be represented in our State by four marine and fourteen inland species. Of the marine turtles, which, however they may differ in struc- ture, all agree in having the limbs developed as flattened paddles for swimming and in having the front limbs much larger than the hind ones, we get the leatherback, green turtle, loggerhead and bastard turtle. The leatherback is only occasional on our coast, but one caught near Beaufort ^is now preserved as a mounted specimen in the State Museum at Raleigh and weighed about 800 pounds. The species is sometimes used as a source of oil. The green turtle used to be common on our coast but has been hunted so much for food, and its eggs collected for the same reason that it is now very scarce. The loggerhead and bastard turtle are still quite common in sum- mer and the former breeds but the latter does not, its breeding season being reported to be in the winter on the Florida coast. These marine species all feed on both marine plants and animals. Of the land and fresh water forms we get species belonging to three families, while members of a fourth, the Trionychidae or soft- shelled turtles should enter our State from either the south or west or both, but as yet we have no satisfactory records of them. The three families referred to above are the Chelydridae or snap- ping turtles with a narrow cross-shaped plastron, large head and long tail ; the Kinostermidae, or mud turtles, in which the plastron has ten or eleven plates and is divided into three parts, a fixed middle portion and a front and hind portion, both of the latter, or at least the front part being capable of being moved so as to partially close the shell, and the Testudinidae or terrapins, in which the plastron has twelve plates and is either wholly fixed or divided into only two portions, which are movable on a central hinge. 64 Journal of the Mitchell Society \Srptrinhrr Only one species of snapping turtle occurs in our State, and this usually goes simplj- by the name of "turtle," all our other species being known as terrapins in this State. The snapper is the largest and the ugliest of our species reaching a weight of 25 pounds, and is also the one most frequently locally eaten, being in fact quite palatable. It is a voracious and vicious reptile, wholly carnivorous, and capable of inflicting a painful wound if carelessly handled. Its eggs are white, soft-shelled and spherical. The second family includes two of our species, which much re- semble the snapping turtles in habits, but differ in the broad plastron and smaller size, neither reaching a length of more than about four inches in the shell. The mud turtle has the head unstriped, and the plastron nearly as large as the shell opening, wiiile the musk turtle has the head with yellow stripes and the plastron considerably smaller than the shell opening. The latter is more of a deep water animal, the former more of a shallow water form, preferring to hunt for its prey with its shell half in, half out of the water. The eggs are elongated, hard-shelled and white. The balance of our turtles belong to the Testudinidae and all ex- cept one are aquatic and have wholly tixed plastrons. The exception is the Box Turtle, commonly called Highland Terra- pin in this State, which is mainly an inhabitant of damp woods, though I have found specimens buried in the wet mud of a swamp in a place where in a wet season they would have been fifty yards from shore. The short high arched shell and the moveable plastron which closes the shell completely when the animal has withdrawn its head and limbs within, distinguishes this from all our other species. Its food consists of fruit, succulent leaves of plants, and living or dead animals of any kind it can capture. The remainder of our species differ but little in habits, all being acpiatic inhabitants of pools and streams seldom leaving the water except to deposit their eggs, which are elongate and soft-shelled. Roughly speaking, they divide into two groups, the smaller pond turtles with a smooth shell without variegated markings, and the larger terrapins, collectively often known as river terrapins, yellow- bellies, sliders or cooters, which have the shell almost invariably wrin- kled or keeled or both. The former rarely attain a length of over five inches, the latter are from eight inches to a foot or more long when adult. 19.C0] Turtles of North Carolina 65 The small pond terrapins inclnde onl.y three of onr species, the speckled terrapin in which the head and shell are marked with round, yellow dots, the mountain terrapin with the yellow markings confined to a yellowish patch on each side of the head just behind the eye, and finally the painted turtle in which the shell has red markings around the edges of the shell. The latter is the larger, attaining a length of five inches when adult, the other two not reaching more than four. The first and last are present in the greater part of our State, the raiountain terrapin, in or near the mountain region only. Of the larger terrapins we get five species of sliders proper, the long-necked chicken turtle and the diamond-back terrapin, the last being a salt marsh species. The sliders are the largest of the group, some of them attaining a length of over a foot in the shell and a weight of ten pounds. The various species inhabit ponds and large streams and are most plentiful in the Mississippi Valley and the southeastern States. I cannot say much as to the habits of this group, but of the two species which formerly constituted our Raleigh representatives, one (Pseud oiiys concinna) seemed to be more herbivorous in its habits, and the other (P. scripta), more omnivorous, eating flesh as well as plants. The species are keeled when quite young, and the known young of all species with which I am acquainted are beautifulh' variegated with yellow and brown or green. Older specimens lose the keel and much of the color pattern disappears, so that many species look totally dif- ferent when young than when adult. The chicken turtle enters our list on account of its being recorded from Beaufort in Barbour and Stegneger's Cheek List, Of the habits of the animal in nature I know nothing but it differs in some respects from all our other turtles. The neck is very long, awkwardly long in fact, the shell is high and narrow, but rounded above, not keeled and the color pattern is a large meshed net work of narrow yellow lines on a brown ground. On dissecting out a specimen another marked dif- ference appears, the free portion of the ribs (between the vertebrae and the costal plates) is long, slender and rounded instead of being short, broad and flat as in all our other turtles. The diamond-back terrapin, the terrapin of the restaurants, is a salt marsh species, found only along the coast and may be recognized by the keeled shells and by the concentric lines on each plate from 66 Journal of the Mitchell Societv [September which it gets its name. While the article of diet known as terrapin should come from this species, yet as a matter of fact the sliders are also to a large extent shipped to market, though, so far I know, not from this State. One more group of turtles may be alluded to, namely, the soft- shells, which occur in the Mississippi Valley and the Southeastern States, but have not as yet been recorded from North Carolina. They have flat, orbicular bodies, a long neck, and a long pig- shaped snout, and though the edges of the lips are fleshy, yet within are sharp-cutting edges which can inflict a painful wound. The species grow to a larger size than any of our inland turtles except the snap- per, and are wholly carnivorous in diet. Little has been said about the recorded distribution of our species and actually but little is known. Raleigh, as usual, furnishes the best re-.'ords, with 7 species, Beau- fort comes next with 4 marine and 7 inland forms, while no other locality (except Lake Ellis with 6 and Greensboro and Chapel Hill with 4 each) gives us records of more than one or two species. Yet we may reasonably infer that excepting the mountain terrapin, which is confined to the mountains, and the diamond-back, which is a salt-marsh species of the coast, our prevailing forms must range from the edge of the mountains to the coast, though some of the sliders probably are only found in the eastern half of the State and the status of a few is quite problematical. A key to practically all eastern turtles follows, bj' eastern, I mean forms that are found east of the Mississippi, excluding the strictly Mississippi Valley species. The key will probably enable a tolerably intelligent person to identify most of the forms included with rea- sonable accuracy. Species already recorded from North Carolina are preceded by a serial number, the rest are in italics and unnumbered, and the name is followedby the name of State nearest to North Carolina \u which the species has been taken. Key to the Turtles of the Eastern United States 1. Limbs long, flat and paddle like : front limbs with not more than two claws each. IMarine turtles. See 2. 1. Limbs not paddle like, front limbs with three or more claws on each. Land and Freshwater Turtles. See 6. 1920] Tt/rtles of North Carolina 67 2. Shell without horny plates, covered with a black leathery skin, and with seven longitudinal ridges down back. (1) Leatherback Sea Turtle (Dermochelys coriacea) . 2. Shell with horny plates without longitudinal ridges. See ^. 3. Carapace mottled with yellow, and covered with loosely over- lapping plates. Hawksbill Sea Turtle (Eretmochelys imhricata). Tropical and subtropical seas. 3. Carapace with smooth, not overlapping, plates. See 4. 4. Claws on front limbs one each, carapace mottled with yellow. (2) Green Sea Turtle {CheJoma mydas). 4. Claws on front limbs two each, carapace without yellow mot- tling. See 5. 5. Plates on under side of bridge three. (3) Loggerhead Sea Turtle (Cfl.- etta caretta). 5. Plates on under side of bridge four. (4) Bastard Turtle {Ca- retta hempi) . 6. Shell covered with horny plates. See 7. 6. Shell covered with a leathery skin, form flattened and orbicular. Soft-shelled Turtles (Family Trionychidae). See 37. 7. Plastron narrow, cross-shaped, the plates of its central portion nine. Snapping Turtles (Family Chelydridae). See 8. 7. Plastron not narrow and cross shaped, its plates more than nine. See 9. 8. Under surface of tail with small scales : carapace with three strong keels at all ages. Alligator Snapper {Macrohelys temminckii), Georgia. 8. Under surface of tail with rather large plates, carapace with- out strong keels in adult. (5) Snapping Turtle (Chelydra serpen- tina). 9. Plastron with ten or eleven plates : front and hind portions of plastron hinged on fixed central portion and capable of partially closing the shell. Mud Turtles (Family Kinosternidae). See 10. 9. Plastron with twelve plates : plastron not as in the mud turtles. (Family Testudinidae). See 15. 10. Plastron comparatively small, hind portion capable of little movement, pectoral plate trapezoidal. Musk Turtles. See 11. 68 Journal of the Mitchell Society [Scpteiiiher 10. Plastron comparatively large, both hind and front parts moveable, pectoral plate subtriangnlar. Mud Turtles proper. See 12, 11. Head without yt^llow stripes: shell strongly keeled at all ages. Keeled Musk Turtle {Kinosiemon carinatuiii), Georgia. 11. Head with yellow stripes, at least when young, shell not keeled in adult. (6) Musk Turtle {Kinosternon odoratnm). 12. Carapace with three longitudinal yellow stripes : head with yellow stripes. Baur's Mud Turtle {Kinosternon Ixiuri), Florida. 12, Carapace without stripes. See 13. 13. Head with yellow stripes. Louisiana ]\Iud Turtle (Kinoster- non suhruhriun hippocrepis), Georgia. 13, Neither carapace nor head with stripes. See 14, 14, Plastron rather small, bridge very narrow, nasal shield deeply notched behind, Florida Mud Turtle (Kinosternon steinclachneri), Florida, 14. Plastron and bridge of normal size, nasal shield not notched behind. (7) Common Mud Turtle (Kinosternon snhrubruni [pensil- vanieton] ). 15. Plastron in two pieces, both movable on a transverse hinge, and joined to the carapace by a cartilaginous suture. See 16. 15. Plastron in one solid piece, joined to the carapace by a bony bridge. See 19. 16, Hind feet fully webbed ; shell rather long and narrow, cara- pace with small yellow dots. Blanding's Turtle (Eniys hlandingi), Ohio. 16. Shell short and high, hind feet little or not at all webbed. Terrestrial species. Box Turtles. See 17. 17. Quadratojugal arch present. Shell usually with narrow ra- diating lines on each plate. Hind feet somewhat webbed. Gulf Box (Terrapene major), Georgia. 17. Quadratojugal arch absent. Carapace with large yellow spots, or broad radiating stripes, or unmarked. See 18. 18. Claws on hind feet three each. Three-Toed Box Turtle (Terrapene Carolina triumjuis) , Georgia. 18. Claws on hind feet four each. (8) Common Box Turtle (Ter- rapene Carolina). 1920] Turtles of North Carolina 69 19. Limbs thick and club-shaped, hind limbs the smallest. Shell with concentric striae on the plates, but not keeled. Terrestrial and burrowing in habits. Gopher Turtle {Gopherus pohjphemus) , South Carolina. 19. Limbs not club-shaped, hind limbs usually the largest. See 20. 20. Masticating surface of jaws narrow. See 21. 20. Masticating surface of jaws broad. See 23. 21. Shell with concentric striae on the plates, giving each plate a lumpy appearance. Shell keeled. Terrestrial. Wood Terrapin (Clemmys insculptus), New Jersey. 21. Shell smooth without striae or keel. Shell four inches or less. See 22. 22. Head and carapace with small round yellow spots. (9) Spotted Terrapin {Clemmys guttatus). 22. Carapace and head without round yellow spots, a yellow patch on each side of neck. (10) Mountain Terrapin {Clemmys nuchaUs), Muhlenberg's Terrapin {Clemmys muhlenheyg), N. J. 23. Masticating surface of jaws with longitudinal ridge down middle. See 24. 23. Masticating surface of jaws without longitudinal ridge ; shell keeled. See 34. 24. Head and neck when extended about two-thirds length of shell, shell high and narrow, with a reticulated pattern of narrow yoUow lines in large mesh. (11) Chicken Turtle {Deirochelys .eticu- laria) . H 24. Head and neck not more than half length of shell. See 25. 25. Size comparatively small, usually not more than five inches in length of shell, shell smooth, no variegated markings on large plates of carapace. Shell with red markings around the edge. See 26. 25. Size comparatively large, adults from five inches to a foot or more in length of shell. Large plates of carapace usually with variegated markings. Plates of shell usually with longitudinal wrinkles. See 27. 26. Costal plates in line with the vertebrals so that the plates are in straight rows across the shell. (12) Painted Turtle {Chrysemys picta). 70 Journal op the Mitchell Society [September 26. Costal plates altering with vertebrals. Western Painted Turtle (Chrysemys cinerea), New York. 27. Edg-e of one or both jaws serrated. See 28. 27. Both jaws with smooth edges. Plastron with more or less black. See 32. 28. Both jaws serrated, with a notch at the symphisis of upper jaw and a strong tooth or cusp on each side of it. See 29. 28. Lower jaw only serrated, no notch or tooth at tip of up]i(n- jaw. Plastron wholly yellow. See 30. 29. Carapace red and black, plastron red. (13) Redbellied Ter- rapin (Pseudemys rubriventris). 29. Carapace as above, plastron yellow and brown. Alabama Terrapin {Pseudemys alahamensis) , Alabama. 30. Carapace smooth, head very small. Hieroglyphic Terrapin {Pseudemys hieroglyphica), Tennessee. 30. Carapace with wrinkles on the costal plates. See 31. 31. Shell comparatively short and high, markings on costal plates mainly transverse. (14) Florida Terrapin {Pseudemys floridunus). 31. Shell comparatively long and flat, markings on costal plates confused or reticulated. (15) River Terrapin {Pseudemys conciiiiKi). 31. Shell with an evident keel at all ages. An upright yellow bar behind eye. Black markings of plastron consisting of a roundish black spot on each of the two front plates (sometimes on all or nearly of the plates). (16) Yellow-bellied Terrajun {Pseudemy.'< scripfa). 32. Shell usually not keeled except in the very 3'oung. Black markings of plastron usually more extensive and elongate. See 33. 33. An oval red spot behind eye, and conspicuous yellow lines on head, neck and limbs. Red-Necked Terrapin {Pseudemijs elegans), Tennessee. 33. No red spot behind eye, markings on head neck and limbs obscure or lacking. (17) Troost's Terrapin {Pseudemys troosti). 34. Shell with concentric striae on the plates. Salt marsh species. See 35. 35. Keel of each vertebral plate knobbed at tip. Southern Dia- mond-Back Terrapin {Malaclemmys pileata),and subspecies, Florida. 1920] Turtles of North Carolina 71 35. Keels of the vertebrals not knobbed. (18) Diamond-Back Terrapin {Malaclemmiis cenfrata) and subspecies. 36. Keel of shell even, not tuberculate. A triangular yellow spot behind each eye. Map Terrapin {Graptem.ijs geographicus), Virginia. 36. Keels of vertebrals rising into knobs or tubercles on each plate, an L-shaped yellow spot behind eye. Lesueur's Terrapin {Graptemys pseudo-geographicus), Virginia. 37. Shell with tubercles in front in adult. See 38, 37. Shell without tubercles in front in adult. Brown Soft- Shelled Turtle {Amy da mutica), Ohio. 38. Pale lines on top of head united just in front of eyes. Southern Soft-Shelled Turtle (Amyda ferox), South Carolina. 38. Pale lines on top of head united near tip of snout. Spiny Soft-Shelled Turtle (Amyda spinifera), Ohio. Ealeigh, N. C. A LITTLE-KNOWN VETCH DISEASE. By Frederick A. Wolf. Plates 2-6 Introduction In the spring of 1918, a diseased condition of vetcli was noted to be quite abundantly present upon the several species growing- in the vicinity of West Raleigh, N. C, and in the following season, it was so destructive to hairy vetch, Vicia villosa, that the plants were practi- cally all killed before they had reached the flowering stage. Since hairy vetch is the species most widely grown within the State as a winter cover crop and as a feed crop to be utilized either for grazing or for hay, this disease is to be regarded as of considerable economic im- portance. All parts of the plant above ground were affected in a manner quite characteristically different from any of the several dis- eases which had previously' come under the writer's observation. It soon became apparent, from microscopic examination, however, that the disease was identical with one which had first been collected in the summer of 1907 on the horticultural grounds of Cornell Universit}-, Ithaca, N. Y. Since two concise mycological notes^ containing brief descriptions of the appearance of the disease and of the structure of the casual organism, comprise the only publications dealing with this malady, investigations were forthwith begun. It is the present purpose, therefore, to report upon these studies, which have been conducted during the past three seasons, as a contribution to our knowledge of the distribution, symptomatology and dissemination of this disease and of the life history and structure of the pathogen. Distribution It has thus far not been possible to secure any considerable body of data on the distribution of the disease either within the State or within other States where species of vetch are cultivated. It has been collected in North Carolina, however, within the counties of Forsythe, Rowan, Montgomery, Granville, Wayne, and Wake and has been observed^ by Mr. Roland McKee, Bureau of Plant Industry, Office of 1 Atkinson, G. F., and Egerton, O. W. Protocoronospora, a new genus of fungi. Jour. Mycol. 13; p. 185-186, 1907. Preliminary note on a new disease of the cultivated vetch. Sci. N. S. 26; No. 664, p. 385-386, 1907. 2 From a letter to the writer, dated May 23, 1919. [ 72 ] 1920] A LiTTiiE Known Vetch Disease 73 Forage Crop Investigations, Washington, D. C, to occur in South Carolina, Georgia, Alabama, Mississippi, Louisiana and Tennessee. Even though the disease was first collected in New York as long ago as 1907, plant pathologists generally are not familiar with it and speci- mens have, for this reason, not found their way into the several large herbaria. Since the disease has not received a common name, and has the appearance of an anthracnose, it is, in this account, designated as false anthracnose. Appearance of the Disease False anthracnose can first be noticed during November and De- cember when the plants are still small. A brownish discoloration which completely girdles the stems of the seedlings is at this time manifest. This discoloration begins near the surface of the soil and extends upward. The main stem becomes dwarfed in consequence and is soon surpassed in size bj' other shoots which develop below the lesions. In other cases, the main stem is so severely involved that it dies or the entire plant may succumb. The disease may be observed at any time during winter but makes little progress until spring. It then spreads rapidly upward upon the stem, producing characteristic, short, dark-brown to blackish streaks, Fig. 25, which may remain isolated or become so abundant as to quite uniformly discolor all of the invaded portions. Young stem lesions are at first grayish in color and their change through light brown to dark brown or black is due to the pigmentation of the mycelium within the cortical cells. Young stems are killed early in the season whereas older woody ones may live to maturity. The leaves, including stipules, petioles and leaflets, are successively^ involved, beginning with the lowermost. The lesions, except upon the leaflets, are entirely similar in outline to those upon the stems and pass progressively through the same changes in color. Those upon the leaflets may remain minute and circular with a tendency toward being most numerous along the principal veins or may appear as elongated, dark streaks. Affected leaflets are pale green in color, especially when several hundred spots develop upon a single leaflet, and become markedh^ chlorotic before the lesions attain their mature depth of color. Fig. 24. They eventually become dry and fall off. The mature spots on the legumes or pods are so strikingly dis- tinctive that there is no difficultv in distinguishing false anthracnose 74 Journal of the Mitchell Society [Septemher of vetch from any other of the diseases of this plant. Young lesions are at first manifest as irregular purplish diseolorations. The middle line of these discolored areas becomes whitish following the rupture of the epidermis by the acervulus or fruit-body of the fungus, Fig. 27. The mass of spores which comes out may give to the center of the spot a pale pink or salmon color. With age, the whitish portions of the lesions become black and the purplish halo disappears as the pods become dry. Mature lesions appear as black, elliptical or elon- gated oblique spots. Fig. 28, their direction being no doubt due to the oblique fibrous structure of the pod. Etiology False anthracnose is caused by an organism, Protocoronospora nigricans, which was described, in 1907, l\y Atkinson and Edgerton as the type of a new genus. Since, during the writer's studies, this fungus was found to possess certain characters, to be described later in this report, which are common to the true anthracnoses, compari- son was made with the several species of Gloeosporium occurring on vetch. Specimens of the two American species, Gloeosporium Davisii E. et E. and G. Everhartii Sacc. et Syd., which occur on the legumes and on the leaves respectively of Vicia autericana were loaned through the courtesy of Dr. J. J. Davis, Madison, Wisconsin, by whom they were first collected. The latter species was first described as G. ameri- canut)! E. et E^., a combination which had been earlier employed for a fungus occurring on Aranja olhens (described from Argentina l)y Spegazzini in Fungi Arg. Pug. II,, p. 36). Even tliough these two species differ in size of conidia, they will probably be found to be iden- tical when submitted to cultural and inoculation tests. Certainly they are distinct from the organism under consideration. A form which occurs on stems of Vicia cracca in France and was described^ as G. viciae Fautrey et Roum. is also very different and beyond doubt is identical with Myxosporium viciae Fautrey. There is furthermore no chance of confusing Protocoronospora nigricans with G. tricolor Lind which produces a "frog-eye" leafspot disease of Vicia cracca in Denmark.^ sProc. Acad. Nat. Sci. Phila., 1893, p. 1C7. * Fungi exsiccati precipue Oallici Centiirie LV. Revue MvcoIogi,''-, -f ' ,' '."4 PLATE 5 PLATE 6 % \ Pj^ '-^, -^^~^] A Little Known Vetch Disease 85 PLATE ;-J Figs. 13, 18, 19, and 20, are drawn to tlie same scale; the magnification of Fios 14-17, inclusive, is alike. " Fig. 13. Acervulus in cross section of Protocoronospora on vetch stem The stroma extends 3 to 4 host cell layers in depth. Fig. 14. Multinucleate mycelium taken from the margin of an acervulus Fig. 15. Variation in size and shape of conidia and in the number of nuclei liG. 16. Multinucleate cells from beneath the stroma. Fig. 17. Multinucleate conidiophores and cells of the stroma. Fig. 18. Germination of conidium on upper leaf surface of hairy vetch. The formation of the appresorium is followed by infection within 36 to 48 hours Fia 19. Infection through the epidermis on the lower surface of the leaf Fig. 20. Penetration by conidia lodged on the upper leaf surface. Fig. 21. A surface view of an acervulus six days after inoculation. PLATE 4 Fig. 22. Colonies of Protocoronospora nigricans, one week old, on vetch de- coction agar. Fig. 23. Two week's old cultures on the same medium. PLATE 5 Fig. 24. Lesions on leaves of hairy vetch. Fig. 25. Stones with elongated, dark brown to black lesions. PLATE 6 Fig. 26. Pods showing the oblique oblong lesions typical N)f false anthracnose ±IG. 27. Young lesions with whitish centers on young pods. The pod at the extreme left of the series had purplish discolored areas but fruit bodies of the causal organism have not yet been formed. Fig. 28. The dark oblique areas are lesions on mature pods. NOTES ON THE MOSQUITO FAUNA OF NORTH CAROLINA By Franklin Sherman For many j'ears the Division of Entomology, State Department of Agricultnre at Raleijih, has been accumulating records of the dilTer- ent species of mosquitoes known in the State, the localities M'here found, the months when present, etc. Recently this subject has been assumed as one of our regular projects of work. The data included in this paper were not gathered by the author alone, — Mr. R. W. Leiby, of our Division, gave a paper on mosquito control before this body a year ago, and is actively contributing to our records, — so also is Mr. C. S. Brimley. Mr. G. M. Bentley, formerly with the Division, con- tributed a number of records. Dr. Harvey P. Barrett, of Charlotte, has furnished a large number of records based chiefly on rearings from the larvae, and further work with him is conteziiplated for this 3'ear. Mr. Max Kisluik of the U. S. Bureau of Entomology, stationed at Wilmington, has furnished records from that locality. Many of our determinations have been made by authorities at Washington, notably Dr. H. G. Dyar and the late Messrs. Coquillet and Knab. The interest in mosquito control was accentuated in the State dur- ing the recent war by the work done under the Public Health Service, notably" around the camps at Charlotte and Raleigh and shipyards at Wilmington. Since hostilities ceased a number of other comniunities in the State are undertaking control work in co-operation with the Public Health Service. The importance of mosquitoes as pests of man need be only briefly mentioned : — it has been abundantly proven that malaria and yellow fever are transmitted by them. There are large areas, even in this State, where land values and crop production are lower than should be on account of malaria. We have had yellow fever cases in past years, — the particular species of mosquito which transmits yellow fever is a fully-established member of our fauna. The irritation, vexation and unrest caused by our many species which merely bite, are known to all. The main outstanding features of mosquito biology may be sketched as follows : The adult female mosquitoes lay their eggs or or near water. The larvae, called "wrigglers", Avhich hatch from these eggs live in the water, coming to the surface for air. As they are frail 1 86 J 1920] Notes on the Mosquito Fauna of North Carolina 87 little creatures quiet waters not violently agitated by storms and rapid currents, are most favorable to them. This often means stagnant water, but not necessarily so. Completing its larval life within a week or longer, it changes to a pupa, which stage lasts for a day or longer, when it emerges as an adult, winged mosquito. The length of life of the adult is indefinite, — some live over winter, some species have been kept alive in summer for two months or more. Adult mos- quitoes usually fly for distances of less than a mile, — but some species are more migratory, and with favorable light winds may travel much longer distances. The chief features of mosquito control can be briefly outlined as follows: (1) Drainage of stagnant or standing water when practi- cable; (2) straightening and clearing of drains to secure prompt disposal of the flow; (3) oiling of such waters as may still serve as breeding places; (4) stocking with small insect-eating fishes of such waters as cannot be guarded by other means; (5) screening of houses; (6) use of smudges, lotions, perfumes, etc. Accepting one mile as the general limit of flight, the Public Health Service extends the drainage work for one mile beyond the limits of the camp, yard, town or other particular area to be guarded. Most rules have exceptions,^ — and although mosquitoes adhere quite closely to the general principles just laid down, yet there are certain species which are exceptional in certain particulars and unless we know something about these exceptions, and how to allow for them, — we are liable to unpleasant and disappointing surprises, — and the public, often inclined to snap judgment, may criticise and even abandon control work which is really well done, because of the inter- vention of exceptional circumstances. Thus the control work in vicin- ity of Wilmington might be ever so well done, — it might almost, it might entirely eliminate malaria, — yet a favoring breeze might bring into that city countless thousands of mosqutoes of the species Aedes sollicitans which breed in the salt marshes of the coast ten to twenty miles away, and which is known to migrate for long distances. Such an invasion, temporary though it may be, might arouse much criti- cism. A house may be "screened," yet small species of mosquitoes may easily crawl through the meshes of an ordinary fly-screen. A pool may be oiled and yet the mosquito Mansonia perturbans may breed from it, because the larva of this species does not come to the surface for air but lives in the saturated mud about the roots of aquatic plants. 88 Journal of the Mitchell Society [September There are many variations in exact habits, — certain species are especially prone to enter houses for human victims, others seldom or never do this, — the larvae of certain species predominate in rain-bar- rels or cisterns, while others are seldom found there, — certain species are active chiefly after sundown, others are equally or more active during the day, — certain species are very averse to fl.ying in a breeze, others take advantage of it to cover long distances. The importance of ascertaining which, if any, of the disease-bearing mosquitoes occur in any locality, is self-evident. This cannot be done by disease-records, for we have no yellow-fever records at present, but we do have the yellow-fever mosquito — so far as we know, it would onl^y require the in-coming of a sufferer from this disease, at the opportune season, to start an epidemic. Hence, it requires the study of the mosquitoes themselves, the study of the mosquito-breeding waters, and the record- ing of all possible data on each separate species before we can claim to have adequate scientific data bearing upon the mosquito problem as a whole. And this phase of the subject, being the strictly entomolo- gical part of it, is the one which claims our chief attention in this The entire list of species for the State, so far as ascertained, in- cludes 32 species, while it is probable that from 10 to 15 more yet await discovery. It so happens that we have no positive record of any adult mos- quito being taken in February, but we have records for every other month of the year. The localities whose mosquito fauna is best known are : Charlotte, with a list of 23 species ; Wilmington, with 15 species ; Raleigh, 13 species; Blowing Rock, 5; Henderson County, 5; Havelock (Craven County), 5. Twenty-three other localities have from 1 to 4 species on record. Let us now adopt the convenient division of the State into three main regions : eastern, central and western. 1. Eastern. This we will consider to include all from the coast to Raleigh and Southern Pines but not including either of those two localities. Twenty-one distinct species of mosquitoes have been taken in this region, — of these, five species have not been taken in either of the other regions, so far as our present records indicate, they are exclusively eastern, — nine of the species have been taken in both the eastern and central regions but not in western, — while the remaining seven species have been taken in all three regions. 1920] Notes on the Mosquito Fauna of North Carolina 89 2. Central. We will consider this region to include Raleigh and Southern Pines and westward to the foot of the Blue Ridge, including Tryon. This reckoning places Raleigh and Charlotte (comparatively well-worked localities) in this area, and gives it a predominance, for the present, in the number of species on record. Twenty-seven species of mosquitos have been taken in this Central region, — eight of which have not yet been taken in the other areas, — nine (as before men- tioned) have been taken in central and eastern regions but not in the west, — three have been taken in both central and western areas but not in the east,- — -the remaining seven have been taken in all three regions. 3. Western. We will consider this region to include the strictly mountain area of the Blue Ridge and west of it. Ten species -of mosquitoes have been taken in this region, none of which are confined to it, — three of them having been taken in the western and central areas only, — the other seven being ones which have been taken in all three regions. It is probable that further studies will show some of the species which are now known only in our central area to occur in the eastern area also. Dr. Barrett has taken one or more southerly species at Charlotte, which is further north than they were before known to occur, and such species are very likely to occur in our eastern region whose general fauna appears to be more southerlj^ than at Charlotte. Indeed, the general showing would no doubt be considerably altered in its details, if our knowledge of our mosquito fauna, and its distri- bution, were as complete as we hope eventually to make it. Already enough is known to indicate that in number of species the central section of the State will compare with the eastern, what- ever disparity there may be in numbers of individuals, — even if all of the species now known in the central region are eventually found in the east, and if no more were found in the central region, its present list of twenty-seven species is sutScient to show that it has a mosquito fauna worthy of consideration. Owing to the presence of larger un- drained areas it is undoubtedly true that the total mosquito popula- tion is the greatest in the east, and for the opposite reason, least in the mountains. As yet the mosquito fauna of the mountains has been least explored. A complete list from that region would probably show a surprising variety, but the areas for breeding are more restricted. 90 Journal of tiii: Mitchell Society [Septeinhcr Adult mosquitoes have been found in our State virtually throujjh- out the year. The number of species which have been taken in each of the several months is as follows: January 2; February none, it so happens ; March 3 ; April 5 ; May 13 ; June 14 ; Juh' 13 ; August 21 ; September 9 ; October 10 ; November 5 ; December 3. Of the ma- larial group two species have been taken at all seasons, these winter- ing in the adult stage, — the third species of the malarial group h?*^ been taken from March to September, inclusive. The yellow-feve. mosquito has been taken June to November, inclusive. The species which perhaps breeds more abundantly than any other in eaves-troughs, cisterns and rainbarrels and which is our most common house mos- quito, has been taken April to November, inclusive. The exceptional species whose larva lives in mud at the roots of water plants and which, therefore, would not be wholly eliminated by the usual means of control, has been taken in all three regions of the State in the months of June, July and August. With so many species of mosquitoes in ever^" section (and every other State in this part of the country has a comparable list if worked up and put on record), and with many of them presenting ex- ceptions to the usual rules of mosquito life, — the intelligent and in- formed citizen will not expect perfect, absolute, complete results from any system of control work. There will be occasions when mosquitoes become abundant, by local breeding or by invasion from outside, in the best-protected areas, — they may even develop in unsuspected places inside the house itself. It has not been our purpose to here discuss the details of control further than already mentioned, — rather it has been our purpose to give an idea of the mosquito life of the State as a whole, so far as now known. Notes on the Species Arrangement is alphabetical. Man.y of the notes are from Smith "Report of Mosquitoes of New Jersey," or Howard, Dyar and Knab "Mosquitoes of North and Central America." 1. Aedes atlanticus, Dyar and Knab. An inhabitant of swamps and woods. Not known to invade houses. Taken in east part of State, — May, June and August. 2. Aedes atropalpus, (Coq.) D. and K. A small species, rather northern. Taken in central and west parts of State, — no record as to month. J920] Notes on the Mosquito Fauna op North Carolina 91 3. Aedes timaculatus, (Coq.) D. and K. A southerly species. Life and habits not fully known. Larvae taken at Charlotte in July. •4. Aedes calopus, (Meigen) D. and K. This is the species which trans- mits yellow fever. Plies and bites in day. Invades houses. Taken in east and central parts of State, — June, July, August, September, October and November. 5. Aedes canadensis, (Theobald) D. and K. Larvae in woodland pools. Adults seldom leave woods. Of wide range, but as yet taken only in east and central parts of State, — April, May, June, July and August. 6. Aedes mitcliellae, (Dyar) D. and K. A southeastern species. Taken at Wilmington in December, 7. Aedes sollicitans, (Walker) D. and K. A coastwise species, the larvae living chiefly in salt marshes, but also in brackish or fresh water. Known to fly as much as 40 miles inland. Taken at Wilmington and Beaufort on our coast, and recorded at Charlotte where perhaps carried by train, — June and August. 8. Aedes sylvestris, (Theobald) D. and K. One of the species which fre- quents porches and sometimes enters houses. A common species of wide range. Taken in east and central parts of the State, — May, June, July and August. 9. Aedes taeniorhynchus, (Wied) Busck. A coast-wise species of rather small size which migrates, but not so far as sollicitans. Bites in daytime. Does not seem to enter houses, but has been taken on porches. Taken at Wilmington and Beaufort on our coast, — May, June and August. 10. Aedes tormentor, D. and K. A southern species taken as far north as Arkansas and recorded for Charlotte in our State, — without record as to month. 11. Aedes triseriatus, (Say) D. and K. A species whose larvae live chiefly in water caught in holes in trees, — the adult being a ready biter in the woods, but not entering houses. Taken in all three regions (east, central and west) in our State, — May, June, August, September and October. 12. Anopheles crucians, Wied. This is one of the malarial group and known to be a carrier of the "aestivo-autumnal" form of malaria, but not of other forms. It bites late in day and early morning as well as at night, and readily enters houses. Taken in east, central and west parts of our State, — March, May, June, August and September. As Avith others of this group the body is usually tilted at an angle while biting. Wings spotted. 13. Anopheles quadrimaculatus, Say. This species is believed to be the most frequent carrier of malaria. Winters as adult. Taken in east and central parts of the State, not yet in the west, — January, April, July, August, September, Octo- ber, November and December. Body tilted when biting. Wings spotted. 14. Anopheles pimctipennis, Say. Has been apparently proven to transmit malaria, but not believed to do so as freely as the preceeding. Winters as adult. In our State this seems to be the most common of the three species of the malarial group. Taken in east, central and west parts of State in every month with one exception (Feb.) Body tilted when biting. Wings spotted. 15. Coclodiazesis harheri, (Coquillet) D. and K. Breeds in water in holes in trees, and sometimes present in woods when country is so dry than few other kinds are present. A small species. Our only State record is from Tryon at foot of mountains, without mention of the month. 92 Journal of the Mitchell Society [September 16. Culcx floridanus, D. and K. A very small southern species, recorded from Charlotte for July and August. 17. Culex melanurus, Coquillett. A dark-colored species of wide range which apparently does not- bite. Our only record is from White Lake (Bladen County) in May. 18. Culex pcccator, D. and K. A rather small southern species, recorded from Arkansas, and from Charlotte in our State in August. Apparently a fre- quenter of caves and tree-holes. Not known whether it bites. 19. Culex quinquefasciatus, Say. This is probably our most abundant and universally-present house-frequenting mosquito. Larvae abundant in raiubarrels, cisterns, troughs, temporary pools, sluggish and foul water, etc. Corresponds to the common C. pipiens of the northern States. Taken in east, central and west parts of the State, — April, May, June, July, August, September, October and November. 20. Ctilex restuans, Theobald. In general character like the preceeding, but not so abundant, nor breeding in so foul water. Our records are from the central and west parts of the State, — June and October. 21. Culex salinarius, Coquillett. A species of wide range, though also occur- ring close to coast, hence the name. Enters houses. Taken in east and central parts of the State, — May, August, September^ October and November. 22. Culex territans, Walker. A rather small, dark species which perhaps does not bite persons. Our only records are for Charlotte and Blowing Rock, — August. 23. Culiseta inornatus, (Will.) Dyar. A rather large species which freely bites cattle and horses, perhaps in preference to man. Of wide range but our few records are from Wilmington and Charlotte, — INIarch. 24. Mansonia perturbans, (Walk.) Dyar. The larva lives in mud at roots of aquatic plants, not coming to surface for air. A species of wide range. Enters houses. A fierce biter. Taken in east, central and Avest parts of the State, — June, July and August. 25. Megarhinus septentrionalis, Dyar and Knab. A very large mosquito with metallic blue lustre, often found on flowers. Taken east, central and west in the State, — July, August, September and October. 2(5. Ortlwpodomyia signifier, Coquillet. A wide-spread species not positively known to bite. Our only records are from Raleigh and Charlotte, — October. 27. Psorophora ciliata, (Fab.) Rob. — Des. A large species with erect scales on the legs giving fringed appearance. Ready biter and goes indoors, but not usually abundant in houses. Taken in eastern and central parts of State, — May, June, August, October. 28. PsoropJiora columhae, Dyar and Knab. A day as well as evening biter. Seldom indoors. East and central parts of State, — May, July, August. 29. PsoropJiora discolor, Coquillett. Our only record is from Charlotte, — July and August. 30. Psorophora houmrdi, Coquillet. A large species, of which our only record is Charlotte, — without indication of month. 1920] Notes on the Mosquito Fauna of North Carolina 93 31. PsoropJwra sayi, Dyar and Kiiab. A species of wide range, a severe day biter, but apparently not usual in houses. Our records are from east, central and west parts of the State, — May, June, July, August and September. 32. Wyeomyia smithii, (Coq.) Felt. The larva of this species is known to live normally in the water contained in the stems of pitcher-plants. The adult is not known to bite. Our only record is from Boardman (Columbus County) — larvae in pitcher-plant in April. Raleigh, N. C. AN INTERESTING FERTILIZER PROBLEM By H. B. Arbuckle Last summer a large number of farmers in Rockingham county suf- fered almost total loss of their tobacco crop. It so happened that one of these farmers used two bags of fertilizer that he had kept over from the previous year. He observed that the rows of tobacco upon which he used this old fertilizer to the very plant in the row where he changed to the new fertilizer grew off well and produced well. All the rest of his tobacco was stunted and never showed any growth except in very rainy M-eather. This was sufficient to fix suspicion upon the new fertilizer. This led to my investigation. The fertilizer was marked "For Tobacco" and the tag showed a guaranteed analysis, 8-2-2. On analysis the fertilizer checked up very well as 8-2-2. The nitrogen was a little low as determined by Kjeldahl, showing approximately 1.5. It is inter- esting to note that when the nitrogen was determined by Dumas, it ran distinctl}' higher. The fertilizer was at once tried out on boxes of clover and rye at the rate of 1,000 lbs. per acre and compared with a fertilizer prepared in the laboratory to yield 8-2-2, the potash being supplied as potassium sulphate and the nitrogen as sodium nitrate. In these experiments the fertilizer under investigation showed up to tine advantage, showing distinct advantage over the prepared fertilizer. Having no tobacco plants at this time, the fertilizer was reported as good, but the farmers insisted that it be tried out on tobacco. After growing a lot of tobacco plants a set of boxes was prepared to test this fertilizer in varying amounts and other fertilizers prepared with potash and nitrogen from different sources. Having discovered that the fertilizer under test contained over l/{ of chlorides and knowing that chlorides were not good for tobacco, the chlorine was removed from the fertilizer. It was found that the tobacco plants in the boxes in which 600 lbs. was used in the row or 1,000 lbs. mixed with the soil were nearly all killed. The few plants remaining were pale and sickly and produced no growth in two months time. The plants in those boxes fertilized with 1,000 lbs. of the fertilizer with the chlorine re- moved grew nicely, comparing favorably with tlie best fertilizers pre- pared for tobacco. [ 94] 1920] An Interesting Fertilizer Problem 95 Knowing- that one per cent of chlorine could not kill tobacco, boxes were prepared in which we used as much as 200 lbs. of sodium chloride per acre. As was expected this did not injure the plants. The chlo- rides do not affect the growth, but only the burning' quality of the tobacco. We next tried the fertilizer on tomato plants and found that these were injured, but not as much as the tobacco plants. Then we investi- gated various solutions of the fertilizer. We found it was the water solution alone that injured the tobacco. A small plant in a beaker was killed in twenty-four hours by the application of a solution that repre- sented 2,000 lbs. per acre. Next we removed the organic matter by prolonged heating, taking up the ash with hydrochloric, sulphuric and nitric acids. The plants were injured not at all by the M^ater solution of these salts, but little growth was shown, because the organic matter unquestionably stimulates plant growth, as could be shown in the study of stable manures. It was noted with interest that the nitric acid solution gave after a time a most vigorous growth. This might have been expected. We then tried water solution of the fertilizer under investigation after heating for an hour at 120° for thirty min- utes. We found that this solution when applied in quantities repre- senting 1,000 lbs. per acre gave excellent results. The toxic substance or substances present seemed to be removed or changed by heat. We repeatedly demonstrated the good results with the fertilizer thus treated. We now had the explanation of the puzzling fact about the chlorine.. In removing the chlorides with silver sulphate, heat was employed to avoid the loss of the phosphates. The heat had destroyed the toxic substances in this case as in the case of the straight samples. B.y accident we discovered that the toxic substances are also re- moved by leaving the fertilizer exposed to the sunlight in a warm place, as a bottle containing the fertilizer was left for one week in the balance room where it was exposed to strong light from the south. Water solution of this exposed fertilizer had no effect whatsoever on tobacco plants. Thus it appears that there is an organic substance present in this fertilizer, which is toxic to tobacco plants and tomato plants, while it has no effect upon rye and clover. This toxic substance is made harm- less by heating or by exposure to sunlight. What the substance is still remains a puzzle. Thinking it might be a nitrogen compound, prob- 96 Journal of the Mitchell Society \Scpteni'ber a])ly an amido eompouiid derived from decomposition of tankage or some form of animal nitrogen, we determined the nitrgen in samples of the fertilizer after it had been rendered harmless. The percentage was higher than in the original sample. This, however, may be due fact that the water content had been changed. Unfortunately, we had not determined this in the original samples. AVe carried through a set of experiments to see how many organic substances containing nitrogen were toxic to tobacco plants. These experiments showed several substances that were quite toxic, notably the nitro phenols, pyridine and piperidiue. This was but a confirmation of experiments conducted by Cameron. Here is an in- teresting problem that deserves the attention of the fertilizer manu- facturer, especially in this day, when he is ransacking the world to find sources of potash and nitrogen. In the future will it not leave the manufacturer liable if he sells a fertilizer with a guarantee that it will grow a particular crop and it is found to injure it? In this particular case the tobacco fertilizer did enormous damage. It can be rendered harmless in a very simple way, but it is the manufacturer's job to discover this and not the farmer's. This should lead to the testing out of samples of every fertilizer sold for a par- ticular crop. Davidson, N. C. AZALEA ATLANTICA ASHE AND ITS VARIETY LUTEO- ALBA N. VAR. By W. C. CoKER Plates 1 and 7 For about eight years I have had under observation a striking spe- cies of Azalea, a typical and abundant constituent of low, damp, pine barrens of the coastal plain. My brother, James L. Coker, Jr., first called my attention to the distinction between this species and A. nudiflora, which blooms at the same time and with which it is often confused by careless observers. The species is not included in the treatment of the genus in the North American Flora by Dr. Small, but in April, 1917, Mr. W. W. Ashe published in the Bulletin of the Charleston Museum (13 : 26. 1917) a new species, Azalea ailantica, the description of which agrees well with our plants except that the color was said to be rose-purple or reddish. As our plant has essentially white flowers throughout its range it seemed improbable that they could be the same. However, on talking with Mr. Ashe he admitted that the flowers were nearly pure white when open, thus removing the principal point of difference. I have also now at hand a specimen in flower from the type locality (Georgetown, S. C.) sent me by Mr. T. G. Harbison on April 26, 1918, and find it the same as Hartsville specimens in all essentials. T now have the plant (from Hartsville) in cultivation in the Arboretum of the University of North Carolina, where it flowered this year. Azalea atlantica Ashe. The typical form of the species, as I have observed it, may be described as follows : Shoots low, slender, strict, hairy or glandular when young, smooth later, sparingly branched, about 1.5-55 cm. (6-18 in.) high, springing from underground runners and thus forming extensive colonies ; leaves up to about 4 cm. long and 1.7 cm. broad, elliptic to obovate, the base pointed at the very short petiole, the tip with a short mucro, margin not recurved or slightly so, ciliate with curved tooth-like hairs, upper surface smooth or sparingly pubescent, the lower nearly smooth or moderately pubescent, grayish-green, the midrib not ciliate (or ciliate, at least when young, in the Georgetown plants). Flowers appearing during the Avhole of April, 3-4.5 cm. long, glandular and sparingly pubescent or only glandular, not hairy, very fragrant, unfolding before the leaves or in part lagging and simultaneous ; corolla tube 2-3 cm. long, expanding 98 Journal of the Mitchell Society [September into the open throat, the acute petals with a spread of ?>-4 cm., color pure white when open except for a blush of pink or purple on outside near base of ti'.])e; the buds more pink. Calyx two-thirds to three-fourths as long as the fivary, varying (in the North Carolina plant) to nearly as long, the strap-shaped lobes blunt, unequal, and upright (recurved or revolute on drying at times), separate to near or below the middle, glandular only or both glandular and with the margin hairy; ovary about 4 mm. long and 3 mm. thick, style about 4-6 cm. long, pale pink to greenish white, hairy (not glandular) over loAver half or two- thirds, the knob-like stigma greenish brown; stamens well exserted (about 2 em.), but not nearly so much so as in A. nudiflora, Avhitish or pale green; pedi- cels about 7-13 mm. long, pink or greenish. Mature pods about 2 cm. long and 6-7 mm. thick, pointed, somewhat curved, nearly glabrous, dark. Floral glands reddish, very short-stalked, present on pedicels, calyx, ovary and on the outside of the corolla tube and along the central keels of the spreading lobes. Odor strong and very pleasant. Azalea atlantica var. luteo-alba n. var. Flowers smaller, white when open, the buds and opening flowers with a de- cided yellowish tint ; not pinkish. Otherwise as in the type. Occurring in sim- ilar habitats as the type but in separate colonies, and not intermixed. We have found it only at Hartsville, S. C. A well-marked species that is easily distino-nished from A. nudi- flora, which occurs plentifully in the same territory, though rarely intermixed. It differs in the white, very fragrant, and viscid-glandu- lar (not hairy) tlowers with longer tubes, more open throats, much larger calyx, shorter and stouter ovary, and less exserted stamens; by the dwarf size and extensive underground runners ; and by the absence of cilia on the midrib. The habitat is also not the same, A. atlantica being found in low, damp, undrained pine flats of the coastal plain, while A. nudiflora prefers the better-drained soil by ditches, branches or bluffs and extends far beyond the range of the former. Azalea viscosa, which is really nearest, is, of course easily distinguished by large size, late flowering (late May to July), and different habitat and habit. It is the only other Azalea of the region occupied by A. atlantica and A. nudiflora, with the possible exception of the next. Azalea canescens, which has the leaves whitish-pubescent below, occurs on better-drained soil, is rose-flowered, is not viscid, and has the same size and habit as A. nudiflora, which is very near. Compared with specimens of A. canescens at the New York Botanical Garden our plants were easily seen to be different. One plant from Orangeburg, S. C, in the New York Botanical Garden Herbarium, labelled A. 1920] Azalea Atlantica Ashe 99 canescens but different from the others, may be our species. Azalea glauca, which seems a small form of A. viscosa occurs from New Eng- land to Virginia and blooms from June to July, Azalea atlantica is one of the most conspicuous flowers of the damp, flat woods of the low country, often covering acres under old field or long-leaf pine, and scenting the air for a long distance with a frag- rance that is far more pleasant than the much less obvious odor of A. nudiflora. We have the plant from Georgetown, S. C, Hartsville, S. C, and Brunswick County, N. C, and have seen it in New Hanover County, N. C. It is probably distributed over most of the coastal plain of North Carolina and South Carolina. The plants from Bruns- wick County are a slightly different form from the South Carolina plants. The calyx is not hairy, the leaves are smooth on both sides, and the flowers are glandular only. In the Georgetown and Harts- ville plants the calyx lobes are a little shorter and less fused, and are quite hairy on the margin in addition to being glandular; further- more, the flowers are slightly tomentose as well as glandular. Plate I was painted by my niece, Dorothy Coker, from Hartsville plants on April 25, 1915. It is 4/7 natural size. The photograph (Plate 7) was made by me in Brunswick County, N. C, about half way between Wilmington and Southport on April 6, 1918. Chapel Hill, N. C. • A NEW SPECIES OF ACHLYA By W. C. CoKEK and J. N. Couch Achlya Orion n. sp. Hy])lial threads long, reaching a length of 1.5 ems. on honse-flies, more slender than in most Achlyas, from 10-40/x thick close to base, rarely up to 85/i, thick, often wavy; usually little branched and pointed at tips when young ; becoming considerably branched with age. Sporangia abundant, cylindrical, usually" borne singly on the tips of the main hyphae in young cultures, renewed by cymose branch- ing, often forming several clusters at regular intervals on the same hypha, irregular and wavy in old cultures, 12-37 x 36-600/x (rarely up to 900/i,). Spores 9-10/x thick, emerging as usual in Achlya, but often falling to the bottom in an open group instead of forming a sphere at the sporangium mouth. Oogonia abundant on flies, grubs and vegetable media, spread over the entire culture from bases of h3^phae to tips, giving the culture a lacy interwoven or net-work ap- pearance ; the diameter 30-60/x,, commonly 32-48|U. ; usually borne singly on long, crooked, recurved stalks which arise racemosely from main hyphae and which vary in length from 2-10 times the diameter of •the oogonia; often oogonial stalks ma.v branch bearing two oogonia and rarel.y oogonia may be borne on a stalk which arises directly from another oogonial wall ; very rarely intercalary ; oogonial wall usually without pits (except where the antheridial tubes enter) when grown on flies or grubs, but as a rule with pits when grown on boiled corn. Eggs 1-8, usually 1 or 2 in each oogonium; 25-45/i, in diameter, most 33-36/a, eccentric when ripe with one large oil drop ; usually spherical, but often elliptical from pressure. Antheridial branches almost always androgynous, usually arising from the oogon- ial stalk itself, less often from the main hyphae ; rarely diclinous ; an- theridia on about 75% of the oogonia, one or two on an oogonium, tuberous; antheridial tubes obvious penetrating the oogonia and reaching the eggs. The species seems to be quite rare, having been recognized only twice in considerably over a thousand collections, made by the senior author and his students. It was found in some water and trash collected from the west branch above the Meeting of the Waters 1930] A New Species of Achlya 101 (No. 6 of September 26, 1919), and in the same kind of material from the branch in Battle's Park behind Dr. Pratt's residence (No. 4, June 10, 1920). The description has been made from cultures de- scended from a single spore. Our plant can be distinguished (with the unaided eye) from most other Chapel Hill Achlyas by the network appearance given it by the oogonia being scattered over the entire culture from the bases of the hyphae to the tips. Achlya race))wsn approaches this network appearance more than any other species of Achlya but in the latter the oogonia are not nearly so abundant nor do they extend entirely to the tips of the hyphae. In some species, such as Adilya oblongata, the oogonia are borne in a definite zone near the substratum and from half to two-thirds of the length of the hyphae from the tips backwards are without oogonia. In the Prolifera group the oogonia are scattered more or less over the entire culture but the big hyphae and long sporangia dissipate the net work appearance. If we ignore the egg structure, the present species seems to be closest to Achlya polyandi a Hildb. The two plants resemble each other in the long, racemose oogonial branches which are recurved at the tip ; in the often branched antheridial stalks which arise chiefly from the oogonial branches ; and in the smooth oogonial walls which are normally without pits except where the antheridia touch. The two species are readily distinguished, however, by the difference in the number of eggs in the oogonia, and in the size and structure of the eggs. In Achlya polyandra the number of eggs varies from five to twenty-five, the usual number being ten to fifteen, their average diameter is 27ju, and they are said to be centric ; in A. orion the usual number of eggs is one to two, the diameter of most 33-36ju,, with an eccentric structure. In Achlya polyandra the sporangia are reported as often not abundant, and secondary ones rare ; while in our plant both primary and secondary sporangia are abundant. This species is named for the nebula in Orion, which a photograph of the magnified culture somewhat resembles. This photograph, together with draw- ings by J. N. Couch will appear in a volume by W. C. Coker on the Saprolegniaceae of the United States to be published soon. DOUBLE NUMBER VOL. XXXVI FEBRUARY, 1921 No8. 3 & 4 JOURNAL OF THE Elisha Mitchell Scientific Society CONTENTS Proceedings of the Elisha Mitchell Scientific Society, May, 1920, to December, 1920 103 James Jacob Wolfe, 1875-1920 no The Chemical Behavior of Zirconium. F. P. Venable 115 A Pure Culture Method FOR Diatoms. Bert Cunningham .. . 123 The Occurrence of Unlike Ends of the Cells of a Single Filament of Spirogyra. Bert Cunningham 127 Some Marine Molluscan Shells of Beaufort and Vicinity. Arthur P. Jacot 129 Notes on the Thelephoraceae of North Carolina. W. C. Coker 146 ISSUED QUARTERLY CHAPEL HILL, N. C, U. S. A. ENTERED AT THE POST OFFICE AS SECOND-CLASS MATTER The Elisha Mitchell Scientific Society A. H. PATTERSON, President. *^ A. W. HOBBS, Vice-President. J. M. BELL, H. R. TOTTEN, Permanent Secretary. Recording Secretary. Editors or the Journal: W. C. COKER, Chairman. J. M. BELL. COLLIER COBB. Journal op the Elisha Mitchell Scientific Society — Quarterly. Price $2.00 per year; single numbers, 50 cents. Most numbers of former volumes can be supplied. Direct all correspondence to the Permanent Secretary, at the University of North CarolLaa, Chapel Hill, N. C. In addition to original papers on scientific subjects this Journal pub- lishes the Proceedings of the Elisha Mitchell Scientific Society, and the Proceedings of the North Carolina Academy of Science, as well as abstracts of papers on scientific subjects published elsewhere by members of the Fac- ulty of the University of North Carolina. Published for the Society by the University of North Carolina JAMES JACOB WOLFE 1875 1920 JOURNAL SOTAfV ;■<.•■. A L Elisha Mitchell Scientific Society Volume XXXVI FEBRUARY Nos. 3 and 4 PROCEEDINGS OF THE ELISHA MITCHELL SCIENTIFIC SOCIETY, MAY, 1920, TO DECEMBER, 1920 241sT Meeting— May 4, 1920 W. deB. MacNider — On the Relation of the Amount of Stainable Fat in the Renal Epithelium to the Susceptibility of the Kidney to the Toxic Effect of the General Anesthetics. Frozen sections were made from fresh kidney tissue and stained for fat with Scharlach R by Herxheimer's method. Such tissue when obtained from puppies and young dogs shows fat as minute dust-Hke particles in the epithehum of the ascending Umb of Henle's loop. Kidney tissue obtained from old and very senile animals shows a marked increase in the amount of fat in the ascending limb of Henle's loop and fine dust-like particles of stainable fat in the convoluted tubule epithelium. Kidney tissue obtained from natur- ally nephropathic animals shows a large amount of stainable fat not only in the ascending limb of Henle's loop but also in the convoluted tubule epithelium. When such animals of different age periods and naturally nephropathic animals are anesthetized by ether, the relative toxicity of the anesthetic for the kidney is shown in the following manner : 1. The puppies and young dogs continue to form urine during the course of the anesthesia and remain responsive to diuretic solu- tions. 2. A certain number of the adult and senile normal animals become anuric and fail to respond to diuretic solutions. Other animals in this group remain diuretic for the earlier part of the experi- ment and later become anuric. [103] 104 Journal of the Mitchell Society [Fehruanj 3. All the naturally nephropathic animals become anuric in the early stages of the experiment and remain anuric and non-responsive to diuretic solutions throughout the experiment. A. W. HoBBS — Einstein's Special Relativity Theory. The laws of Nature must be invariantive, that is they must be so stated as not to depend upon any particular frame of reference. All attempts to discover different values for the velocity of propaga- tion of light in different directions have failed. We then assume the constancy of the velocity of hght. This leads to the conclusion that x^+y^+z-— C't^ must be changed into the same expression when we refer to another system (i. e.) x^+y^-f-z- — c-t^ = x'2-fy''' + z'2— c^t'^. The Lorentz transformation accomplishes this and is at the same time consistent with experience. It is given by x' = /3 (x - vt) where /3 = (1 - -j)~^ y'= y z' = z t' = ^(t-^') Applying these equations we find that a length X2 — xi is shortened in V" 1/ the directions of motion by the factor (1 - — ) ^2. The paralellogram law for the addition of velocities is no longer U + V u + V but 1 +UV These results would have very little interest to most of us if they did no more than add very small corrections to our already compli- cated system. The interest lies in the fact that they point to an almost organic relation between space and time, so that we must not consider space and time as being distinct concepts. 242nd Meeting— May 25, 1920 Dr. C. E. McClung, Professor of Zoology, University of Pennsyl- vania— The Material Basis of Heredity. The lecturer, covering the chromosome theory of heredity, in- troduced the principal facts, including the speaker's own well known discoveries showing a correlation between the presence in germ cells of particular chromosome masses and sex. (H. V. W.) 1921] Proceedings of Elisha Mitchell Scientific Society 105 Election of Officers: President — A. H. Patterson. Vice-President — ^A. W. Hobbs. Permanent Secretary — J. M. Bell. Recording Secretary— K. R. Totten. Editorial Committee — W. C. Coker, chairman; J. M. Bell, Collier Cobb. 243rd Meeting— October 19, 1920 H. V. Wilson — The Mode of Origin of the Nervous System in the Vertebrate Embryo. Some recent operative experiments made by Professor Hans Spemann on the salamander embryo were described. These experi- ments showed that a patch of embryonic tissue might be developed into spinal cord, brain, eye, or ordinary epidermis, according to the locality in which it is placed, and seem to constitute decisive evidence against the view that the organs of the body are represented in the egg by localized peculiar substances. Election of Members: The following members of the faculty were elected to active membership in the Society: Dr. Otto Stuhlman, Dr. E. A. Abernathy, Capt. Frederick W. Boye, Mr. H. M. Taylor, Mr. H. G. Baity, Mr. W. E. Walke, Mr. Walter B, Jones. The following advanced students and assistants were elected to associate membership: C. P. Savage, Eleanor Hoffmann, P. R. Dawson, T. P. Dawson, R. A. Lineberry, S. C. Smith, A. M. Wolfson, H. L. Cavaness, B. Naiman, R. O. Deitz, S. C. Ogburn, A. B. Owens, F. P. Brooks, J. W. Guard, C. R. Harris, N. W. Taylor, D. M. Carroll, C. B. Ridge, C. J. Bryan, D. St. P. DuBose, W. F. Foote, T. E. Hinson, E. J. Mecum, L. V. Milton, J. D. Morris, P. C. Smith, A. B. Wright, R. M. Casper, M. E. Lake. T. B. Smiley, W. H. Butt, H. S. Boyce, S. B. Lee, J. B. Miller, B. E. Lohr, Roy J. Morton, L J. Stephenson, Clayton Edwards, S. C. Alston, J. B. Noe, F. R. Bacon, J. B. Broach, S. M. Crisp, A. L. Miner, J. W. Harrell, Jr., J. L. Cobb, M. L. Jacobs, J. M. Alexander, Wm. F. Alston, P. M. Grey, A. H. Merritt, J. G. Tucker, C. D. Beers, H. S. Everett, Ernest Atkins. 244th Meeting — November 9, 1920 The Society passed the following Resolution : Whereas, the Elisha Mitchell Scientific Society was organized for the purpose of encouraging scientific investigations in North Carohna; and 106 Journal of the Mitchell Society [February Whereas, European Forestry has depended upon and reaped much benefit from the Forest Experiment Stations of the various countries; and Whereas, several such experiment stations have been estabUshed in the western part of the United States and none in the eastern states; and Whereas, we reaUze the importance of securing more accurate knowledge con- cerning methods of management for the perpetuation of the valuable forests of the Southern Appalachian region; therefore be it Resolved, that we go on record as strongly favoring the establishment of a For- est Experiment Station by the United States in the vicinity of Asheville and do hereby respectfully urge Congress to pass the bill providing for such station. C. S. Goodwin and C. R. Monroe were elected to associate member- ship in the society. J. M. Bell — Further Studies on the Nitrotoluenes. This paper was the result of a continuation of work begun at the request of the National Research Council on the freezing points and thermal properties of the nitrotoluenes. The particular nitro- toluenes investigated are those formed in largest amounts during the nitration of toluene to TNT: viz., orthonitrotoluene (ONT) ; para- nitrotoluene (MNT); 1, 2, 4-nitrotoluene (DNT); and 1, 2, 4, 6- trinitrotoluene (TNT). There are two melting points for ONT, corresponding to the two crystal forms of this compound ; the stable form (m. p.-4.5°) and the metastable form (m.p.-10.5°). The follow- ing systems were investigated: ONT-DNT and ONT-MNT-DNT (with E. B. Cordon); ONT-MNT and ONT-MNT-TNT (with F. H. Spry); ONT-TNT and ONT-DNT-TNT (with Woodford White). A formal presentation of the results is to be made in early issues of the Journal of Industrial and Engineering Chemistry. A. H. Patterson — Recent Work on Spiral Nebidae. A review of the recent work done at Mt. Wilson and elsewhere on the Nebulae, Wolf-Rayet Stars and Stars of Classes B and A; the theory of the origin of Spiral Nebulae was outlined, and lantern slides shown of various types of spiral and quiescent nebulae; the relation between velocity and temperature of the stars and nebulae was touched upon, and the significance of the Spiral Nebulae some- times occurring in pairs was pointed out. 245th Meeting — December 14, 1920 J, W. Lasley, Jr. — Some Developments in Modern Geometry. Einstein's results resolve the problem of understanding the laws of the universe into the problem of understanding geometry. It was 1921] Proceedings of Elisha Mitchell Scientific Society 107 a contribution of Klein to see in group theory a logical classification of geometry. Classified from the viewpoint of groups of transform- ations, geometry falls into projective geometry, metric geometry, etc. Some investigations require a knowledge of a geometric figure only in a limited region; others require a knowledge of the figure as a whole. We are thus led to a sub-classification: differential and in- tegral geometry. Four kinds of geometry thus arise: the projective differential geometry of Halphen, Wilczynski and Green, the pro- jective integral (known as projective) geometry of Desargues, the metric differential (known as differential) geometry of Gauss, and the metric integral (known as geometry) geometry of Euclid. The developments in geometry to which this paper calls attention are those in the field of projective differential geometry, C. S. Mangum — A Review of the Public Health Work in North Carol- ina. Progress in health work is indicated by a reduction in death rates. For the whole United States the death rate is 12.9 per thousand of population. In North Carolina it is 12.4. This is lower than the known death rate in any other of the old states from Maine to Texas. This record is all the more creditable when one considers the fact that North Carolina's birth rate is the highest of all the states in the Union, and is steadily increasing. The State Board of Health, in conjunction with allied associations, has for years conducted a well organized and energetic campaign which has shown most encouraging results in a number of fields. In 1914 there were 8,390 cases of typhoid fever and 839 deaths. In the last twelve months there have been 2,750 cases with 275 deaths. A reduction of two-thirds. Within the same period the death rate from diphtheria has been cut in half. In 1914: deaths 525. In 1920: deaths 242. The deaths from tuberculosis have decreased from 3,710 in 1914, to 3,005 in 1920. A gain of 705. The work of the Board may be classified under three heads: (1) Educational. Through the wide distribution of the ''Bulle- tin" and thousands of special pamphlets, public lectures and pubhcity campaigns; using the County as a unit. (2) Prophylactic. Supervision of the care of expectant mothers and of infants; Intensive campaigns against preventable diseases, distribution free or at a nominal cost of vaccines and antitoxins, 108 Journal of the Mitchell Society [February supervision of public water supply, sewage and sanitation, and the making of water analyses and many other laboratory tests. (3) Directly Remedial. Free clinics for the treatment of venereal diseases; Medical inspection of the public school children followed by free dental clinics and the removal of diseased tonsils and adenoids. The Public Health Work is under the direction of a general staff, the State Laboratory of Hygiene and eight special bureaus. 1. Laboratory of Hygiene: Supplies Vaccines, Antitoxins and Pasteur treatments; makes water analyses and Wasserman and other tests. 2. Bureau of Vital Statistics: Collects information which insures the efficient direction of the work. 3. Bureau of Tuberculosis: The State Sanatorium treats an average of 135 cases each year, examines and advises over 1000 others, and conducts intensive County Campaigns. 4. Bureau of Medical Inspection of Schools: In the past two years 150,000 public school children have been examined; 25,587 have been given free dental treatment and 2500 have had diseased tonsils or adenoids removed. 5. Bureau of County Health Work; Forty counties have full time health officers and 22 have full time public health nurses. Within the past two years 40,000 insani- tary privies have been eliminated, principally in rural communities and in small towns. 6. Bureau of Engineering and Inspection : For supervision of public water supply and sewage disposal. 7. Bureau of Venereal Diseases: Sixty thousand persons have received treatment in the last 2 years at the free clinics. Educational campaigns are being conducted in the comities by: (1) A physician who goes into the coimty to arrange dates and arouse interest. He is followed by: (2) The "educational truck" carrying a physician to lecture to the men, a woman to lecture to the women, a moving picture machine and a negro physician to lecture to the negroes. 8. Bureau of Epidemiology: Conducts the fight against infectious diseases. In the last 2 years 165,000 people have been given the free protective treatment against typhoid fever. J921] Proceedings of Elisha Mitchell Scientific Society 109 9, Bureau of Public Health Nursing and Infant Hygiene: In 2 years has given aid and instruction to 11,000 expectant or new mothers, who needed intelligent care for themselves and their babies, that they were unable to secure. The economic value of this work is tremendous when computed in terms of the economic value of a human life, which is about $3500.00, but the intangible values based upon better health, greater efficiency and longer life are beyond computation. JAMES JACOB WOLFE 1875-1920 Plate 8 The North Carolina Academy of Science has lost in Dr. Wolfe one of its most active, influential and useful members, and desires to put on record a sincere and affectionate appraisal of his character, his personality, his work and his service to the Academy, to Trinity College and to the State. He was born on September 14, 1875, at Sandy Run, Calhoun County, South Carolina, the son of John Archie Wolfe and Frederica A. (Geiger) Wolfe, was educated at Wofford College, and pursued graduate training at University of Chicago, and at Harvard, receiving the degree of Doctor of Philosophy from the latter University in 1904. He was at once elected Professor of Biology in Trinity College, and filled this position with marked ability and distinction as teacher, investigator and administrator until his death, after only a short illness, on the morning of the College Commencement Day, June 9, 1920. On June 28, 1904, he was married to Cornelia Wilhelmina Lehr- mann, of Montclair, N. J., who survives him. There are no children. Dr. E. W. Gudger, for many years head of the Biological Depart- ment at the State College for Women, and now of the American Museum of Natural History, New York, writes as follows: "I knew Professor Wolfe for some twelve years, and for ten years of that time intimately. He was an unusual man in every way. Some years after we became friends, he came down to the U. S. Fisheries laboratory at Beaufort to take up the study of certain marine algae, and it was my good fortune to introduce him to the life of a marine biological laboratory. From that time on our friend- ship grew and our intimacy was terminated only by his all too early death. "In his scientific work, Professor Wolfe was careful, painstaking, and thorough, testing every observation and phenomenon to the far- thest limit before committing his observations and conclusions to writing. In his work on the alternation of generations in one of the marine algae, his observations and results were at variance with those of previous workers. Here, instead of rushing into print with something startling, he patiently reviewed his work year after year until he was absolutely sure of his results. At the time of his death Professor Wolfe was engaged, with the assistance of Mr. Bert Cun- [1101 1921] James Jacob Wolfe 111 ningham, in an extensive and far-reaching investigation for the U. S. Bureau of Fisheries on our marine diatoms, and had he been spared to finish this it would have been the. authoritative monograph on these plants in our waters. "As a teacher, Professor Wolfe was one of the most successful instructors in his subject in North Carolina. Under him the depart- ment of Biology in Trinity College grew steadily in numbers of stu- dents and in influence, and at the time of his death he had plans on foot for a very great enlargement and development of his depart- ment. "In the North Carohna Academy of Science, Professor Wolfe was one of the most influential and valuable members. Never ab- sent from a meeting, he could always be counted on for any needed work. During my eleven years' incumbency as Secretary I called on him scores of times for advice and help, and it was always his pleasure, and, as he put it, his 'privilege,' to serve the Academy. This ready devotion of his was appreciated by all the members, and was signalized in 1914 by his unanimous election to the office of President. "Professor Wolfe's life was as square and straightforward and honest as was his scientific work. I who knew him intimately knew him always four-square to the world. Generous and whole-souled himself, he always looked for these qualities in others. He was one of the most delightful hosts I have ever known, and no one ever visited him and Mrs. Wolfe in their delightful home at Trinity Col- lege without bringing away recollections of the very finest hospitality. He was a man of the most genial and lovable personality. "Of what Professor Wolfe's death has meant to me personally it is hard for me to speak. For more than ten years I have had in him an intimate friend on whom I could rely to the limit, and his going has made the world much poorer for me." This impression of fine-souled solidity of character was shared by all who knew him. A co-worker with Dr. Wolfe along certain lines, who saw him often and was able to judge him fairly, is Dr. W. C. Coker, head of the Department of Botany in the University of North Carohna, who bears this testimony: "I have been asked to give my impression of Dr. Wolfe as a man, as an investigator and as a member of the North Carolina Academy of Science. "It is significant that as I recall him as a man and as a friend my thoughts have no element of uncertainty or complexity, but rest quietly as though carried on a tranquil stream. Wolfe was a simple man, as all good men are, or rather one might say the impression was that of simplicity, and always the same. It could not be other- wise with one who so fully combined the few great and essential qualities of goodness, to which little need be added, and without 112 Journal of the Mitchell Society [February which all additions or embellishments are as naught. A big-hearted humanity, transparent honesty, quiet and sustained industry — these are the immortal three; but let us also add the salt that never loses its savor, the disposition to enjoy life and to get some fun out of it. It is needless to add that he did not know the meaning of the word vanity, as he had no trace of it in himself. While I was at Johns Hopkins one of the strongest and best young professors in that University died. Dr. Brooks, our great teacher of Biology, who loved this man deeply, said to me: 'He was as simple as a child,' as summing up all that was best in his friend. These words return to me as I think of Wolfe. Such is the simplicity of serenity and harmony, the absence of a jarring note. ''Men of this type, and they are not so numerous, remind us of natural phenomena. They are like the pine woods in winter — un- shaken and sustaining in their perennial verdure. When others change, their colors do not fade. They are like the hills, from whence Cometh our help. There was no uncertainty about Wolfe and no futility. He was radiant with humanity. There was a glow about his friendship and his sympathy that did not admit of question. He was not a casual benefactor, but was full of a sustained gener- osity. Those who were with him daily In his community will testify to his work as a member of the Board of Directors of Watts Hos- pital and of his personal service in cases of sickness and distress. He was willing to give himself, and not merely his means, a most rare and excellent thing in a man. "As a student and investigator, Wolfe was intelligent and faith- ful. His mind was intensely interested in ideas as well as facts, and he was constantly thinking. I always looked forward to his visits with interest. With his full share of jovial conversation, we were never long together before he started a serious discussion of some interesting biological problem of the day. He liked to talk about evolution and heredity, their new problems and phases. This interest was reflected in his choice of a subject for his presidential address before the North Carolina Academy of Science at its 14th annual meeting at Wake Forest (see this Journal, 31: 12. 1915). He was not dogmatic and could change with the times. When a cherished position was undercut by new discoveries he could step off at the right moment. "Among American biologists his position was more than respect able. He stood high as a producer of sound and timely work. He was not wordy, never published for bulk, and was not anxious to appear prolific. His papers were of the kind that required hard and patient labor, and he kept right on until he got the results. His training at Harvard under Farlow and Thaxter gave him a clear conception of what is true scholarship and he never for a moment lowered his standards. True to the best traditions of his profession, he did not loaf his summers away under the plausible pretense of a needed rest, but spent most of them in hard work at the Marine 1921] James Jacob Wolfe 113 Biological Laboratory at Woods Hole, Massachusetts (1901-1906), and at Beaufort, North Carolina, in the laboratory of the U. S. Bu- reau of Fisheries (1909-1916). There he collected and prepared the material for his excellent papers on the biology and reproduction of the seaweeds that brought him his greatest reputation. His work on the algae Nemalion (Annals of Botany 18: 607. 1904) and Padina (see this Journal 34: 78. 1918) would alone place him as an invest! gator of fine abilities. Recently he had been engaged in investiga- tions on the plankton of Chesapeake Bay for the U. S. Fish Com- mission, a considerable part of this work having been completed at the time of his death. In recognition of the importance of this work the Elisha Mitchell Scientific Society invited him to give an address on the subject at its meeting of January 13, 1920. (For abstract see this Journal 36: 3, 1920.) "Wolfe was elected to membership in the North Carolina Acad- emy of Science at its 6th Annual Meeting in 1907 and was an active and enthusiastic member during the whole of its subsequent record. So far as I recall, he never missed a meeting and he nearly always presented a paper — and a good one. As a member of the Executive Committee at various times, as Vice-President (1908-1909) and as President (1914-1915) he gave freely of his time and judgment. In his death the Society has sustained a heavy and irremediable loss. We shall miss him as a friend and as a strong support." "Below is a list of the published papers and addresses of Dr. Wolfe so far as I have been able to find them: Cytological Studies in Nemalion. Annals of Botany 18: 607-630, pis. 40-41, with 1 text fig. 1904. The Cause of Pellagra: a Preliminary Report. Paper presented before the 9th Annual Meeting of the N. C. Academy of Science. Abstract in Journ. E. M. Scientific Soc. 24: 53. 1910. Alternation of Generations in Padina. Paper read before the 12th Annual Meeting of the N. C. Academy of Science. Abstract in Journ. E. M. Scientific Soc. 29: 8. 1913. The Locust Tree Carpenter Moth, a Formidable Parasite of the Oak. Paper read at the 13th Annual Meeting of the N. C. Academy of Science. Abstract in Journ. E. M. Sci. Soc. 30: 65. 1914. An Outline of Modern Work Bearing on the Theory of Descent. Presidential address before the N. C. Academy of Science. In full in Journ. E. M. Sci. Soc. 31: 12-26. 1915. Alternation and Parthenogenesis in Padina. Paper read at 15th Annual Meeting of the N. C. Academy of Science. Abstract in Journ. E. M. Sci. Soc. 32: 51. 1916. Some Methods and Results of a Plankton Investigation of Chesapeake Bay. Witli Bert Cunningham. Paper read at the 17th Annual Meeting of the N. C. Acad- emy of Science. Abstract in Journ. E. M. Sci. Soc. 34: 70. 1918. Alternation and Parthenogenesis in Padina. In full in Journ. E. M. Sci. Soc. 34: 78-109, pi. 1. 1918. (Contribution from the Laboratory of the Bureau of Fisheries, Beaufort, N. C. This paper, in somewhat shortened form, was read Hi Journal of the Mitchell Society [February before a joint session of the Botanical Society of America and the Botanical Section of the A. A. A. S. at their 1918 meeting in Pittsburgh.) New and Little-Known Diatoms from Beaufort, N. C. Paper read before 18th An- nual Meeting of the N. C. Academy of Science. By title in Journ. E. M. Sci. Soc. 35: 11. 1919. The Plankton of Chesapeake Bay. Invitation address before the Elisha Mitchell Scientific Society, January 13, 1920. Abstract in Journ. E. M. Sci. Soc. 36; 3. 1920." His younger colleague in the Biological department of Trinity- College, Professor Bert Cunningham, is able because of an intimate acquaintance of several years, to render an opinion based upon the sure ground of daily intercourse, and a consequent thorough knowl- edge of Dr. Wolfe's character as a man, a scholar and a gentleman. "He was a perfectly frank, straightforward man, always avoiding, if possible, the hurting of another; kind, patient, considering the other man more than himself, and never in any way seeking retalia- tion for wrongs done him; interested in civic welfare, and especially devoted to the relief of suffering. "As a teacher, he was exceptionally well-grounded by knowledge much broader than his field; accurate and exacting in the classroom and laboratory; a leader and stimulator of thought on the part of his students; a personal friend and adviser to them. "As an investigator he was exceedingly accurate and painstaking, endeavoring to get the 'last word' of a subject before laying it down; keen in seeing methods for the attack of problems and in recognizing the relations of a problem to the whole problem of life; and excep- tionally careful in his writing that there might be no ambiguity. " I am incompetent to write a eulogy for this splendid man. Words fail w^hen I try to express my appreciation. To have lived with him and worked with him has been a great opportunity that I shall ever appreciate. To be without his judgment, guidance and friendly counsel is an irreparable loss." His fellow-members of the Academy of Science, recognizing the justice and truth of the testimony quoted, desire to express their concurrence with it, and to render respectful homage to the fine qualities of mind and heart possessed by Dr. W^olfe, together with a keen and sorrowful regret that his useful life should have been so untimely cut off. Integer vitae scelerisquc purus Non eget Mauris jaculis neque arcu Nee venenatis gravida sagittis, Fusee, pharetra. W. H. Pegram, R. U. Wilson, A. H. Patterson, Committee. THE CHEMICAL BEHAVIOR OF ZIRCONIUM By F. p. Venable Any discussion of the chemical relations and behavior of an ele- ment forms necessarily an unfinished chapter in the present state of knowledge. This is particularly true of zirconium, which has been so imperfectly studied, where comphcations are many and their unraveling presents unusual difficulties. It is only by the apphca- tion of the most modern chemical and physical methods that a solu- tion can be hoped for; hence it is not strange that many of the earlier observations were faulty and misleading, and that only partial knowl- edge has been attained as yet. Since there is no positive evidence that the valence of zirconium is ever other than four, there is at least a helpful simplicity in this regard. In the ionization of its compounds two varieties of ions are definitely known, namely, the quadrivalent zirconium Zr and the bi- valent zirconium monoxide ZrO, which has no independent existence. It has been reported that the sesquioxide ion (also bivalent), Zr2 03, has been found under certain conditions, but this has been brought into question by later work. Recently it has been suggested that both the quadrivalent elementary ion and the bivalent zirconyl ion may be present in the same compound. While this is not impossible, it does not appear to be the only explanation of the results obtained. The complex ions have been found by various investigators to migrate with the negative stream as well as with the positive. This, of course, is to be expected in true chemical compounds where one is dealing with an amphoteric element. Sometimes it is doubtless to be attributed to the colloidal nature of the product under examina- tion. Zirconium forms binary compounds with a number of the ele- ments. The evidence is against the existence of a hydride ZrH4. The hydride reported as ZrH2 may contain only absorbed hydrogen. This hydrogen is lost at a higher temperature. Nitrogen combines with the heated element, forming various compounds. This nitrogen is also driven off below 1000°. Compounds with the halogens are stable up to high temperatures and the oxide is dissociated only at the temperature reached in an electric furnace. The oxide Zr02 forms at least two hydroxides. The normal hy- droxide, or zirconium hydroxide Zr(0H)4, is easily hydrolyzed in the [1151 116 Journal of the Mitchell Society [February presence of water. When water is excluded normal zirconium salts can be formed from it. When hydrolyzed, zirconyl hydroxide ZrO (0H)2 is formed. This hydroxide is amphoteric, behaving as a base towards strong acids and as an acid towards strong bases. It shows little tendency to form definite compounds with weak acids or bases. As a base it gives zirconyl salts, and these may be hydrolyzed into basic zirconyl salts. As an acid, called zirconic acid H2Zr03, it forms zirconates, chiefly with the alkalies and alkaline earths. These are very slightly soluble in water and are decomposed by mineral acids. Zirconium shows many and close analogies to the other elements in the fourth group, both as to the compounds formed and their chemical behavior. This analogy is especially close in the cases of titanium and tin when they are quadrivalent. In limitation of val- ence it is more like carbon and silicon. Its occurrence as the dioxide is also characteristic of the group. The ease of hydrolysis and the amphoteric character of the hydroxide are also group characteristics. The outstanding characteristics of the compounds in which tetra- valent zirconium is directly united with an acid radical is their marked tendency to react with water. Ignorance of this or failure to consider it has led to many mistakes on the part of earlier investigators. Older statements represent such salts as the tetrachloride, the sul- phate, the fluoride, and others as crystallizing unchanged from aqueous solutions, but later investigators have shown that none of these salts can exist in water solutions and most of them are unstable in the presence of the slightest moisture. Hydrolysis takes place not merely with readiness, the water pro- duced in a gas burner hydrolyzing normal zirconium sulphate which is being heated by it, but also to a far-reaching extent. The velocity of the reaction and the extent depend upon the dilution, the tempera- ture, and the time. The content of such a solution then is determined by its previous history. The hydrolysis is progressive and the acid radical may be gradually liberated until very little is left in combina- tion, the small remaining portion being held probably by adsorption. In the case of the chloride, for instance, the amount of chlorine left has been found to be about 3 p.c. of the amount originally present, and this is no longer precipitated by silver nitrate unless first treated with nitric acid. When dialyzed this chlorine is found with the colloidal hydroxide in the hydrogel. This hydrogel consists in the main of zirconyl hydroxide. Experiments with the sulphate yield similar results. The normal hydroxide is unstable in the presence of 1921] The Chemical Behavior of Zirconium 117 water, losing one molecule of water and changing to zirconyl hydroxide. It is more easily soluble in acids than zirconyl hydroxide. At various stages in the hydrolysis the addition of ammonium hydroxide will give precipitates of different composition These have been con- sidered by some as new hydroxides, but there is little proof that they are not mere mixtures. It has been suggested that there are two hydroxides with the formula ZrO(OH)2, ordinary zirconyl hydroxide, which is amphoteric, and a metazirconic acid. No salts of the latter are definitely known and its existence has been disputed. While in all cases the hydrolysis is progressive, it is almost certain that all the molecules do not react with water at the same time, and hence at any one time various stages of hydrolysis may be present in a solution. It is common, however, for one of the stages to pre- ponderate. It may therefore be possible to observe definite steps in the progression when there are formed basic zirconyl compounds which either separate by precipitation because of their insolubility or by crystallizing with molecules of water, forming difficultly-sol- uble salts, or otherwise afford indications of their presence through physical tests such as electrical conductivity, thermo-chemical data, cryoscopic determinations, etc. One of the most frequently occuring of these basic compounds is Zr 2030)2, known as Endemann's chloride. Its analogues are Zr203.S04, Zr203(N03)2, Zr203(SCN)2, and others. These have always been obtained in the hydrated condition, and it has been observed that the last portion of the water is removed with considerably greater difficulty. This fact, combined with that of leaving the colloidal hydroxide on dialysis, leads to the suggestion that the formulas be written ZrO(OH)2.ZrOCl2, ZrO(OH)2.ZrOS04, etc. These indicate the degree and order of the hydrolysis. Thus the steps are ZrCl4+H20= ZrOCl2+2HCl; 2ZrOCl2+H20= ZrO (OH)2.ZrOCl2+2HCl. In the first stage all of the tetrachloride is hydrolyzed. In the second, one-half of the zirconyl chloride is hy- drolyzed and the colloidal hydroxide formed either combines chemi- cally with the zirconyl chloride or forms an adsorption compound with it. It is difficult in this and a number of similar cases to con- ceive of these substances where the composition is definite and the conditions of formation are accurately known as other than definite chemical compounds. Thus at a temperature of 39.5° between the dilutions 1: 4 and 1: 120 the sulphate Zr(S04)2 is hydrolyzed with the production of a crystalline substance having the composition 4Zr02.3S04.14H20, which may also be written ZrO(OH)2.3ZrO. 118 Journal of the Mitchell Society [February S04.13H«0. This indicates a hydrolysis in the second stage of one out of four molecules of ZrO.S04. The velocity of this reaction diminishes with decreasing temperature, and it has been found that only 67 p.c. of the sulphate originally used go to the formation of this product. The condition of the remainder in this case is unknown. The crystalline basic sulphate just mentioned and other compounds of like character show partly colloidal properties and have therefore been classed by Hauser as half-colloids. Again, the existence of an equilibrium reached in the hydrolysis is indicated sometimes in measuring conductivity changes. Thus in the case of the hydrolysis of a one-fourth normal solution of ZrOCU. 8H2O at 18° the change for the first sixty minutes is at an average rate of 67 x 10-^ ohms per cc. per minute. For the next 168 hours it averages only 0.014x10-^ ohms per minute, indicating the slow breaking down of a more stable compound or the retarding effect of the liberated acid. This retarding effect of free acid is w^ell known. It can be inhibitory or even cause a reversal of the reaction. Thus the addition of slilphuric acid to a partially hydrolyzed zirconyl sul- phate solution when it reaches a certain concentration will bring about the separation as crystals of the original zirconyl sulphate. Normal zirconium sulphate crystalUzes unhydrolyzed from sulphuric acid containing only a few per cent of water. This inhibitory and reversal effect is produced also by the presence of the salts of strong bases like the alkalies. Anhydrous zirconium fluoride, for instance, is very slowly and difficultly soluble in water. In solution it is hydrolyzed, ZrF4=ZrOF2.H2F>.3H20. This recrystalfizes from water unchanged. If considerably diluted, an amorphous basic zirconyl fluoride is pre- cipitated. This formation of an acid salt with the liberated acid has been noticed in a number of cases. If the water present is in small amount, the hydrolysis is checked. If a salt of a strong base is added (usually in excess) there is formed a double salt or complex which does not hydrolyze. With potassium fluoride three complexes are formed. First, we have KF.ZrF4.H2O, which can be formed only in the presence of a large excess of zirconium fluoride and is decomposed on re-solution in water. It should probably be written KF.ZrOF2. H2F2, lacking enough potassium fluoride to inhibit hydrolysis when much water is added. The second salt, 2KF.ZrF4, crystallizes with- out water of crystallization. It is very stable, giving off hydrofluoric acid only at a red heat, and can be repeatedly recrystallized from water. It is regarded as a salt of fluozirconic acid and, under that 1931] The Chemical Behavior of Zirconium 119 supposition, its formula may be written KaZrFs. It is formed when the potassium fluoride and zirconium fluoride are mixed in equivalent proportions. Zirconium sulphate also affords a very instructive example of hydrolysis. So complicated are the different directions which this hydrolysis takes and so varied are the products formed that it has been the subject of skilled investigation for the past two decades, and many mistakes have been made from the earliest time up to the present. Some of the problems involved still lack a satisfactory solution. The normal sulphate was long supposed to exist in two crystalline forms — the anhydrous, Zr(S04)2, and the tetrahydrated, Zr(S04)2.4H20. The first crystalhzed from concentrated sulphuric acid and its formula is correctly given. The second crystalhzed from aqueous solutions, presumably without change. It has been shown since that the latter is really an hydrolysis product. The hydrolysis proceeds as follows: Zr(S04)2.4H20 = Zr(S04)2+H20+3H20 = ZrOS04. H2SO4.3H2O. Of course, such hydrolysis would not be revealed by analysis. A solution of this acid compound reacts with certain reagents in a manner different from a freshly-prepared solution of Zr(S04)2 and which is only slightly hydrolyzed. If sulphuric acid is added to this fresh solution of zirconium sulphate the same reactions are shown. The mere presence of free acid might serve as an explana- tion without the assumption of an acid compound but would leave the inhibitory effect upon hydrolysis unexplained. Observations based on physical methods also corroborate the view that an acid compound is present. There seems to be no inherent obstacle to writing this formula as a hydrogen zircon yl sulphate, ZrOs— SO4. Similar acid complexes are given with the nitrate, perchlorate, and compounds with certain organic acids. One of the other possible series of hydrolytic changes has also been traced analytically. Zr(S04)2+H20=ZrO(S04)2H2. 2ZrO(S04)2 H2 + H20=Zr 203(804) 2H2+H2SO4. Electrolytic dissociation yields respectively the anions ZrO(S04)2 and Zr203(S04)2. These compounds occur in solution along with strongly hydrolyzed basic zirconyl products, as is evidenced by the composition of the precipitates ob- tained from these solutions on the addition of alcohol. Such preci- pitates are usually poorly defined and seemingly amorphous. It 120 Journal of the Mitchell Society [February has been found possible, however, to obtain by other means a well- defined, crystalline product whose composition is represented by the formula SZrOj.SSOa.HHiO, and a potassium compound, 4Zr02. 5SO3.K2O. The following additional scheme of hydrolysis has been proposed : 4Zr(S04)j + 8H,0 = Zr^lSOOeH* + 2H2SO4 Zr4(S04).. (0H),.H4 + 2HsO = Zr4(S04)6. (0H)g.H2 + 2H,S04 Zr4(S04)». (0H)..H2 + 2H»0 = Zr4(S04),(OH),o + 2H,S04 Zr4(S04)2(OH)„ 2Zr4(S04),(OH)io + 2HiO = ySO* + HiS04 Zr4(S04)j(OH)„ The compounds Zr4(SO4),(OH)8.H4.10H2O and 4H2O have been ob- tained as crystals, and also the compounds Zr4(S04)3(OH)io and (Zr4(S04)2(OH)„)2S04.8HA but the compound Zr4(S04)5(OH)s.H, only in the form of an alkali salt. In preparing these the colloid is removed by dialysis and these half-colloids crystallized from the concentrated solutions. The complex and varying products obtained by mixing a solution of zirconyl sulphate with one of potassium sulphate have long been a puzzle. In part, at least, mixtures of hydrolyzed substances are formed. Recently it has been shown that if the mixed solutions are concentrated over sulphuric acid definite compounds crystallize. These show very well the influence of such a salt as potassium sul- phate upon a progressing hydrolysis. When potassium sulphate is used micro-crystalline needles with the composition K4Zr4(OH)8 (804)5.81120 are obtained. In a solution strongly acid with sulphuric acid the first crystals formed are K4Zr(S04)4; in weakly acid solutions the composition is that of potassium-zirconium hydroxysulphate of varying composition. These products hydrolyze on being treated with water. If boiled with water, they become opalescent with colloidal zirconium hydroxide. Following the crystaUizations in detail, the above-mentioned potassium-zirconium hydroxysulphate K4Zr4(OH) 9(804) 6.8H2O forms a crystalline crust of needles. A second crop of prismatic crystals is formed and this has the composi- tion K4Zr (804)4.51120. The first crystals in hydrolyzing increase the free acid and bring about an equilibrium. The formation of the second then begins and decreases the amount of free acid. The reac- tion is thereupon reversed and the hydroxysulphate crystals form once more. 1921] The Chemical Behavior of Zirconium 121 In the preparation of certain compounds by precipitation methods it has been found that the precipitate forms sometimes only after a considerable lapse of time or upon heating the solution. This is especially the case where weak acids, such as the organic acids, are concerned. The compounds thus formed are found to be more or less highly basic zirconyl salts or mixtures of such. It seems reason- able to infer that the acid radical of the precipitant used formed only soluble compounds with the less hydrolyzed salts and insoluble ones with the more basic. It is possible also that in some cases these are not true chemical compounds but adsorption compounds in which the acid radical has been absorbed by the colloidal hydroxide. Some of these products are distinctly gelatinous and can be washed and filtered with difficulty. On the other hand, some are granular and some distinctly crystalline. The hypothesis of colloidal compounds is especially probable wherever the acid radical can be practically removed or greatly reduced in amount by repeated washings of the precipitate, as is true with iodic acid and some organic acids. When, however, analysis reveals the same basic compound as being formed under varied conditions of dilution, etc., as is the case with the basic chromate, it may fairly be assumed that a definite chemical compound has been formed. There has been little system in the assignment of formulas to the basic zirconyl compounds. Some have written them simply in the ratio of the zirconia to the acid anhydride as 2Zr02.S03. Others report this basic zirconyl sulphate as Zr02.ZrOS04. Perhaps the most common formula is Zr203.S04. Such formulas fail to make clear the known facts. These substances are often gelatinous and, when hydrolysis is far advanced, the solutions become opalescent. On dialyzing the solutions leave zirconyl hydroxide as a hydrogel. Even the crystalline basic salts dialyze with difficulty and show partly colloidal properties. They have been called half-colloids. Elec- trolytic dissociation shows often a migration of the zirconyl radical as an anion or a partition of the zirconium between the anions and cations. It is well known that the migration of a colloid is largely influenced by the medium. Furthermore, there is practically always water of hydration or crystallization present. Considering these facts, it is suggested that the most suitable formula for these basic salts would have to include the zirconyl hydroxide. Thus ZrOj. ZrOSOi becomes ZrO(OH)2.ZrOS04 and Zr203Cl2 becomes ZrO(OH)2. ZrOCh. This reveals at a glance the stepwise formation of the 122 Journal of the Mitchell Society [Februanj colloid and the liberation of the acid, e. g., ZrCl«+H20=ZrOCl2+ 2HC1; 2ZrOCl2+2H20=ZrO(OH)..ZrOCl2+2HCl. Where several molecules of ZrOCU are hydrolyzed at one step more complex prod- ucts will result. This method of writing the formulas has therefore been adopted throughout this text wherever accurate knowledge of the composition of the substance was available. The tetrahalides of zirconium, especially the tetrachloride, form a number of substitution compounds with organic substances. In these all or half of the chlorine may be substituted. Thus acetic acid and its homologues of the aliphatic series give compounds Zr (C2H302)4, or in general, Zrll4, whereas benzoic acid and its homol- ogues give ZrCLCCeH 6.002)2 or ZrCURs. With the esters, ketones, and aldehydes addition compounds are formed. Thus for the ben- zoic ethyl ester compound the formula is ZrCl4(C6H6.C02.C 2115)2. Similar direct addition compounds are formed betw^een ZrCh and the amines, the pyridin bases, etc. The tetrachloride has been suggested as a catalyzing agent in organic synthesis by Fridel and Crafts. Chapel Hill, N. C. A PURE CULTURE METHOD FOR DIATOMS* By Bert Cunningham Plate 9 At the suggestion of Dr. G. M. Smith of the Botany Department of the University of Wisconsin the writer undertook the pure culture of Algae. Among others, the Diatoms proved most abundant, and therefore they were selected as the subject of further work. Beyerinck (1890) seems to have been the first to apply the idea of Koch (1882), i. e., the use of a solid media to the culture of Algae. He succeeded in securing a culture of a protoccoid in a mixture of gelatine and sterile pond water. Miquel (1892) was the first to secure a Diatom in pure culture. He made an artificial nutrient with sterile sea water and inoculated it with a couple of drops of plankton material and then started cultures by fractional subdivision. In 1900 Allen and Nelson used the same method but with a variation of nutrient. West (1916) thought the method of Allen and Nelson to be good but suggested that the materials should be poured into Petrie dishes and, after a few days, the colonies should be pipetted out. Richter (1903-11) secured Nitzschia palea and Navicula minus- cula by the use of synthetic agar plates. His technique will be dis- cussed later. Pringsheim (1912-13) used the agar method for grow- ing and separating of Oscillaria and Nostoc. He mentioned the occurrence of Diatoms but apparently did not follow them up. Returning now to the technique of Richter. This is given in his Zur Physiologie der Diatomeen, published in 1909. In 1906 he started a culture of Diatoms with Fucus serratus and placed them in an atmosphere of hydrogen-sulfid. This reagent killed the bacteria but seemed to have no serious effect upon the Diatoms. This had been previously shown by Molisch. The Diatoms secured in this man- ner were colorless and identified as Nitzschia putrida Benecke. Later, in 1906, he secured pure cultures by dipping a tube in raw cultures, holding it for a minute and then dipping it into sterile sea water. The cultures secured in this way were placed on agar plates. At this time he used also another method. A small piece of agar was suspended in sterile sea water which had been inoculated with a few drops of plankton material. In the course of a few days the diatoms had reached the agar and attached themselves to it. Practically ♦Presented at the Botany Seminar., Univ. Wis., Feb. 1920. [123] 124 Journal of the Mitchell Society [February pure cultures were thus secured. These colonies also were trans- planted to Petric dishes. Such methods might serve well where the great majority of the Diatoms are of one species and where there is no great contamination of other forms, but would hardly be successful when used with the ordinary fresh water plankton. The method which we propose here is based upon these previous methods but has a number of variations. In the first place we used artificial media. It was made after the formula suggested by Moore (as given by Kiister) for the culture of Algae, as follows: Ammonium Nitrate 5 gr. Dipotassium Phosphate 2 gr. Calcium Chlorid 1 gr. Magnesium Sulfate 2 gr. Ferric Sulfate trace Distilled water 1000 cc. (Special low conductivity) This differs from the formulae usually given for Diatoms in that it contains no added Sihcon compound. Chemical analysis of our agar, however, showed Silicon to be present and an examination of the agar filtered through cotton showed the presence of some marine Diatom shells. A 2% solution was now made up with this nutrient and washed agar. The material was sterilized in test tubes and retained in them until needed. It was then melted and poured into Petrie dishes. When it had cooled somewhat, but not hardened, a drop of pond water was placed on it and washed around. The plate was then hardened and was turned up-side-down upon the cover and placed under a bell jar in the green house. After from three to four weeks, there were colonies of various organisms, large enough to be spaded out. This was accomplished by the use of a platinum needle. The colony thus dissected out was examined under the microscope and if not too badly contaminated, it was stirred up in sterile water and replated on new agar plates. These plates were likewise placed under culture conditions and in a few weeks had well formed colonies. In case all the colonies were not of the same species, colonies were dissected out and replated. Thus far this second plating in all our cases, has given us pure cultures. In this manner we have secured four species of Diatoms.* ♦ In tliis manner we secured also a Blue Green, a unicellular Green and Scenedesmus, the latter of which has bee" thoroughly worked out by the pure culture method by (J. M. Smith (1916). The four species of diatoms thus secured have been identified by Dr. J. J. Wolfe as Navicula atomus Naog. Navicula minuscuia Gnm. Nitzschia amphioxijs (Ehr.) Grun. Nitzschia palea Wm. Smith. 1921] A Pure Culture Method for Diatoms 125 Diatoms, as well as bacteria, have, in some cases, well defined contour of colony. Each of the species we have cultured shows a decided difference. The first type is that of a spreading form. It soon comes to cover the entire plate with a film of individuals. A plate of this form is shown in fig. 1. A colony of this type is easy to secure since one has but to dip down between the colonies in an old plate and make cultures from this "dip." Another form of colony is shown in fig. 2. Here we find the colony margin to be restricted and the form more or less radiate, with the organisms rather evenly distributed over the area. A third form of colony is somewhat similar to the latter, but differs in that the central area is much more thickly settled than the margin. This thickened area occurs before the gradual spread as is easily seen from fig. 3. Perhaps the more characteristic form -is that assumed by the last type which, we call the sheaf type. Fig. 4 is of this type. We are satisfied that we have not in any degree studied all the forms that may be cultured in this manner, since a number of forms" were found in the first plates which we did not have time to follow up, and further, our original pond water did not contain a great number of forms. Diatoms cultured in this manner are easily cleaned and prepared for examination. The various colonies are spaded out, placed in a test tube and the agar dissolved in boiling water. The solution is centrifuged with a small centrifuge and the precipitate is washed several times with hot water, the centrifuge being used each time for concentration. After all the agar has been removed the Diatoms may be either burned upon the cover glass or cleaned with sulfuric acid and bichromate. After thorough washing they are kept in 50% alcohol. The pure culture methods open up several fields of work. First, the physiology of a species may be studied as was done by Richter. Second, the classification of the groups may be studied. We think this last point one of great interest. It is fairly well known that species have been made upon the description of a single valve. By this method, if the species will grow on agar, both shells would be available for study and any differences could be noted. Rare forms may be secured. Again, there is probably great variation among the Diatoms, as elsewhere, and probably the majority of these variants would show up in these cultures, thus species could be minimized. If there should be any doubt as to the common ancestry of all the 126 Journal of the Mitchell Society [ February species on a plate, the Barber pipette could be used to isolate a single specimen as the progenitor. While we do not beheve that this method will be available for all species of Diatoms, yet we feel sure that if it is applied to the forms which will grow upon agar, a number of interesting results will follow. Durham, N. C. Explanation of Plate 9. Fig. 1. Photograph of an agar plate of Niizschia amphioxys. Reduced one-half. Fig. 2. Photograph of a portion of an agar plate of Navicula atomus. X20. Fig. 3. Photograph of a portion of a colony on an agar plate of Navicula minus- cula. X50. Fig. 4. Photograph of a portion of an agar plate of Nitzschia palea X20. LITERATURE CITED Beyerinck. 1890. Kultureversuche mit Zoochlorellen, uns. Bot. Zeit., Vol. 48, pp. 725-785. MiQUEL. 1892, 1893, 1898. Recherches experimentales sur la physiologic, la morphologie, et la pathologic des Diatomees. Annales de Micrographie. Dates as above. Miquel 1903, 1904. Le Microg. Preparateur. Allen and Nelson. 1900. On the artificial culture of marine plankton. Journal Marine Biol., Vol. 8, No. 5. KiJSTER. 1907. Kulture der Microorganism. RiCHTER. 1909. Physiologic der Diatomccn. II Mittcilung. Pringsheim. 1912. Kultureversuche mit Chlorophyllfiihrendcn Mikro-organ- ismen. Zeit. z. Biol, der Pflanzen. Vol. XI, 305-332. 1913. Pt. II of above. Vol. XII, 1-108. West. 1916. Algae, Vol. I. PLATE 9 :i'as .^ 1 \r -.'li'^' THE OCCURRENCE OF UNLIKE ENDS OF THE CELLS OF A SINGLE FILAMENT OF SPIROGYRA By Bert Cunningham Plate 10 Wolle in his Fresh Water Algae of the United States first divides the genus Spirogyra into two groups, based upon the condition of the ends of the cells. In case they are rephcate as represented in figure 5 they are placed in one group, while if they are plane as in- dicated in figure 6 they are placed in the other. DeToni^ makes the same distinction. West^ also uses this character as a means of classifi- cation, but adds concerning the former "it (i. e., the replicate ends) is a character which is constant for the species for which it is found, although the ingrowths are not necessarily present at the extremity of every cell in the filament." Since there are no specific cases cited by West, and since the occurrence is not described by Wolle or DeToni, and since the writer has found such a phenomenon occurring, it was thought to be worth noting. The material was collected in the spring of 1917 in an intermittent pool along with considerable Vaucheria. The species may be de- scribed as follows: Cell membrane replicate at the ends in at least half of the cases examined; chlorophyll band single, usually about four turns; con- jugation scalariform; vegetative cell length about 200 mu, width about 25 mu; zygote cell length about 175 mu, width about 40 mu; zygote somewhat spindle-shaped; length 70 mu, width about 35 mu. This follows so closely the description for S. spreeiana Rahb., that the writer places it in this species. The accompanying figures illustrate more clearly than words the phenomenon. Figure 1 is a diagrammatic drawing (in which no effort has been made to represent the shape of the cell or zygote) of a pair of conjugating filaments. Each cell is indicated as it occurred in the filament. Those marked with double arrows are replicate while the others are plane. Those in which we were unable to determine the nature of the end we have indicated by f. Cells preparing to conjugate are indicated by a P. Figure 2 is a diagrammatic drawing ' Sylloge Algarum. 2 British Fresh Water Algae. (1904). [127 128 Journal of the Mitchell Society [February of another pair of conjugating filaments, in which the points are in- dicated as in figure 1. Figure 3 is a microphotograph of the pair of filaments diagrammed in figure 1. This is a water mount. Figure 4 is a microphotograph showing the differences between the ends of the cells. The phenomenon occurs freely in the •collected material and seems to be natural. The writer has made no attempt at explanation of the cause. However, efforts were made to germinate the spores formed but they were unsuccessful. The failure to germinate was most probably due to laboratory conditions. Durham, N. C. PLATE 10 .+! H ^fl O'r lo 0 I, il 1 ri', ; 'U I V'O' '0 — M 2 fy v^^- V a I SOME MARINE MOLLUSCAN SHELLS OF BEAUFORT AND VICINITY By Arthur P. Jacot Plates 11-13. While at Beaufort, N. C, during the summers of 1915 and 1916, the writer took the opportunity to collect what marine molluscan shells were procurable by beach picking. A study of the material thus gathered and of the fragmentary and scattered condition of the literature on the mollusca of this region have led me to present this summary for what possible short cuts it might give future workers on this subject. Four papers on the shells of this region have come to my notice. In 1860 W. Stimpson published a paper, Mollusca of Beaufort, N. C, in the Am. Jour. Sci., ser. II, vol. XXIX, p. 442. When reading his article it should be born in mind that he confounds Cape Lookout with Cape Hatteras. Eleven years later E. Coues included in his Notes on the Natural History of Fort Macon and Vicinity in the Proc. Phil. Acad. Sci., vol. XXIII, p. 120 (131), 1871, a list of the shells of this region. Again eleven years later H. L. Osburn published in the Studies from Biol. Lab. John Hopkins Uni., vol. IV, p. 64, 1887, some interesting Notes on Mollusca Observed at Beaufort, N. C. Then in 1912, H. D. Aller's Notes on Distribution of the More Common Bivalves of Beaufort, N. C. appeared in this Journal, vol. XXVIII, p. 76. Kurtz, Catalogue of the Shells of N. & S. Carolina, 1860, is a list without locahties. Thus this locality is no new field and prom- ises to be one of importance. Beaufort is the mid-most of North Carolina's harbors or outlets to the sea. Situated 10 miles northwest of Cape Lookout and 95 miles northeast of Cape Fear, it is the only outlet for the waters of the ex- tensive sounds lying back of and between these two Capes. Thus two distinct faunal areas are brought in direct contact and an outside or deep-water silt fauna added. The Molluscan fauna of this region is typical of the east coast of the United States and yet is so situated as to receive West Indian as well as northern species. Two distinct faunas are represented, that of the outer beach or sea and that of the sounds or quiet water. The sea fauna is one characteristic of the whole coast of the state, i. e., a hard sand bottom with mud opposite the inlets. The only [129] 130 Journal of the Mitchell Society [February exception to this is the rock breakwaters at the inlet and at Cape Lookout. The sound fauna may be much divided and classified as to depth, salinity, character of bottom, plant association and current. This would form an interesting study once the shell fauna is better known. See also Coues. The following list is a composite of the above mentioned lists and my collecting. The initials (S C O A J) following the name of the species refer to the names of those reporting the presence of that species. The reference below the name of the species is to a good illustration or description. Some of the material collected may be fossil, as indicated. Some of these fossil looking shells are greenish to bluish-black and of a dead to chalky appearance. This may be due to having lived in mud of that color. Shells are similarly dis- colored from Massachusetts southward, especially such species as Anomia simplex, Pecten gihbus, Ostrea virginica, etc. The smaller Gastropods recorded as fossil (not discolored) were thrown on the beaches by a channel dredge which dumped excavated material on the sand bars and grassy flats. AMPHINEURA Chaetopleura apiculata Say. S C O J Dall, U. S. Nat. Mus. Bull. 37, pi. .51, fig. 10. Uncommon, inside, about break-waters. PELECYPODA Solemya velum Say. S C O A J Dall, U. S. Nat. Mus. Bull. 37, pi. 37, fig. 3. Locally abundant, sand flats. Town Marsh behind draw. (See Aller.) Nucula proxima proxima Say. S C A J Md. Geo. Sur., Plio.-Pleistocene, pi. 65, figs. 1-4. Fairly common, in the channels. Leda acuta (Conrad). S C J Md. Geo. Sur., Plio.-Pleistocene, pi. 65, figs. 5-8. Fairly common, sand flats. Bird Island. Yoldia limatula (Say). S C J Dall, U. S. Nat. Mus. Bull. 37, pi. 49, fig. 5 and pi. 56, fig. 1. Uncommon, sand, dredged (Coues); only fragments found. Glycymeris americana (Def ranee). S? J Outline regular, ribs radially striate. Occasional outside, much worn. Glycymeris peclinata (Gmelin). S C J Figure 45. Uncommon to rare, outside, my specimens all fossil-looking. Area occidentalis Philippi. S C J Figures 48 and 17646. 1921] Marine Molluscan Shells of Beaufort 131 Less common than the next (Coues), vice versa J, outer beach. This is the American variety of Linne's A. noae. Three or four smaller ribs between the large ones. Area umbonata Lamarck. C J Figure 56. Occasional, outer beach. This is the American variety of the European A. imbricata. Large and small ribs alternating, somewhat reticulate. Area (Barbatia) reticulata Gmelin. J Figure 13. Two fragments of posterior portion of valve; inside. Area (Noetia) ponderosa Say. S C A J Md. Geo. Sur., Pho. -Pleistocene, pi. 64, figs. 1-6, and figures 51 and 1019. Common, inside and out (see Aller). Specimens very much elongated posteriorly are rarely met. They approach the ancestral form A. limaula Conrad. I have figured one of these speci- mens, figure 54. (See also Coues.) Area (Scapharca) secticostata Reeve. S C J Figures 55 and 119. Occasional, outer beach. My specimens are worn but do not look fossil. Area {Scapharca) ineongrua Say. S C J Figures 52, 53 and 1021. The most abundant of the genus, outside. Area (Scapharca) transversa Say. C O A J Dall, U. S. Nat. Mus. Bull. 37, pi. 56, fig. 2; and figs. 50 and 076a. Fairly common inside. Could some of Coues' A. lienosa have been this species? The name has often been applied to A. secticostata. Area (Scapharca) eanipeehiensis Dillwyn. S C A J Dall, U. S. Nat. Mus. Bull. 37, pi. 56, fig. 16; and figs. 49 and 181. Common, inside. Specimens approaching the elongate South Carolina variety A. atnericana (with 35 ribs), are seldom found. Atrina rigida (Dillwyn). S A J Arnold, Sea-beach at Ebb-tide, p. 432, fig. 1. Uncommon outside, occasional inside. (See also Aller.) This is the long-spined form. Atrina serrata (Sowerby). S C? J Rogers, Shell Book, p. 410, fig. 1. Fairly common on mud flats, commoner outside. Pteria radiata Leach. Reeve, Conch. Icon., Avicula, pi. 6, fig. 10; and pi. 7, fig. 14. One pair of attached valves, 11 mm. along hinge line. Pteria eximia Reeve. Reeve, Conch. Icon., Avicula, pi. 16, fig. 62, and figures 7 and S. Common on sea fan (Leptogorgia virgtdata) in shallow water. Found on parts of the sea-fan which are black and bare of zooids, with the long wing di- 132 Journal of the Mitchell Society [February rected upward and outward so that they look like a dead stump or part of the fan. Although Stimpson and Coues report Pteria cohjmbus (Dillwyn), I was unable to find a trace of it. The material which I have called P. eximia agrees perfectly with Ree\e's A. eximia and the specimens were quite common on the fans. I have been unable to find any mention of this form. If Reeve's name should be preoccupied or subsequently taken, I would call the species P. eximioides. Some of my material has been deposited in the American Museum under Cat. No. 4998. Oslrea virginica Gmelin. S C O A J Md. Geo. Sur., Plio.-Pleistocene, pis. 61-63. Abundant inside, mostly on mud flats, forming extensive banks locally called "rocks." Oslrea equestris Say. S C See Coues. "Abundant; adhering to rocks with Modiola and Mytilus." Pecten {Plagioctenium) gibbus irradians Lamarck. S C J Rogers, Shell Book, p. 411, fig. I. Abundant, outside, inside on sand in the deeper water. Normal number of ribs is 18-20, most common number is 19; rarely brilliant as P. gibbus; prefers open, clear water, and usually a greater depth than P. gibbus. Pecten (Plagioctenium) gibbus gibbus Linne. S C O A J Common, inside on quiet mud flats, west of Fiver's Island. Normal number of ribs is 19-22, most common number is 20, usually brightly colored, shows preference to quiet water. Pecten yiodosus Linne. S C J Rogers, Shell Book, p. 418, fig. 1. Coues reports a beach worn valve; half a fresh valve was picked up on Shackle- ford Bank in August, 1916. Plicalula gibbosa Lamarck. S C J Figures 85. Occasional inside. Lima inflata Lamarck. S C J Rare, inside, largest have a vertical height of 14 mm., the riblets are obsolete through the center of the disc. Live specimens found by Dr. Hyman differ in being relatively stouter, more inflated, broader, and in being cov- ered by rounded, unequal, radial wrinkles. Vertical height, 13 mm. Anomia simplex Orbigny. S C O A J Rogers, Shell Book, p. 419, figs. 4 and 6. Abundant inside. Mytilus (Hormomya) exustus Linne. A J Figures 1, 2 and 3. Common, on breakwaters. Stimpson and Coues report Mytilus cubitus Say {Modiolus citrinus Bolten) probably for this species. They also report Mytilus edulis. Mytilus recuruus Rafinesque. C J PLATE 11 6 Jjt^ 9 II u d* '<» ''*' t»v IS 1^ 21 28 . 19 oV 26 4 29 30 s 34 %ii « '' = , «.ft t' r- STEREUM FRUSTULOSUM. No, 10-i2 [left]. PENIOPHORA ALBOMARGINATA. No. 3849 [right]. 1921] The Thelephoraceae of North Carolina 163 Basidia 4.8-5.5[jl thick, 4-spored, sterigmata very delicate. Cys- tidia oval to club-shaped, set with crystals, imbedded. Spores a clear salmon color, sausage-shaped, 2.5-3.4 x 7.4-9.5[jl. Our No. 4045 when compared with plants in the Curtis Herbar- ium and with others in the New York Botanical Garden Herbarium labelled C. cinereum agreed exactly. Bresadola (I.e., p. 104) gives the spores as 2.5-3 x 8-11[jl, cylindrical and curved. 4045. On bark of dead branch of Crepe Myrtle, January 28, 1920. (Described above.) 4299. On bark of fallen oak limb, May 9, 1920. Spores curved-elliptic, 2.8-3.5 X 7-8.5m. Common on bark of limbs. Curtis (as Corticium). 7. Peniophora mutata (Pk.) Bres. In Bourdot and Galzin, Bull* Soc. Myc. Fr. 28: 399. 1912. Plates 17 and 32 Extensively encrusting the bark, forming large, thickish patches up to 20 cm. or more long and 6 cm. broad; white, then buff or ochraceous-buff, when wet nodulated and veined, but shrinking on drying and becoming plain, the smooth hymenium cracking to show the pure white, fibrous layer below which rarely cracks all the way through. Margin very thin and fading away to a film. Plant about 0.2-0.25 mm. thick, of which about half is the hymenium, the other half the white fibrous layer. Spores white, rod-elUptic, 3.4-4.2 x 10-13. T^ji.. Basidia 7.7-8[x thick. Cystidia very few and scattered, mostly deep in the hymen- ium, a very few at the surface, club-shaped and covered with crystals. This agrees in all respects with Peck's Corticium mutatum. Plants so determined at the New York Botanical Garden are the same as ours, and the careful description of Bourdot and Galzin agrees in all important particulars. They give the spores as averaging slightly longer, 3-5 x 8-16[jl. There is also little doubt that this is P. suh- gigantea (Berk.) Massee, which was described by Berkeley from a collection of Ravenel on Magnolia glauca. Our plants are exactly Uke those distributed by Ellis on bark of Magnoha (N. Am. Fungi, No. 717). Another specimen on beech from Pennsylvania (at the New York Botanical Garden), which looks the same, was determined by Cooke as this. He says it is near Corticium laeve. A collec- tion labelled C. laeve Fr.irom. Society Hill, S. C, on Magnolia glauca by Curtis is identical as is also a plant that Ellis distributed in his 164 JOURNAL OF THE MiTCHELL SOCIETY [February North American Flora (No. 719 as C. laeve on Magnolia). Another from England (Berkeley) has the same appearance. They do not, however, agree with the description of that species by Wakefield (Trans. Brit. Nye. Soc. 4: 115. 1912). 3993. On bark of dead Magnolia iripelala, January 21, 1920. ASTEROSTROMA Effused on rotting wood; soft and spongy; particularly charac- terized by deep brown, stellate cells (cystidia) included in the con- text and making up its greatest bulk; pale, simple, protruding cystidia also present in our species. We include the only species we have found. Asterostroma cervicolor (B. & C.) Massee Plate 34 Extensively effused on very rotten deciduous wood, forming irregular patches up to 8-10 cm. or more wide and long; surface dull, minutely pruinose, pale fawn color when dry, deep dull brown when wet; margin fading out, indistinct, nearly concolorous. Tex- ture soft and spongy except for a crust-like upper layer which may crack a httle when dry, the thick, softer context not cracking. Dis- tinctly but slowly bibulous, and soggy when wet. Plant up to nearly 1 mm, thick. Hymenium 30-35^ thick, fol- lowed immediately by a very dense layer of stellate cells mixed with much granular material, below this a thick, much more open tissue, composed most conspicuously of the large stellate cells which char- acterize the genus. Mixed with these are bits of imperfect, frag- mentary, very slender, hyahne hyphae and granular detritus. In the more open layer there may be a thin, much denser layer just like that beneath the hymenium. Many fat droplets are present in the cells of the hymenium. Basidia projecting about 7-lOtJL, irregularly pole-shaped, about 4-6tJL thick, with four slender, straight sterigmata about 4[jl long. Cystidia broadly spike-shaped, almost colorless, with moderately thick walls, not encrusted, projecting a little farther than the basidia. Stellate cells deep brown, with about 4-12 spine-like arms which radiate from a central point and may be branched but are usually simple; their walls thick to very thick; arms variable in length, run- ning from very short to 82tJi. long. These stellate bodies are evi- 1921] The Thelephoraceae of North Carolina 165 dently of cellular origin and are formed apparently through the development of a single cell. Spores cream with a faint fawn tint in a heavy print, subspherical, angled or slightly tuberculate, 5-6[i thick, 4507. On very rotten oak wood and bark, south of athletic field, July 25, 1920. HYPOCHNUS Entirely resupinate, dry and coriaceous, felt-like or hypochnoid, that is, with the hyphae loosely woven throughout; hymenium even or papillose; basidia simple, four-spored; the spores rough or echinu- late, distinctly colored in most species. The plants are saprophytic on rotten wood, and usually grow on the under-side of logs. Burt records 30 species from North America (Ann. Mo. Bot. Gard. 3: 203. 1916) of which several are mentioned from North Carolina. We are including two species to represent the genus. See also Wakefield, in Trans. Brit. Myc. Soc. 5: 476. 1917; Bourdot and Galzin, Bull. Soc. Myc. Fr. 28: 354. 1912 (as Gleocystidium in part). Key to the Species Treated Color deep red-brown; surface very granular H. atroruber (1) Color rusty brown with margin paler; surface felted H. fuscus (2) 1. Hypochnus atroruber (Pk.) Burt. Zygodesmus atroruber Pk. Entirely effused, thin, of a granular appearance, color a deep red-brown, about argus brown of Ridgway on the surface, the lower interior and the very thin, indefinite, hypochnoid margin a much lighter, honey color. Context of loosely interwoven, frequently branched, clamp-connected hyphae, paler and more delicate in the lower regions, about 4.5[jl thick, reddish and coarser above, about 6-7.5[jL thick; a few large strands next the substratum 15-1 8[jl thick. Spores brown under microscope, subspherical, echinulate, 5.5-7 X 6-7.7[x. Our plants agree with Ellis No. 1390 of his North American Flora (on cedar) and with other collections on pine bark by Underwood, etc., at the New York Botanical Garden. They also agree well with Burt's description (1. c, p. 230). Peck found the type on poplar and Burt does not mention conifers, but all collections we have seen were on pine or cedar. 4692. On pine bark, spring of 1920. 166 Journal of the Mitchell Society [February 2. Hypochnus fuscus Pers. Plate 32 Plant entirely resupinate and not removable as a membrane (Burt says separable), 300-oOOtJL thick, more felted than hypochnoid, ferruginous-brown (dark cinnamon brown with brighter areas of Sudan brown) in center to light gray on the indeterminate margin, a slight vinaceous tint observable throughout or in places. Sections show such a packing of crystals as to make the structure unintelli- gible without the application of KOH (which dissolves the crystals); after such treatment the context is found to be composed of loosely packed, much septate and much branched hyphae 3.7-7.5[jl thick, with clamp connections and bladder-like swellings up to IO-S^jl thick. Hymenium composed of basidia 7.7-25.9[jl, with four curved sterig- mata and a few pointed structures which arise from the bases of the basidia. Spores smoky brown, irregularly angled and spiny, 5-7.4 X 7.4-9.3[x. 4267. On very rotten deciduous wood, April 18, 1920. HYMENOCHAETE Habit like that of a Corticium or small Stereum, that is, forming on dead wood an entirely resupinate crust or with the margin free and projecting like a bracket. Differing from these in the presence in the hymenium of elongated, smooth, dark, spine-like projections (setae) which extend beyond the basidia. Peniophora differs in the colorless cystidia which are usually set w4th warts and crystals, and which may or may not project beyond the basidia. We include but three species to represent the genus. For a full treatment, see Burt, in Ann. Mo. Bot. Gard. 5: 301. 1918. Also see Massee, in Journ. Linn. Soc. 27: 95. 1890. Key to the Species Treated Hymenial surface not tomentose-felted Color a deep rich brown; the margin usually free H. Curtisii (1) Color slate-brown when wet, clay-brown when dry; margin not free H. corrugata (2) Hymenial surface tomentose-felted, at least on the margin; usu- ally rusty or brownish red, the margin paler H. agglutinans (3) PLATE 19 i 1 \ MKNOCliAETE CURTISII. No. 3830. 1921] The Thelephoraceae of North Carolina 167 1. Hymenochaete Curtisii (Berk.) Morg. Stereum Curtisii Berk. Plates 19 and 32 Extensively resupinate on the underside of oak branches and twigs, the free shelving margins extending about 4-8 mm. and form- ing extensive wings on both sides of the branch; dorsal surface of the caps zoned by ridges and colors, inherently fibrous, but not to- mentose, rough, exactly the color of the oak bark (deep gray) except for a pale cinnamon marginal zone. Flesh very thin and cloth-like, quite pHable, not very strong, cinnamon color; distinctly stratified under the microscope. Hymenium a deep rich cinnamon brown (about argus brown of Ridgway) at all ages unless much weather- worn, then paler; velvety from the close-set, short, curled and looped hairs among which are scattered longer and stouter, straight, taper- ing, red spines which project up to 60^. These last are very scattered and are apt to be missed unless several sections are studied. They are dark internally and most show a sheath-like hyaline thickening of the wall, which is most conspicuous below. Spores (of No. 3830) white, smooth, curved, 1.5-2.8 x 6-8.2[x. Not rare on post oak limbs, where it extends as a complete cover over the underside of dead branches for a considerable distance, often several feet. This habit, with the deep, rich color and narrow wings, will easily determine it. 3805. On an oak twig, November 29, 1919. Young plants. 3830. On post oak twigs, December 6, 1919. Photo. 3842. On a fallen oak limb, December 7, 1919. 3843. On a fallen post oak branch on campus, December 7, 1919. 3875. On a fallen oak limb, December 11, 1919. 3899. On a branch of white oak, December 14, 1919. Common on the bark of white and post oaks. Curtis. 2. Hymenochaete corrugata (Fr.) Lev. Plate 32 Extensively effused and entirely adnate and not removable; sur- face tuberculate, dull but not pulverulent, much cracked when dry, color when wet slate-brown with a tint of clay, when dry a lighter clay-brown except for the abrupt margin which is black on its very edge; thickness of entire fructification about 225tx, the cystidia pointed, brown, with a colorless sheath, projecting about 75^1 from the surface. 168 Journal of the Mitchell Society [February Spores white, elliptic, smooth, 3 X 7.3-8.1[x; basidia about 4. Six thick, projecting (including the 4 sterigmata) about 7.5(x beyond the surface. When put in water the hymenium is not wetted, but is finely silvered by a film of air. 4076. On a corticated branch of a deciduous tree, February 4, 1920. Common on bark and wood. Curtis (as Corticium). 3. Hymenochaete agglutinans Ellis Forming circular or elongated patches up to 2 or more cm. across which fuse on touching and also firmly bind together any two branches in contact in its course; growing margin thick and definite, pure white, tomentose, older surface distinctly zoned with brown and brownish red, covered entirely or in all except the older parts with a thin, felted whitish or tan or drab or rich brown superficial coat. Sub- stance firmly leathery, tough, solid, about 500-700[x thick; yellow- ish, except for the red upper layer which is about 75[i, thick, and which is at first covered with the looser, felted, tomentose, paler coat in which are the strong, red, pointed cystidia which project about 37-70[JL above the felt. These are lost as the felt wears away and are absent in the older, smoother parts. Threads of the context about 2.5-3[ji. thick, much branched. Context very compact and solid, resembling a real tissue, but bibulous, at least in the surface layer. No spores or basidia could be found in our collections, and they are not mentioned by Ellis (Bull. Tor. Bot. Club 5: 46. 1874). On drying the margin may become elevated in places, pulling up the upper layer of the bark with it. It does not become truly free as in H. Curtisii. The species is certainly parasitic, at least after get- ting started. 4694. On living branch of buckeye, New Hope Swamp, December 4, 1920. 4743. On living branch of hornbeam. University Station, N. C, January 7, 1921. CORTICIUM Plants forming an entirely resupinate, encrusting, thin layer which is usually leathery and fibrous or hard and brittle, in some cases waxy when damp; hymenium without specialized cells project- ing or included. Spores smooth, or rarely angled, white, or (when fresh) pink. When pink the color of the spores fades soon in the herbarium. Most of the species are saprophytic on wood or bark 1921] The Thelephoraceae of North Carolina 169 or more rarely on the ground and over mosses, etc., but a few are parasitic as e. g., C. Stevensii and C. vagum (see below). We are including C. lilacino-fuscum in Corticium for convenience, as it has only a very narrow reflexed margin, if any. Burt treats it as a Stereum. We include only a few of the numerous North Carolina species. Burt has treated three parasitic species in Ann. Mo. Bot. Gard. 5: 119. 1918. For important papers on the genus see Massee in Journ. Linn. Soc. 27: 117. 1890; Wakefield, Trans. Brit. Myc. Soc. 4: 113. 1913; Bourdot and Galzin, Bull. Soc. Myc. Fr. 27: 223. 1911 (this gives microscopic characters of the French species); Bresadola, Ann. Myc. 1: 93. 1903; Bresadola, Fungi Tridentini 2: 36 & 57. Key to the Species Treated Not parasitic on leaves and twigs of fruit trees. Color deep blackish indigo blue when damp C. caeruleum (1) Color creamy gray with a lilac tint C. lilacino-fuscum (2) Color sordid whitish or cream to pallid yellowish or och- raceous; surface cracking when dry into easily removable, rather chalky scales C. scutellare (3) Color pale flesh both when wet and when dry, cracked when dry; on deciduous woods C. roseum (4) Color of mycelium and context deep orange, of hymenium pale sulphur; growing on grapevines C. Viticola (5) Color pure white, margin pulverulent or hypochnoid C. arachnoidewn (6) Color light slate when wet, yellowish gray when dry; tex- ture wefty and resembling a mold C. vagum (7) Much like C. vagum in color and texture, but spores smaller and hyphae with clamp connections C. subcoronatum (8) Parasitic on apple, pear, or quince and forming a pinkish buff felt on the lower surface of the leaf and also brown sclerotia on the twigs C. Stevensii (9) 1. Corticium caeruleum (Schrad.) Fr. Thelcphora indigo Schw. Plate 33 Forming small or large patches up to 9 cm. long on twigs and small branches of deciduous woods with the bark on; closely applied to the bark, dull, when damp deep blackish indigo blue with more or less gray tint, when dry blackish gray with often only a faint tint of blue; the margin whitish, well defined, irregular. When well grown the surface cracks into many small, unequal areas and has a thickish, 170 Journal of the Mitchell Society [February somewhat tuberculate look. Flesh 180-260[jl thick, a beautiful clear indigo in thin sections except for the outer part of the hymenium, which is suddenly colorless. Spores white, elliptic, smooth, 4.3-5.2 x 8.5-1 l[x. Basidia 6.5-7. 5[JL thick, irregular. The spores sprout very soon in a damp chamber, the filaments coming usually from one side of the distal end. Easily recognized by the color and finely cracked surface. Mas- see's colored figure (PI. 33, fig. 3) does not represent well the color of our plant, but there seems to be no doubt of its identity. Plants in the Curtis Herbarium from South Carolina, Alabama and England are the same. The miscroscopic characters as given by Bourdot and Galzin also agree. 3997. On California privet by President's house, January 21, 1920. 4018. On standing branches of privet and crepe myrtle, January 24, 1920. 4722. On privet in President's yard, December 10, 1920. Common on wood and bark. Curtis. 2. Corticium lilacino-fuscum B. & C. Stereum roseo-carneum (Schw.) Fr. Plate 33 Extensively effused; margin definite, not fimbriate; not remov- able. When wet membranous and soft, pale creamy gray with dis- tinct tint of lilac; when dry shghtly duller and cracking through the hymenium into numerous, rather small areas, showing the whiter context beneath, not tuberculate except over the inequalities of the bark. Entire thickness about ISS^l; the context composed of rather loosely woven, clear threads, 2.4-3. 5[j. thick, with clamp con- nections and many crystals. In the hymenium are numerous slender paraphyses with short branches near their ends. Unfortunately our figure shows only one and that not branched. Basidia 6.3-7.5^ thick; up to 30[x long, 4-spored. Spores white or pale cream, smooth, elliptic, 3.8-5.5 X 7-9.3iJi, easily collapsing. Our plants agree with plants so named from Ellis (N. Am. Fungi, No. 515), and with Burt's description and figure of Stereum roseo- carneum. In treating this as a Stereum, Burt is no doubt right, but for convenience we retain it for the present in Corticium. 4071. On bark and wood of an oak limb, February 4, 1920. 1921] The Thelephoraceae of North Carolina 171 3. Corticium scutellare B. & C. Plate 34 Extensively effused on corticated or decorticated wood, cracked into innumerable small areas, inseparable as a whole, but when dry the upper, rather friable and chalky part is easily removed from a thin white layer covering the wood; color varying from sordid white through cream or clay to pallid yellowish or ochraceous; obscurely nodulose; margin fading quickly out to a thin granular-looking edge, not byssoid. Entire plant about 148-260[jl thick; hymenium about 65-7-5[jL, no cystidia. Clearing with potash shows a dark, dense layer of about the same or greater thickness beneath the hymenium, and a thinner, more delicate, pale layer next the wood; hyphae delicate, 2.5-3.5ijl thick. Spores long-elliptic, 4 x 7.5-9.3[x. Basidia slender, long-clavate, about 7.4[x thick, with four long sterigmata. This matches well with a collection from Bresadola so named at the New York Botanical Garden, and agrees well with the original description (Grevillea 2: 4. 1873). 4043. On a very rotten but partly corticated branch of Aesculus octandra, Janu- ary 21, 1920. 4223. On bark of oak wood, March 27, 1920. Spores subelliptic, 4.4-5.1 X 9.3- 10m. 4696. On bark of Hmb from a deciduous tree (birch or cherry), December 4, 1920. Spores (print) subelliptic, some slightly curved at mucro end, hyaline, 3.7-4.5 X 7-9m. Common on bark of limbs. Curtis. 4. Corticium roseum Pers. Plate 33 Plant effused, arising as small patches which fuse on meeting without leaving a trace of the line of junction; margin definite and at times a little uplifted, furnished with a very narrow white fringe of fine fibers when growing; surface smooth, dull with the appear- ance of fine felt, pale flesh color both when wet and dry, cracked when dry, the cracks reaching nearly to the substratum, but usually showing at the bottom the white fibers of the subiculum; 140-280^1 thick; threads of context not densely packed, 2.8-3.8[x thick, with clamp connections. Hymenium dense, about 50[i thick, composed, in addition to the basidia, of crowded, much-branched, more or less contorted threads, the tips of which extend above the general sur- face and help to give the pruinose appearance. 172 Journal of the Mitchell Society [February Basidia 4-spored, long club-shaped, about 1 .b\j. thick and project- ing about 40-50(x; sterile cells of much the same appearance are scattered among them and may be young basidia. Spores (of No. 4703) clear salmon, smooth, elHptic, 5.5-7.5 x 9.3-13ix, granular, sprouting over night in a damp chamber. Our plants agree perfectly with a collection of C. roseum from Bresadola at the New York Botanical Garden and with collections so named at Washington. Dr. Burt has seen our No. 3981 and de- termined it as C. roseum. 3981. On decaying hickory tree, Januarj^ 18, 1920. Hyphae delicate, clamp- connected, 3-4m thick. Spores smooth, subelliptic, 4.5-6 X 10-15m. 4703. On bark and wood of branches of Salix sericea, Glen Burnie Farm, Decem- ber 5, 1920. 5. Corticium Viticola (Schw.) Fr. Plate 33 Plants appearing as small, irregular patches with deep orange- red centers and paler byssoid margins which extend and fuse to form elongated crusts up to 2 or more cm. long and 1 cm. wide. Hymen- ium forming irregularly and at times in scattered patches, again continuous, pale sulphur yellow, with the appearance of fine leather, about 45-50[jL thick; the substance below about 185-250[x thick and composed of very loosely woven, rather even threads about 3-4^1. thick, without clamp connections, which are usually a deeper, more orange color. Spores white, smooth, elliptic, with one side flatfish, 5-5.5 X 8.5-9.4tx Among the layers of the bark run deep orange rhizomorphic strands with byssoid fringes which connect with the superficial part. 4693. On dead bark of a live grapevine, New Hope Swamp, December 4, 1920. Middle and upper districts on bark of grapevines. Curtis. 6. Corticium arachnoideum Berk. Plates 17 and 33 Effused irregularly over area of several centimeters, closely ad- herent, color pure white; margin indistinct and pulverulent or hypoch- noid, in center thicker and smooth, and in most places minutely powdery, having the appearance of a thin white-wash. In section about 111^ thick; context made up of very loosely packed, clamp- 19S1] The Thelephoraceae of North Carolina 173 connected, incrusted (so as to look very rough-walled) hyphae, 4.2jx. thick; hymenium about 18[j. thick, made up entirely of young and old basidia, which are clavate, 4:.8[l thick, with four minute sterig- mata; no cystidia, but at base of the hymenium is a layer of crys- tals which KOH does not dissolve entirely. Spores white, short-elliptic, hyaline, 2.5-3.5 X 3.8-5[jl. When compared with specimens of C. arachnoideum from New Jersey (Ellis and Everhart, Fungi Columbiana No. 309) at New York Botanical Garden, our plants agreed exactly and Dr. Burt has kindly confirmed the determination. 4235a. On very rotten, decaying, deciduous wood, March 25, 1920. Common on wood and bark. Curtis. 7. Corticium vagum B. &. C. Corticium hotryosum Bres. Ann. Myc. 1: 99. 1903. Plate 33 Entirely resupinate, pulverulent-looking, margin indeterminate; easily separable from the substratum when wet, and with an open wefty structure that resembles a mold; color when wet, hght slate, drying to a yellowish gray. Structure in section about 240ex thick, consisting of very loosely packed, very large (7.4[x thick,) consider- ably branched, frequently septate hyphae without clamp connections which are yellowish towards the substratum. Spores subeUiptic (flat on one side, curved on the other), pointed at each end, 3.8-5.5 x 7.5-1 l[x. Basidia simple, very pecuhar, hardly distinguishable from the hyphae and not forming a distinct hymenial layer, 7.4-9 X 18-25[jl, with two, four or six curved sterig- mata. No cystidia. The small group of Corticiums to which this species belongs is pecuhar in the undifferentiated condition of the fruiting surface. There can scarcely be said to be a hymenium any more than in a mold. The plant is at times parasitic, again saprophytic. Burt (1. c.) has studied it along with two other related species and his description agrees substantially with ours. Hypochmts Solani, Corticium Solani and Rhizoctonia Solani are the same as this. Our plant also agrees in all important particulars with Bresadola's de- scription of his species and with the more detailed description by Miss Wakefield (Trans. Brit. Myc. Soc. 4: 117. 1913). 174 Journal of the Mitchell Society [February 4230. On bark of a dead poplar limb, April 4, 1920. 4236. On inside of decaying poplar log, April 15, 1920. Spores pointed, sub- elliptic, 3.7-4.5 X 8.5-11. 5m. 4259. On bark and wood of dead pine, April 15, 1920. 4276. On dead pine wood, April 20, 1920. 8. Corticium subcoronatum v. Hoehn. and Litsch. Adnate, thin, pulverulent-looking, so loosely woven as to be lacunate under a hand lens, when wet slate colored, drying to whitish gray; margin indeterminate. Structure in section after application of KOH about QO^x thick, made up of extremely loosely packed, much branched, clamp-connected, hyaline hyphae 5.5-7.4^ thick; no de- finite hymenial layer present but basidia are borne on the tips of much branched hyphae at outer surface and the large number of collapsed basidia give the appearance of a layer of crystals; basidia 6.6-7.4 X 12.5[i,, with four sterigmata and not distinguishable from hyphae except for the presence of sterigmata. Microscopic appearance like C. botryosum, but differing in sec- tion in that the present plant has more delicate hyphae which are not yellowish at base as in C. botryosum, and has clamp connections at septae and smaller spores than the latter. See Wakefield in Trans. Brit. Myc. Soc. 4: 118. 1913. 4271. On bark of very rotten oak log, near Meeting of the Waters, April 18, 1920. 9. Corticium Stevensii Burt. While we have not found this in Chapel Hill, its frequent presence in the mountain region of this state and its importance as a parasite of apples, pears, and quinces leads us to include it here. We adapt the following condensed description from Stevens and Hall (Ann. Myc. 7: 49. 1909, as Hypochfius ochroleucus) and from Burt ( 1. c, p. 125) : Fructification forming a felty, dull pinkish buff, easily i-emovable membrane on the under side of the leaf; hyphae 4.5-7.5[x thick, not nodose septate, bearing the basidia scattered along them on short lateral branches; basidia 7-8 x \\^, with 4 sterigmata; spores hyahne, flattened or slightly concave on one side, 3-4 x 8-11^. The vegetative mycelium lives on the twigs and forms there chestnut-brown Sclerotia from which rhizomorphic strands run to the leaves and are dissipated into the fructifying hyphae. 1921] The Thelephoraceae of North Carolina 175 Stevens and Hall report the fungus from numerous places in west- ern North Carolina where it does much damage to neglected orchards. The species is evidently related to C. vagum, and a true hymenium is absent. STEREUM Plants growing on wood in all species here treated; thin, flat, tough and leathery, or more woody and rigid; petal- or bracket- shaped; in our species usually growing horizontally with a broad attachment directly from the wood or from a more or less extensive resupinate portion; dorsal surface often velvety or hairy, concen- trically zoned and radiately strigose or rugose; hymenium quite smooth and not furnished with sterile spines (setae) projecting among the basidia, but cystidia or paraphyses may be present; basidia simple, spores smooth in our species, nearly white to pale smoky flesh color in a good print. Some species exude a colored juice from the wounded hymenium when in a growing condition. Burt has recently pub- lished his monograph on the American species in Ann. Mo. Bot. Gard. 7: 81. 1920. He records twenty species from North Carolina (including *S. fuscum), two of which we are treating under Peniophora and Corticium. Two of these North Carolina species grow on the ground, both reported from the mountains. See also Massee, Journ. Linn. Soc. 27: 158. 1890. I am under obhgation to Dr. Burt for having determined a number of my plants. For interesting remarks on *S. abietinum Pers. see N. Y. Sta. Mus. Bull. 219, 220, p. 54, con- taining Report of Director for 1918. 1920. Key to the Species Treated Plant forming small tuberculate bodies like crowded molar teeth; hymenium with many warted cystidia S. frustulostwi (4) Not as above. Hymenium becoming reddish when bruised. Growing on frondose wood; surface tawny S. gausapahim (1) Growing on frondose wood; surface blackish with rusty margin; texture hard and woody when dry S. subpileaium (3) Growing on pine; surface pallid S. sanguinolentum (2) Hymenium turning dark brown when bruised S. fuscum (10) Hymenium not becoming red or brown when bruised (S. subpileatu7n and S. fuscum, in which the hymenium changes color when bruised are included below, as this character is obscure except when quite fresh.) 176 Journal of the Mitchell Society [February Dorsal surface grayish, zoned, coarsely hairy S. fasciatum (5) Dorsal surface grayish, zoned, tomentose; plant small, growing on cedar S. rameale a form (7a) Dorsal surface in large part smooth and shining; chest- nut or lighter reddish-brown, tomentose at base and at times on some of the zones aS. rameale (7) Dorsal surface satiny-tomentose, with zones of tan, cin- namon, reddish-brown, etc S. lobatum (6) Dorsal surface smooth, silky-shining, pale tan to whit- ish. S- sericeum (8) Dorsal surface white when dry and densely woolly hairy all over; hymenium golden yellow when dry; plant small S. ochraceoflavum (9) Dorsal surface dull brown, subtomentose on the whitish margin; flesh spongy S. fuscxim (10) Dorsal surface smoothish or more or less scurfy-tomen- tose, particularly towards the margin; deep purplish brown or blackish, margin tawny when growing S. subpileatum (3) 1. Stereum gausapatum Fr. S. spadiceum Fr. Plates 20 and 35 Plant laterally sessile forming a complicated mass of branched, wavy, imbricated, horizontal caps which project a distance of about 1.5-5 cm.; a compound group at times extending laterally up to 8-9 cm. Dorsal surface zoned frequently with ridges and prolifera- tions, densely matted tomentose all over; color when damp dull tawny with brownish zones, the margin reddish brown (where the reddish flesh shows through the thinner tomentum), when dry all parts are a clearer tawny or buffy tawny except for a narrow reddish margin. Hymenium wavy and undulating to form radial ridges, when damp dull dark brown with a tint of bay, the marginal part for about a cm. being reddish ochraceous; all parts of the hymenium turn instantly dull red when bruised and emit a little reddish latex. When dry the hymenium becomes a somewhat lighter dull smoky buff or tan with a faint fleshy tint. Flesh when wet very tough and pliable, about 0.5 mm. thick, deep reddish brown, the hymenium about 0.4 mm. thick (unusually thick for a Stereum) and the tomen- tose coat about 0.6-1.4 mm. thick; tasteless and odorless. When dry the caps are rigid and rather brittle. Spores (of No. 4110) pale creamy flesh, smooth, elliptic, 2.5-3.7 x 6-8.5[x. PLATE 20 STEREUM GAUSAPATUM. No. 3821. 1921] The Thelephoraceae of North Carolina 177 Not rare on rotting oak stumps and logs. The species is easily- recognized by its good size, complicated structm'e, tawny and tomen- tose surface and dark hymenium which turns red at once when bruised. It differs from S. sanguinolentum in tawny color and growth on oak. The latter is pallid and grows on pine. 334. On the base of a rotten oak stump, October 4, 1908. 3821. On oak log at "Long Bridge," December 5, 1919. Spores 3-3.8 X 6-8.2^. 3912. On dead oak log by Battle's Branch, November 5, 1919. 4110. Oak limb by Battle's Branch, February 13, 1920. Common on trunks and stumps. Curtis Blowing Rock. Atkinson. South CaroUna, Hartsville. Coker. 2. Stereum sanguinolentum (A. &. B.) Fr. Plate 35 Largely resupinate, the upper margin reflexed and bracket-like, in our plants extending only about 4-5 mm.; surface of the free caps inherently fibrous, radiately striate, zoned lengthwise by thin brown lines, the remainder nearly white or brown, the thin margin white; flesh leathery, tough, elastic, thin. Hymenium more or less wrinkled and ridged, when young whitish (very pale fawn) sooner darker through light fawn to dusky fawn; when bruised in the fresh state immediately exuding a deep red juice which stains the surface, later the stained parts becoming dark dusky brown with only a tint of red. Spores (of No. 3967) white, sausage-shaped, 2-3 x 6-8.5[jl. Easily distinguished from others that turn red by growth on pine and different color. Our plants form patches about 1.5-2 x 1.5-4 cm., some with and some without the narrow reflexed margin. If soaked again after drying the hymenium turns red almost all over and on drying again darkens to a very deep brown, the margin only remaining white. 3967. On a pine log, January 17, 1920. Photo. Low and middle districts on pine trunks. Curtis. 3. Stereum subpileatum B. &. C. Plates 21 and 35 Plants bracketed from a resupinate layer, extending about 1.5-5 cm. or more, often anastomosing and contorted; dorsal surface vel- vety-scurfy when young and more or less persistently so, the older 178 Journal of the Mitchell Society [February part often quite smooth; multizonate, the more conspicuous zones with obscure ones between; usually crimped and waved to form radiating ridges like an oyster or pecten shell ; color on younger grow- ing margin buff -tawny, then dull tawny-brown or at times abruptly blackish-brown, with dull purple zones and often deep gray zones near the margin. Flesh about 0.5-0.8 mm. thick, very hard and woody, not at all pliable when dry, composed of four distinct layers, the lower, just under the pale hymenium, thickest, ochraceous buff color, with vertical fibers and distinctly stratified in old plants (this rep- resenting the different layers of old hymenium) ; the next layer thinner (unless plant is young) and lighter with horizontal fibers; the next thinner still and black or nearly so and hard and shining like rosin; the upper brownish and densely spongy; threads of flesh densely packed, 3-4[x thick, without clamp connections. Hymenium smooth, pale creamy flesh color, cracking in age, often wrinkled and nodu- lated and obscurely zoned, becoming dull brownish red when bruised in the fresh state. Spores (of No. 3828) smooth, white, oval, 2.5-3.7 X 3.8-5.5[x. Cystidia numerous, encrusted, blunt, about 5.2-7.5[i, thick, pro- jecting about 7.5-1 1[JL — a few bottle-brush paraphyses were seen in our preparations. The caps are perennial, the new growth arising from the lower layer of flesh only, and forming a new hymenium over the old one. Old plants may be practically black and the old hymenium may become straw color or dull creamy yellow with discolorations due to black or green molds. It is not often that one finds plants in so fresh a condition as to show the change to reddish in the hymenium, but the plant is easily determined by its other characters. Rare at Chapel Hill; apparently more common in the Coastal Plain. Our plant is just like S. suhpileatum B. & C, as represented by No. 219 in the Ravenel Exsiccati. Stereum sepium is very near, but is separated by Burt on account of the abundance of bottle-brush paraphyses. Stereum insigne also differs in having many such para- physes and in the absence of cystidia. Stereum rugosum has been considered in a different section on account of the red juice in its hymenium, but in our collections of S. suhpileatum the hymenium also turns red when bruised, a fact which has not been mentioned by others. There is, however, no obvious juice in the latter. 2837. On an oak log, September 23, 1917. 3828. On the same log as No. 2837, December 6, 1919. PLATE 21 "i-as-i * jIT' \\ f ./' ""ijk 4^ >t ■J*' STEREUM SUBPILEATUM. Nos. 1522 and 2837 [above]. STEREUM FUSCUM. No. 689 [center]. STEREUM RAMEALE. Nos. 3813 and 3825 [below]. 1921] The Thelephoraceae of North Carolina 179 3955. On a standing dead white oak, January 17, 1920. Common on log.s and stump.s. Curtis. Blowing Rock. Atkinson. South Carolina. Hartsville (No. 1522.) Coker. 4. Stereum frustulosum (Pers.) Fr. Plates 18 and 35 Plant forming small flat, tuberculate, usually crowded bodies which are somewhat expanded at the top. The upper, spore-bearing surface is usually grooved and uneven hke a molar tooth, is brownish- gray in color and nearly glabrous. The sides are blackish brown and rugosely zoned. Flesh brown, very hard and woody, about 1.5-3 mm. thick, zoned, each zone representing a renewed growth added over the hymenium of the preceding growing season as in Fomes. Spores white, smooth, oval, 2.5-3.5 X 4-5.1[jl. Basidia club- shaped, 5.5-7[x thick, with four very long sterigmata. Cystidia numerous, club-shaped, covered over the distal half with close-set short spines like a giant's club. These spines are not so long in our preparations as in figures by Burt (1. c, p. 227). (See also Lloyd, Letter 51, fig. 565; and Myc. Notes No. 49, p. 696, fig. 1041. 1917.) These peculiar cystidia, together with the perennial habit, indicates a relationship with S. suhpileatum which is, I think, related to S. rugosum. The plant is common on decorticated, but still sound and hard oak stumps and logs. Plants in cavities and unexposed to weather may be buffy brown in color, and some of these at least are sterile. As they grow older the plants expand slowly above and if on ver- tical wood may become shghtly shelving above, in such case looking very like a miniature Fomes. 332. On hard dead wood of white oak, October 4, 1908. 389. On hard dead oak trunk, October 20, 1911. 1042. On stump of Liriodendron tulipifera, December 6, 1913. Photo. 3814. On oak stump, December 3, 1919. 4127. On oak stump, February 15, 1920. Plants up to 3 mm. thick, with as many as ten layers. Low and middle districts on wood and stumps. Curtis. Blowing Rock. Atkinson. 180 Journal of the Mitchell Society [February 5. Stereum fasciatum (Schw.) Fr. Plate 22 Plants very thin, tough and phable when fresh, rather brittle when dry, sessile, and attached by a narrowed base, often imbri- cated, individuals reaching a width of about 8 cm., the upper surface covered densely with a rather harsh, fibrous tomentum; color light creamy gray or grayish tan, with distinct, rather closely set zones. After maturity the upper surface soon becomes green from the growth there of the alga Pleurococcus. Hymenium smooth, faintly zoned and of a hght fleshy-cream color. Spores (of No. 3815) smooth, elliptic, 2.1-2.9 x 5.1-6.5[jl, just like those of S. lohatum. The plant is very common on logs and stumps and may occur in such abundance as almost to cover a large log. It is not rarely intermixed with Coriolus versicolor. The caps are only about a quar- ter to a half mm. thick. The plant is easily recognized by the strigose- hairy cap, hght hymenium and comparatively large size. It is often referred in American herbaria to *S. hirsutum. 938. On an old rotting log by Fern Walk, September 14, 1913. 3815. On dead, deciduous twigs and bark, December 3, 1919. 3820. On rotting oak, December 5, 1919. Common on trunks and limbs. Curtis. 6. Stereum lobatum Kunze. Plates 22 and 35 Plants about 1.3-5 cm. broad, sessile and attached by a narrowed base, petal-shaped and often fused laterally, surface conspicuously zonate with varying shades of light tan, cream, deep reddish brown, cinnamon, etc. Most of the surface is covered with a thick, close interwoven tomentum of satiny texture, but narrow zones on or near the margin may be free from it. Texture pliable when fresh, less pliable and rather brittle when dry, very thin. Hymenium smooth, faintly zoned; color a light fleshy salmon or fleshy tan. Spores (of No. 3816) smooth, white, elliptic, 2.2-3 X 5-6. 5[x, like those of S. fasciatum. This species is about as common as S. fasciatum which it resembles closely in shape, colors and texture. It averages smaller than that species and may be distinguished best by the interw^oven, feltish PLATE 22 STEREUM LOBATUM. No. 3816 [top]. STEREUM FASCIATUM. No. 3815 [center and below] 1921] The Thelephoraceae of North Carolina 181 surface layer, which is not strigose hairy. Stereum versicolor Swartz, to which authors have referred this species, was collected in Jamaica and has a smooth surface (Lloyd, Myc. Notes 33: 429. 1909). My plants have been seen by Burt, who determines them as above. 33] . On dead wood, September 25, 1908. 3816. On dead deciduous twigs and bark, December 3, 1919. Common on trunks and limbs. Curtis. Hartsville, South Carolina. Coker. 7. Stereum rameale Schw. S. compUcatum Fr. Plates 21, 23 and 35 Caps small, shelving from a more or less resupinate base, petal- shaped or shell-shaped, often fused laterally, usually projecting 3-17 mm.; surface zoned, smooth and silky-shining except near the base where it is covered with white, gray or tawny fibers, or the hairs may occur on some of the zones more than half-way to the margin, or very rarely all over; color when quite fresh and damp a light och- raceous on margin, passing through ochraceous to reddish ochraceous at base, when dry a deep chestnut brown with paler zones, or when old. and weathered the color may fade to much lighter. Hymenium smooth, strong, uniform ochraceous when fresh and damp, changing to a creamy flesh color when dry. When on horizontal branches the under side of the branch may be completely covered by the resupinate part, which gives rise on the sides to a long fringe of the projecting caps. On drying the plant contracts so much that the resupinate portion is often split and torn. Spores (of No. 3863) faint smoky flesh-color in a good print, smooth, rod-elliptic, 2-2.8 X 5-7^1. Hymenium (of No. 3802) about 35[JL thick. When damp the hymenium also is faintly zoned but when dry it is not zoned. The dorsal surface is on the contrary more con- spicuously zoned in the dry state. A very pretty little plant which often occurs on small twigs and wings them on both sides if they are horizontal, also appearing in large numbers on larger branches. 333. On a dead oak branch, January 14, 1909. 362. On branches and small twigs, October 11, 1911. Tawny tomentose all over. 3813. On a dead oak limb, December 3, 1919. Spores 2-2.8 X 5-7.2m. 3825. On deciduous twigs, December 3, 1919. Hymenium strong orange salmon. 4106. On an oak twig, February 13, 1920. 182 Journal of the Mitchell Society [February 4174. On a corticated oak branch, February 23, 1920. Color of damp hymenium about gold; grayish flesh when dry. Also man}- other collections on oak, sumac, ironwood, privet and peach. Blowing Rock. Atkinson. Common on dead limbs (as S. complicatum). Curtis. 7a. Stereum rameale. Form on cedar. We have in Chapel Hill a form on Juniperous poles which differs from the typical in the much grayer and more tomentose surface in the smoky hymenium, and in never reaching the larger sizes often found in the latter. These differences remain constant from year to year, but as the spores and other microscopic , characters are the same, I agree with Dr. Burt, who has seen my plants, that it is best to refer them to S. rameale. A description follows: Shape and size as in smaller examples of the typical form, mostly petal-shaped and attached by a constricted base, projecting about 4-8 mm., at times largely resupinate, often in rows; dorsal surface light brown when damp with narrow zones of blackish brown, the margin white or black; scurfy tomentose nearly all over (a few nar- row glabrous zones are present at times); radially channelled; when dry pale gray with narrow blackish zones and an obscure cinnamon tint towards the margin. Hymenium uneven, smoky brown to smoky buff when damp, when dry smoky gray, the marginal part darker. Spores exactly like those of *S. rameale, smoky flesh color, 1.8- 2.8 X 5-6.6[x. Stereum radiatum Pk. which also grows on conifers (hemlock and spruce) in the northern states is very different. 4026. On cedar poles with bark on, January 24, 1920. 4318. Same spot as No. 4026, June 20, 1920. 8. Stereum sericeum (Schw.) Sacc. Plate 35 Plant arising from a little tubercle and, if beneath a branch, largely resupinate by fusions, reaching a length of 6 or 7 cm., the free and shelving margins not continuous but discrete and forming separate petal-like brackets which vary from very small up to 2 cm. broad and extending 1.5 cm.; often not resupinate and attached directly to the wood by a point. Dorsal surface smooth, silky- PLATE 23 STKREUM RAMEALE. No. 4106. 1921] The Thelephoraceae of North Carolina 183 shining, pale straw or whitish gray, radially striate, transversely zoned by narrow lines of brown. Hymenium pale fleshy-straw color to whitish, faintly ridged radially. Flesh very thin, hardly a fifth of a cm. thick, when damp very soft and pliable like softest leather, when dry subrigid and elastic. Spores (of No. 3962, Hartsville, S. C.) pale flesh color in a good print, rod-elhptic, 2.2-3.4 x 7-10[i, a few up to ll^i.. The plants arise from points and if resupinate spread out and fuse when touching, forming a faint line on the hymenium to show the line of union just as in Eichleriella Leveilliana. The point of origin is indicated by a small central nipple in the center of each component part. The species is easily distinguished by the quite smooth, silky, pale caps, small size, and thin, papery structure. In age the plants often become split radially into narrow frayed strips. Rather com- mon. 1043. On dead branch of Carpinus, December 6, 1913. 4040. On blackgum twig in Arboretum, January 26, 1920. Hartsville, South Carolina. Several collections on black gum (Nyssa), December, 1919. Coker. 9. Stereiim ochraceoflavum (Schw.) Curtis Plate 35 Plants typically cup-shaped or elongated cup-shaped, if hanging then attached by a broad base or if on small twigs by an elongated line; if on upright branches then broadly attached by a resupinate side of the cup, size varying from quite small up to about 1.5 cm. broad, or several may be fused to make a length up to 3 cm. Dorsal surface densely woolly-hairy all over, when damp dull white with narrow straw-colored zones towards margin and deeper reddish och- raceous zones near the base, when dry white all over (due to the colored flesh not showing through the white hairs). Hymenium somewhat uneven, of a beautiful golden-yellow color when dry, a more ochraceous yellow when wet; not changing when cut; after some exposure the color may fade to a paler buff. Texture tough and very pliable, like soft leather when wet, sub-rigid when dry; flesh about the color of the hymenium, both together hardly a half mm. thick. Spores (of No. 4033) white, elHptic, smooth, 2-3 x 5.5-7 A\i. A striking and unique plant, easily recognized by the small size, golden-yellow hymenium and woolly-white cap. This is certainly 184 Journal of the Mitchell Society [February S. ochraceoflavum. I have compared a good collection of that spe- cies from the Schweinitz Herbarium and another from Schweinitz in the Curtis Herbarium, and find them identical. It is also like plants under this name in the Curtis Herbarium from Massachusetts, New York and Mississippi. The same thing from Alabama, South Carolina and Cuba in the Curtis Herbarium was labelled S. hir- sutum. Specimens of the latter from Europe are quite different. Our plant is also like S. ochraceoflavum as represented in the Kew Herbarium, where I sent some of my plants for comparison. Stereum sulphuratum B. & Rav. (Journ. Linn. Soc. 10: 331. 1868) seems very near. From the description the species would hardly be connected, but the type of S. sulphuratum in the Curtis Herbarium from Cuba, as well as a collection from Georgia, can scarcely be distinguished from our plants with a hand lens. Burt finds the microscopic characters of the two species to differ in several respects. 2941. On dead twig of Rhus copalina, October 8, 1917. 4033. On twigs of a deciduous wood, January 25, 1920. 4738. On a dead vine of Vitis, December 16, 1920. Common on limbs. Curtis. Hartsville, S. C. On twigs of various deciduous woods as black gum, Ilex glabra, etc., December 25-26, 1919. Coker. 10. Stereum fuscum Schrad. S. hicolor Pers. Plate 21 Caps from 1-2.5 cm. wide, much fused and folded and rising from a common resupinate stratum; surface grayish snuff color, the margin abruptly pallid; tomentose when young, the tomentum col- lapsing on exposure to weather, the growing margin remaining tomen- tose; obscurely marked with structural zones, especially near the margin, where there may appear an interrupted blackish zone. Flesh about 1 mm. thick, color of surface, fibrous and rather spongy. Hy- menium thin, about 55-65[j, thick, white when young, then approach- ing the cap color, becoming dark brown when bruised in the growing state; texture much more firm and brittle than the flesh; furnished with thick, refractive, embedded gleocystidia; cystidia also present, encrusted, blunt or pointed, 3.5-4jx thick, projecting about 9-22[jl. Spores oval, smooth, 2.3-2.5 x 3.5-4[j,. Burt makes an error in not crediting this from North Carolina, putting Salem, under South Carolina. 1921] The Thelephoraceae of North Carolina 185 689. On dead sweetgum, December 3, 1912. Photo. Blowing Rock. On rotting wood. Atkinson. Common, on logs and limbs. Curtis. THELEPHORA Plants tough, leathery, fan-shaped, or funnel-shaped, or much branched; hymenium smooth or somewhat wrinkled, covering only the interior (or outer) surface in most species, but clothing all but the stalk in a few branched forms; basidia simple; spores colored, rough or spiny. A few branched kinds as T. palmata and T. antho- cephala have the form of Clavarias but are distinguished from these by the tough, leathery texture and very dark spores. Lachnocladium forms of Clavaria approach these in texture, but have light spores. (See Burt, Ann. Mo. Bot. Gard. 1: 199. 1914, for a full treatment of the genus in North America.) Key to the North Carolina Species * Plants stalked and upright, growing on the ground Branched like a tree or shrub and rather stout, 3-6.5 cm. high. Odor very strong and foetid T. pahnata (1) Odor none T. multipartita (2) Branched like a tree or shrub, slender, 1.5-2.7 cm. high T. caespitulans* Simple, small, flattened and broadened upward T. regularis (4) Simple, or lobed, expanded above into more or less com- plete shallow, thin and pliable cups. In pine or cedar woods or open fields. Cap not zoned, fibrous-squamulose, margin fimbriate. . .T. terrestris (5) Cap zoned, inherently squamulose, margin even at ma- turity T. intyhacea (6) Cap zoned, silky fibrous, margin fimbriate T. griseozonata (7) Expanding above into a complicated mass of concen- tric plates, lobes or tubercles, thick and firm T. vialis (3) Plants laterally sessile, bracketed, growing on wood or up from the ground onto bases of stems. Sometimes cen- trally stalked and expanded into a cup above when grow- ing upright. * Thelephora caespitulans has not been found in North Carolina, but should be looked for as it occurs both north and south of us. We take the following from Burt (1. c. 1 : 204. 1914): "Fructification erect, coriaceous, dusky drab to oUve-brown below, paler above, very much branched, forming clusters 2}4 cm. high by 2}/^ cm. broad; pileus with numerous divisions joined together into a solid base but assurgent above and pressed together closely compressed, subcanaliculate, frequently obtuse and whitish at the apex; hymenium amplii- genous: spores umbrinous imder the microscope, sparingly tuberculate, 7-8 X 5-6M. On the grovmd in mixed woods, Vermont to South Carolina, and in dense coniferous woods, Wash- ington. September. Rare. Tliis species is related to T. palmata but is more olivaceous, and it is probably inodorous, — at least no odor has been noted." 186 Journal of the Mitchell Society [February Blackish when fresh, with white margin when dry, brownish above with a gray-tlrab hymenium T. cuticularis (8) - Dull cinnamon or chestnut, margin paler when growing, soft and spongy T. albido-brunnca (9) Yellowish, hard when dry T. lutosa (10) Plants incrusting and ascending small plants or twigs from the ground T. fimbriata (11) 1. Thelephora palmata (Scop.) Fr. This species, which is sharply marked by its upright branched habit, dark color and very foetid odor, has not yet been found in Chapel Hill, and in the following description of the fresh plant I have made use of notes by Miss M. McKenney, of Olympia, Wash- ington. The species is northern in its range and descends to our state only in the mountains, so far as known with certainty. Cm-tis reports it as common in woods in this state, but he may have had some other plant in mind. Gregarious or tufted, 3-6 cm. high, 2.5-4 cm. broad, trunk thin, flattened, black. Branches numerous, flattened, black; these branch again into slender branchlets which are round, flexible, tough, simple or occasionally flattened, divided, narrowing at the tip, which is white or gray. Odor most disagreeable, something like decayed cabbage combined with iodoform. Spores (of a plant from Olym- pia, Wash.) blackish brown, irregularly warted or spiny, 7.4-9.3 x 8-11. l[x. In the dried state the plants are deep brown on the surface, the central flesh remaining black. They are rather brittle with nearly as much the appearance of a Clavaria as of a Thelephora, entirely smooth with a surface of velvet-like appearance all over. Odor retained, taste similar, bad, a good deal like that of Hijgrophorus Peckii. Burt gives the color of fresh plants as fuscous purple. The plant is found under conifers or in grassy fields. Asheville. Beardslee. Common on earth in woods. Curtis. 2. Thelephora multipartita (Schw.) Fr.* Plates 24 and 35 Plants about 2.5-3.5 cm. high, and 1.5-2.5 cm. broad above, distinctly stalked and dividing above into rather narrow, flattened * Thelephora anthoccphala (Bull.) Fr. is reported from North Carolina by Biirt (from Beardslee) and by Curtis. We have not found a plajit that we can separate from T. multi- partita as this, and as we cannot work out any difference from descriptions that will make a clear distinction between the two species we refrain from copying a description (see Burt, . c, p., 203). PLATE 24 THELEPHORA MULTIPARTITA. No. 346§. 1921] The Thelephoraceae of North Carolina 187 and channelled branches with white or whitish, finely tomentose, sterile tips; hymenium deep brown when fresh and moist, about warm sepia of Ridgway, in drying becoming lighter, between fawn and wood-brown of Ridgway. Stem rough, irregular, usually more or less flattened, surface felt-like. Texture tough, pliable; tasteless and odorless. Spores (of No. 2590) deep smoky sepia, a large mucro, irregu- larly set with blunt spines, 5.5-7.4 x 7.4-9. 3[jl. The tomentose tips, densely spinulose spores and particularly the lack of odor separate this from T. palmata. Dr. Burt has seen our plants and refers them as above. The stem is said to be villose, but this is not the case in our plants and ours are at times much larger than the maximum dimensions given by Burt. 2590. On earth, upland rocky woods (mixed oak and pine), Battle's Park, July 5, 1917. Photo. 2641. Low, damp woods by Meeting of the Waters branch, July 11, 1917. 2695. Low, damp woods by Creek at Upper Laurel Hill, July 17, 1917. 3468. In rich humus near base of oak near Meeting of the Waters, August 16, 1919. Photo. Deep brown with tint of purple; tips Hghter. On dry- ing colors become lighter. Spores deep smoky brown, irregularly warted or with blunt spines, 4.5-7 X 6. 5-8. 5m. 4610. Damp, sandy soil below Meeting of Waters, July 31, 1920. Plants 2-3 cm. high. North Carolina. Schweinitz. 3. Thelephora vialis Schw. T. tephroleuca B. & C. Plate 26 Plant about 3-5 cm. high, and about 3-6 cm. broad, expanding and branching upward from a contracted base. The branchlets are broad and flat and fuse at any point, usually so consolidated as to form one complicated mass with the upper surface deeply lobed and nodulated. Flesh firm, coriaceous, very hard on drying and then giving off a distinct, rather sharp, aromatic odor that is hardly dis- agreeable. Hymenium inferior, rugose or smoothish, pale yellowish when young, becoming brown. Spores said by Burt to be olive buff under the microscope, bluntly angular, 4.5-5 X 4.5-7tJL. Burt notices a "disagreeable" odor in drying; others do not men- tion an odor. We have found the plant to be rare here. When 188 Journal of the Mitchell Society [February Curtis speaks of it as common he probably included the very common Tremellodendroyi candidum. 1059. On ground in woods near campus, fall of 1913. Asheville. Beardslee. North Carolina. Atkinson. North Carolina. Schweinitz. Common, woods and roadsides. Curtis. 4. Thelephora regularis Schw. Plate 25 Small plants growing on damp mossy earth; at times spathulate in form, flat or the margins rolled back so as to be half infundibuli- form, again infundibuliform with the margin divided and multiple (as in No. 4435), height about 2-3 cm., the base narrowed gradually into a cylindrical stalk about 1-2 mm. thick. Flattened portion about 5-15 mm. wide. Dorsal surface nearly smooth or roughish tomentose with Hght channels, and sometimes tubercles, a buffy flesh color; spore-bearing surface a dark fleshy gray or purplish fawn, with a glaucous bloom. Flesh tough, elastic, about color of the dorsal surface, with a bitterish harsh taste. In drying the plants become grayish brown, losing their flesh tints. Young parts of both hymenium and dorsal surface turn a dark wine brown when rubbed. Spores when fully mature, angular, about honey color under the microscope, subspherical, smooth, 5-6[jl in diameter. The spores are slow to take their color and to become rough, still appearing white and smooth until nearly full grown. Basidia club-shaped, four-spored, sterigmata about 4[j, long; no cystidia. According to descriptions the plants may assume a regular in- fundibuliform shape like a perfect cup, and Burt thinks (1. c, p. 206) that T. multipartita, which is reported by Schweinitz from this state, is only a branched form of this species. 1597. In damp mossy earth by branch southwest of graded school, July 10, 1915. 1622. Same spot as No. 1597, July 21, 1915. Photo. 4435. Damp, sandy soil by Battle's Branch, July 17, 1920. Salem. Schweinitz. North Carolina. Atkinson. PLATE 25 THELEPHORA REGULARIS. No. 1622. PLATE 26 THELEPHORA VIALIS. No. 1059 [above]. THELEPHORA TERRESTRIS. No. 3840 [below]. 1921] The Thelephoraceae of North Carolina 189 5. Thelephora terrestris Ehrh. T. laciniata Pers. Plate 26 Caps scattered to densely imbricated, in part incrusting, more or less fused, bracketed and broadly attached by the side, projecting about 1-2 cm., upper surface deep brown, fibrous-squamulose and ridged all over, not zonate; hymenium brown, paler on margin, un- even; margin thin, fimbriate. Flesh thin, very soft, phable and spongy-fibrous, color of surface, absorbing water immediately. Spores not to be obtained from our plants when found. Burt gives them as pale fuscous, irregular, angular, sometimes slightly tuberculate, 6-9 X 6^. Recognized by the squamulose cap, dark color, very soft and spongy, bibulous flesh and shelving growth on coniferous substrata, upon which it climbs from the ground. According to Burt the spe- cies also grows in sandy fields. For further interesting observations by Burt see Ann. Mo. Bot. Gard. 1: 219. 1914. 3840. Running up the base of a cedar from the ground, south of athletic field. December 7, 1919. Photo. Asheville. Beardslee. Salem. Schweinitz. Common on earth and trunks. Curtis. 6. Thelephora intybacea (Pers.) Fr. Plate 35 Plant 5.5 cm. high, 4.5 cm. broad, compound from a solid amor- phous base, the flabelliform, petaloid or infundibuliform blades aris- ing on more or less distinct stalks and gradually expanding upwards; margins thin, expanded, more or less lobed and cut, but not fimbri- ated; dorsal (interior) surface inherently fibrous and ridged but not squamulose, dark brown, about Prout's brown to bister of Ridgway; when dry the margins black; hymenial (outer) surface a lighter gray- brown (buffy-drab) , the younger parts paler. Texture when dry rigid and hard above, very firmly spongy below; when wet pliable and elastic and quite bibulous; odor none when dry, but when wet it has a strong rank smell, something like freshly cut black oak. When wet the hymenium is much darker and approaches the dorsal surface in color. 190 Journal of the Mitchell Society [February Spores (of No. 4672) irregularly angled, strongly papillate-warted, 5-7 X 6-7.5[x. Distinguished from T. terrestris by the absence of free squamules and the non-fimbriate margin. Both are found on coniferous sub- strata. In our only specimen there has been proliferation on the dorsal surface which has obscured the color by adding a spongy whitish layer over much of the middle and lower region. 4672. Mixed woods by Battle's Branch, among pine needles and a few oak leaves, October 9, 1920. Asheville. Beardslee. 7. Thelephora griseozonata Cooke Plates 27 and 35 Plants up to 5.5 cm. wide, usually about 2.5-3 cm., stalked and upright, the thin, pliable, tough cap spreading upward like an irregu- lar dish with deep lobes or only shallow cuts, very fibrous and radi- ately ridged, the margin fimbriated in all cases; color deep brownish- purple all over, the upper side with rather conspicuous zones of dif- ferent tints. Hymenium rugose with low veins, disappearing grad- ually into the stalk Stalk 3-7 mm. thick and 1-1.8 cm. long, tough, color of cap. Spores purplish brown, irregularly lobed and warted, oblong, about 5.5 X 7.5^. The plants are gregarious but usually single or lightly clustered. They occur in colonies under pines. 975. In pines, hillside pasture, west side of Glen Burnie Farm, November 11, 1913. Photo and drawings. It also occurs in a similar situation on the east side of Glen Burnie Farm. 2426. Under young pine on Three Pine Hill, Glen Burnie Farm, July 26, 19] 6. Photo. 8. Thelephora cuticularis Berk. Plate 35 Plants shelving, laterally sessile by a more or less resupinate base, often confluent laterally, projecting about 2-4 cm. Dorsal surface radially wrinkled, inherently fibrous and felted, the margin felted pubescent when quite fresh; in the wet, growing state nearly jet black, the wrinkled margin pure white; hymenium drab with a tint of purple when dry, nearly black when wet. Flesh rather thin, <5 < O o w o O W K H 1931] The Thelephoraceae of North Carolina 191 about 1-1.5 mm. thick, pliable, easily water-soaked, color of the surface both when wet and when dry. In our plants there was no noticeable odor in the fresh state, but the dried plants have a faint, not unpleasant drug-Uke odor. The species is said by Berkeley to have a foetid odor, and Burt noticed such an odor in the dried state. Spores (of No. 3432) smoky brown, subspherical, flattened on one side, covered with sharp spines, 7.4-9 x 7.4-1 Ijjl. The black color of the plants (both dorsal surface and hymenium) in the damp growing state is not mentioned in the descriptions. It is the most conspicuous field character. If dropped in water after drying the dorsal surface and context absorb water and change color instantly as in T. terrestris and T. alhido-hrunnea, but unlike those the hymenium absorbs water much more slowly and becomes black only after several minutes. This, with the blacker color (when wet), furnishes an easy mark of distinction. 3432. On bark of oak tree, Battle's Park, and some from below Meeting of the Waters, August 1.5, 1919. 9. Thelephora albido-brunnea Schw. Plates 28 and 35 Caps tough and elastic, horizontal and irregularly bracketed or sometimes centrally stipitate from an amorphous, resupinate, often spore-bearing base, extensively fused together, the individual caps not often more than 3.5 cm. wide, or extending more than 1.8 cm.; often encircling and climbing up sticks or shrubs or small saplings for several inches and in such case thicker and more amorphous; surface fibrous-spongy, tomentose when young, distinctly or obscurely zonate, dull cinnamon or buffy cinnamon, or when young pale brown to whitish, becoming paler when washed out in age by the weather, margin blunt, white in growing stage, later concolorous. Flesh about 1-2.5 mm. thick in the distinct caps, thicker in the amorphous masses; felty and soft, the fibers extensively furnished with clamp connections at the joints, color of surface or a darker rust color. Hymenium when fresh brownish drab to wood brown, fleshy-looking, when old and dry very hght fleshy brown, smooth, no setae, easily wearing off and exposing the rust-colored flesh below. Spores (print of No. 4409) smoky brown, irregularly angled, echinulate, 7-10 x 7.4-1 1[jl. 192 Journal of the Mitchell Society [February When dropped in water after drying the entire plant, including the hymenium, becomes water-soaked immediatel5\ 1328. On soil and sticks, just above path by Battle's Branch, east of Dr. Battle's, October 9, 1914. Spores rusty, tuberculate-spiny, subspberical, about 7.6m in diameter. 4409. Around bases of young living trees and shrubs, July 14, 1920. Photo. 4467. Base of tree near Meeting of the Waters, July 27, 1920. Spores dark smoky purple, spiny, 6-7.5 X 7.5-10m- 4470. Around a rotten twig on damp soil, July 30, 1920. 10. Thelephora lutosa Schw. This is known only from the type collection which is from Salem, N. C. Bm-t describes the plant as follows (Ann. Mo. Bot. Gard. 1 : 216): "Pilei cespitose, densely imbricated, at first somewhat fleshy but at length hard, undulate-plicate, yellowish, almost subtomen- tose with pulverulence, somewhat horizontally attenuated behind, margin sublobate, at length inflexed; pileus less than 2 mm. thick, with hyphae 3[jl in diameter; hymenium becoming yellowish, even; spores olive-buff under the microscope, angular, 5-6 X 33/2~4[jl. ''Cluster about 13^2 cm. high and broad. "On the ground in roads and in woods. North Carolina. "The type is distinct from T. albido-bnmnea, having thinner pileus, finer hyphae, and smaller and paler spores. The pilei were crowded together into a small buff-colored cluster about 13^ cm, high and broad, somewhat as in Tremellodendron pallidum (Schw.); I failed to find stems at their bases." 11. Thelephora fimbriata Schw. The only record from this state seems the original one by Schwein- itz (as Merisma). We have examined two collections of this from Andros, Bahamas (determined by Burt), and find that there are dense clusters of branches, simple to sparingly branched which reach a length of 1.3 cm. They are a buffy ochraceous when dry and are densely felted with intricately branched hairs. As we have not found the plant in the fresh state we take the following from Burt (Ann. Mo. Bot. Gard. 1: 222. 1914): "Fructification coriaceous-soft, incrusting and ascending small plants (mosses, etc.) here and there emitting fascicles of branches united below, subterete, acuminate or fimbriately incised, at first PLATE 28 THELEPHORA ALBIDO-BRUNNEA. No. 4470 [top left]; No. 4407 [top right]; No. 4409 [below. 1921] The Thelephoraceae of North Carolina 193 pale or whitish, soon ferruginous brown, drying Rood's brown; hy- menium even, pruinose-pubescent; spores umbrinous, tuberculate, 7-11 X 6-9tx. "Incrusting and ascending upward 1-3 cm.; free branches 5-10 mm. long, 1 mm. thick, sweep of fascicle about 5-10 mm. "In moist places. New York to South Carohna, and west to Illinois. July and August. "The type is an incrusting specimen, covering as its main axis a small twig in one specimen and a moss in the other, and sending out a few lateral branches which are flattened towards the free ends and 'subfimbriate; main trunk is cyhndric, latericius (of 'Chromo- taxia'), ends of branches paler; spores umbrinous under the micro- scope, tuberculate, 7-8 X 6[jl. Schweinitz described the species as becoming hard and cartilaginous, but this is an error probably due to the foreign matter surrounded by the main trunk. Several other specimens are present in his herbarium under various names." Salem. Schweinitz. SPARASSIS Tough and elastic but fleshy, repeatedly branched into a semi- globose mass of flat, contorted, anastomosing branches, the hy- menium covering only the outer (morphologically under) surfaces, except at times on the innermost vertical branches (see Cotton, Trans. Brit. Myc. Soc. 5: 333. 1911). This fact requires the re- moval of Sparassis from the Clavariaceae, where it has usually been referred. We have found only one species in Chapel Hill, which we refer to S. Herhstii Pk., without conviction that it is different from S. spathulata Schw. Spm-assis crispa is found in our mountains. All species are edible, and are credited with being dehcious. For parasitism of Sparassis see Hedwigia 54: 328. 1914; and Journ. Royal Myc. Soc. for 1914, page 386. Key to the Species ( S. Herhstii (1) Branches thick, blunt, not crisped j ^ spathulata (2) Branches thin, much crisped S. crispa (3) 194 Journal of the Mitchell Society February 1. Sparassis Herbstii Pk. Plates 29 and 35 A large and very pretty plant of a complicated growth, that occurs on wood that is usually under or at the surface of the ground. It is composed of many upright and spreading, flat, rather thick, anas- tomosing branches with blunt ends that spring from a single large fleshy base. The entire plant is approximately globose or flattened- globose and is of variable size, in No. 1363 being about 14 cm. high and 15 cm. broad. The apices of the branches are whitish and tomen- tose, the lower parts cream colored, water-soaked, and smooth. The texture of the whole is very tough and elastic. The plate-like branches bear spores only on the outer surface, and in fresh specimens the texture of the two surfaces can be seen to be different. Spores (of No. 1363) white, nearly spherical to short-eUiptic, smooth, one large oil drop, 3.4-4.2 x 4.6-6.8^1. This is possibly not different from the next. 524. In pine woods northwest of Mr. Weaver's house across railroad, October 6, 1912. Photo. 787. Woods south of athletic field, September 17, 1913. 1363. Growing from between the bark at foot of a pine stump in the new road to Piney Prospect, October 16, 1914. 2. Sparassis spathulata (Schw.) Fr. Stereum carolinense Cooke and Rav. This is possibly not different from *S. Herbstii Pk. but I give below the original description (translation) : "Erect, coriaceous, paUid brown, concrescent from upright blades, with spathulate branches wavy at the apex and rounded zones. Rare in grassy places, also sent from Georgia; reaching six inches in height, growing in large groups, with concentric horizontal zones. Of doubtful genus and said to be uncertain as to whether it is more nearly related to Clavaria crispa or Spathularia." To this scanty diagnosis I add the original description of Stereum carolinense Cooke and Ravenel (Journ. Myc. 1: 130. 1885), which Cotton has shown to be almost certainly Sparassis spathulata. (Trans. Brit. Myc. Soc. 5: 336. 1911.) "Pileus multiplex, infundibuliform, deeply incised, forming lobes variable in size, all confluent at the base in a common stem. Whole plant six inches high, 4-5 inches broad, ochraceous, with faint zones PLATE 29 SPARASSIS HERBSTII, No. 524. Slightly reduced. 1921] The Thelephoraceae of North Carolina 195 of darker color, margin of lobes entire, surface smooth. Hymenium even, ochraceous-white; stem minutely velvety." Wilmington, N. C. (As Slereum caroliniense Cke. and Rav.) Dr. Thomas F. Wood. Low and middle districts on earth. Curtis. 3. Sparassis crispa (Wulf.) Fr. This fine species is rare in North Carolina. It has not been found in Chapel Hill, but I have seen it at Kanuga, and Beardslee has it from Asheville. It is much more crisped and irregular than *S. Herhstii, with thinner and more intricate branches that do not form the rather obvious labyrinths that are characteristic of the latter species. Its diameter is usually about 10-20 cm., but it has been reported larger. The color is a soaked, translucent, yellowish- white, becoming brownish in age. Like S. Herhstii, it also grows from the wood of conifers that is on or under the ground. Edible and very good. Asheville. Beardslee. Kanuga. Coker. Upper district, on earth. Curtis. Chapel Hill, N. C. Explanation of Plates PLATE 30 Cyphella muscigena. No. 393 L Fig. L Cyphella fascicvlaia. No. 400L Fig. 2. Cyphella cupulaeformis. No. 4019. Fig. 3. Solenia poriaeformis. No. 4686. Figs. 4-6. Aleurodiscus Oakesii. No. 3937. Figs. 7-1 L Aleurodiscus candidus. No. 3827. Figs. 12-14. Aleurodiscus candidus var. sphaerosporus. No. 3902. Figs. 15-17. Figs. 1, 2, 5, 11, 13, 15, X 1440; fig. 6 X 108; others X720. PLATE 31 Aleurodiscus riivosus. No. 3897. Fig. 1; No. 3920. Figs. 2 and 3. Aleurodiscus botryosus. No. 4710. Figs. 4-6 (fig. 5, paraphysis and proteid body). Aleurodiscus macrodens. No. 4734. Figs. 7-9. Coniophora arida. No. 4219. Figs. 10 and 11. Peniophora gigantea. No. 4306. Fig. 12. Peniophora violaceo-lividum. No. 3914. Fig. 13. Peniophora albomarginala. No. 3849. Figs. 14 and 15. Figs. 1, 4, 11, 14, X1440; others X720. 196 Journal of the Mitchell Society [February PLATE 32 Peniophora cinerea. No. 4299. Fig. 1 ; No. 4045. Fig. 2. Peniophora longispora. No. 4250. Fig. 3. Peniophora mutata. No. 3993. Fig. 4. Peniophora filamentosa. No. 4264. Fig. 5; No. 4607. Fig. 6 (in fig. 5 crystals dissolved off by KOH). Hypochnus fuscus. No. 4267. Figs. 7-9. Hymenochaete corrugata. No. 4076. Fig. 10. ,» Hymenochaete Curtisii. No. 3830. Fig. 11; No. 3875. Fig. 12. Figs. 1, 8, 1), X1440; others X720. PLATE 33 Corticium caeruleimi. No. 4018. Fig. 1. Corticium lilacino-fuscuni. No. 4071. Fig. 2. (This fails to show paraphvses well.) Corticium roseum. No. 4703. Figs. 3 and 4 (basidium and contorted thread of hymenium); No. 3981. Fig. 5. Corticium Viticola. No. 4693. Fig. 6. Corticium arachnoideum. No. 4235a. Figs. 7 and 8. Corticium vagum. No. 4259. Fig. 9; No. 4230. Fig. 10. Figs. 5, 6, 8, 9, X1440; others X720. PLATE 34 Corticium scutellare. No. 4223. Fig. 1; No. 4696. Fig. 2. Asterostroma cervicolor. No. 4507. Figs. *¥— *^ (Fig. "W-, fragmentary hyphae of lower region). 3— <» <» Figs. 2,'9r8' X 1440; l,\ X 720; ^'X 10? ; others X 4\7. f i PLATE 35 Stereum gaumpatum. No. 3821. Fig. 1. Stereum sanguinolentum. No. 3967. Fig. 2. Stereum subpileatum. No. 3955. Fig. 3. Stereum lobatum. No. 3816. Fig. 4. Stereum rameale. No. 3863. Fig. 5. Form on cedar. No. 4318. Fig. 6. Stereum sericeum. No. 3962. Fig. 7. Stereum ochraceoflavum. No. 4033. Fig. 8. Stereum frustulosum. No. 3814. Figs. 9 and 10. Thelephora multipartita. No. 3468. Fig. 11. Thelephora intybacea. No. 4672. Fig. 12. Thelephora griseo-zonata. No. 975. Figs. 13-15. Thelephora cuticularis. No. 3432. Fig- 16. Thelephora albido-brunnea. No. 4467. Fig. 17. Sparassis Herbstii. No. 1363. Fig. 18. Figs. 1-8, 10-12, 16-18, X1440; others X720. PLATE 31 PLATE 32 PLATE 33 PI. ATE 34 PLATE 35 0) U 15 ov (O, f^ ■ r /' t 16 CONTENTS OF RECENT NUMBERS Volume 35, Double Number 1 and 2 Proceedings of the Eighteenth Meeting of the North Carolina Academy of Science 1 Notes on the Occurrence of Tintinnus Serratus in Chesa- peake Bay. Bert Cunningham 12 On Some Generic Distinctions in Sponges. H. V. Wilson . . 15 A Portable Printing Press for the Ecologist. Z. P. Metcalf 20 Craterellus, Cantharellus, and Related Genera of Gill Fungi. W.C.Coker 24 JuGLONE. Alvin S. Wheeler 49 Our Rats, Mice, and Shrews. C. S. Brimley 55 Notes on the Flora of Church's Island, North Carolina. W. L. McAtee 61 The Distribution of Rhododendron Catawbiense, with Remarks on a New Form. W. C. Coker 76 Volume 35, Double Number 3 and 4 Chlorination by Mixed Carbon Monoxide and Chlorine. Francis P. V enable and D. H. Jackson 87 A Rapid Volumetric Method for Determination of Arsenic IN Arsenates. James M. Bell 90 The Land of Ferns. John K. S^nall 92 The Regional Geography of South Carolina Illustrated BY Census Statistics. Roland M. Harper 105 Notes on the Lower Basidiomycetes of North Carolina. W. C. Coker 113 Volume 36, Double Number 1 and 2 Proceedings of the Elisha Mitchell Scientific Society, . December, 1916, to March, 1920 1 Proceedings of the North Carolina Academy of Science , . 7 The Theory of Relativity. A. H. Patterson 19 A New Method for Laying Out Curves by Deflection FROM THE p. I. T. F. Hickerson 42 A Remarkable Form of Skeletal Element in the Lithistid Sponges (a Case of Analogical Resemblance). H. V. Wilson 54 The Turtles of North Carolina. C. S. Brimley 62 A Little-Known Vetch Disease. Frederick A. Wolf 72 Notes on the Mosquito Fauna of North Carolina. Frank- lin Sherman 86 An Interesting Fertilizer Problem. H. B. Arhuckle 94 Azalea Atlantica Ashe and Its Variety luteo-alba n. var. W. C. Coker 97 A New Species of Achlya. W. C. Coker and /. N. Couch 100 JOURNAL OF THE Elisha Mitchell Scientific Society VOLUME XXXVII 1921-1922 ISSUED QUARTERLY Published for the Society by the University of North Carolina t CONTENTS Proceedings of the Elisha Mitchell Scientific Society, February, 1921, to May, 1921 1 Proceedings of the Twentieth Annual Meeting of the North Carolina Academy of Science 6 John Francis Lanneau, 1836-1921 17 The Age of Insects. Z. P. Metcalf 19 The Genus Raspailia and the Independent Variability of Diagnostic Features. H. Y. Wilson 54 An Interesting Maximal Case. Archibald Henderson and H. G. Baity 61 Key to the Butterflies of North Carolina. C. S. Brimley . . 73 A Theorem on Double Points in Involution. J. W. Lasley, Jr. 80 The Collybias of North Carolina. W. S. Coker and H. C. Beardslee 83 Abstracts and Reviews 108 Isotopes. Francis P. V enable 115 Some Considerations in Defense of the General Biology , Course. J. P. Givler 123 Notes on the Oecology and Life-History of the Texas Horned Lizard, Phrynosoma Cornutum. J. P. Givler .... 130 A Magnetite-Marble Ore at Lansing, N. C. W. 8. Bayley .... 138 A Botanical Bonanza in Tuscaloosa County, Alabama. Roland M. Harper 153 Fishes in Relation to Mosquito Control. Samuel F. Hildehrand 161 Notes on the Morphology and Systematic Relationship OF Sclerotium Rolfsii Sacc. B. B. Higgins 167 An Interesting Anomaly in the Pulmonary Veins of Man. W. C. George 173 The Eastern Shrubby Species of Robinia. W. W. Ashe 175 A New Oak from the Gulf States. W. D. Sterrett 178 A New Genus of Water Mold Related to Blastocladia. W. C. Coker and F. A. Grant 180 Forest Types of the Appalachians and White Mountains. W. W. Ashe 183 Index to Volumes 32-37 200 DOUBLE NUMBER VOL. XXXVII DECEMBER, 1921 Nos. I & 2 JOURNAL OF THE Elisha Mitchell Scientific Society CONTENTS Proceedings of the Elisha Mitchell Scientific Society, j^ February, 1921, to May, 1921 i Proceedings of the Twentieth Annual Meeting of the North Carolina Academy of Science 6 John Francis Lanneau, 1836-1921 ..17 The Age of Insects. Z. P. Metcalf 19 The Genus Raspailia and the Independent Variability of Diagnostic Features, H. V. Wilson 54 An Interesting Maximal Case. Archibald Henderson and H. G. Baity 61 Key to the Butterflies of North Carolina. C. S. Brimley. . . 73 A Theorem on Double Points in Involution. /. W. Lasley, Jr.. 80 The C0LLYBLA.S of North Carolina. W. C. Coker and H. C. Beardslee 83 Abstracts and Reviews 108 ISSUED QUARTEBLT CHAPEL HILL, N. C, U. S. A. ENTERED AT THE POST OFFICE AS SECOND-CLASS MATTER The Elisha Mitchell Scientific Society W. deB. MacNIDER, President. W. F. PROUTY, Vice-President. J. M. BELL, H. R. TOTTEN, Permanent Secretary. Recording Secretary. Editors of the Journal: W. C. COKER, Chairman. J. M. BELL. COLLIER COBB Journal op the Elisha Mitchell Scientific Society — Quarterly. Price $3.00 per year; double numbers, $1.50 Numbers for sale are listed iuside the back cover. Direct all correspondence to the Permanent Sec- retary, at the University of North CaroUna, Chapel Hill, N. C. In addition to original papers on scientific subjects this Journal pub- lishes the Proceedings of the Elisha Mitchell Scientific Society, and the Proceedings of the North Carolina Academy of Science, as well as abstracts of papers on scientific subjects published elsewhere by members of the Fac- ulty of the University of North Carolina. Published for the Society by the University of North Carolina PLATE 1 1 COLLYBIA LILAClNAn. sp. No. 3290 2 (X)LLYBIA CIRRATA. No. 3743 3. COLLYBIA PLATYPHYLLA. No. 1263 JOURNAL Elisha Mitchell Scientific Society Volume XXXVII DECEMBER Nos. I and 2 PROCEEDINGS OF THE ELISHA MITCHELL SCIENTIFIC SOCIETY, FEBRUARY, 1921, TO MAY, 1921 246th Meeting— February 8, 1921 Dr. Edward J. Wood (Class of 1899), of Wilmington, N. Q.~Our Debt in Medicine to the British. The speaker mentioned briefly a few of the outstanding contribu- tions to the making of modern medicine by the British. The pioneer worker was William Harvey who described the circulation of the blood and must be accredited with the discovery. Special reference was made to that little group of nineteenth century physicians in London who, at Guy's Hospital, made such a remarkable contribu- tion within a few years. There was Addison who first described Ad- dison's disease. Bright who first described Bright 's disease, Hodgkin who first described Hodgkin 's disease and finally Sir Ashley Cooper, a great surgeon and a pioneer in medical education. The real burden of the address was the contribution in parasitol- ogy. The remarkable achievements of Sir Patrick Manson were mentioned briefly, the genius of Louis W. Sambon applying his great knowledge of medical zoology, the discovery of the mosquito in its role in malaria transmission by Sir Ronald Ross, the work of Sir David Bruse and others in determining the relation of the trypano- some to sleeping sickness of Africa and the relation of the tse-tse fly to its transmission. The work of Sir William Leishman in the dis- covery (with division of honor to Donovan) of the protozoal cause of dum-dum fever of India. The need of a medical zoological survey in North Carolina was mentioned. It was hinted that schistosomiasis had been recently found in the state and at least one case of kala-azar. The educational need along these lines was also emphasized. [11 2 Journal of the Mitchell Society [December 247th Meeting— March 8, 1921 W. C. George. — Comparative Anatomy of the Brain. The principal morphological sulxlivisions and connections of the human brain were described and their probable phylogeny outlined. The relation of the environmental conditions and habits of life of animals to the degree of development of special parts of the brain was indicated. Dissections of brains of an elasmobranch fish, a frog, reptile, bird, rat, mole, cat and man were exhibited to show homolo- gous parts of the brain and the degree of development under different conditions of life. Otto Stuhlman, Jr. — So77ie Unsolved Problems of Modern Physics. No science has gone through a more stormy period of develop- ment than physics during the last decade. Our most cherished theories have undergone most violent upheavals, the result of which no one at this time can predict with certainty. These discoveries have forced us to adopt new and contradictory explanations, w^hich in general may be divided into three groups: (a) X-rays and the emissions from radio-active substances ; (5) The theory of radiation ; (c) The so-called theory of relativity. Of these the "Theory of Radiation" was discussed and some of the outstanding problems that require solution were explained in detail. Amongst those mentioned was Wien's Displacement Law and the contributions made by Planck. The classical theory of specific heat and entropy and its quantum modifications were discussed. The quantum theory as applied to the emission of electrons from bodies was mentioned and some of the outstanding problems were discussed in detail. The unsolved problems in the photo-electic field were next enumerated and their possible bearing on the structure of matter was sketched. Series spectra and the numerous problems confron- ting the physicist in this field were finallj^ enumerated. The paper closed with a review of the Lewis-Langmuier theory of the structure and physical properties of nitrogen and carbon monoxide. 248th Meeting— April 12, 1921 Thorndike Saville — The Water Power Situation in North Carolina. This paper presents the results of a statistical study of the devel- 19£l] Proceedings of Elisha Mitchell Scientific Society 3 oped hydro-electric power in North Carolina. It is shown that there is at present a total installed capacity of about 356,000 H. P. in plants producing hydro-electric power. Of this, 80,000 H. P. or 22 per cent is transmitted for use outside the state; 113,000 H. P. or 32 per cent is used at Badin in the local reduction of aluminum; while only 164,- 000 H. P. or 46 per cent is available for general industrial and public use. Of the latter 98,500 H. P. or 28 per cent of the total (60 per cent of the 164,000 generally available) is developed by two large public service corporations. The total output of electrical energy by public service plants has increased 25 per cent from 1919 to 1920, and over 6000 per cent from 1907 to 1920. If the output increases at 12 per cent per year (one half the present annual rate) there will be a demand in 1925 for 1,434,000 kw. hr. and in 1930 for 2,528,000 kw. hr. To meet this de- mand, if the present proportion of output by water power is to be maintained (85 per cent) there will be needed additional develop- ment of 200,000 H. P. by water power in 1925 and of 624,000 H. P. by 1930. To develop this amount of water power will mean many new hydro-electric installations in the state, and the utilization of most of the economically available water power sites. It is estimated that about 1,500,000 H. P. is still undeveloped at sites in this state, but only a portion of this amount can be economically developed under present conditions. Fred F. Bahnson (Class of 1896), of Winston Salem, N. C.~The Science of Humidification, with Demonstration of a New Humidifier. Entirely too little attention has been paid to humidification in all manufacturing processes except those where the advantages are very plainly apparent, such as textiles. All materials of animal or vege- table origin and a number of mineral origin are affected by the humid- ity of the air in which they are stored or used, and this effect is pro- portional to the relative humidity or percentage of saturation, rather than the actual humidity or pounds of water per thousand cubic feet of space. Since the weight of a. cubic foot of saturated aqueous vapor just about doubles for each twenty degrees rise in temperature, it is ob- vious that even if the out-door humidity is sufficiently high, the in- door humidity will always be too low^ whenever artificial heat is used. This simply means that artificial means of supplying moisture must be used practically every day in the year, because even in summer 4 Journal of the Mitchell Society [December weather out-door humidity is apt to be below what it should be for satisfactory manufacture. "With exception of textile fibres, the curves for moisture content of various materials with reference to atmospheric conditions have not been determined. The various commercial methods of humidification were men- tioned and briefly described, and the Bahnson Humidifier was dem- onstrated under actual operating conditions. 249th Meeting— May 10, 1921 Archibald Henderson — The Lorentz Transformation in Einstein Relativity. Dr. Henderson attempted to give in the simplest possible mathe- matical terms the explanation of the Principle of Relativity (in the restricted sense), following the lines worked out by Einstein himself. After deriving the equations of the Lorentz transformations, Dr. Hen- derson gave their mathematical interpretation (1) The systems are en- tirely symmetrical; (2) A beam of light must have the same velocity, when viewed in the variables of either system; (3) The equations for low velocities reduce to the Newtonian equations; (4) A meter-stick perpendicular to the direction of motion remains constant. Analyz- ing these equations further, Dr. Henderson showed the interdepen- dence of time and space which they present, so that the phrase "points" in "space" is replaced by the expression "events" in "the world." The in variance function was interpreted as indicating a "rotation" in four-dimension Euclidian space with imaginary time- axis; or else, a "rotation" in four-dimension non-Euclidian space with real time-axis. It was pointed out that the Einstein theory of Relativity raises the deepest questions regarding space, time, gravi- tation, and the essential characteristics of the physical universe. W. C. CoKER — Effect of Length of Day on Growth and Reproduction of Plants. A review was given, illustrated by lantern slides, of the highly significant work of Garner and Allard on this subject. Mr. Allard was assistant in botany in this University sixteen years ago and went from here to the Department of Agriculture in Washington, where he is still working. In an extended series of experiments with growing plants the authors have shown that the length of day, that is the time 192l] Proceedings of Elisha Mitchell Scientific Society 5 of exposure to light, is by far the most important factor in initiating or retarding the production of flowers and fruit. For example, a certain variety of soy-beans when exposed to light for only seven hours a day blossomed on June 15th, while those exposed to full day- light did not bloom until September 4th. The majority of the plants experimented with showed similar hastening of flowering when ex- posed to short day, but several plants responded in the opposite man- ner and were much retarded in blooming by a short day. The au- thors believe that their work will have a considerable practical effect on agriculture, as it shows that the time of seeding for best results will depend on the lengths of day to which the crops will be exposed. They also believe that the natural distribution of plants on the earth is governed more or less directly by the seasonal length of day which obtains for the different latitudes from the equator to the poles. Election of Officers: President — ^W. DeB. MacNider. Vice-President — W. F. Prouty. Permanent Secretary — -J. M. Bell. Recording Secretary and Treasurer — H. II. Totten, Editorial Committee — W. C. Coker^ chairman; J. M. Bell, Collier Cobb. PROCEEDINGS OF THE TWENTIETH ANNUAL MEETING OF THE NORTH CAROLINA ACADEMY OF SCIENCE Held at Wake Forest College, Wake Forest, N. C. April 29-30, 1921 The Executive Committee met at 2.00 P. M. on April 29th in the Lecture Room of the Alumni Building with the following present: Z. P. Metcalf, President, and C. S. Brimley, Acting Secretary, other members, R. N. Wilson, F. A. Wolf, and A. H. Patterson, the latter acting for H. R. Totten, who was absent. President Metcalf stated that the Legislative Committee author- ized at the last meeting of the Academy to solicit funds from the legislature had not been appointed, owing to the financial stringency existing in the state at the time of the session of that body. He also stated that affiliation with the American Association had been com- pleted except for the official notice from the permanent secretary of that organization. The Executive Committee then passed resolutions recommending the following measures to the Academy for favorable action : 1. Increasing the annual dues to !H;2.00 per member. 2. .That the terms of the officers of the Academy should begin with the adjournment of the meeting at which they are elected, and should expire with the adjournment of the next regular annual meet- ing. 3. That the 10 per cent allo\\ed the Secretary-Treasurer should be only on the Academy dues collected by him, and not on the Ameri- can Association dues collected by him for that body in future. 4. Appointment of a Publicity Committee. 5. Appointment of a Committee on Preservation of our Natural Resources. The Executive Committee then received and accepted the offer of the University of North Carolina to hold the 1922 meeting at Chapel Hill. President Metcalf then announced that he had appointed Messrs. W. H. Pegram, R. N. Wilson, and A. H. Patterson to draw up suitable resolutions on the death of past-President of the Academy J. J. Wolfe, and that the same had been prepared and published in the Mitchell Journal, and that he had also appointed Messrs. W. L. Poteat and C. E. Brewer to do the same with regard to the death of past-President J. S. Lanneau. [6] 1921] Proceedings of the Academy of Science 7 Thirty-six new members were elected as follows:* W.J.Andrews, Miss Lucretia Baker, Miss E. E. Barrow, H. L. Blomquist, J. T. Barnes, Wayne Burch, Miss E. G. Campbell, L. A. Denson, R. T. Farrington, W. C. George, J. P. Givler, H. N. Gould, E. P. Jones, J. W. Lasley, Jr., W. Bruce Mabee, T. B. Mitchell, W. deB. MacNider, N. M. Paull, Charles PhilUps, T. E. Powell, Jr., R. H. Ruffner, E. E. Randolph, A. F. Roller, Miss Mildred Sherrill, S. C. Smith, Wilham E. Speas, Otto Stuhlman, Jr., R. W. Sullivan, C. C. Taylor, 0. J. Thies, Jr., H. M. Vann, R. B. Wilson, Mrs. B. W. Wells, Miss Lula G. Winston, Miss E. K. Wright, D. B. Wilson. The Executive Committee then adjourned. The Academy met at 2:30 P. M., when papers were read and dis- cussed. The following committees were then announced by Pres- ident Metcalf: Nominating — W. L. Poteat, A. S. Wheeler, and C. W. Edwards. Resolutions — Messrs. Bert Cunningham, J. B. Derieux and A. H. Patterson. Auditing — Messrs. R. N. Wilson, J. W. Nowell and W. C. Coker. The Academy then rose to accept the invitation of the Ladies' Community Club to take tea with them at the Golf Cabin. At 8.00 P. M. the Academy re-assembled in Wingate Memorial Hall to hear the Presidential Address of President Z. P. Metcalf on the "Age of Insects," which subject he handled in a highly instruc- tive and scientific manner. A very interesting paper on Judgments of Length, Mass, and Time by Dr. A. H. Patterson, of the University of North Carolina, followed, after which the Academy adjourned for the night. On Saturday morning, April 30th, the Academy held its business meeting at 9.00 A. M., President Metcalf in the chair. The Secretary then read the report and recommendations of the Executive Committee, all of which were adopted by the Academy. The Nominating Committee then reported the following names for officers of the Academy for the year beginning May 1, 192L President — James L. Lake, Professor of Physics, Wake Forest Col- lege. Vice-President — Joseph Hyde Pratt, State Geologist. Secretary-Treasurer — Bert Cunningham, Professor of Biology, Trinity College. Additional Members of the Executive Committee — Messrs. H. R. * For addresses see full list of Academy membership. 8 Journal of the Mitchell Society [December Totten, University of North Carolina; R. N. Wilson, Trinity College; F. A. Wolf, State College. The Secretary then on motion cast the vote of the Acadeni}^ for these gentlemen and they were declared elected. The Resolutions Committee reported the following resolutions which were adopted by a rising vote of the Academy: 1. That the North Carolina Academy of Science extend to the Fac- ulty and President of Wake Forest College most hearty thanks for and appreciation of their courtesy in tendering the use of the build- ings and equipment of the college for the meeting of the Academy, and in opening their homes to its members. This is the fourth meet- ing to be held here and our memory of Wake Forest, both of the town and of the college, has been one of consistent and generous hos- pitality. 2. That the North Carolina Academy of Science extend its thanks to the Ladies' Community Club of Wake Forest for the pleasant social courtesies extended to the members of the Academy at the Golf Club on yesterday afternoon and its hearty appreciation of the spirit of kindly hospitality which prompted the giving of the tea at the Club House. The Auditing Committee then reported that they had examined the accounts of Secretary R. W. Leiby and Acting Secretary C. S. Brimley and found them correct and in good condition. Reports follow: Report of R. W. Leiby, Secretary' Balance on hand April 29th, 1920 (audited) $196. 32 Receipts April 29 to Sept. 1, 1920 43. 00 Interest April 29, 1920, to April 1, 1921 5. 77 Total $245. 09 Disbursements Expenses Secretary at 1920 meeting .28 Telegram to E. W. Gudger 95 Stenographic Services (Miss Hinsdale) 5. 00 Collection on check .10 Elisha Mitchell Journal 75. 00 81.33 Balance on hand April 15, 1921 $1G3. 76 W21] Proceedings of the Academy of Science 9 Report of C. S. Brimley, Acting Secretary, March 25 to April 29, 1921 Receipts, dues and entrance fees $105. 00 Disbursements — Printing programs $17 . 00 Letterheads 6 . 00 500 stamped envelopes 12.31 Multigraphing 4 letters 3 . 00 10 per cent, on $105.00 10.50 48.81 Balance on hand April 29 $56. 19 Estimated Financial Condition of Academy — Leiby's balance $163. 76 Brimley's balance 56. 19 Unpaid dues and fees (est . ) 50 . 00 For programs from Chemists 5 . 00 Total Credit . . . $274.95 Expenses — Secretary's expenses at meeting 5 . 00 10 per cent, on $50.00 5. 00 Elisha Mitchell Journal 75 . 00 85.00 Estimated balance Jan. 1, 1922 .$189.95 President Metcalf then announced the appointment of the follow- ing committees: Publicity — Bert Cunningham, Chairman; A. H. Patterson, W. A. Withers. Preservation of Natural Resources. — Z. P. Metcalf, Chairman; J. S. Hohnes, W. C. Coker, J. P. Givler, H. L. Blomquist, B. W. Wells. On motion the Academy resolved to request the Mitchell Journal to publish the names of the officers and standing committees on the back of the Journal. The Committee on Science Teaching in the High Schools was after some discussion continued and the business session ended. The Academy then met in joint meeting with the North CaroUna Section of the American Chemical Society and heard several papers, after which the chemists and physicists held a joint session separate from the remainder of the Academy. After the reading of the last paper the Secretary reported that he had received a letter from Dr. E. W. Gudger, stating how much he had 10 Journal of the Mitchell Society [Dcceiitber appreciated the Academy meetings in the past and how much he missed them now that it was impossible for him to attend. He further- more stated that he would retain his membership, and extend his best wishes for a successful meeting. On motion the Secretary was in- structed to write Dr. Gudger, thanking him for his continued interest and good will. The Academy adjourned at 3 P. M. to meet at Chapel Hill in 11)22. Following is the present membership of the Academy. Those marked with an asterisk were present at the meeting. Andrews, William J., Civil Engineer Raleigh, N. C. Arbuckle, H. B., Professor of Chemistry, Davidson College Davidson, X. C. Babb, Josiah S., Dept. of Geology, University of North Carolina Chapel Hill Bahnson, F. F., 28 Salisbury Road Winston-Salem, N. C. Baker, Miss Lucretia, Meredith College Raleigh, N. C. *Balderston, Mark Guilford College, N. C. *Barnes, J. T., Dept. of Biology, Trinity College Durham, N. C. Barret, Dr. H. P., 211 Vail Ave Charlotte, N. C. Barrow, Miss Elva E., North Carolina College for Women Greensboro, N. C. *Bell, J. M., Smith Professor of Chemistry, University of North Car — Chapel Hill Binford, Raymond, President Guilford College Guilford College, N. C. Bonney, Miss E. C, 1421 Fourteenth Ave Hickory, N. C. Bottum, Miss F. R., St. Mary's School Raleigh, N. C. *Blomquist, H. L., Dept. of Biology, Trinity College Durham, X. C. Brewer, C. E., President Meredith College Raleigh, N. C. *Brimley, C. S., Division of Entomology, N. C, Dept. of Agriculture, Raleigh, N. C. Brimley, H. H., Curator State Museum Raleigh, N. C. Browne, Wm. Hande, Dept. of Electrical Engineering, State College, Raleigh, N. C. Bruner, S. C, Estacion Agronomica Santiago de las Vegas, Cuba *Bunitt, J. B., Professor of Pathology, Univ. of North Carohna Chapel Hill *Burch, Wayne, Trinity College Durham, N. C. Cain, William, Kenan Prof. Emeritus of Math., Univ. of N. C Chapel Hill *Campbell, Miss Eva G., Dept. of Biology, North Car. Coll. for Women, Greensboro Clapp, S. C, Superintendent State Test Farm Swannanoa, N. C. Cobb, Collier, Professor of Geology, University of North Carolina Chapel Hill Cobb, WiUiam B., Louisiana State University /Baton Rouge, La. *Coker, W. C, Kenan Prof, of Botany, Univ. of North Carolina Chapel Hill Collett, R. W White Hall, S. C. Couch, J. N., Biology Teacher, Charlotte High School, Charlotte, N. C. *Cunningham, Bert, Professor of Biology, Trinity College Durham, N. C. Davis, Harry T., Assistant Curator State Museum Raleigh, N. C. Denson, Lee A., U. S. Weather Bureau Raleigh, N. C. *Derieux, J. B., State College Raleigh, N. C. *Di.xon, A. A., State College Raleigh, N. C. Downing, J. S Elsmere, Del. 1921] Proceedings of the Academy of Science 11 *Edwards, C. W., Professor of Physics, Trinity College Durham, N. C. Farmer, C. M., 115 Orange St Troy, Ala. *rarrington, R. K'., Trinity College Durham, N. C. George,W. C. , Assoc. Prof . of Histology and Embryology, Univ. of N. C, Chapel Hill *Givler, J. P., Professor of Biology, North Carolina College for Women, Green.sboro *Gould, H. N., Dept. Biology, Wake Forest College Wake Forest, N. C. *Gross, Paul, Dept. of Chemistry, Trinity College, 1001 Trinity Ave. . .Durham, N. C. Groves, Miss Pattie J., 802 Watts St Durham, N. C. Gudger, E. W., American Museum of Natural History New York City *Haber, V. R., Division of Entomology, N. C. Dept. of Agriculture. .Raleigh, N. C. *Halverson, J. O., N. C. Dept. of Agriculture Raleigh, N. C. Hatley, C. C Durham, N. C. Heck, C. M., State College Raleigh, N. C. Henderson, Archibald, Prof, of Mathematics, Univ. of North Car. . . .Chapel Hill Hickerson, T. F., Prof, of Civil Engineering, Univ. of North Car Chapel Hill Hobbs, A. W., Associate Prof, of Mathematics, Univ. of North Car.. .Chapel Hill Hoffman, Dr. S. W Statesville, N. C. Holland, Miss Alma, Dept. of Botany, Univ. of North Carohna Chapel Hill Holmes, J. S., State Forester Chapel Hill Ives, J. D., Stetson University, Deland, Fla Pine Bluff, N. C. Ivey, J. E., State College Raleigh, N. C. *Jones, E. P., Trinity College Durham, N. C. Kilgore, B. W., Director of Experiment Station Raleigh, N. C. Krausz, H. B Raleigh, N. C. *Lake, J. L., Prof, of Physics, Wake Forest College Wake Forest, N. C. Lasley, J. W., Jr., Assoc. Prof, of Mathematics, Univ. of North Car.. . .Chapel Hill *Lehman, S. G., State College Raleigh, N. C. Leiby, R. W., Division of Entomology, N. C. Dept. of Agriculture. .Raleigh, N. C. Lewis, Dr. R. H Raleigh, N. C. Lugn, A. L., Dept. of Chemistry and Physics, Lenoir College Hickory, N. C. Mabee, W. Bruce, Div. of Entomology, N. C. Dept. Agriculture. . .Raleigh, N. C. MacNider, W. DeB., Kenan Prof, of Pharmacology, LTniv. of N. Car., Chapel Hill Marion, S. J., Dept. of Chemistry, State College Raleigh, N. C. Markham, Blackwell, 92 Toxtech St Brookline, Mass. Mendenhall, Miss Gertrude, 1023 Spring Garden St Greensboro, N. C. *Metcalf, Z. P., Prof, of Zoology and Entomology, State College. .Raleigh, N. C. ♦Mitchell, T. B., Div. of Entomology, N. C. Dept. Agriculture Raleigh, N. C. *Nowell, J. W., Wake Forest College Wake Forest, N. C. ♦Patterson, A. H., Professor of Physics, Univ. of North Carohna Chapel Hill Paull, N. M., Assistant Professor of Drawing, Univ. of North Car.. .Chapel Hill Pegram, W. H., 308 Buchanan Road Durham, N. C. Petty, Miss Mary, North Carolina College for Women Greensboro, N. C. ♦Phillips, Charles, Dept. of Pathology, Wake Forest College Wake Forest, N. C. Pillsbury, J. P., State College Raleigh, N. C. Plummer, J. K., 499 Courtland St Atlanta, Ga. ♦Poteat, W. L., President Wake Forest College Wake Forest, N. C. Powell, T. E., Jr., Professor of Biology, Elon College Elon, N. C. Pratt, J. H., State Geologist Chapel Hill 12 Journal of the Mitchell Society [December Prouty, W. F., Prof, of Stratigraphic Geology, Univ. of North Car.. .Chapel Hill *Randolph, E. E., Dept. of Chemistry, State College Raleigh, N. C. Randolph, E. O College Station, Tex. Randolph, Mrs. E. O College Station, Te.x. Rankin, W. S., State Board of Health Raleigh, N. C. ♦Rhodes, L. B., Div. of Chemistry, N. C. Dept. Agriculture Raleigh, N. C. Robinson, Miss Mary, North Carolina College for Women Greensboro *Roller, A. F., Science Teacher, Raleigh High School Raleigh, N. C. Ruffner, R. H., State College Raleigh, N. C. *Satterfield, G. H., Trinity College Durham, N. C. Saville, Thorndike, Assoc. Prof, of Engineering, Univ. of North Car., Chapel Hill Seymour, Miss Mary F., North Carolina College for Women Greensboro Shaffer, Miss Blanche E., North Carolina College for Women Greensboro Sherrill, Miss Mary L., North Carolina College for Women Greensboro Sherrill, Miss Mildred, Science Teacher, Henderson High School, Henderson, N. C. Sherwin, M. E., State College Raleigh, N. C. Sherman, Franklin, Entomologist, N. C. Dept. Agriculture Raleigh, N. C. Shore, C. A., State Laboratory of Hygiene Raleigh, N. C. *Shunk, I. v., 222 West Morgan St Raleigh, N. C. Smith, J. E., Iowa State College Ames, Iowa Smith, M. R., Science Teacher, High School Fort Mill, S. C. Smith, S. C, Dept. of Chemistry, University of North Carolina Chapel Hill Smithey, Ira W., Dept. of Chemistry, Univ. of North Carolina Chapel Hill *Speas, William E., Dept. of Physics, Wake Forest College Wake Forest, N. C. *Spencer, H., State College Raleigh, N. C. Stiles, Dr. C. W Wilmington, N. C. *Stuhlman, Otto, Jr., Assoc. Prof, of Physics, Univ. of North Car Chapel Hill *Sullivan, R. W., Dept. of Chemistry, Wake Forest College Wake Forest, N. C. Taylor, C. C, State College Raleigh, N. C. Taylor, Haywood M., Dept. of Chemistry, Univ. of North Carolina.. .Chapel Hill *Taylor, W. F., Wake Forest College Wake Forest, N. C. *Thies, O. J., Jr., Dept. of Chemistry, Davidson College Davidson, N. C. Totten, H. R., Dept. of Botany, University of North CaroHna Chapel Hill *Vann, H. M., Dept of Anatomy, Wake Forest College Wake Forest, N. C. Venable, F. P., Kenan Prof, of Chemistry, Univ. of North Carolina. .Chapel Hill *Wells, B. W., Dept. of Botany, State College Raleigh, N. C. *Wells, Mrs. B. W., State College Sta Raleigh, N. C. *Wheeler, A. S., Profes.sor of Organic Chemistry, Univ. of North Car. . .Chapel Hill Williams, C. B., State College Raleigh, N. C. *Williams, J. H., State College Raleigh, N. C. Williams, L. F., State College Raleigh, N. C. Wilson, Donald B., Dept. of Farm Crops, State College Raleigh, N. C. *Wilson, Henry V., Kenan Professor of Zoology, Univ. of North Car., Chapel Hill nVilson, R. B., Dept. of Biology, Wake Forest College Wake Forest, N. C. *Wil.son, R. N., Trinity College Durham, N. C. Winston, Dr. Lula G., Meredith College, 124 E. Edenton St Raleigh, N. C. Winters, R. Y., State College Raleigh, N. C. Withers, W. A., Dept. of Chemistry, State College Raleigh, N. C. 1921] Proceedings of the Academy of Science 13 *Wolf, F. A., Plant Pathology, State College Raleigh, N. C. *Wright, Miss Eva K., North Carolina College for Women Greensboro Total 133. The following papers were presented at the meeting: Age of Insects. Z. P. Metcalf. (Presidential address.) Appears in full in this issue. The Genus Raspailia and the Independent Variability of Diagnostic Features. H. V. Wilson. Appears in full in this issue. Current Research in Organic Chemistry at the University of North Caro- lina. Alvin S. Wheeler. Active work is being done upon six research problems. First, the nature of kelp oil from the distillation of kelp, a seaweed in the Pacific Ocean, is being investigated. Nothing whatever about it is known. Second, the bromination of 2-Amino-p-cymene yields a mono-bromo derivative and new compounds derived from it have been prepared. Third, the chlorination of 2-Amino-p-cymene also yields a chlorine derivative. The constitution of the two halogen compounds presents a fine puzzle in orientation. Fourth, further work is being done with Tribromojuglone as raw material. Fifth, the chlorination of juglone proceeds differently from the bromination and good results are being obtained. Sixth, a shorter process of obtaining bromo-amino-cymene is being sought, by brominating nitrocymene and then reducing. My assistants in these studies in the same order as the problems above are : H. M. Taylor, I. W. Smithey, I. V. Giles, T. M. Andrews, P. R. Daw- son, S. C. Smith. Some Fungi New to North America or the South. W. C. Coker. Sirohasidium sanguineum, another species of a rare genus of gelat- inous fungi which has been known before only from South America, has been found here. The author has previously reported S. Brefeldi- anum from Chapel Hill. A remarkable form of a well known edible mushroom, the early Pholiota (P. praecox), occurs in Chapel Hill and Raleigh. It is dis- tinguished by the absence of any visible trace of a veil. This would entirely mislead one as to its real place in classification, as the veil is supposC^d to be a generic character. The only species of the mushroom genus Tricholoma {T. venenata) that is known to be poisonous was collected at Chapel Hill in the fall 14 Journal of the Mitchell Society [December of 1919. This has been known before only from Michigan, where it made seriously ill seven people who ate it. A peculiar Httle mushroom of the genus Lepiota (L. caeriilescens) which turns a deep indigo blue all over when it dries has been found here. It has been known before only from Missouri and Ohio. Apodachlya hrachynema, a minute l)ut interesting and very rare mold growing on dead insects in water, has recently been found in Chapel Hill. It has been reported only once before from America, in Massachusetts. Notes on the Oecology and Life History of the Texas Horned Lizard. J. P. GiVLER. To appear in full in a later issue. Artificial Incubation of Turtle Eggs. Bert Cunningham. Chrysemys picta Herm. is recognized as a good species. C. mar- ginata Agassiz, C. cinerea Bonnaterre, and C. bellii Gray are all includ- ed under the specific name of C. cinerea. Chrysemys oregonensis Nut- tall, is also provisionally included under C. cinerea. In some of the experiments eggs laid in the usual manner w^ere used, but the majority of eggs were taken from the uterus. The latter showed a higher developmental rate. The fundamental requirements are proper moisture and temperature, and in the case of laid eggs they must be secured within a few hours of laying. Development may be stopped by low temperatures for a period of a month at least, and de- velopment of such eggs seems to proceed in a natural manner when brought back to a normal temperature. The artificial incubation allows one to keep a record of the incuba- tion time and thus secure a more graded series than is possible under natural conditions. It also makes possible much experimental work on the rate of development, inhibitors and activators. Some Considerations in Defense of the General Biology Course. J. P. GiVLER. To appear in full in a later issue. An Interesting Anomaly in the Pulmonary Veins of Man. W. C. George. In one of the anomalies found this spring in the anatomical labora- tory at Chapel Hill the blood from the upper left lobe of the lung was drained not into the left atrium but into the systemic circulation. A 1921] Proceedings of the Academy of Science 15 vein about a centimeter in diameter emerges from near the middle of the ventral surface of the upper left lobe and courses directly cephalad to empty into the left innominate vein. A short distance before it empties into the innominate this vein receives the accessory hemi-azy- gos vein. The right pulmonary veins and the pulmonary vein from the lower left lobe communicate with the left atrium as usual. Alfred Brown (Anatomical Record, 1913) has show^n that the pul- monary system in the cat arises from an indifferent splanchnic plexus in the region of the lung bud. This plexus has venous connections on the one hand with the sinus venosus and on the other with neighboring systemic veins (cardinals, segmentals, and others). Conditions simi- lar to those shown in the anomaly cited apparently arise as a result of some interference with the return of blood through the pulmonary portion of the embryonic plexus thus causing both pulmonary and bronchial blood to enter the bronchial veins and causing their great enlargement. In this particular case then the large vein draining the upper left lobe seems to represent the enlarged left bronchial vein and that portion of the accessory hemi-azygos between the innominate and the junction of the left bronchial with the accessory hemi-azygos. Due to the enlargement of the bronchial vein the accessory hemi- azygos appears to be a side branch of it. A More Phenomenal Shoot. William F. Prouty. At the last meeting of the North Carolina Academy of Science Dr. B. W. Wells described "A Phenomenal Shoot" which grew near Ra- leigh during the season of 1919. This shoot "grew from the stump of a beheaded tree of Paidownia tomentosa." The shoot described bj^ Dr. Wells was 7.75 inches in circumference at the base, had 20 inter- nodes and was 193^ feet in length. This shoot was supposed to have grown in one season, though this fact was not definitely known. During the past season the writer has witnessed the development of a shoot from a tree of the same species cited by Dr. Wells which surpasses in its dimensions the one above referred to. This shoot grew during this past season to a height of 21}^ feet. It has a circum- ference at base of 10 inches and has 24 internodes. One of the leaves, measured in the latter part of July, was 38 inches in largest dimension. This shoot grew in a clay-loam soil, residual from granite, on property adjoining the Campus, in Chapel Hill. The following papers were read but no copies or abstracts fur- nished: 16 Journal of the Mitchell Society [December A Photometric Study of the Fluorescence of Iodine Vapor. W. E. Speas. Breeding Results from Overwintering Cocoons of the Polyphemus Moth. C. S. Brimley. Neiv North Carolina Gall Types. B. W. Wells. Solid Culture Media with a Wide Range of Hydrogen and Hydroxyl Ion Concentration. F. A. Wolf and I. V. Shunk. Judgments of Length, Alass, and Time. A. H. Patterson. Effects of Desiccation on Cotton Seeds and on the Seed-horrie Element of Cotton Anthracnose. S. G. Lehman. Chlorination with the Silent Electrical Discharge. Paul Gross. The Electron, its Measurements and Applications. J. B. Derieux. Some Questions Concerning the Teaching of Physics in North Carolina. C. W. Edwards. Questions Arising from the Discovery of Occasional Vertebrate Herm- aphrodites with a Demonstration of a Case in a Pig. Harley N. Gould. The Anatomy of Angiopteris. H. L. Blomquist. Further Studies on the Pure Culture of Diatoms. Bert Cunningham and J. T. Barnes. Aphidius, a Parasite of the Cotton Louse. H. Spencer. Notes on the Salamanders of the Cayuga Lake Basin, N. Y., with Refer- ence to Eggs and Larvae. Julia Moesel Haber. A Method of Differentiating Mucous and Serous Cells. Eva Gal- braith Campbell. Recent Views on the Nutritive Qualities of Milk. J. 0. Halverson. Relationship of Temperature and Relative Humidity to the Distribution of Cockroaches. Vernon R. Haber. From Egg to Frog in two Months. H. V, Wilson. The following papers were read by title only, in the absence of their authors: On the Polyembryonic Development of the Parasite, Copidosoma gelechiae. R. W. Leiby. The Lorentz Transformation in Einstein Relativity. Archibald Hen- derson. The Inheritance of Economic Qualities in Cotton. R. Y. Winters. Notes on Recently Discovered Miocene Whale. William F. Prouty. The following paper was transferrred to the Chemical and Physical program : Ionizing Potentials of Gases by Negative Electrons. A. A. Dixon. C. S. Brimley, Acting Secretary. JOHN FRANCIS LANNEAU 1836-1921 A long and variously distinguished career came to a close when John Francis Lanneau died in Wake Forest, March 5, 1921. He was born of Huguenot parentage in Charleston, South Carohna, February 7, 1836. His father was Charles Henry Lanneau, his mother, Sophia Lanneau. He was graduated from the South Carolina Mihtary Academy in 1856. His teaching career began at once in 1857 as tutor in mathematics, and from 1858 to 1861 as professor of physics and chemistry, in Furman University, Greenville, S. C. Then came the Civil War in which he served four years first as Captain of cavalry in Hampton's brigade, later as Lieutenant and Captain of engineers. At the conclusion of the war he resumed his connection with the Fur- man faculty, being professor of mathematics and astronomy from 1866 through 1868. For the next four years he was professor of mathe- matics in Wilham Jewell College of Missouri. In 1873 he accepted the presidency of the Alabama Central Female College, Tuscaloosa, holding that position for six years. From 1879 to 1888 he was pres- ident of the Baptist Female College, Lexington, Missouri. The next two years he was president of the Pierce City Baptist College of the same state. In 1890 he accepted the professorship of physics and ap- plied mathematics in Wake Forest College. From 1899 to his death he was professor of applied mathematics and astronomy. The honorary degree of M. A. was conferred upon him in 1869 by Baylor University, LL. D. in 1915 by Furman University. Of striking physique and courtly bearing Dr. Lanneau won at- tention and respect wherever he appeared. He was of the finest type of the Christian gentleman and up to the day of his death was chair- man of the board of deacons and treasurer of the Wake Forest Bap- tist Church. Apart from the immediate tasks of the class room. Dr. Lanneau showed his deep scientific interest in several ways. He was probably the first man in North Carolina to give demonstrations and public lectures on the X-rays. In 1907 he invented the Cosmoid manu- factured by Wm. Gaertner & Co., of Chicago, and described by him in "Popular Astronomy," December 1913. It is an ingenious ap- paratus for illustrating many astronomical conceptions and motions. [17] 18 John Francis Lanneau [December It is capable of numerous and easy adjustments. He was an active member of the North CaroUna Academy of Science and of the Astro- nomical Society of the Pacific. A list of his scientific papers is appended: The Source of the Su7i's Heat. Popular Astronomy 14: 410. 1906. Also pub- lished in Journ. E. M. Sci. Soc. 22: 45. 1906. The Sparsity of The Stars. Popular Astronomy 15: 390. 1907. Sirius, the Bright and Morning Star. Popular Astronomy 19: 393. 1911. The Cosmoid. Popular Astronomy 21: 613. 1913. The Sun 's Eclipse of June 8, 1918: Question. Popular Astronomy 26 : 299. 1918. Also published in Journ. E. M. Sci. Soc. 34: 76. 1918. Sunspots in July, 1903. Popular Astronomy 11 : 372. 1903. Physics of Shooting Stars. Popular Astronomy 13 : 434. 1905. Approaching Sun-Spot Maximum. Journ. E. M. Sci. Soc. 20. 21. 1903. Wm. Louis Poteat Charles E. Brewer, H. V. Wilson. JOHN FRANCIS LANNEAU 1836 1921 THE AGE OF INSECTS. By Z. p. Metcalf Geologists are in the habit of speaking of this as the "age of man" or the Psycozoic era. From this stated opinion I wish to dissent, for this evening at least, and call your attention to the fact that while we as humans may speak of this egotistically as the "age of man" it is not the age of man but the age of insects in which we are living. Man may try to dominate this age but on every hand he finds his efforts thwarted and at every point he must give way to numerous hordes of insects whose chief aim seems to be to overthrow the kingdom of man on this world. The late unpleasantness in Europe is remembered by our soldiers, not so much as a war on the Boche, as a war on in- numerable insect pests denominated cooties. And even those of us who had no chance at first-hand knowledge can sympathize with the young Canadian who, when he was decorated with some medal or other for outstripping his fellows in a charge, remarked that his in- terest in the matter was not in the charge but in the hope that he could run fast enough and far enough to escape the cooties. As in war so in peace, on every hand we find our lives circum- scribed and our efforts limited because of the presence of numerous insect pests. Our crops, our domesticated animals are increasingly subjected to their attacks. Our forests are devastated by them. Our houses and our stores are destroyed by them. Our books and our paintings are marred by them. Whole regions of the world are prac- tically unfit for human habitation because of the diseases they carry, and human want and human suffering abound in all quarters because of these troublesome httle pests. In fact, they have so adapted them- selves that it is impossible to think of any relation of human life and human culture that is not colored in some way by insects, yea even as pointed out below our very existence is dependent upon them. It would seem logical, therefore, that anything that touches us so vitally ought to be pretty well understood. Yet, I believe I am safe in saying that there is no group of animals so little known, to zoolo- gists even, as insects. This in spite of the fact that more of our zoolo- gical literature, each year, is devoted to insects than all other animals combined. Whole regions of the insect kingdom are still unsurveyed and, while we know a little about the external anatomy of a few forms, our knowledge of the internal anatomy is still largely based on the [19] 20 Journal of the Mitchell Society [December work of Swammerdam in the seventeenth century, who worked with- out a compound microscope or a microtome. Our knowledge of the ecological relations is largely based on superficial studies of the life histories of isolated species and all the rest is sweeping generalizations that are almost certain to fail in the acid test of real ecological experi- ments. Our knowledge of insect vectors of human, animal, and plant diseases are equally poorly grounded on the knowledge that the tsetse fly carries sleeping sickness, that the malarial mosquito carries ma- laria, that the cattle tick (not an insect) carries Texas fever, and a few other cases from which we generalize often wisely, if not too well. We are often guilty of orating, sometimes rather loudly, I am afraid, about the damage done by the gypsy moth, or the boll weevil or what not, but do we even stop to ask ourselves about the remarkable interplay of physiological processes between plant and insect or the ecological relations between the insect and the host of conditions that surround it? And the echoes answer, "Do we?" If this then is the condition among our professional zoologists (I believe entomologists are still regarded as zoologists by the layman, if not so regarded by his fellow zoologists), what is the condition among other scientists, and other folks in general, — that great class to which we scientists refer frequently, and not without condescension, as the lay minds, as something separate and entirely distinct from our minds which are denoted as academic minds. It is in the hope that Tmay be able to educate the lay mind that this paper has been prepared. And for fear that some of you may miss the drift of my remarks, I hasten to remind you that you are the lay mind, and to add that I am not exactly clear as to just why you are the lay mind or just what makes my mind, entomologically speaking, an academic mind, while from the standpoint of the chemist or the physicist or the botanist or what not my mind is removed from its temporary and somewhat in- secure pedestal and is laid at the base and becomes perforce a lay mind. Perhaps I would feel just as well and you would have more respect for what I have to say if I did not inquire too closely into this phase of the subject but hasten on to tell you something about bugs, as I see that you are all sitting somewhat breathlessly with open mouths, if not with open minds, to learn something about this field that we call en- tomology and about this age that we call the age of insects. Before I proceed, however, I must warn you that I am not an en- tomologist, let alone a zoologist, although I believe that is the title 1921] The Age of Insects 21 that is conferred upon me by powers vested in the State of North Carolina and the government of these United States, but a speciaUst in an obscure group of insects. I tell you this to defend myself against the hordes of speciahsts in other groups who may hold up their hands in holy horror at some of the generalizations that I may make. Now the specialist is a sort of rare bird whose words are a law unto himself, at least, and who knows so much about his own pet field that he knows nothing about anything else and his final defense in all arguments about his field is, ''Well, I am the specialist in this group. " To which some of you, who are broadly academically minded if not lay minded, must feel like exclaiming, "We are thankful for that much at least." The difference in those things is of course one of degree. For instance a student of insects is, naturally, an entomologist but a student of fleas is a Professor of Suctoria, the student of the hind leg of a flea is a pulicidid morphologist and the student of the hairs on the second joint of the hind leg of a flea is a speciaUst and I say it reverently, "May the Lord help him!" With this rambhng and somewhat generalized introduction, you will pardon me if I turn your attention to some of the various aspects of the insect world in order that we may examine them more closely. Emerson said something to the effect that fools are amazed at the ex- traordinary and wise men wonder at the ordinary. I shall presume therefore on your wisdom and use only ordinary examples with which to paint my picture of the insect world. The Number of Insects in the World The possible number of insects in the world has always been a sub- ject of very great interest to me. I, of course, refer to the number of kinds or species not to the number of individuals. No one has been foolhardy enough to make a personal census of insect individuals as yet, I believe. The nearest approach to this are the statements that mis- guided sanitarians and others make, sometimes, to the effect that starting with a single pair of houseflies we would have, by the end of summer, so many quintillions of flies. We all know this is not true, save perhaps on a summer afternoon when we are trying vainly to get our allotted forty winks and all but succeeding because of several of the above mentioned quintillions that persist in lighting just to the windward of an upturned nose. Or there is the statement that start- ing with a single plant louse, with all of her descendants surviving, we 22 Journal of the Mitchell Society [December would have, in a year or two, a mass of plant lice equal in volume to our earth. This may or may not be true, but if true a large proportion of the descendants must fly away to other worlds than ours because any species is lucky indeed if it ends its fiscal year and balances its books with a definite increase in numbers over the previous year. The question of the number of species of insects is, however, an- other matter. We see, in our text books, estimates of the number of species of insects in the world, at anywhere from 250,000 to 500,000 and 1,000,000 and recently some one ventured to estimate that there must be at least 10,000,000 kinds of insects in the world, at the pres- ent time. Obviously, in trying to generalize about a group of animals with such an enormous number of species, one finds himself handicapped not from lack of material but from its very superabundance. General Physiology. Typically, an insect is an arthropodous animal with its body di- vided into three parts; head, thorax and abdomen, and with three pairs of legs and usually two pairs of wings. Being an arthropod, an insect carries his skeleton on the outside of his body and as he grows this skin which is hard and chitinous must be cast off and a new skin produced to accommodate the larger sized individual. This skeleton is segmented to provide free movements. Thus various parts have been separated and since these parts are fairly constant they have been much used in taxonomy. But their phylogenetic relations are not always clear and thus a special nomenclature has grown up around each group which has served to discourage all but the most highly specialized of the specialists and has acted as a sort of natural selec- tion, thus cutting down materially the crop of speciahsts, much to the general benefit of the world at large. With these special parts we need not concern ourselves here but the generalized parts will bear closer inspection. The head is largely sensory in function and bears the compound eyes, simple eyes and antennae. These will be dis- cussed more in detail under sense organs. The head also bears the mouth parts which are among the most complicated structures found in the animal kingdom. Primitively, they consist of no less than three paired and three unpaired structures. We cannot inquire into the various morphological variations but the following classification of the mouth parts of insects based largely on functional grounds will 1921] The Age of Insects - 23 perhaps aid in conveying the complexity of the subject. We have, as our most generahzed, the chewing insects which are fitted with a pair of mandibles which tear and masticate food. A scraping type which lacerates the epidermis of plants and sucks up the exuding sap. A piercing type in which the mouth parts are fitted for piercing the skin of an animal or the epidermis of a plant and sucking the blood or sap. A rasping type fitted for rasping off solid particles and dissolving them in saliva and then sucking up the resultant hquid. A sponging type in which the mouth parts are fitted for sponging up exposed liquids. A siphoning type in which the mouth parts are formed into a long hollow tube which is usually used to suck up exposed nectar. A lapping type in which the mandibles are well developed for work- ing wax and paper or for portage and the other mouth parts are modi- fied into a tongue which is used to lap up exposed liquids. The thorax is largely given over to locomotion, which is carried on by the wings and legs. The insects were without doubt the first ani- mals to conquer the air and of all animals, birds not even excepted, their mastery of the air is the most complete. The legs are fitted chiefly for walking, running, leaping and grasping. The speed of certain of our insects is indeed remarkable, as is their ability to make surprising leaps. The world's record for the broad jump is not held by a man but undoubtedly belongs to the flea. A leap of a hundred times his length would be no astounding feat for a flea, whereas for man five or six times his length would be wonderful indeed. In the same way the muscular strength of insects is almost beyond belief. The weakest insects according to Plateau can pull five times their own weight, while the average is more than twenty times, and one of the leaf beetles can pull forty-two times its own weight. In contrast man cannot pull his own weight and under the same conditions a horse could pull but three-quarters of his weight. Some of the insects are able to push one hundred times their own weight, while the honey bee can carry a load equal to three-fourths of its bodily weight. These remarkable feats are accounted for by the small size of the insects and by the greater advantage in leverage from an external skeleton. Passing to the internal organs we find time for the discussion o two systems of organs only. The first of these is the respiratory or 24 • Journal op the Mitchell Society [December gans or trachea. The insects differ from man in that their circulatory organs are very poorly developed and their respiratory organs are well developed to counterbalance this. The insects have no lungs but a system of trachea or tubes which open to the exterior through minute pores called spiracles. From the spiracles the trachea branch and re- branch until they reach all parts of the body. The oxygen is carried to the cells through these tubes and the carbon dioxide carried away through the same set. The nervous system and sense organs of insects are so different from those of man that we are often at a loss to account for the sensory hfe of insects. There is in the insects no brain as we find it in the verte- brates but the nervous functions are distributed to a chain of ganglia along the ventral wall of the body. There is therefore more or less of local control for each region of the body. The psychic life of such animals is therefore rather low and in no way to be compared with that of man. The sense organs of insects may be grouped into three classes (Comstock) : Mechanical sense organs. — ^Touch and hearing. Chemical sense organs. — Taste and smell. Organs of sight. Touch organs are generally distributed over the body and need no special discussion. Organs of hearing are apparently not universally present. They occur among the singing orthoptera and in mosquitoes and perhaps in bees, but whether they occur in other forms is by no means clear. In the grasshopper the ears are located on the first seg- ment of the abdomen, but in the katydids and crickets they occur on the tibia of the fore legs. In the mosquitoes they undoubtedly occur on the antennae, as the antennae are provided with whorls of setae which gradually decrease in length from the base of the antennae out- ward. It has been demonstrated that these setae vibrate to notes of different pitch and it is believed that the vibrations are transferred to the nerve endings. Most beekeepers believe that bees can hear be- cause they make such different hums under different circumstances, and even an amateur can tell the difference between the ])usy hum, the swarming hum, and the angry hum of an outraged bee. The chemical senses of insects are very poorly understood. This is due in part to the wide distribution of these organs over the body and to the fact that several different types of sense organs are fre- quently closely associated. We say that insects taste because we 1931] The Age of Insects 25 know they make selections in foods, and we say bees smell because they seem to be able to distinguish members of their own colony from other bees, and they seem to be able to recognize their queen and to distinguish drones. The sense of sight in insects is taken care of by two distinct types of eyes, the simple eyes and the compound eyes. The former we be- lieve is used chiefly to distinguish light from darknees while the latter is used to give an image. The compound eyes of insects are composed of from a few to many hundreds of hexagonal prisms, called ommatid- ia. It is believed that each ommatidium forms a portion of the image just as tiles are put together to form a mosaic. Or, since the ommatidia are hexagonal in shape, perhaps we can best compare the image that insects receive to the image our eyes receive when we look through a piece of glass which has been laid down on poultry netting. Each mesh of the poultry netting would contribute its portion to the image just as each ommatidium of the insect's compound eye does. Obviously such an eye is better adapted to seeing motion than it is to seeing distinct images. Insect Psychology. I wish I had the agile mind and the facile pen of a Fabre so that I would be able to unfold for you some of the beauties of the instincts of insects. We may see striking illustrations on every hand. Why do certain insects always lay their eggs in such situations that their young will find an abundance of food at hand? This question is of course easy to answer in the cases of those insects whose adults feed on the same plants as the young. It is simply a matter of placing them in the most convenient place; but we are confronted with the query, why do some of these insects take such elaborate pains to con- ceal their eggs by placing them in the stems of plants or imbedding them in the tissues of the leaves? On the other hand we are confronted by that vast host of adult insects which lay their eggs on food plants or animal hosts upon which they themselves do not feed. Or we are con- fronted by that compHcated set of reactions, so well illustrated by our solitary wasp, where a nest is constructed and prey is searched out and stung in the precise spot to paralyze the individual but not cause its death. Then the prey is dragged back to the nest and stored with an egg and the nest closed and concealed. Or we see an insect like the cornfield ant taking the eggs of the corn and cotton root louse into its 26 Journal of the Mitchell Society [December nest and storinj^ them through the winter, shifting their position in its tunnels with the changes of the temperature so that it will not be in- jured, then hatching the egg in the sun in the spring and placing the young nymph on the proper food plant. All this in order that the ants' descendants may have an abundant supply of honey dew for their nourishment. What are the mental processes of the eumenes wasp as it fashions the clay into pottery of the most charming design — a design so artistic that man has copied it as his very own. What arc the mental processes of the tiny caterpillars as they weave their mar- velous gossamer threads and become the earth's first aeronauts? What are the fungus ants thinking about as they prepare a fertile field and sow upon it the spores of a certain species of fungus in order that their children may have an abundance of food? What of the mental processes of the scarab as it rolls its ball of dung often many weary in- sect miles in order to provision its nest for its larva? Why does each species of scarab store its nest with the clung of certain animals only? What is the psychological process of the queen bee that causes her to lay only unfertilized eggs in drone cells? What are the slave-making ants "thinking about" when they make a raid on the nest of another species, kill the adults, kidnap the larvae and pupae, carrying them away to their nests where they are raised to adults to serve their cap- tors? We see these questions about us every day and we ask the question "Why?" and we reply very wisely with the magical word "instincts." Which is a very learned and very scientific way of saying that we know nothing about it. In ordinary speech, the word "instinct" stands for all the heredi- tary and automatic revelations of activity, from simple tropisms to the most complicated outward manifestations of individual memory. In- stinctive acts are stereotyped, being ever the same when responding to stimuli of the same nature, and almost always adapted to their ob- ject, although not resulting from previous experience on the part of the individual. To define them more precisely is impossible for they are varied and complex, overlapping one another and often becoming so confused as to render difficult the tracing of their limits. Neverthe- less, we should not place them all on the same level and attribute to them all a common origin. Tropic reactions are due to the properties of living matter, rhythms presuppose an organic memory and hence a period of education, ancient or recent; but this apprenticeship is purely mechanical and dependent upon the stimuli that produce it. 1921] The Age of Insects 27 Apprenticeship has its part also in those manifestations of mem- ory belonging to the species which play such an important part in the behavior of arthropods. This kind of memory presents a character of distinct superiority, inasmuch as it was made effective for the race by the distant ancestors of the individual in the guise of a choice between the various possible responses of differential susceptibility. Choice, of a remarkably intellectual nature, is even more noticeable in the instinctive manifestations of individual memory. The animal, endowed with well-developed senses and nervous system, not only re- acts to new necessities by new acts, but associates the stored impres- sions of new sensations and thereby appropriately directs its further activities. Thus, by an intelligent process, new habits are estabUshed which by heredity become part of the patrimony of instinct modifying the latter and constituting elements essential to its evolution. Of these instincts acquired through an intelligent apprenticeship Forel was led to say that they are reasoning made automatic and it is to them particularly that we may apply the idea of certain biologists that instincts are habits which have become hereditary and automatic. Probably all superior instincts at first had this intellectual quality. This certainly is true of all such as originated from more or less slowly acquired habits; it seems to be the rule as well with instincts due to mutations. It stands to reason that, whether they result from a sud- den psychic change or from a sudden organic modification, these in- stincts must always be preceded by some intelligent period of educa- tion, during which they become perfected, in order to be handed on to posterity and to assume the character of true instincts. Here, then, we are confronted with several classes of instinctive acts, which differ not only in origin l)ut also in intellectual characteris- tics. No doubt they are linked together by many intermediate mani- festations, and in the animals with which we are now concerned they often blend the one with the other or even with the reflexes, on ac- count of the profound differentiation of nervous and sensorial centers. It is, nevertheless, very difficult to consider them as manifestations of a special faculty which we would fain place on the level of intelligence by calling it instinct. The name instinct justly applies to certain forms of activity which are innate and automatic, but these forms pro- ceeded in diverse ways from the vital energy which is the source of all organic activity, and the highest of them, which are at the same time the most striking ones in the animals here studied, were originally acts more or less requiring the exercise of true intelligence on the part of 28 Journal of the Mitchell Society [December sjiocies and individuals. Intelligence has no part in the development of the instinct that draws nocturnal Lepidoptera toward the light, nor has it doubtless anything to do with the rhythms through which organic memory manifests itself. But intelligence it is that regulates by appropriate selection all manifestations of race memory; intelli- gence again in the sundry forms of association and individual memory, that puts together the most complicated mechanisms of instinct. Instincts are of various kinds. If, by the word instinct we under- stand not any one special faculty but the complex of all the instincts, namely, the innate automatism regardless of its origin, we can say with Bergson that instinct and intelligence "are not things belonging to one and the same order, " that they "diverge in direct ratio of their development," but that "they never become completely separate." They are both "opposites and complements" and they assist one another. "On the one hand, indeed, the most perfect instincts of the. insects are accompanied by certain gleams of intelligence, be it only in the choice of place, time or material of construction. When by ex- ception bees build their nest in the open they invent arrangements which are new and in the true sense intelligent to meet the new con- ditions. On the other hand, intelligence has still more use for instinct than instinct has for intsUigence, since the ability to work up raw material presupposes in the animal a superior grade of organization, to which it could have arisen on the wings of instinct only." Before such evidence as this Fabre was forced to modify his theory of immu- table instinct. "By itself, mere instinct," says he, "would leave the insect disarmed in the perpetual conflict of circumstances. A guide is needed in the midst of this bewildering melee. That the insect has such a guide is evident to a high degree. This is the second domain of its psychic powers. Here it is conscious and susceptible of perfect- ing by experience. As I dare not designate this rudimentary aptitude by the name of intelligence, a title too noble for it, I shall call it dis- cernment." But is discernment in this sense not really a form of in- telligence? Such is the measure in which instinct and intelligence are com- bined in animals. If, following Bergson, we admit that consciousness "is proportional to the power of selection at the animal's disposal," it will be quite evident that consciousness must be particularly ob- scured in all purely instinctive acts, but that on the contrary it must accompany all intelligent acts. Bergson, however, regards con- sciousness in a peculiar light, since he considers it as "life projected 1921] The Age of Insects 29 through matter," as the common source from which sprang in different directions both instinct and intelligence. This view leads us away from the commonly accepted theory that consciousness must be con- sidered as that inmost luminary which enlightens our actions. It is possible, even probable, that this kind of consciousness exists to a greater or lesser extent in the animals. However, we can not know anything about it, and we believe with Ed. Claparede that "the science of animal psychology may and must scrutinize the problem of the greater or less intelligence of animals without being concerned about their consciousness." We discern intelligence in its simplest expression wherever we notice a choice between the various alternatives offered by circum- stances, and in one of its highest forms wherever we observe that pow- er of invention which, according to Bergson, enables the human race to "manufacture artificial objects, more particularly to make tools with which to make other tools and to vary their fabrication indefi- nitely." These two extreme forms are naturally connected by a series of links, and we know that the one as well as the other plays a part in the behavior of arthropods. The latter of the two seems, how- ever, to be rather exceptional in our group, showing itself only in the primitive state consisting of the use of foreign bodies as implements. The tool used by Ammophila is a small stone with which the female rams and packs the dirt that closes her burrow. With certain ants of India {Oecophylla sinaragdina) and of Brazil {C am/ponotus texter) the instrument consists of the larva of the species itself. Held between the mandibles of the workers, these larvae, by means of their thread, glue and fasten edge to edge the leaves of which the nest is constructed. The implement of the crabs, of the genus Melia, in the Indo-Pacific seas, is supplied by a delicate sea-anemone. This is held between the pincers of the animal, which probably uses the nettling exudations to paralyze its prey. Facts of this nature are rare in the world of arthropods, but they have an important significance. The use of the little stone is not yet a fixed habit wdth Ammophila, it belongs only to certain individuals more highly endowed than others and is perhaps only accidental even with them. Maybe it will finally pass into the instinctive habits of the species; for the present it belongs to the domain of individual in- telligent acts. The crabs of the genus Melia are already farther ad- vanced, all the species carry anemones and all exhibit a curious modi- fication of the pincers, the fine teeth having become elongated and 30 Journal of the Mitchell Society [Decemhe needlelike so as to give them a better hold on their guest and tool. That they are adapted to the latter is evident, yet this adaptation is not such that the crab is likely to be in serious danger when it has not its Actinia. Many of the Melias brought back by explorers are not provided with anemones, and we may believe that the presence of this implement guest is not yet of vital importance to the species of this peculiar genus. The case of the ants which use their larvae as needles is quite different. With them this singular habit is innate and specific. Though probably acquired through intelligent acts, it now belongs entirely to the domain of instinct in the species among which it prevails. And thus we always come back to that predominat- ing fact of the psychological history of arthropods, namely, the trans- formation of intelligent acts into instinctive acts. The following con- siderations formulated by Bergson eminently apply to this group: Among animals, invention is never more than a variation on the theme of routine. Locked up as it is within the habits of its species, the animal succeeds no doubt in broadening these by individual ini- tiative; but its escape from automatism is momentary only, just long enough to create a new automatism; the gates of its prison close as soon as they are opened; dragging the chain merely lengthens it. Only with man does consciousness break the chain. Man occupies the topmost place in the scale of vertebrates, for, breaking the bonds of instinct he insures thereby the complete expan- sion of his intellect. Insects especially Hymenoptera hold the same dominating position in the scale of arthropods where they are the highest achievement of instinctive life. These two groups represent the actual extremes of the two paths followed by psychic evolution in the Animal Kingdom; the arthropods are going toward instinct, the vertebrates toward intelligence. These two courses are quite op- posite, but why have they diverged? At the beginning of their evolu- tion, during that far distant epoch when they were differentiating along four main lines (echinoderms, moUusks, arthropods, and verte- brates), animals were threatened by a great danger — "an obstacle" says Bergson, "that doubtless almost checked the progress of animal life. There is a peculiarity which we can not help being struck by when we glance at the Paleozoic fauna. The moUusks at that time were more universally provided with shells than those of today. The arthropods in general were provided with a carapace. The oldest fishes had a bony covering of extreme hardness." But "the animal which is shut in a fortress or in a coat of mail is condemned to an exist- 1921] The Age of Insects 31 ence of half-sleep. It is in this torpor that the echinoderms and even the mollusks are living today. The arthropods and vertebrates escaped from it and on this happy circumstance depends the present development of the highest forms of life. "In two directions, indeed, do we see the impulse of active life re- gaining the upper hand. The fishes exchange their ganoid armor for scales. Long before them the insects had made their appearance, having also rid themselves (of most) of the armor that once protected their ancestors. In both groups the inefficiency of the protective en- velope was compensated for by a nimbleness that enabled them to escape their enemies and also to take the offensive and to select the place and time of the encounter." These remarks rest on a solid foundation but they should be mod- ified in one particular which is of paramount importance in the ex- planation of the structure and the special psychology of the arthro- pods. These animals have never lost the chitinous armor that pro- tected their primitive ancestors. They have preserved it in its en- tirety and with greater or less thickness. Coleoptera, crabs, scor- pions, and thousand-legs of our times are by no means inferior in this regard to the ancient forms from which they are descended. As a matter of fact they are covered today, as in times of yore, with an external skeleton of chitin. That is why Edmund Perrier, in his desire to emphasize their dominant character, has called them Chitinophores. To escape imprisonment within their protective en- velope, to acquire the flexibility and mobility necessary to their evolu- tion, they underwent certain superficial modifications. These con- sisted in the division of the armor into several pieces by means of artic- ular lines, along which the chitin is less thick than elsewhere, thus allowing the pieces to move one upon the other. This is the very waj^ in which they became arthropods, at once acquiring agility without losing their protective cover. Naturally such joints were formed wherever the several segments, arranged in a row and constituting the body of the animal, came together. As a result, these segments ac- quire a certain independence and their uniformity is to a certain ex- tent preserved. Indeed, we see that many arthropods possess a pair of appendages on each segment (Myriapods and the majority of Crus- taceans) and that the insects most remote in this regard from the primitive types are still provided with seven pairs of appendages (one pair of antennae, three pairs of buccal appendages and three pairs of legs) not to speak of the modified or rudimentary organs to be seen on 32 Journal of the Mitchell Society [December the different parts of the abdomen. And the chitinous envelope of these appendages has broken into joints in the same manner in which the body itself became annulated. Hence the name of arthropods which is given to these animals. What a difference from the vertebrates. Their skeleton becomes an internal framework. The organism is thus allowed to attain great- er dimensions; the segments are able to fuse to a greater degree and to lose more or less their independence; all of which results in the re- duction of the number of limbs to only two pairs. Now, the relative independence of the segments and the multi- plicity of the appendages have as a corollary the differentiation of these structures, each of which plays a special part in the organism. As Bergson remarks, the various appendages of arthropods are as it were natural implements, which differ from each other in structure as well as in function. Their specialization may be carried so far as to have each part of a single organ perform a separate function. This is clearly seen in the bee, in which the first tarsal joint of the hind legs is transformed into a brush, the tibia into a pollen basket, while the two joints, by the contact of their edges, act as pincers which take up the flakes of wax secreted under the abdomen. It is an admirable instrument wonderfully adapted to the performance of its particular tasks. As a general rule, apart from the changes which they may undergo in the course of specific evolution, the appendages of arthro- pods are unchangeable in the individual and are narrowly adapted to certain purposes; they are the tools for instinctive work, and in this they differ from the less specialized but more generally useful limbs which serve as implements to the vertebrates, at least to the higher vertebrates. With these latter, as Bergson expressed it, the two pairs of limbs "perform functions much less strictly dependent upon their forms," acquiring complete independence in man, whose hand can do any kind of work. "It seems, then, that the extraordinary preponderance of instinc- tive activity among the arthropods has as its essential reason the dif- ferentiation and the multiphcity of the appendages, in other words, the chitinization of the integument and the formation of joint lines which results from it. From the beginning these animals were doomed to use organic instruments, and they made the best use possible of these. Their main psychical task consisted in engraving upon their memory and in instinctively repeating the acts to which these organs were adaptable." (Bouvier.) 1931] The Age of Insects 33 Or we follow a bee as it leaves its hive and visits flower after flower and when it has gathered its load of sweets it takes a "bee line" for the apiary and when it gets there it goes directly to its own home with- out any mistakes and we talk very wisely and knowingly about the ''homing instincts of the bee, " but do not be led into believing that we really know anything about it. Because I am afraid that about all we know is to laugh at the poor Swiss peasant who paints the fronts of his hives in fantastic design so that his bees will find the right hive. Perhaps he laughs best who laughs last and the Swiss beekeeper may be right after all. Who knows? When we contemplate the marvels of colonial life among the in- sects and the paucity of our knowledge of the warp and the woof of the intricate pattern that they make, we are filled with admiration of the blind Huber who taught us so much of the psychology of the bee. The intricacy of the problem is appalling but when we consider the benefits that might accrue to the beekeeper by their solution we are more inclined to buckle down to work and renew our efforts to solve them. No wonder we feel like exclaiming with Maeterlinck: "The in- sect does not belong to our world." The other animals, even the plants, notwithstanding their mute existence and the great secrets which they jealously guard, do not seem wholly strangers to us. In spite of everything we have a certain feeling of terrestrial kinship with them. They may surprise, nay, astonish us, but they fail to upset the very foundations of our concepts. The insect, on the other hand, displays something that seems incongruous with the habits, the morals, the psychology of our globe. Apparently it comes from another planet, more monstrous, more vigorous, more demented, more atrocious, more infernal than ours. Vainly does it seize upon life with an au- thority and a fecundity unequaled here below; we can not accustom ourselves to the idea that it is part of the scheme of that nature of which we fondly believe ourselves to be the favorite children. With this amazement and this failure to understand is mingled, no doubt, a certain instinctive and profound feeling of dread imparted by these beings so incomparably better armed and equipped than ourselves, these containers as it were of compressed energy and activity which we vaguely feel to be our most mysterious enemies, our final competitors, and perhaps our survivors. . 34 Journal of the Mitchell Society [December Life Histories. The general phases of the Hfe histories of insects are usually well known but even here we find that there are many popular misconcep- tions. McCormack tells of a physician who laughed at the notion that house flies are but one stage of maggots for said he, "Have I not often seen little flies coming out of the ground in the spring." One of our largest potato growers believed that I was trying to fool him when I told him the "soft shelled potato bug" is but the grub of the "hard shelled potato bug" and he was not convinced until he had tried the thing out and carried the grubs through their changes to pupae and then to adults. Afterwards he said to me, "That is the most valuable lesson I have ever learned on the farm, for it has taught me that I have not seen what is about me every day." We are inclined to smile at the ignorance of people in general as outlined by such examples as those quoted above but before we allow our smiles to become too broad perhaps it would be better to inquire into our own knowledge. We know or think we know the life his- tories of a few insects scattered from one end of the insect kingdom to the other but this knowledge is based chiefly on the study of a few economic forms. And too frequently these life histories have been worked out in our more northern states and apply only imperfectly or not at all to our southern conditions. The wonders in the adaptations for carrying on the life cycle of in- sects are almost beyond belief and I wish that I had the space to re- count many of them but time will permit citing only a very limited number. The time involved in completing a life cycle is apparently as varied as the species of insects themselves. I need only remind you of the cicada on the one hand, whose cycle covers seventeen years, while on the other hand we have the house fly with a complete cycle every nine to fourteen days, in the warmer parts of the year. The complexity of the cycle is also very much involved. We have insects like the fish moth with no changes or metamorphosis on the one hand while on the other we have forms like the blister beetles with no less than eight distinct stages in its cycle. Between these two ex- tremes are all grades of forms with almost every conceivable relation. The following table will make these relations clearer than they would otherwise be: 1921] The Age of Insects 35 CO O w O m o ''I m ;z; o H •3 -(-^ 3 ;^ o -5 -3 < TS <: Ol H K MOULT 12 1 O M ,faC bC W w j^ 'c c « 1 '■+3 a 03 03 ^ § &< ^ ^ ^ ^ SEVERAL MOULTS * O o O bJD S ■ 0 .2 o3 H Ch 0 >i 'S 03 Pi a >H ^ 2; yA HATCHING < ^ M M) bC bC m ^ bC bC bC b£ ^ 2 W W w W 1— ( bC §3i CO ►J 0 3 .2 a: g 0^ 03 « !B ■ — 1 « < > 03 i3 03 +J !^ !.; os ^ w X 0 W Q « ^~^ ,^ — ^ 03 .« c« 'k ^^ 0 0 • ^ ^ -C 0 & Oh _,,.^ -C 0 0 ,^ a ^ S a Hi P o 0 0 S 03 CD c3 0 o3 s a « 0 OJ OJ -^ c 3 c -^ 03 ►™1 r/} 36 Journal of the Mitchell Society [December Yet I am sure that these dry as dust facts cannot impress you with the wonders of insects' hfe cycles. Neither do they answer the thou- sand and one questions that you might ask in regard to this subject. In the first place we might ask why is there any metamorphosis at all? And our answer is of course an indirect one as all that we can do is to point out its all but universal occurrence among insects and to call at- tention to the fact that the groups without metamorphosis are simply a small remnant of what was perhaps a mighty race, — - a race not in the direct line of the ancestry of the higher insects but a branch from that ancient worm-like tracheated ancestor of the insects. The ad- vantages of such a metamorphosis are many. It leaves the nymph, naiad or larva, the growing period free to assimilate food and store up energy while the adult is given excellent powers of locomotion so that it may roam far and wide searching for suitable feeding grounds for the next generation. But why weary you further by recounting these thrice told tales when a few minutes spent in watching a butterfly emerge from its chrysalis or a larva change to a pupa will bring you closer to nature and impress you more with the wonders of metamorphosis than any- thing I might say. The Tax to Insects. Entomologists, especially economic entomologists, in our experi- ment stations and departments of agriculture, appreciate, in a vague way at least, the annual loss occasioned by insects but the figures are so startling and so beyond the realm of our ordinary everyday finan- cial dealings that they make little or no impression. For instance I made recently a rather careful estimate of the loss to the farmers in North Carolina last year caused by insects and was somewhat startled myself to find that it totalled no less than $84,750,000.00, as shown by the following table: Per cent. Insect Loss Damage 10 $11,050,000 20 19,425,000 10 6,875,000 10 3,500,000 20 15,500,000 5 1,000,000 20 10,000,000 5 2,400,000 5 10,000,000 5 1,000,000 10 4,000,000 $84,750,000 19£1] The Age of Insects 37 Crop 1920 Value in N. C. Corn $110,480,000 Tobacco 97,130,000 Cotton 68,750,000 Hay 35,000,000 Truck garden and crop 77,500,000 Wheat 20,000,000 Fruit 50,000,000 Forage 48,000,000 Animal and Animal Products 200,000,000 Forests 20,000,000 Stored Products 40,000,000 Enough to pay our $50,000,000 road bill and have enough left in one year to pay the ill fated $20,000,000 six year program for our institu- tions of higher education with a paltry $14,750,000 left. But I fear that most of us are not in the habit of dealing in millions of dollars and that these figures make very little impression on us. Perhaps it would be easier if we look at this as a tax. As a tax this means more than $40 for every man, woman and child in our state annually. Certainly more than the average tax for all purposes, state, city, county and town. Or let us look at it in another way. An observant entomolo- gist will tell you that in the average year our crops suffer anywhere from 5 per cent to 30 per cent depreciation from the attacks of insects. Some crops suffering much more than others. This means that our farmers pay a tax each year of from five cents to thirty cents on each dollar's worth of crop value, a tax that would not be tolerated if it were levied by any political unit, national, state or county or for any purpose be it good roads, better schools or what not. Yet this tax is levied so insidiously that we in the experiment sta- tion never hear about it and never know anything about it except by direct personal observation, save when insects destroy 75 per cent, 95 per cent or 100 per cent of the crop which happens time and time again sometimes to isolated farmers, sometimes to practically all of the farmers growing any given crop. I have frequently had tobacco far- mers tell me that the flea beetle did no damage, while at the same time we were standing in the midst of tobacco beds covering three times the area that he would have had to have under cloth if it had not been for the flea beetle. 38 Journal of the Mitchell Society [December What of the labor of preparing the soil? What of the fertilizer used? What of the extra yards of tobacco cloth that he was required to purchase? What of the fact that he was raising here a hoard of flea beetles that would follow the plants when they were transplanted to the fields and seriously check their growth when they could least af- ford to have their growth checked? What of the fact that these in- sects continued to eat holes in the leaves throughout the growing sea- son so that when the crop was placed on the market he was forced to sell at a lower price than he would otherwise have had to sell? What of the fact that careful experiments show that a flea beetle will eat more than fifty times its own weight in green tobacco every twenty four hours? Translate that into hay for an average cow or horse and think w^hat it would mean if you had to feed them from two to three tons every day. I happen to be interested in a group of insects called leaf hoppers and in their efforts on pasture lands. Does it mean any- thing that we find as high as one hundred of these tiny insects per square foot? Our mountain farmer might answer no because the chances are that he has never seen a leaf hopper but is this the correct answer? Careful experiments show that these insects actually get more from our pastures than the animals that are being pastured on them. AVith such enormous losses due to insects it might seem that en- tomologists were not keeping pace with the insects but I do not believe that this is true. A brief summary of some of the more important re- sults of economic entomology might not be amiss. When we stop to consider the tons of arsenical poisons used in this country and reflect that this whole industry was initiated by the work of entomologists we get a glimpse of the importance of this phase of entomology. In 1888 the fluted scale, w^hich had been introduced into Califoinia from Australia, had practically ruined the citrus industry. However, the Department of Agriculture sent a representative to Australia where he found that the fluted scale was kept in check by a lady beetle. This lady beetle was introduced into California and in nine months time it had so checked the ravages of the fluted scale that the scale ceased to be a menace and the citrus industry of California was saved. As you open your packages of predigested breakfast food, I wonder how many of you have noticed that they are carefully wrapped in oiled paper and I wonder how many people have tried to find the real reason for this. It is all done to control the grain weevils and was worked out by an entomologist who has by this simple means saved a great and growing industry. 1921] The Age of Insects 39 These are but a few of the many illustrations that I might have drawn from the great field of appHed entomology but they will perhaps serve to illustrate its many phases. ; Insect Friends. Entomologists lay so much stress upon the damage caused by in- sects that it is small wonder that the public is inclined to look upon insects as pests and nothing else. It was that eminent British Ento- mologist, Sir John Lubbock, I believe, who brought the opposite point of view to our attention forcibly by reminding us that he could make the world a place unfit for human habitation in less than a year's time if he had the power to remove certain insects from the world. Which is simply another way of saying that while we suffer much from the attacks of injurious insects we owe much to insects which are our friends and help to keep injurious insects in control. Entomologists are having these matters forced upon their atten- tion but apparently the general public misses the significance of the outbreaks of certain species of insects. The army worm is a case in point. Normally this insect is present every year but not in sufficient numbers to cause any appreciable loss to the farmer. Occasionally, however, the army worm becomes locally or generally abundant and causes wide spread destruction and alarm. Even a better illustration is offered by the soy bean worm. A year or two ago this insect threatened the destruction of the soy bean crop of this and adjoining states causing hundreds of thousands of dollar's worth of damage. Yet this insect is not even mentioned in standard textbooks of ento- mology and had never been a serious pest before. Why these sudden outbreaks of insect pests? The reply is that these destructive out- breaks represent what happens when the control exercised by their enemies is for any reason released. In other words it represents the condition that would prevail but for our insect friends. "The following analysis of a typical outbreak of the armj^ worm will show what usually happens. As is usual during such outbreaks, large numbers of Tachina flies were to be found in the fields laying eggs on the worms. With the intention of making a more careful study of these parasites 491 larvae were brought back and placed in cages. The following data gleaned from the records of these cages are presented as being of some interest. Of the 491 larvae, 442 were in- fested with the eggs of the dipterous parasite, leaving only 49 larvae. 40 Journal of the Mitchell Society [December or 10 per cent of the whole number, uninfested, yet 61 larvae were able to pupate. From these 61 pupae, however, only 7 adult moths emerged, showing a total mortality among the Army Worm from larva to adult of 98.6 per cent. And since 90 per cent of the larvae were in- fested with the eggs of this parasite, it would seem to indicate that, in this case at least, the parasitic fly was decidedly the most important factor in causing the high mortality of the Army Worm. In a few cases it was found that where only a single parasitic egg was attached to a larva, that the host was able to complete its transformations. "The greatest number of parasitic eggs observed on a single larva was 12, with an average of 3 for the entire number (442) infested. The 442 infested larvae yielded 709 parasitic puparia, or an average of nearly two for each infested larva. The 709 puparia yielded 556 adult parasites. The greatest number of adult flies from a single Army Worm was four. These figures show that the mortality of the parasitic fly from egg to puparium was 52 per cent, and from puparimn to adult 22 per cent, making a total mortality from egg to adult of 73 per cent. "This shows that the tendency would be for the fly to continually gain in relative numbers, owing to the lighter mortality, and easily ac- counts for the complete subjugation of the Army Worm in normal years by this one natural enemy. No other parasites were found in the course of these experiments." Since we are so dependent upon these insect friends perhaps it would not be amiss to inquire a little more closely into their life econ- omy. For convenience we may divide the friends of man into two groups, predacious insects and parasitic insects but this is merely a matter of convenience and the line separating the two is by no means a sharp one. For example we might inquire whether the larvae of the solitary wasps mentioned in another connection were parasitic or pre- dacious and while in general their behavior is that of a predacious in- sect there is little doubt that this is simply a further development of a strictly parasitic habit. Likewise the hne separating the predacious insects from the plant feeding forms is not great. Some species seem to feed predaciously if insect hosts are abundant, but if not available they turn their attention to plants. Hence we feel safe in saying that the evolution of these habits have been from plant feeding to pre- dacious insects and thence to parasitic insects. Predacious insects are many and they have varied habits. Some are active and search far and wide for their prey like the ground bee- 1921] The Age of Insects 41 ties and tiger beetles. Others are quiescent and construct traps for their prey like the ant lions. These curious fellows usually called doodle bugs construct funnel hke traps in loose sandy soil and then take up their position at the neck of the funnel and wait for a luckless ant to tumble in. The ant thus starts a miniature land slide which the ant lion aids by throwing loose sand above the ant. Some are pre- dacious only in the larval stage like the aphis lion or the aphis maggot, while others are predacious both in larval and adult condition like the lady beetles. The amount of food that these predacious insects will consume is often beyond belief. "In order to determine something of the capacity of these insects for devouring plant lice and hence their degree of economic impor- tance, I tried feeding the larvae of Syrphus americanus on cabbage aphids {Aphis hrassicae Linn.) The aphids were touched to the mouth of a larva which had not been kept from food. A four-day-old larva devoured the first aphid in 4.5 minutes, a second, third, fourth and fifth, smaller than the first, in 2, 1, 1, and 0.5 minutes, respectively. The sixth, a larger one, was retained for 3.25 minutes. These were very thoroughly eaten, all the viscera and body fluids being picked and sucked out. After this the lice tendered were not eaten so closely, but killed, a seventh in 2 minutes, an eight in 1.75 minutes, and a ninth in 1.5 minutes." An average of less than 2 minutes for each plant louse or 240 per eight hour union day. ''It is, of course, not probable that any larva would ever normally devour aphids so rapidly. Yet when plenty are at hand the number eaten by a larva during its life of eight days to two weeks or more must be very considerable. It should be kept in mind also that it is not the actual individuals eaten, alone, that determine the amount of benefit from these insects; but the fact that in this way the production of enormous number of aphids is prevented. If, as Reaumour has calculated, and others have substantiated, one aphid may be the pro- genitor of over 5,000,000,000 individuals during her existence of a month or six weeks, we can see at once the important benefit that must arise from the destruction of one or two of these aphids early in the establishment of the colony. It is a fact that the eggs of Syrphidae are often deposited on the host-plant very early or even in anticipa- tion of the arrival of the aphids." (C. L. Metcalf.) On the other hand the small amount of food on wdiich these insects seem to be able to survive is almost beyond belief. I shall never for- get a deserted wagon road below Carolina Beech where both tracks 42 Journal of the Mitchell Society [December were crowded with the funnels of the aphis Hon. These funnels aver- aged more than four to the foot in an open space about 150 feet long between a woods and a swamp. The chances of an ant traveling that road were certainly slim, but the chances of an ant lion getting very many full meals must have been correspondingly slim. Yet each one of these little fellows had moved nearly a cubic inch of earth in con- structing his funnel. As important as these predacious insects are, they are by no means as important as the parasitic insects. Allusion has been made to the Tachina fly and the army worm. In addition to these parasitic flies there is a large group of parasitic wasps which are among the most im- portant of the parasitic insects. Many of these forms are so small that very little is known about them. And I think I would be justified in saying that they are perhaps the least known of all of the insects. Yet we are gradually accumulating knowledge of these forms and some of the more important points are perhaps worth reporting here. We have among the parasitic wasps many parasites of the egg, larval and pupal stages of insects, but cases of adult parasites are not so common. Sometimes the egg of the parasite is laid in one stage but does not emerge as a perfect insect until a later stage. Usually the parasitic stage is confined to the larva which feeds upon its host while living within the appropriate stage of the host, but sometimes the parasite really lives externally as is the case with certain parasites of the gloomy scale which we have under investigation. Here the adult parasite lays her egg or eggs under the scale covering of the host. The larval parasite attaches itself to the host and sucks it dry just as a predacious aphis maggot devours a plant louse. When it has completely de- stroyed the scale it changes to a pupa and thence to an adult. The adult cuts a neat circular hole through the scale covering and makes its escape. One of the most interesting points about this parasite is the apparent ability of the female to tell the scale insects that have been parasitized. Although I have watched upwards of 150 of these parasites under the high power binocular I have yet to find a case where one has made the mistake of ovipositing upon a scale insect that is parasitized. It is exceedingly interesting to watch the business- like way that these little fellows have as they pass from scale to scale tapping each one with their antennae until they find a suitable host, then slipping the delicate ovipositor under the scale covering deposit- ing one or two or three eggs and passing on to the next victim. Among the many interesting things about these parasites not the 1921] The Age of Insects 43 least interesting is the small size of many of the forms. This is especi- ally true of some of the egg parasites which are among the smallest known insects. Imagine an insect small enough to pass all of its stages in an insect egg not much larger than the period in ordinary newspaper print and you will have a proper conception of their size. Then when you remember that each adult is furnished with a pair of eyes and a pair of antennae, three pairs of legs and two pairs of wings, with mouth parts and a digestive system, with a nervous system and sense organs and is endowed with instincts enough to feed on the nec- tar of flowers and to mate and to lay eggs in the proper host at the proper time; and all this in an insect not over }^ mm. long or so small that one hundred of them placed end to end just equal an inch; with these facts all before you you will have a proper conception of the marvelous ability of nature. I cannot pass the subject of parasitism without mentioning two special phases of insect parasitism, polyembryony and hyperparasi- tism. Polyembryony is that condition in which one egg gives rise to more than one adult individual. It is known to occur in many groups of the animal kingdom, for example, the identical twins of man and other mammals, the quadruplets of the armadillo and others. But this condition reaches its greatest development among insects where Patterson reports not less than 395 individuals from a single parasitic egg. Hyperparasitism is even more wonderful than this for here we have the case of one parasite preying upon another. We have not only the primary parasite which preys upon the host but a secondary parasite preying upon the primary parasite and a tertiary parasite upon the secondary parasite and apparently in rare cases a quarternary parasite preying upon the tertiary. Can anything more involved be imagined? And can man ever hope to unravel the intricacies of the relations that must exist in such elaborate cases of hyperparasitism? Ecological Relations. The realm of ecology is as broad as the sum total of all of the factors that touch an insect during its hfe. It is therefore not surprising that we know so little about the ecological relations of insects. The tem- perature relations are perhaps the only ones that have been investi- gated with any degree of thoroughness and here our firm ground con- sists of a series of critical high and low temperatures for a few economic 44 Journal of the Mitchell Society [December forms. These critical temperatures are of great economic importance in the control of insects of stored products and hundreds of thousands of dollars worth of furs are now held at low temperatures during the summer months thus avoiding attacks of moths. While, at the other end of the temperature scale, we find many of our largest flour mills provided with special heating apparatus so that the temperature of the mill may be raised beyond the critical point for mill insects. When it is remembered that temperature is intimately related to humidity and other factors it is perceived that the problem is an exceedingly complex one and one that will have to await better facilities for con- trolling these factors than any as yet available. Perhaps the most interesting single bit of information as yet gleaned from the many im- portant ones relative to the temperature factor is the knowledge that certain species of plant lice will withstand a much lower temperature than their parasites. Hence they are able to survive and continue to l)reed in cool weather whereas the development of the parasites is checked, thus the plant lice gains the upperhand of their parasites and do widespread damage to crops during cool weather, but if the weather is warm the parasites gain the upper hand and keep the plant lice in check. Humidity is perhaps next to temperature, the most important single factor in the ecological relations of insects. Here again we have practically an unexplored field and outside of the knowledge that many insects require a relatively high humidity for their best development, our knowledge is rather limited. The fact that air passed through certain strengths of various salt solutions and solutions of certain acids can be given almost any percentage of humidity required is of great service to the entomologist and opens up a fertile but practically un- touched field. In addition to the above problems of the ecological factors, which may be called laboratory ecology, there is another realm to which I desired to call your attention namely, field ecology. In field ecology we are not concerned with the individual factors but with the environ- ment as a whole. In other words we take our selected area as we find it in nature and try to analyze it by determining the dominant species and then determine the reasons for their dominance. The whole of economic entomology may be said to belong to the field ecology of in- sects but field ecology of insects is broader than economic entomology for it is concerned not only with economic forms but with others as well. 19£1] The Age of Insects 45 For the past few years I have been giving some attention to a prob- lem in field ecology that is very interesting to me and perhaps a statement of this problem will do more than anything else that I might say to make the whole matter clear. We have along our ocean front, our sounds, bays and rivers a narrow strip of land that is flooded twice each day by the rising tide. This strip of land may be known as the tidal zone. The part of the tidal zone lying along the ocean front where it is affected also by the direct action of the waves may be known as the strand. While that portion of the tidal zone along the sounds, rivers and bays where it is not much subjected to wave action may be known as tidal belt. While these two areas may be generically re- lated yet they are very distinct. The strand is usually devoid of vege- tation and is frequented by a group of animals that we will call beach combers. All of them are scavengers and they feed upon whatever the ocean may cast up before them. Their existence would seem to be a precarious one but when we note the abundance of beach fleas, sand scabs, ghost crabs and beach tiger beetles we are inclined to believe that nature must be very lavish with them after all. The tidal belt is far more interesting to us, however, chiefly be- cause it usually supports a luxuriant growth of sedges and grasses which in turn support a wealth of leaf hoppers and plant hoppers which are my special interest in all of the groups of insects. The ecological relations of some of these insects are most interesting. Here we have strictly terrestrial air-breathing arthropods living in an en- vironment that is strictly aquatic for longer or shorter periods twice each day. Here we have strictly terrestrial forms living in close prox- imity to strictly aquatic forms like the sea snails and fiddler crabs. Naturally we wonder why these insects have adopted this habitat. Perhaps we can explain it by stating that these insects attached them- selves to their host plant when it was a xerophyte and simply followed it into its half hydrophytic environment. This may be historically correct, but whatever is the past history of this peculiar relation Ave know that it is not simply a strict host relation at the present time but it seems rather a matter of fixity of environmental factors. This is borne out by the fact that one of the most abundant species of plant hoppers in the tidal belt region lives on no less than three species of grasses and one sedge. Another species was described originally from Long Island where it was secured from a species of the genus Spartina but on our coast where Spartina is replaced by the sea oats (Uniola) the same species of the plant hopper occurs on the Uniola and occupies 46 Journal of the Mitchell Society [Decoy^her the same situations. So much we know but there remains a vast deal more to be found out. Are these species limited in their zones by the amount of submergence that they can withstand? What are the physiological characters that make it possible for these species to sur- vive such an environment whereas their generic relatives are confined to xerophytic hal)itats? These and many other questions we might ask but only time and an unlimited amount of field work can give the answer. There is another ecological relation that it seems to me would be worth pausing to consider and that is the relation of insects to their hosts. The relation of insects to their animal hosts I have discussed in another connection under parasitism so that there is left for our con- sideration at this point the relation between insects and their plant hosts. This is a broad subject in itself and one deserving of more con- sideration than I am able to give it here. Some insects are so limited in the selection of their hosts that it is safe to identify the insect from the host on which you find it; while other insects apparently will eat anything that is green. We have in some cases whole families of insects limited to a narrow group of plants in their host relations, for example the Coleopterous family Bruchidae confines its attacks to the seeds of the Leguminosae. On the other hand we have species that are structurally closely related feeding on widely diverse plants. In fact these relations are so marked that they have been used to correct our phylogenetic notions. Thus the botanist may use insect species in determining the relationships of his plant forms and the entomologist frequently corrects his taxonomic concepts on a purely botanical basis. Naturally such relations cannot fail to impress the serious student and leave him with a vague feeling of dis- satisfaction at his failure to answer them. Thus I have puzzled mj^ mind for many hours in the hope that I might be able to answer the question, why does the gloomy scale occur on soft maples in destruc- tive numbers yet be practically absent from hard maples? Is it simply a difference in the thickness of the bark in the two groups of maples, or is it a difference in the chemical composition of the sap? Whatever the answer, the selection is remarkably clear cut because we frequently see rows of hard maples with a few soft maples inter- spersed in which the hard maples are free from scale and thrifty where- as the soft maples are dead or dying. There is another series of ecological relations that is deserving of more than passing attention. I have already referred to that com- 1921] The Age of Insects 47 plex chain reflex which causes the adult female insect to deposit her eggs so that the newly hatched young will find an abundance of food close at hand for its sustenance. These relations are easy to under- stand in those insects where the young and the adults feed upon the same host but they become increasingly difficult to understand as we pass to those adults which either do not feed or feed upon an entirely different substance. For example the adults of the order Lepidoptera, the butterflies and moths, feed on the nectar of plants for the most part yet their larvae feed upon roots, stems, leaves or seeds of plants or on animal products. The eggs must be laid in close proximity to such food or the larvae would perish and the species would vanish from the earth. What is the mechanics that brings this very desirable conclu- sion? We may answer that this series has become hereditarily in- stinctive but when we do so we are merely clothing our ignorance in a mass of verbiage. The climax in this series of complex reflexes is reached among the solitary wasps to which I have alluded in another connection. This complex may be pictured briefly and in a somewhat generalized way as follows. The female wasp digs a burrow in the soil. She goes away and searches until she finds the proper prey, be it cicada, horsefly, caterpillar or spider. She pounces upon it and stings it in the thoracic ganglia so that the prey will be paralyzed but not killed, for if the prey were killed it would decay before the egg hatched and the young larva would starve to death. She drags or carries the prey back to the bur- row, often a considerable distance, and by means of some sense that is beyond human understanding she locates the burrow and deposits her prey; lays her egg; closes the burrow and, wonder of wonders, has the time and the patience to conceal the entrance of the burrow by making it look like the surrounding territory. If in hard ground she seeks out a small pebble and pounds the loose dirt down until it blends in with the surrounding territory, or if in a tidal flat with a crust of salt she finds a bit of crust to cover the entrance. Such in brief is the story, but who has the insight to unravel the maze of ecological factors that are woven into such a complex? Another series of ecological adaptations that is so common that it causes no comment is the relation between poUination and insects. Here we are confronted with a case of parallel development that if it were not so common or if it existed only in the South Sea Islands would be one of the wonders of the age, but because we see it everywhere about us, because it is the rule rather than the exception, it arouses 48 Journal of the Mitchell Society [December no more comniont than the rising of the sun. Yet the elaborate floral devices, the presence of artfully concealed nectaries on the one hand and the presence of long tongues and pollen baskets among the insects show an evolution that must have been carried on for untold ages. And how dependent one group is on the other and any failure of the one group must necessarily mean the extinction of the other. I won- der how many such cases of sad wrecks we might find if we could re- construct the past geological ages. The highest form of interdependence is found perhaps in the case of the Yucca and the Yucca moth. "The flowers of the species of Yucca are absolutely incapable of self-or-wind-pollination, and the stigma is so situated that no ordinary insect visitor can reach it in a casual search for food. In some locali- ties, it was observed that the common Yucca never produced seed and that wherever seed was produced, almost every pod was infested by a little caterpillar that destroyed a greater or less percentage of the seeds. The parent of this caterpillar is a small Avhite moth, the Yucca moth, in which the mouth-parts are curiously modified and utterly unlike those of any other moth species that we know. At the sides of the ordinary tongue there are developed a pair of flexible processes set with little pegs and spines, and capable of being coiled like the tongue itself. When the female, which alone has these processes, is ready to lay an egg she enters a Yucca blossom, gathers a little mass of pollen, rolls it into a ball, carries it by means of the processes to the pistil, and rams it down so as to bring it into direct contact with the receptive surface. Not until this has been completed does she turn and then into the ovary or embryo seed pod, she forces an egg by means of a slender, sharp-pointed ovipositor. She is now ready to repeat the process on another flower and she does repeat it until her stock of eggs is exhausted. Here we have a deliberate pollination preceding oviposi- tion, as if the insect knew that it would be useless to lay an egg until the possibility of development in the seed pod was assured. "This peculiarity, though confined so far as we know to the genus Pronuba, is not confined to one species only. There are a number of Yuccas in the country, including the giant or tree Yuccas of the south- west, and for every species of Yucca there is a species of Pronuba. Surely a most wonderful adaptation of insect and plant, neither of which can exist without the other. "And yet, while the adaptation is not so specific, nor the evidence of design so apparent, the dependence of red clover upon long-tongued 19£1] The Age of Insects 49 bees is not less absolute. Australia has no native bumble-bee, and red clover was unknown there until the colonists began to cultivate it. There was no difficulty in making crops of forage; but it would not seed. Importing seed annually was expensive, and, naturally, the Australians were anxious to raise their own. This led to a study of the reasons for the failure, in the course of which the dependence of the plant upon bumble-bees was established. The remedy was obvious, and now European bumble-bees disport themselves among the Aus- tralian red clover, seed is plentiful, and interference with bumble-bees is a crime^ — as it should be rated everywhere. "There are many others among the Hynienoptera that are useful in the work of pollination because of their habit of feeding among the flowers, even if not on them; but all this is based on the same visits which the flower encourages and of which it takes advantage; but no account of this sort of relationship could be considered even passably complete without some reference to the complicated relationship existing between the Smyrna fig and the minute little Blastophaga, a species whose life relations have been beautifully worked out. "The Smyrna fig of commerce depends for its edible quality upon the ripened seeds that it contains. The fig is not really a true fruit as that term is generally defined, but is a thick fleshy envelope within which the flowers are contained. In the Smyrna fig these flowers are all female and no pollen is produced anywhere on the tree. Left to themselves, such trees could never produce ripe fruit, and that was the condition of the Smyrna fig orchards in California, prior to 1900. In the Mediterrenean countries, whence our commercial supply is de- rived, there are found beside the cultivated also several varieties of wild or caprifigs, which produce three crops of fruit during the season. These fruits contain male flowers, producing an abundance of pollen; but this pollen is never naturally discharged from the envelope con- taining the florets. "Yet it was recognized by the fig-growers in the Orient that to ob- tain fruit of the commercial edible varieties, it was necessary to bring to them when in bloom, branches containing fruit of the caprifig, which were usually hung up in the tree which it was intended to fructify. This work of pollination is accomplished by the Blastophaga already referred to, although, far from benefiting itself in the process, the in- sect dies without even being able to continue its kind. "In the caprifigs the female flowers are replaced by little gall-like swellings in which the larvae of the Blastophaga develop. One gene 50 Journal of the Mitchell Society [December ration of figs, the so-called 'mammae,' remain on the trees duiing the winter and by the time they are ready to drop, there is already on the trees a new or spring crop of fruit, known as the 'profichi.' By the time that this crop is in proper condition, the insects that have hiber- nated in the 'mammae,' are fully developed, the wingless and almost blind male Blastophaga has fertilized the female before she is even out of her cell, and the latter, leaving the dried-up fig by the small anterior opening, makes its way into the new figs, to provide for a new genera- tion. In the 'profichi' this generation matures at the time the com- mercial Smyrna fig is in proper condition and the females, emerging pollen covered from the 'profichi,' enter the small opening of this true female flower receptacle if they find themselves in a tree bearing them. But in this Smyrna covering all the female florets are fully developed, and the gall-like swellings that replace them in the caprifigs are absent. The insect therefore moves about over the entire interior surface of the pouch, seeking a place to oviposit, and in the process distributes its load of pollen everywhere. It eventually dies without reproducing, and usually without even being able to make its way out again. But though the insect has lost its life, the tree has gained; and the seed pouch that we know as the fig, comes to maturity and ripens seed. "At the same time that the Smyrna fig which produces the edible commercial fruit is in bloom, there is also another crop developing on the caprifigs, and these are known as 'mammoni.' The Blastophaga issuing from the 'profichi' on the same tree, naturally enter these fruits Avhich are of the same character as the preceding crops, and are able to continue their kind, coming to maturity when the third crop is ready for their reception. This third crop represents the ' mammae ' or over-wintering form, from which the 'profichi' of the following season are again entered by the Blastophaga. "Here we have an extremely complicated relationship which, re- duced to its simplest terms, means that in order to produce the com- mercial Smyrna fig there must be suitable caprifigs producing 'pro- fichi' infested by Blastophaga, at a period corresponding to the devel- opment of the female flower capsule. And as the insects are very small and very frail, the caprifigs must be either well distributed among the Smyrna trees, or the infested 'profichi' must be gathered and dis- tributed among the trees to be pollenized. "This account makes interesting reading and shows how, after many trials and much painstaking investigation, the Blastophaga and the necessary caprifigs were finally introduced into the fig-growing 1921] The Age of Insects 51 districts of California, and how a new industry, absolutely depending for its continuance upon a minute hymenopterous insect, was finally established upon a firm and scientific basis. "How many cases of this kind exist among plants having no pre- sent economic value it would be difficult to estimate, and how so com- plicated a relationship ever became established is not yet explainable even by a theory." (Smith). Fearing that I may weary you I am nevertheless impelled to point out another ecological relation that borders upon the marvelous. I refer to the relation between gall insects and their galls. We have here another case of parallelism in evolution. The galls range from simple folds of the leaf or simple enlargements of the stem to most elaborate and wonderful structures and the insects themselves are scattered in many orders. The most wonderful phase of the whole subject of galls and gall makers is the fact that the galls are absolutely specific. It is much easier to determine the gall maker by the gall that it makes than it is by the insect itself. Just what are the factors that cause any given cynipid gall, for example, to have the same form regardless of what species of oak it is found on? Just what is the stimulus that causes some galls to develop their form completely before the egg hatches? In addition to these perplexing questions we have the whole problem overlaid with the problem of parthenogenesis and alternation of hosts we can appreciate that we have here a problem that demands the best that any biologist can give. And the biologist who tackles these problems may rest assured that the field is broad enough to de- mand the best efforts that he can put forth. Conclusion Having considered briefly the past accomplishments in entomology it may be worth our while to turn our attention in another direction and ask ourselves what of the future. I do this because we are some- what prone to think that all that is good, all that is worth while lies be- hind us. Having lived through an age that has seen the development of the automobile, the telephone, the aeroplane, wireless and half a dozen other world astounding inventions we are inclined to think that all the great inventions and discoveries have been made and that there is little left to do. Which reminds me of a personal experience that will perhaps make the matter clearer than anything else that I might say. When I was a senior in high school I was told that for good and suf. 52 Journal of the ]\Iitchell Society [December ficient political reasons I could have an appointment to West Point if I could i)ass the examinations. I was persuaded not to do this by the Superintendent because, said he, "All the great wars have been fought, and you are not the type of young man that would care to hang around an army liarracks all your days." Needless to say I agree that I am hardly that type of man but I also imagine that very few of the grad- uates of West Point in the class of 1907 spent many days hanging around army barracks from April 1917 to November 1919. I remem- ber telling this story to my old teacher of Zoology and he said that lichen he told his Professor of Natural Sciences that he expected to go into Zoology his teacher tried to discourage him. "For," said he, "now that Darwin has announced his theory of Natural Selection there is nothing left for the zoologist to do." I cite these two instances because they illustrate so well an all too prevalent opinion in all fields, a feeling that is far too prevalent in a new field like entomology where the pioneers have been over the ground and harvested the first rich harvest not realizing that these same pioneers have left many corners untouched and have left abun- dant harvests yet to be garnered. That such a feeling should be still prevalent in applied entomology in the face of such enormous losses as have been pointed out above or in the face of the fact that tons of honey go to waste each year and bees are needed to gather it , is indeed hard to realize. That such a feeling should be prevalent in pure entomology when we realize how Morgan has advanced the science of genetics by breeding fruit flies, or when we consider what there is yet to learn about the anatomy, the physiology or the ecology of even our most common species is hard to understand. Except per- haps there is the notion that the pioneers had an easy time when we think that, no matter which way they turned, they were almost cer- tain to stumble into unexplored fields. While if we want to be sure that our work is not simply a repetition of something that someone else has done much better we must wade through a mass of literature often mountain high to discover nothing at the bottom. Forgetting for the time being that they had no great laboratories fitted with the finest of microscopes, microtomes, ovens, cameras and utensils of all kinds, that they had no libraries, no collections and very little apprecia- tion. While we have all of these things. Forgetting that most of the pioneers had to steal their time for research from their families or from their sleep. While all that it is necessary for us to do is to steal the time from our classes or other official duties. 1921] The Age of Insects 53 With all of these things in mind, I cannot help but feel that in spite of the past brilliant record of entomology there are better things just ahead of us. That undiscovered laws of life are awaiting the searching eye of the worker in entomology. That as yet unheard of methods of control are about to be discovered, making it possible for us to reduce the tax we pay to insects to a negligible minimum, thus making pos- sible an expansion in food production as yet undreamed. Feeling this way, I cannot help wondering if the world will be ready for these dis- coveries when they are made or will they lie buried as Mendel 's work remained forgotten for nearly half a century? Will we accept them at their true value or will we cast them aside as worthless? The Hindoos have a legend that illustrates our present tendencies very well indeed. A young man had an iron bracelet placed on his wrist one morning and was told that on a certain beach there was a stone that would turn the bracelet into gold. So he hastened out in the morning light and com- menced to pick up the pebbles one by one and touched them rapidly to the bracelet and observed the results with a critical eye. Thus he labored all through the long morning of his youth but as the sun climbed higher and higher, as the day got hotter and hotter, his speed slackened and he commenced to ask himself if it was really worth while. Wasn't the whole thing a hoax any way? Certainly no one but a fool would beheve that you could turn an iron bracelet into gold. Thus he labored through the noon-time half persuaded to stop but as the day advanced and his shadow got longer to the east and as he realized that the day was fast slipping away, he commenced to work with renewed energy that gradually changed to frenzy as the shadows of evening began to creep up from the valleys. And then as he looked down in the half light he noticed that the bracelet had indeed turned to gold. But he also realized that in his haste and in his carelessness he did not know which was the magical stone. Raleigh, N. C. THE GENUS RASPAILIA AND THE INDEPENDENT VARI- ABILITY OF DIAGNOSTIC FEATURES By H. V. Wilson The genus Raspailia (Nardo, 1833, 1847; 0. Schmidt, 1862, p. 59) was classed by Ridley and Dendy, 1887, p. 188, in the Axinellidae but transferred by Topsent, 1894, to the Ectyoninae. In this Topsent has been generally followed, including Dendy, 1895 (p. 46), who here re- gards the genus as intermediate between the two groups. Dendy later (1905, p. 172) departs from this view and regards the resemblance of Raspailia to the Axinellidae as strong but superficial. Hentschel (1912, p. 413) brings out the skeletal resemblance between the Ecty- onine genera centering round Raspailia and certain Axinellidae, and inclines to regard it as due to kinship and not to convergent evolution, thus maintaining the position of Dendy in 1895. Vosmaer, 1912, keeps Raspailia alongside of Axinella, Phakellia, Acanthella, and Phacanth- ina, thus indicating his belief in a relationship to these genera. George and Wilson, 1919, pp. 160-161, in describing Axinella acanthifera re- gard it as intermediate between typical Raspailias and Axinellas, In this species there are some acanthostyles and the dermal brushes in- clude a few long slender styles, but the habitus is lamellate, and the skeletal framework of the same type as in Axinella verrucosa (Vosmaer, 1912). In dehmiting Raspailia more precisely, Vosmaer, 1912, p. 313, takes the Mediterranean R. viminalis (O. Schmidt, 1862, p. 59) as embodying the characteristics of the genus. The characters empha- sized are : the axial skeleton is a funis (a reticular Imndle composed of elementary fibres or funiculi) with wide meshes, component funiculi thin, spicules wholly or almost wholly imbedded in spongin; from this, slender and short extra-axial funiculi (radial fibres), composed of one, two, or three spicules cemented together bj^ spongin, radiate to the surface, where each terminates in a single large style or subtylostyle, projecting far beyond the surface, surrounded at its base by a tuft of diverging small spicules, generally styles, sometimes oxea. Acantho- styles occur, dispersed in the parenchyma and echinating the funiculi. Skeletal megasclcres, chiefly long, slender styles, occasionally tylo- [54] 1921] The Genus Raspailia 55 styles and strongyles, also generally oxea. Habitus cylindrical, long and slender, branching or not branching. The long, slender, cyhndrical habitus, with skeletal framework on the general axinellid plan, and the presence of acanthostyles have been regarded by many (Ridley, Ridley and Dendy, Dendy,) as the chief distinguishing characteristics of the genus. The acanthostyles may entirely disappear but the other characteristics remain, as in subgenus Syringella Ridley (1884, p. 460). Examples are: Raspailia syringella 0. Schmidt (1868, p. 10) and the two species described by Ridley^ loc. cit. In R. [Syringella] f aid f era Topsent (1890, p. 12; 1892, p. 124) the habitus is fairly typical, and the dermal skeleton adheres to the R. viminalis type. In R. (Syringella) rhaphidophora Hentschel (1912, p. 371), the habitus is typical, save that the branches are generally com- pressed; instead of radial fibres, there are radial partitions (lamellae); dermal skeleton of the R. viminalis type; megascleres, styles, oxea, strongyles; microscleres present in shape of bundles of rhaphides. In R. (Syringella) nuda Hentschel (1911, p. 383) the habitus is typical; axial skeleton with radial fibres; dermal skeleton as in R. viminalis. All these forms make it plain that the general practice with respect to Syringella is correct and that such sponges are really members of the Raspailia group in which the acanthostyles have been lost, and should not be relegated on a technicality to the Axinellidae while Raspailia is referred to the Ectyonidae. Nevertheless Topsent (1904, p. 138) takes this position. Pick's position (1905, pp. 18-19) is different and is not opposed to the argumentation of this paper, for while assigning to the Syringella forms the dignity of a genus, he keeps the latter alongside of Raspailia. A consideration of a number of the species usually assigned to Ras- pailia makes it plain that Vosmaer 's generic concept cannot be applied in all of its details, especially in the matter of the dermal skeleton and the greatly reduced radial fibres. On the other hand the slender, elongated, cylindrical shape of body, sometimes branching, sometimes not, on which Ridley and Dendy (1887) laid chief emphasis, while common, is by no means constant. In fact, in this group of forms, as elsewhere, the characters have varied independently during the course of evolution, thus giving rise to several combinations. A generic con- cept of Raspailia, to be useful, must take into account the existence of these combinations, and cannot insist absolutely on the slender cylindrical habitus, dermal bunches of spicules such as occur in R. viminalis, monactinal character of the megascleres, or on the acantho- 56 Journal of the Mitchell Society [December styles. And yet this is what the recent definitions of the genus do, with the result that Dendy's definition (1905, p. 172) would exclude forms that are admissible on the definition of Vosmaer (loc. cit.) or of Hentschel (1911, p. 381), and vice versa. Of course the difficulty is well known. It is a difficulty offered everywhere by nature. A considerable number of species, over thirty, have been referred to this genus, A good many of them are excluded by Pick in his essay on Raspailia (1905). He would deUmit the genus somewhat more narrowly than is intended in this paper. Taking R. viminalis as a standard, some of the chief divergencies within the genus may be enumerated. It is to be regretted that in a number of the old species the data given do not permit a decision with regard to several of the features. Habitus. The long, slender, cylindrical habitus, "whip-like" in Ridley and Dendy's terminology, branching or not, is common. But it is de- parted from in a numl)er of species. For example, while the habitus is branching and subcylindrical, the branches are comparatively short and stout in several of the Dictyocylindrus (Raspailia) species de- scribed in Bowerbank's British Sponges, in R. ramosa and R. pumila e. g. In R. paradoxa Hentschel (1911, p. 381), the habitus departs widely from the typical, the sponge consisting of several somewhat flattened lobe-like divisions, which arise together from a common base and expand above. Again in R. irregularis Hentschel (1914, p. 121) the habitus deviates markedly from the typical, the sponge being club- shaped. Skeleton. The axinellid type of skeletal framework consisting of an axial column and radiating fibres may be thought of as constant in Ras- pailia. Deviations from the pi'ecise form of skeletal framework found in R. viminalis are however common among the species that have been referred to this genus. Some of them may be enumerated as follows: In R. (Syringella) clathrata Ridley (1884, p. 461) the radial fibres are thick, not reduced as in R. viminalis. In R. (Syringella) australiensis Ridley (loc. cit. p. 460) also the radial fibres are thick and project at the surface, but the surface tufts are not said to be of the R. vimi7ialis type. In R. (Syringella) rhaphidophora Hentschel (1912, p. 371), the radial fibres are represented by lamellae. In R. hifurcata Ridley (loc. cit. p. 459) a radial fibre and dermal tuft are together represented by a long style or a tuft of long styles which project at the surface (a more 19S1] The Genus Raspailia 57 reduced condition than in R. viminalis). In R. hornelli Dendy (1905, p. 172), the dermal tufts in which the radial fibres terminate include a few long styles, instead of one, surrounded by shorter ones; another deviation is made in the presence of connectives between the radial fibres. In R. irregularis Hentschel (1914, p. 121) the la^ge dermal pro- jecting spicules are in bunches and not singly as in R. viminalis. In R. flagelliformis Ridley and Dendy (1887, p. 190), the radial fibres, apparently not especially slender, terminate in projecting tufts of small spicules; habitus is typical but if we lay stress on the dermal skeleton the species must be removed to Axinella. In R. cacticutis Carter (Dendy, 1895, p. 48), there are no surface tufts of spicules, and the species would best be assigned to some other genus, as Pick (loc. cit.) has done. The R. viminalis type of dermal skeleton is known to occur in a number of species, and it may also occur in some of the older species for which the data are imperfectly given. Spicules. The skeletal spicules in the genus are smooth and in general styles, varying to tylostyles, but oxea and strongyles may occur intermingled Avith the styles {R. virninalis Schmidt, R. hifurcata Ridley, R. (Syrin- gella) rhaphidophora Hentschel). A marked deviation is afforded by R. vestigifera Dendy (1895, p. 47; assigned by Pick, loc. cit., to the closely related genus, Echinodictj^um), in which the skeletal spicules are oxea, except the small spicules of the dermal tufts which are inequi- ended and more or less stylote; in this species the radial fibres are stout, but the dermal tufts adhere in plan to the type of R. viminalis; acanthostyles are very rare and in this sense vestigial. The acanthostyles may be almost {R. vestigifera) or quite absent, the species in which this loss has occurred being grouped together as a subgenus (Syringella) . Microscleres in the form of bundles of rha- phides, may occur as in R. (Syringella) rhaphidophora; in general, absent. The facts being so, it would seem advisable to recognize Raspailia as a comprehensive, heterogeneous genus, and to include in the diagno- sis the chief lines of variation, about as follows: Raspailia Nardo Habitus often slender and cylindrical, branching or not; but the branches or unbranched stem may be comparatively short and stout, or the branches may even appear as flattened lobe-like divisions. The 58 Journal of the Mitchell Society [December skeleton is on the axinellid plan, including an axial dense aggregation of spiciilo-fibres from which radial fibres pass outward. The radial fibres may be comparatively stout, sometimes (expanded and forming lamellae, or may he reduced to one or a few spicules, or may even dis- appear as structures distinct from the dermal brushes in which they terminate. Connectives between the radial fibres generally absent, occurring only in a few species. The dermal brushes characteristically include one or a few long megascleres surrounded by numerous shorter ones, but the entire brush may be represented by one or a bunch of long megascleres, whereas in Axinella the radial fibres terminate "in tufts of diverging spicules slightly smaller than the bulk of the spi- cules" (Vosmaer). Skeletal spicules smooth and characteristically monactinal, but diactinal forms (to be looked on as variants of the type) are frequently intermingled, and in rare cases most of the spicules are diactinal. Acanthostyles characteristically occur, echi- nating the skeletal fibres and scattered, but in some species they are greatly reduced in number, in others absent (subgenus Syringella). Microscleres generally absent but may occur as bundles of rhaphides. In considering a generic concept such as that just formulated one must remember that classification is no mere mechanical assorting, a putting of like with like. That much of it is easy and delightful, but the fact that the features used in the classification of a group are or may be independent variables, that is, may occur together or some may be absent or greatly modified, makes classification more dependent on argument than is generally recognized. Often, to be sure, no argu- ment is conclusive, in the end there being several options about equally good. In such a case some consensus of opinion as to the best, most useful, practice is desirable. All this applies to the delimitation of such genera as Raspailia. One other consideration must be kept in mind in considering such generic concepts, and that is that variation may have proceeded in such a way as to make it quite impossible, in the present state of our knowledge of diagnostic points, to recognize the relationship of a given species to the genus. If, for instance, the acanthostyles are lost, a typical habitus and dermal skeleton would still show the relationship, or even the peculiar dermal skeleton might be accepted, in the absence of acanthostyles and typical habitus, as a safe index. But the dermal bunches, as we have seen, may also vary from the type, and if habitus, peculiar dermal skeleton, and acanthostyles all go, nothing remains to show the relationship. I take it that such eventualities may have 1921] ■ The Genus Raspailia 59 actually happened, since, it would seem, we must recognize as a real 1. e. natural, process the independent varying of characters. This consideration brings with it the conviction that classification in its de- tails cannot be a completely satisfactory guide to relationship. Minor uncertainties will occur everywhere. The only species of Raspailia recorded for our waters (North Amer- ica and West Indies), are the following: R. haniata O. Schmidt (1870, p. 62), West Indies. The diagnosis is very incomplete and Schmidt puts a query as to the genus. But the species, which is of typical habitus, is probably to be referred here. (R. tenuis Ridley and Dendy, 1887, p. 188, occurs off the Brazilian coast in shallow water to twenty fathoms) . R. acanthifera (George and Wilson), North Carolina coast (Fort Macon Beach). Somewhat reluctantly I conclude that this species originally referred to Axinella shoud be transferred to Raspailia, be- cause of the presence of acanthostyles and the character of the der- mal brushes, which consist of a bunch of ordinary styles together with one to a few long ones projecting far beyond the others. The species is to be regarded (cf. George and Wilson, 1919, p. 160), as a connecting link between Raspailia and Axinella. When one speaks, as in this paper, of the independent variability of structures, it is not meant to imply that any part of a body is reallj^ an independent variable. It would rather seem from all that is known concerning racial differences, that where a race has varied from the ancestral type in one feature which is conspicuous from our present view-point, it has probably come to differ from the type in a great many other features, although these may become known to us only gradually as we become intimately familiar with the race in question. It is possible and convenient to refer, as I and others have pointed out, all this kind of variation in natural races to the gene theory, since in contemporary speculation a gene is a germinal unit which, like a molecule in a radical, may influence the organism (compound) in many different directions. A good case of close correlation between specific characters in the matter of variability has been pointed out in recent years by Hent- schel (1913 a, b), who has shown that in the silicious sponge Mycale (Esperella) a large number of characters ("character values" as Hent- schel calls them, representing the concrete realizations of a schematic character, itself an abstraction drawn from a survey of the several 60 Journal of the Mitchell Society [December realizations) are co-dependent, all varying, or rather having varied in the same direction. They are, as Hentschel says, "functions of one another or of the same variable," the latter an environmental factor. We must of course suppose, since presumably we are dealing with germinal and not with somatogenic characters, that the environmental (external or internal) factor, as it increases in force, continues to modi- fy the germ in the same detail of its constitution (same gene or gene complex) and in the same direction. This brings us well into the field of speculation, but without speculation no rational experimentation. Chapel Hill, N. C. LITERATURE REFERENCES Dendy, a. 1895. Catalogue of noncalcareous sponges, etc. Part 2. Proc. Roy. Soc. Victoria, Vol. 8. 1905. Report on the sponges collected by Professor Herdman, at Ceylon, in 1902. In: Herdman Report Pearl Oyster Fisheries, Part 3. London. George, W. C. and Wilson, H. V. .1919. Sponges of Beaufort (N. C.) Harbor and Vicinity. Bull. U. S. Bureau of Fisheries, Vol. XXXVI. Hentschel, E. 1911. Die Fauna Sudwest-Australiens. Tetraxonida, 2 Teil. Fischer, Jena. 1912. Kiesel- und Hornschvvamme der Aru- und Kei-Inseln. Abhdl. Senckb. naturf. Gesellsch., Bd. XXXIV. 1913 a. Ueber einen Fall von Orthogenese bei den Spongien. Zool. Anzei- ger, Bd. XLII, Nr. 6. 1913 b. Ueber die Anwendung der funktionalen Betrachtungsweise auf die biologische Systematik. Biol. Centralbl., Bd. XXXIII, Nr. II. 1914. Monaxone Kieselschwamme und Hornschwamme d. deutschen Siid- polar-Expedition 1901-03. Reimer, Berlin. Pick, K. F. 1905. Die Gattung Raspailia. Archiv. f. Naturgesch., 71, I. Ridley, S. O. 1884. Spongiida. In: Report on the zoological collections of H. M. S Alert. British Museum. Ridley, S. O. and Dendy-, A. 1887. Report on the Monaxonida collected by H. M. S. Challenger. Schmidt, O. 1862. Die Spongien des Adriatischen Meeres. 1868. Die Spongien der Kliste von Algier. 1870. Grudziige einer Spongien-fauna des Atlant. Gebietes. TopsENT, E. 1890. Notice prelim, sur les spongiaires * * * de I'Hiron- delle. Bull, de la Societe Zoologique de France pour I'annee 1890. 1892. Contribution a I'etude des spongiaires de I'Atlantique nord. Re- sultats des campagnes scientifiques accomplies par Albert I, Prince Souverain de Monaco. Fasc. 2. 1894. Une reforme dans la classification des Halichondrina. Memoires de la Societe Zoologique de France, T. VII. 1904. Spongiaires des Azores. Resultats des campagnes scientifiques accom- plies par Albert I, Prince Souverain de Monaco. Fasc. 25. Vosmaer, G. C. J. 1912. On the distinction between the genera Axinella, Phakel- lia, Acanthella a. o. Zool. Jahrb., Suppl. XV, Bd. I. AN INTERESTING MAXIMAL CASE* By Archibald Henderson and H. G. Baity Plate 3 In lists of problems dealing with maxima and minima may com- monly be encountered the following: To find the dimensions of the rectangle of maximum area that can be inscribed in an ellipse of semi-axes a and 6. Various methods may be employed for the solution of this prob- lem; but these ordinarily suffice to veil the characteristic features of the solution, as viewed in the present paper. An enumeration of the methods usually employed will bring this into prominence. The interesting feature of the problem, under the method here stressed, is the introduction of an auxiliary curve which plays a dominant role in the solution. Method I If we represent a critical value by A and Ax by h, the customary conditions for a maximum are f (A — h) — f (a) = positive quantity f (A) — f (A + h) = positive quantity If we represent the sides of the rectangle, inscribed in the ellipse X^ y2 — + — = 1 by 2x and 2y, the area of the rectangle is given by U = 4xy. Since, from the equation of the elUpse, y = - 1 a^ — x^, a a a Let f (x) = (a^x^— x*)3^ = x(a2— x2)i^. To find the critical value, set f'(x) = 0 .' . V2 (a^xs — x^) --M (2a2x — 4x') = 0. Hence 2x {a? — 2x2) = 0; which gives x = 0, ± —-=, * This investigation, which had been directed by Dr. Henderson, was presented by Mr. Baity before the Mathematics Club, University of North Carolina. [61] (\2 Journal of the Mitchell Society [December We exclude the value x = 0, since it obviously gives the minimum lectangle, of zero area. For the present, we may omit the value X = ^from consideration — primarily because a negative length n/2 would ordinarily be excluded in seeking a positive area. We shall revert to this case, however, in the latter part of the paper. Con- fining our attention to the value + T/^rf ' ^^'^ have: f (A-h) = C^ -h'^^a^- 2 +av/~2h-hj- h2 — a 1 II h^ v/T +^^ ; +h v/2 ^2 h-- %/2 ^ - h v/2 , ., f (A) — f (A— h) = + h- + — '1- 7T + '' This is a positive quantity, since as h approaches zero, h^ remains positive, the first two terms are positive, and the remaining terms approach zero, since they all involve powers of h, and indeed h^ Proceeding in similar fashion, we derive f(A)~f(A + h) = ^_(— |. + h)^a^-|^-ax/2 h-h'-)' 1921] An Interesting Maximal Case 63 (7I-0|(;;t-0' — 2h2 -(;7T + ^)(a2x2 — x^)3^ \/a2— x2 Since A = + -^ we have s/ 2 64 Journal of the Mitchell Society [December W 2 / / a^ 2a , , \ 4ah -7=^— 211' n/ 2 ^ a? 2a , + -7= h — h^ 2 v/2 2h (a y/T — h) which is a positive quantity. Also a^ —( 2 -^ + -^ h + h2 \ V 2 ^ x/2 / a^ 2a a- — I 2 - (*") ,j-(-f **">•) n/2 ^4 h - 2h^ h^ J^_ 2a^h- \ 2 v/2 — 2h (aV 2~ + h) V(^-')' 2h2 which is a negative quantity. a £t ... Hence x = + "7^ is a critical value, which gives rise to a maximum. V 2 As before, we find for the value of the maximum area, 2ab. Method III We may deal with the function as an implicit function in the variables x and y, subject to the condition that the given point lie upon the required ellipse. 1921] An Interesting Maximal Case 65 Thus U = F(x,y) = 4xy . . . (1) subject to the condition X2 y2 The critical values for maxima and minima are to be found by dv equating to zero the first derivative of U, and replacing -p by its ClX specific value as derived from (2). Thus dU dy -— = 4y + 4x -^ = 0 from (l), dx dx and Hence 2x 2y dy = 0, from (2) dy b^x dx aV ITTT which on substitution in the equation -p- = 0, dx gives — b^x\ — r) = 0 a^y-' and therefore a2y2 = b^X^ Combining with (2), we have 2b2x2 = a2b2 giving a , , . b X = ± • ■ / — and therefore y = ± y — ■ The criterion for a maximum value is -f— „ = negative quantity, dx^ Now fi2TT dy dV dy — =4-7^ + 4x7^+4/- dx2 dx dx2 dx 66 But and Journal of the Mitchell Society [Di'xember dy ^ -b^x dx a^y dV^ -(aVy-a%lx^) ^ bx2 ^4y2 1 a%2y2 + b^X' ~ ^ a V — bHaV-) — b^ a^y' aV^ d^U — Sb^x 4b^x ) Hence dx^ aV a^y^ ' which is negative certainlj^ for the values a b Consideration of the other combinations of signs will be deferred until the last method is reached. Method IV We may deal wath the problem by expressing U as an explicit function in either x or y. Thus, solving (2) for y, we have y = + — Va- — X-, a 1921] Akt Interesting Maximal Case 67 and hence 4bx . U = 4xy = Va- — x^ a since we reject here the consideration of a negative area, a l)eing always greater than x. Let Then and f (x) = f(x) = xy/a- — x2 = (aV- — x4)M xCa'' — 2x^) _ a^ — 2x^ (a-x2 — x4)3^ ~ (a2_x2)3^ (a'' — x2)J^ (— 4x) — (a^ — 2x2). ^x f"(x) = n — ;^^ ^ (a^ — x^) _ x(2x'' — Sa") Setting f'(x) = 0, and solving we obtain a X = ± ^=- V 2 Since we have assumed that Va- — x^ is to have the positive sign, in order to reject the consideration of negative areas, we obtain, on substituting x = + — =^in f"(x/ V 2 ; a^ a^ \ 2 2 a . which proves that x = +'^^ gives a maxnnum value, as the con- dition for a maximum is that f"(A) = negative quantity. The same conclusion would have been reached had we expressed U as an exphcit function of y, and followed a similar course of reason- 68 Journal of the Mitchell Society [December ing. In that case we would have found that y = + ~~7=^ • in cither case, the final value of U would have been the same, namely 2ab. Method V By employing the parametric representation for an ellipse, we readily obtain a very elegant solution of the problem. Any point x'^ y2 on the ellipse — + -^ = 1 may be represented by X = a cos (|) y = b sin (J) when <1> is the eccentric angle of the point on the ellipse, namely the Hngle between the x - axis and the line joining the origin to the point of intersection of the line y = o sin ^ with the circle x^ +y2 = a^ W31] An Interesting Maximal Case 69 Substituting the parametric values of x and y into the equation U = 4xy, we have U = 4a cos (|). bs in 4) = 2ab sin 2(|) . . . . (1) To find the critical value of ^ for a maximum value of U, set the first derivative of U with respect to ^ equal to zero: whence Accordingly dU -T- = 4ab cos 2© = 0; dq) 2^ = 90° or 270° (|) = 45° or 135° a X = + —7=^ ; y = + Now —7- = — 8 ab sin 2 cb, dcp- giving a negative value for cj) = 45°, but a positive value for ^ = 135°. Hence ^ = 45° is the critical value for a maximum. Hence the only admissible values for giving a maximum are X = + y = + b V2' Substituting these values in (1), we have U = 4xy = 2ab, from which ab xy = — . . . (2) The form in which this result presents itself, namely that of a rectangular hyperbole xy = K, excites interest at once, and prompts a further investigation. The introduction into the problem of an apparently extraneous curve, not invoked in the original statement, suggests that this locus must play a crucial role in connection with the ellipse in the solution of the problem. a+b — a— b The co-ordinates + .— - , ,-— and ,— - , ■ ,— of two of the v 2 v 2 V 2 v 2 70 Journal of the Mitchell Society [December four corners of the niaximuiii rectangle inscribed the ellipse satisfy the equation of the rectangular hyperbola xy = ^—, Accordingly the ellipse and the rectangular hyperbola, having two points in com- mon, must either intersect each other or be tangential at the given points. The tangent to the ellipse at the point (x,, y,) has the form + a and hence we have for the tangent to the ellipse at the point .— , V 2 V2' ax by aVT ^ bVT" ^ or X y , - + Y-=V2 ■■••(3) The tangent to the rectangular hyperbola at the point (x,, yO has the form yix + xi y = ab; and hence Ave have for the tangent to the rectangular hyperbola at + a + b the point that is V2' V2 bx ay + ~~r^ = ab, \/2 VT" — + ^ = V 2 ... (4) a b As equations (3) and (4) are identical, it is clear that the ellipse and the rectangular hyperbola have a common tangent at the point + a + b ,-^ , ,— It may be noted that, since the rectangular hyperbola consists of two branches lying respectively in the first and third quadrants, the ellipse and the rectangular hyperbola cannot intersect 1921] An Interesting Maximal Case 71 each other in either quadrant, since only one corner of the maximum rectangle inscribed in the ellipse lies in either quadrant. Since the ellipse and the rectangular hyperbola have a pair of common tangents at two corners of the maximum rectangle, it is clear that the critical values may be arrived at by solving the two ab equations simultaneously. Thus substituting y = -— in the equation 2x ot the ellipse we have a*b2 b^x^ + ~ — = a-b^, or 1. e. giving 4x* — 4a2x2 + a^ = 0, (2x2 _ a2)2 = 0, a and accordingly ab 2+ -^ ^2 At this point, or at an earlier point, in the investigation, the in- quiry may be raised why both rectangular hyperbolas: ab xy = + Y and ab xy = — — ^ 2 do not enter into the problem. Although the question has virtually been answered in the course of the treatment in Method V, in the rejection of the solution <^ = — a — b 135°, it may be pointed out that while x = ~~rK-> y ~ ~~/^ formally satisfy the equation ab xy = — - 72 Journal of the Mitchell Society [December and give a rectangle of positive area, they derive from the rejected value ? = 135°. The two points + a _ — b and — a + b -^ = 7t' ^ = VT neither formally satisfy the fundamental function ab nor derive together from either 9 = 45° on ? = 135°. The association of the ellipse and the rectangular hyperbola in this problem suggests the query whether the maximum rectangle inscribed in the elUpse is at the same time the maximum rectangle which may be inscribed in the rectangular hyperbola. This question must obviously be answered in the negative, since the rectangular ab hyperbola xy = — - at once furnishes the result U = 4xy = 2ab; which shows the in variance of the rectangle area for the rectangular hyperbola, as indicated by the nomenclature. The superiority of Method V over those which precede is con- spicuous in two respects — the brevity and elegance of the treatment, and the immediate identification of the critical values which give rise to a maximum value. Chapel Hill, N. C. KEY TO THE BUTTERFLIES OF NORTH CAROLINA By C. S. Brimley (Div. of Entomology N. C. Dept. of Agr.) Butterflies may be distinguished from all other insects except the moths by the wings being covered with powdery scales which easily rub off, while from the moths they can be separated by having the antennae or feelers simple, and knobbed at tip, never hair-like, plume- like, comb-like, or even serrated. Furthermore all butterflies fly in the daytime, and most, but not all, moths at night. The following key to the families of butterflies includes only six such, all the Nymphaline families or subfamilies, except the meadow browns, being lumped together, while our single species of the Ery- cinidae, or metal marks, is included in the Lycaenidae, which group it much resembles. KEY TO THE FAMILIES OF BUTTERFLIES 1. Body stout, antennae hooked at tip (except in Ancyloxipha), species of med- ium or small size, mainly under two inches in spread of wings. Family VI. The Skippeis (Hesperidae). 1. Body slender, antennae not hooked at tip 2. 2. Front legs normal, fitted for walking, outer edge of fore wing always evenly rounded or straight 3. 2. Front legs brush-like, not fitted for walking 5. 3. Spread of wings 2>^ to 5 inches, hind wings with tail-like projections which are never thread-like. . . Family I. The Swallowtail Butterflies (Papilionidae) 3. Spread usually two inches or less 4. 4. Ground color of wings white or yellow, hind wings never tailed. Family II. The Whites and Yellows {Pieridae). 4. Ground color of wings never white or yellow, hind wings often with thread- like tails. .Family V. The Gossamer-winged Butterflies (Lycaenidae). 5. Size medium or large, colors usually bright, the prevailing shade being reddish brown Family III. The Nymphs (Nymphalidae) 5. Size medium or rather small, ground color of wings some shade of dull brown, with eye-like spots almost always present on one or both sides of one or both pairs of wings Family IV. The Meadow Browns (Agapetidae) Family I. The Swallowtails 1. Ground color light, striped with black 2. 1. Ground color black, spotted with lighter 3. [73] 74 JouRVAL OF THE MiTCHELL SojiETv [December 2. Black and white, striped Zebra Swallowtail (Papilio ajax) 2. Black and yellow, striped Tiger Swallowtail (P. glaucm turnus) 3. Underside mainly yellow, spread about 5 inches. Giant Swallowi;ail (P. thoas). East. 3. Underside mainly blat^k 4. 4. Body striped with yellow, hind wings crossed above by an uninterrupted yel- low band Palamedes Swallowtail (P. palamedes). East. 4. Body not striped with yellow, hind wings not crossed by an uninterrupted yellow band 5. 5. Underside of hind wings with two rows of yellow spots 6. 5. Underside of hind wings with one row of yellow spots 7. 6. Upper side of wings with usually two rows of light spots, inner row of yellow spots on under side of hind wings complete. . . Black Swallowtail (P. polyxenes). 6. Upper side of wings usually with only one row of light spots, fifth spot of inner row on under side of hind wings missing, and replaced by a comet like dash of scales Green-clouded Swallowtail (P. troilus) . 7. Wings glossy above, j^ellow spots on underside of hind -n-ings enclosed in a glossy band Blue Swallowtail (P. philenor). 7. Wings not glossy, upper side of hind wings with a row of blue spots, under side of wings rather faintly striped with black. Tiger Swallowtail (P. glaucus), melanistic female. Family II. The Whites and Yellows 1. Ground color of wings white 2. 1. Ground color of wings orange or yellow 6. 2. Forewings falcate, sharp pointed at tip, underside of hind wings marbled with greenish, an orange patch at tip of forewing in male. Falcate Orange-tip {Anthocaris genutia). Central Section, early spring. 2. Not as in genutia 3. 3. Forewings broadly bordered outwardly with black, albinistic females of some species of Terias and Colias. See under 6. 3. Forewings not broadly bordered with black 4. 4. Wings unmarked, hind wings not buffy beneath. Gray-veined White {Pontia oleracea). Mountains, rare. 4. Wings with some dark markings above 5. 5. Black markings on upper side of wings consisting of the tip, one or two spots on forewing and one on hind wing, these sometimes wanting in spring speci- mens, hind wings buffy beneath Cabbage Butterfly (Pontia rapae). 5. Forewings with more than two black spots, hind wings unmarked (male), or extensively marbled with dusky and white (female). Checkered White {Pontia protodice). 6. Wings aknost wholly yellow, except a row of brown spots along the outer edge in the female Cloudless Sulphur {Catopsilia eubule). 6. Wings broadly bordered outwardly with black 7. 7. With one or two pearly spots on underside of hind wings S. 7. With no pearly spots on underside of hind wings 10. 1921] Butterflies of North Carolina 75 8. Forewings coming to a sharp angle at tip, yellow on upper side of forewings bearing a rough resemblance to an animal's head. Yellow Dogface {Colias caesonia) . 8. Forewings rounded at tip 9. 9. Ground color of wings sulphur yellow. .. Clouded Sulphur {Colias philodice). 9. Ground color of wings orange Clouded Orange {Colias eurytheme) 10. Ground color of wings orange, spread over 13^ inches. Bordered Orange {Terias nicippe). 10. Ground color of wings yellow, spread under 13^ inches 11. 11. A black band across fore wings near the posterior border 12. 11. No black band across forewings 14. 12. Under side of hind wings white Banded Sulphur {Terias jucunda). East 12. Under side of hind wings rusty 13. 13. Upper side of hind wings yellow Delia Sulphur {Terian delia). East 13. Upper side of hind wings white Elathea Sulphur {T. elathea). East. 14. Under side of hind wings 3^ellow with brown spots. . Little Sulphur {Terias lisa). 14. Under side of hind wings rusty Delia Sulphur, female. Family III. The Nymphs 1. Outer edge of both fore and hind wings strongly angled or jagged 2. 1. Outer edge of hind wings evenly rounded or nearly so 6. 2. Wings dark brown with cream colored borders. Mourning Cloak {Euvanessa antiopa) . 2. Wings reddish brown, the border darker 3. 3. Silvery mark on under side of hind wings divided into a curved mark and a dot, round black spots on upper side of forewings normally six. Question-mark {Grapia interrogationis) 3. Silvery mark on under side of hindwings undivided, round black spots on upper side of forewings normally five 4. 4. Silvery mark on under side of hind wings tapered at both ends, under side of wings with grayish markings.. .Gray Comma {Grapta progne). Mountains. 4. Silvery mark on under side of hind wings expanded at both ends 5. 5. Under side of hind wings with greenish markings, wings very much jagged on the outer edges.. Green Comma Butterfly {Grapia faunus) . Mountains. 5. Under side of hind wings without greenish markings, wings only moderately jagged Comma Butterfly {Grapta comma). 6. Wings with numerous silvery spots on the underside 7. 6. Wings without silvery spots on the underside 10. 7. Forewings long and narrow, silvery spots on under side of hind wings elongate. Gulf Fritillary {Agraulis vanillae). 7. Fore wings broad, silvery spots on under side of wings round 8. 8. Spread of wings \}4 inches. . . Myrina Fritillary {Argynnis myrina). Mountains. 8. Spread of wings 2>^ to 3 inches 9. 9. Under side of hind wings with a broad yellowish band. Great Spangled Fritillary {Argynnis cybele). Mountains. 9. Under side of hind wings with a narrow yellowish band. Silver Spotted Fritillary {Argynnis aphrodite). Mountains. 70 Journal of the Mitchell Society [December 10. Ground color of upper side of wings black or blackish, usually with some white markings 11. 10. Ground color of upper side of wings some shade of brown or reddish brown. . .14. 11. Wings black, transversely banded with white, forewings long and narrow. Zebra Butterfly (Heliconin charitonia). South-east. 1 1. Wings not transversely banded with white 12. 12. Upper side of forewings crossed by a bright red band. Red Admiral {Pyratneis atalanta). 12. Upper side of forewings without red band 13. 13. Under side with numerous red spots.. . .Red-spotted Purple {Limenilis ursula). 13. Under side of wings without red spots. Diana Fritillary (Argynnis diana), female. Mountains. 14. Upper side of wings without white markings 1.5. 14. Upper side of wings with more or less white markings 19. 1.5. Spread 3 to 4 inches, inner half of wings dark, the outer half orange in strong contrast Diana Fritillary, male. 15. Spread 2>2 inches or less, colors not as in diana 16. 16. Upper side of wings with 8 to 10 rounded black spots on each wing, spread about IK inches Bellona Fritillary (Argyuuis bellona). Mountains. 16. Upper side of wings with not more than 4 or ,5 rounded black spots on each wing, if more are present on the hind wings, there are none on the forewings. 1 7. 17. Black spots as well as other markings present on upper side of forewings, color of wings mainly fuhous. Spread 2 to 2}4 inches. Variegated Fritillary {Euptoieta claudia). 17. No round black spots on upper side of forewings, spread of wings under 2 inches 18. 18. The dark color predominating on upper side of forewings. Silver Crescent {Phyciodes nycteis). Mountains. 18. The fulvous color predominating on upper side of forewings. Pearl Crescent (Phyciodes Iharos). 19. Palpi very long, snout-like; outer edge of forewing strongly angled, wings fulvous centrally, black externally. . . Beaked Butterfly {Lihythea bachmani) . 19. Palpi short as usual, outer edge of forewing not strongly angled, if at all. ... 20. 20. Wing veins all edged with black, ground color of wings reddish brown or orange 21. 21. Wing veins not edged with black 22. 21. Spread 3>^ inches or more, no black line across middle of hind wings, two rows of white spots near the outer edge of both pairs of wings. Monarch Butterfly {Danais plexippus). 21. Spread under 3K inches, a black band across middle of hind wings, one row of white dots near edge of wings Viceroy Butterfly {Limenitis archippus). 22. Wings with numerous white spots on the undersides of all wings, and at least on the upper side of the forewings also, but without any ringed eye- like spots 23 22. Wings with few white spots on any one wing, but with eye-like spots on at least the under side of the hind wings 25. 23. Spread about 3K inches, the hind wings with very few, if any white spots on the upper side The Queen (Danais herenice). Eastern Section. 1921] Butterflies of North Carolina 77 23. Spread 2 inches. Dark brown, the spots about equally numerous on all wings, above and below. ..The Baltimore (Melitaea phaeton). Mountains. 24. With one large eye-like spot on upper side of forewings, and two on the hind wings, the one on the forewings enclosed in the lower end of a whitish band, and repeated on the under side The Buckeye {Junonia coenia). 24. With no large eye-like spot on upper side of forewings 25. 25. With two large eye-like spots on under side of hind wings. Painted Beauty (Pyrameis huntera). 25. With not less than four small eye-like spots on under side of hind wings.. .26. 26. Ground color reddish brown, four or five small eye spots on under side of hind wings, spread 2J^ inches or more. . .Painted Lady {Pyrameis cardui). Local. 26. Ground color of wings dull brown, six or seven small eye spots on under side of hind wings, spread 2yi inches or less. Gray Emperor (Apatura celtis) . Central Section. Fajviily IV. The Meadow Browns (Agapetidae) 1. Forewings with a large white or yellow patch 2. L Forewings without any such patch 3. 2. Two eye-like spots in white patch on forewings, spread of wings about 2. inches Blue-eyed Grayling (Satyrus alope). Mountains. 2. Often only one eye-like spot in patch on forewings, spread about 2>^ inches. Southern Grayling (Satyrus pegala). 3. Outer border of hind wings scalloped, spread about 2 inches 4. 3. Outer border of hind wings not scalloped 5. 4. Veins of outer part of forewings of male are noticeably pale and the round black spots between them have light wedge-shaped marks on their inner side, female with only two well developed black spots on upper side of forewings Southern Pearly-wing (Debts creola). Wake county 4. Veins on forewings not pale and without wedge-shaped light spots on their inner side. Three or four well developed black spots on upper side of forewings in both sexes Pearly-wing (Debis portlandia). 5. Upper side of wings with eye spots 6. 5. Upper side of wings without eye-spots, spread less than IK inches 7. 6. Forewings with two eye-spots above, spread about 1>2 inches. Little Wood Satyr (Neonympha eurytus). 6. Forewings with a row of black spots above, spread about 2 inches. Eyed Brown (Neonympha canthus). Mountains. 7. Hind wings with a pearly or metallic patch on under side of hind wings but with no eye like spots Gemmed Brown (Neonympha gemma). 7. Hind wings with eye-like spots on under side 8. 8. Eye spots on under side of hind wings round. Carolinian Satyr (Neonympha sosybius) . 8. Eye spots on under side of hind wings elliptical. Georgian Satyr (Neonympha phocion). Family V. The Gossamer-winged Butterflies (Lycaenidae) 1. Wings reddish brown above with black spots or many fine black hues 2. 78 Journal of the Mitchell Society [December 1. Wings not spotted above with black, nor with many fine bhick Hnes on the upper side 4. 2. Wings with four or five irregular blaek lines, extending across both pairs of wings on both surfaces. Little Metal-mark {Calephelis cnenius) . Cumberland Co. 2. Wings spotted above with black 3. 3. Under side of hind wings with many small crescentic and circular fine white lines The Wanderer {Feniseca tarquinius) . 3. Under side of hind wings with small black dots. American Copper {Chrysophanus hypophleas) . 4. Wings with more or less blue on the upper side 5. 4. Wings without blue 10. .5. Hind wings evenly rounded, without thread-like tails 6. 5. Hind wings with thread-like tails 7. 6. Under side of hind wings with a row of orange crescents near the outer bor- der Scudder's Blue (Lycaena scudderi) . Mountains. 6. Under side of hind wings without any orange markings. Soring Azure {Lycaena pseudargiolus) . 7. Hind wings evenly rounded with a single thread-like tail, color of upper sur- face of wings not bordered with black Tailed Blue {Lycaena comynlas). 7. Hind wings with two tails or at least a second projection 8. 8. Blue little if at all evident on upper side of forewings, a red band on under side of wings Least Purple Hairstreak {Thccla cecrops) . 8. Blue largely present on both pairs of wings above, no red band on under side of wings 9. 9. Under side of abdomen orange, no white line on under side of wings. Great Purple Hairstreak {Thecla halesus). 9. Under side of abdomen not orange, a white line on under side of wings. White M Hairstreak {Thecla M -album). 10. Hind wings with thread-like tails 11. 10. Hind wings without tails, but often scalloped or uneven 15. 11. Under side of wings bright green, marked with brown and white. Green Hairstreak {Thecla damon). 11. Under side of wings not green 12. 12. Under side of wings with a red band near outer edge. Least Purple Hairstreak {Thecla cecrops), female. 12. Under side of wings without red band 13. 13. Under side of wings pearly gray with a single irregular white line on under side of hind wings Gray Hairstreak {Thecla melinus). 13. Under side of wings dark brown with two or more series of broken white lines or series of lines 14. 14. Outer white lines on under side of hind wings continuous. Banded Hairstreak {Thecla calanus). 14. Outer white lines on under side of hind wings broken. Edward's Hairstreak {Thecla edwardsi). Polk Co. 15. Underside of hind wings with a row of orange spots. Coral-banded Elfin {Thecla lilus). Wake and Polk Cos. 15. Under side of wings without orange spots 16. 1921] Butterflies of North Carolina 79 16. Under side of wings with numerous irregular black cross bars. Banded Elfin {Thecla niphon). 16. Under side of wings not as in niphon 17. 17. Under side of wings uniform rust red on its outer half. Brown Elfin {Thecla augustus). Polk Co. 17. Under side of hind wings with pale scales on its outer half giving it a hoary appearance 18. 18. Upper side of forewings grayish brown, under side of hind wings fairly uni- form in color Hoary Elfin {Thecla irus). Mountains. 18. Upper side of forewings reddish brown on its outer portion, under side of hind wings with a pale outer portion and a dark inner portion, these sharply defined from one another. Henry's Elfin {Thecla henrici). Polk and Wake Counties. Note. In the preceding keys no distribution is given except of those species which are apparently confined to a part of the state, the others are known to be at least fairly well distributed throughout the state. The sixth family of butterflies, the Hesperidae or Skippers, is left for another paper, the species being both numerous and hard to discriminate. Raleigh, N. C. A THEOREM OX DOUBLE POINTS IX IXVOLUTIOX By J. W. Lasley, Jr. A bilinear relation axx' +bx + cx' +d = 0 (1) between x and x', in which a, h, c, d are known, may be regarded as a projective transformation of the points .r of a line into the jioints .t' of that line. Thus 5xx' +2x + 3x' +Q = 0 (2) sends the point .r = 1 into the point .r' = — 1 and the point x = — 1 into the point x = 2. We ask ourselves can it happen that if .r = h is sent into .r' = k\ that x = kis sent into x' = h. Such transformations are said to be of period two. They are called involutions. For example xx' + 3ix +x')—7 = 0 (3) sends x = — 2 into x' = 13 and x' = 13 into x = — 2. One can convince himself that the noticeable difference between (3) and (2), namely that in (3) the coefficients of x and x' are alike, is a property which characterizes an involution. From this point of view an involution is given analytically by axx' + b(x + x') +d = 0 (4) When for x = h the relation (1) demands x' = k, k is said to cor- respond to h. Ordinarily to k will not correspond /; again. This will be so when, and only when, the projective transformation is an involution. In this event we may say that h and k correspond. The points —2 and 13 are seen to correspond in (3). Consider now the involution xx' — 7ix + x')+'S3=0 (5) different from (3). Let us see whether (3) and (5) have a common pan* of corresponding points. If so, .t and x' must satisfy both (3) and (5). We have, then, xx', — (.t + x'), 1 proportional to the two- rowed determinants obtained from the matrix 1 3 -7 1 -7 33 (6) by deleting in turn the first, second and third columns, that is xx' -.x + x' :1 = — 5:4:1 (7) Consequently x and x' are given by 0-2 — 4x — 5 = 0 (S) [80] 1921] A Theorem on Double Points in Involution 81 and are — 1 and 5. We find upon testing these in (3) and (5) that they correspond in both involutions. Let us inquire whether in an involution, like (3), there are points which correspond to themselves. If so, these are given by x2 + 6x — 7 = 0 (9) obtained from (3) by putting x = x'. These are here —7 and 1, and are called the double points of the involution. Similarly the double points of (5) are 3 and 11. The question naturally arises as to what extent a choice of cor- responding points determines an involution. Equation (4) appears to have three arbitrary constants, but it will become evident upon reflection that only the ratios of these are important. Clearly, if we knew two pairs of corresponding points, they would by (4) give us two homogeneous linear equations, which are usually just ade- quate for determining the ratios a : b \ d. For instance, let us arbi- trarily assign — 7, 1 and 3, 11 as two pairs of corresponding points, and ask for the involution determined by them. The pair — 7, 1 in (4) gives 7a+6b — d = 0 (10); the pair 3, 11 in (4) gives 33a + Ub + d = 0. (11). From (10) and (11) we have a : — b : rf as the second order determin- ants obtained from the matrix 7 6—1 33 14 1 by deleting in turn the first, second and third columns. In this way we obtain a:b:d = 1: 2: — 5. Consequently, the involution de- termined is xx' — 2{x + x') — 5 = 0 (13). whose double points are — 1 and 5. We have seen that the involutions (3) and (5) have just one pair of corresponding points in common, the pair — 1,5 given by (8). The double points of (3), namely — 7, 1 and of (5), namely 3, 11, taken as two pairs of corresponding points determined (13), and in- volution different from (3) or (5). The common pair — 1, 5 of cor- responding points in (3) and (5) turned out to be the same as the double points of (13). We shall now show that this is not an acci- dent of the particular involutions chosen, but follows from the nature of involutions. (12), 82 Journal of the Mitchell Society [December In the two involutions (4) and a'xx' + 6'(x + x') + d' = Q (14). the common pair of corresponding points are such that xx', x -\- x'' 1 are proportional to their cofactors in xx' X -\- x' 1 a h d (15), a' h' d' that is, xx' : x -{- x' : 1 = {hd' — h'd) : {a'd — ad') : {ah' — a'h). Consequently x and x' are given by {ah' — a'h) x^ + {ad' — a'd)x + {hd' — h'd) = 0 (16). The double points of (4) are given by ax'- + 2hx + d = 0 (17), those of (14) by a'x2 + 2b'x + d' = 0 (18). . The involution determined by the two pairs of points in (17) and (18) is X + x' — 2b — 26' Its double points are given by x —b —b' = 0 = 0 (19). (20), or (21) {ah' — a'6).r2 + {ad' — a'd)x + {hd' — b'd) ^ 0 which is identical with (16). We have, then, established the theorem that the common corresponding points in two involutions is the pair of double points in the involution determined by the double points of the given involutions. Chapel Hill, N. C. THE COLLYBIAS OF NORTH CAROLINA By W. C. Coker and H. C. Beardslee Plates 1 and 4-23 Cap slightly fleshy and in most species drooping soon after matur- ity, often thin, expanded or rounded at maturity; margin even, at first incurved. Gills sinuate, adnate, adnexed, or free. Stem hollow or stuffed, cartilaginous, rooting. Spores white when fresh, smooth, in most species small. Volva and veil lacking. None is known to be poisonous and all the best known larger ones are valued edibles. The Genus Collyhia will be found fairly easy to distinguish among the white spored agarics. It is a little difficult to understand at first what is meant by "cartilaginous stem," and as is usual, some species referred to this genus are not clearly typical and might easily be re- ferred to other genera. These will trouble the beginner. The largest of the genus, C. platyphylla, for example, has a thick fleshy stem and may well be looked for in Tricholoma. Collyhia confluens, C. stipitaria and C. zonata might easily be referred to Marasmius at the start and they have in fact been transferred to that genus by some authors (see Atkinson, in N. Y. State Mus. Bull. 205-206: 61. 1919). Kauffman, in his Agaricaceae of Michigan, retains them in Collyhia. The key which has been arranged has purposely been made as simple as possible, and will, it is hoped, be found practical. It covers the common species of the state, though more will probably be found as our fungous flora is better known. One species which is common in northern woods may be looked for in the mountains. It is Collyhia succosa Pk. (C. nigrescens Quel., C. atramentosa Kalch., and C.fuUgi- naria Weinm.). It will be at once recognized from the watery drops which exude from the lamellae when cut and from the black hues which the flesh assumes when injured. Collyhia tenacella (Pers.) Quel., C. ventricosa and C. clavus (L.) Quel., were reported from this state by Schweinitz or by Curtis. They are noted as doubtfully American by Murrill (N. Am. Flora 9: 374-6. 1916). Collyhia detersihilis B. & C, also reported by Curtis, is probably the same as Clitocyhe compressives Pk. It will be noted that two species have been referred to European species not before reported from America. It may be said that this [83] 84 Journal of the Mitchell Society [December has been done only after careful comparisons and correspondence with the ])est European authorities. Unless otherwise stated all numbered collections are from Chapel Hill, N. C. Important American Literature: Peck. N. Y. St. Cab. Kept. 23: 78. 1872. Bot. ed.; also N. Y. St. Mus. Kept. 49:32. 1896. Bot. ed. MuRRiLL. N. Am. Flora 9: 352. 1916 (as Gymnopus); and 9: 287. 1915 (as crinipellis) . Lloyd. Collybias of Cincinnati. Mycological Notes No. 5. Dec, 1900. Kauffman, C. H. Collybia. Mich. Geol. and Biol. Survey Publication, Bio- logical Series 5. 1918; also Agaricaceae of Michigan, p. 749. 1918. Morgan. Journ. Cincinnati Soc. Nat. Hist. 6: 70. 1883. Besides the well known works of the older mycologists see the re- cent important monograph by Sartory and Maire, Synopsis du genre Collybia, Paris, 1918. Also see Ricken, Die Blatterpilze 2: 400, pis. 106-9. 1915; Lange, Studies in the Agarics of Denmark—Ill. Dansk Bot. Ark. 2, No. 7: 10, .3 pis. 1917. KEY TO THE SPECIES Stem stout, striate, in a few cases stuffed, not velvety 1 Stem more slender, glabrous or pruinose, not distinctly striate or velvety 5 Stem distinctly velvety 11 1. Cap white or nearly so C. maculata (1) 1. Cap red or chestnut brown, or reddish ochraceous 2 1. Cap gray, grayish brown or olive 3 2. Gills pure white; stem stout and enlarging downwards C. butyracea (2) 2. Gills pure white; stem not stout and nearly equal C. dryophila (3) 2. Gills spotted with red C. distorta (7) 3. Cap viscid; stem with a long root C. radicata (8) 3. Cap not viscid 4 4. Gills blackening when injured C. semitalis (9) 4. Gills not blackening when injured C. platyphylla (10) 5. Growing on decaying fungi, small, bufify tan C. cirrata (12) 5. Growing on pine cones, small, threads at base white C. conigena (13) 5. Growing on magnolia cones, threads at base buff C. conigenoides (14) 5. Growing on thic-k beds of moss, small, brown C. clusilis (22) 5. Not growing on cones or fungi 0 6. Cap less than 12 mm. broad; plant white all over C. alba (15) 6. Cap larger; plant not pure white 7 7. Gills white or nearly so 8 7. Gills distinctly yellow C. exsculpta (11) 7. Gills buff color, no tint of lilac C. exsculpta (a form) (11a) 7. Gills brownish-lilac, or tan with tints of brownish-lilac 9 8. Growing on damp earth; plant small, the stem base with a mat of tawny PLATE 4 COLLYBIA MACULATA. No. 129S. 1921] The Collybias of North Carolina 85 hairs, color of cap dark brown C. Earleae (4) 8. Growing on earth, leaves or wood 10 9. Growing on logs; gills crowded C myriadophylla (6) 9. Growing on earth; gills not crowded and with spiny cystidia. .C. lilacina (21) 10. Usually on leaves ; cap center often rugose and always rugose on drying, color yellowish tan with center reddish; spores pip-shaped, about 3.5 - 4.5 x 6 - 9m C. nummularia (5) 10. On earth, wood or leaves; cap center smooth and usually drying smooth; color pinkish tan or yellowish brown, the center darker; spores elliptic, about 3-3.8 x 5-7/x C. dryophila (3) 11. Cap distinctly viscid C. velutipes (16) 11. Cap rough-pubescent or squamulose 12 11. Not as above 13 12. Cap gray or brov\Tiish-gray, not zonate C. siipitaria (20) 12. Cap rich tawny color, zonate C. zonata (19) 13. Cap hygrophanous C. confluens (18) 13. Cap not hygrophanous C. hariolorum (17) 1. CoUybia maculata A. & S. Plates 4 and 23 Cap up to 8.5 cm. wide, usually 4-6 cm., convex, slightly viscid, smooth, even, dull or faintly shining, not at all striate, color nearly white or a light flesh-pink with darker areas and stains of pinkish- brick color which seem to be the result of rubbing. Center usually not darker than the margin. Flesh white or slightly pinkish, 1 cm. thick in center, thinner towards margin, dense and pliable, odor de- cidedly woody, taste bitterish and distinctly astringent, sometimes tardily so. Gills colored like the cap and staining pinkish-brick on bruising; crowded, sinuate attached, narrow, 2-3.5 mm. deep, many short ones, none branched, margin eroded. Stem 5-10 cm. long usually rather deeply rooted, white, even or slightly larger at either end, tough, elastic, fibrous, with a central cyl- inder that is lightly stuffed or hollow ; surface minutely tomentose ex- cept at base where it is decidedly hairy; the hairs white or a very light cream color. Spores (of No. 1298) cream color, elhptic, 2.9-3.8 x 4.2-5 [x. Eas- ily distinguished from C. dryophila (which is nearest) by the brick- colored stains. 131. Low dense woods, Glen Burnie Farm, October 4, 1908. 594. Along branch below Howell's Spring, October 18, 1912. Spores cream color, elliptic, smooth, 3-3.7 X 4.7m. 86 Journal of the jMitchell Society [December 1298. On rotting pine log in woods south of athletic field, October ], 1914. Photo. 1884. Under pines near old iron mine, October 3, 1915. 1939. In damj) pine woods just south of athletic field, October 27, 1915. Spores smooth, subspherical, 3.6-4/^ thick. 2370. Woods near Meeting of the Waters branch, June 5, 1916. Spores 3-4 X 4.5-7m. 3011. Battle's Park just below Outdoor Theatre, April 19, 1918. 3187. Under pines by branch toward Meeting of Waters, October 5, 1918. Asheville, on or around well decayed wood in mountain woods; rather rare. Beardslee. Middle district (Schw.), woods. Curtis. 2. Collybia butyracea Bull. Plates 5, 6, and 23 Cap up to 6 cm. wide, convex, sometimes umbonate, smooth, shining, color pinkish-buff, darkest in center. Flesh 2. 5 mm. thick at stem, very thin towards margin, soft. Gills deeply depressed and angled at stem, nearly free, close, none forked, many short, up to 5.5 mm. wide near stem; white, margin strongly eroded. Stem up to 6 cm. long, usually flattened and channelled, up to 5 mm. thick at cap, enlarging downward, smooth except near base which is incrassated with white mycelium, more or less obviously marked all over with longitudinal striations, color of cap, darkest below, flesh firm, elastic, fibro-cartilaginous, quite hollow. Spores (of No. 1902) not white, exactly light buff of Ridgway, subpip-shaped, smooth, 3-3.7 x 5-6 [i.. On earth in woods, rare. There is a greasy look to the cap, which gives the plant its name. I cannot find any quality that will hold good between this and all the forms of C. dryophila. In Chapel Hill forms occur with greasy- looking caps and slender equal stems, and Beardslee 's photo, of C. dryophila on earth shows the stem enlarged below just as in C. butyra- cea. Also the slender stemmed plants of C. dryophila often show the stem distinctly lined when a lens is used. The spores of the two species as we have distinguished them here are identical. 1902. In pine and oak woods near Brockwell's, Battle's Park, October 17, 1915. 2431. Under shrubs in Mr. Woollen's yard, July 25, 1916. Spores elliptic, smooth, pointed at one end, 3-3.7 X 5.5-7.4ai. PLATE 5 COLLYBIA lU TYRACEA. No. 1902. PLATE 6 COLLYBIA BUTYRACEA. Pliolo bv B. 1921] The Collybias of North Carolina 87 Asheville, rather rare. Beardslee. Middle district, rotten trunks. Curtis. 3. Collybia dryophila Fr. Collybm siibdryophila Atk. Plates 7, S, and 23 Plants solitary, gregarious or cespitose with the enlarged bases densely crowded. Cap about 2.5-5.3 cm. broad, convex then expanded and uneven, usually a little depressed' in or around the center, smooth, hygrophan- ous; in damp weather translucent and greasy looking, in dry weather opaque and dull or faintly shining, not greasy; color pinkish-tan or dull yellowish-brown, the center darker or with a lighter *' eye. " Flesh thin, 1.5-2 mm. thick near center, soft, color of cap or whitish, taste and odor like rotten wood (fungoid), not farinaceous. Gills very thin, nearly or quite free, crowded, sinuate, the edges uneven, pure white or in age faintly creamy or pinkish-creamy; when bruised turning slowly to ochraceous. Looking at gills when fresh the color of the pileus showing through in some forms gives the effect of wine color. Stem 4-7.5 cm. long, 2-4 mm. thick, equal (typically) except for a sudden enlargement at the very base, but often varying towards the enlarged base of C. hutyracea, damp, smooth, white-tomentose near base, and with several string-like rhizomorphs; color like that of cap or lighter, pithy then hollow. If examined with a lens the stem may be seen to be distinctly striate with inherent lines of color, especially below. Spores (of No. 80) deep cream, elliptic, smooth, 3-3.7 x 4.8-7 [ji., most about 3.3 x 5.5 \i. I can find no character that will sharply separate this from C. hutyracea, and plants combining the characters of the two are often found. I am satisfied that these supposed species are forms of only one. This is the commonest and most variable of our Collybias. In old plants the pileus is often pale, and it presents many variations in size and habit. It is, however, soon learned and recognized in all its * There is a peculiar growth that has been often foimd on the cap and stem sm-face in America (not in Em-ope) that was named by Peck Tremella mycetophila. It is in the form of rather small pale globules or cusliions of various size, that are plicate and soft. They are not, how- ever, a Tremella as the basidia are club-shaped as in an agaric. Burt now thuiks it an abnor- mal growth of the Collybia itself, but Miss Hone thinks it a true parasite. See Alycological Notes No. 47, p. 662. 1917. 88 Journal of the Mitchell Society [December disguises. One photograph is of the cespitose form on old wood, ])ut it should be noted that it is often solitary or gregarious. Collyhia subdryophila was described by Dr. Atkinson from plants sent him from Chapel Hill by us. It seems to me to be one of the numerous forms of this variable species. His description is as follows (Ann. Myc. 7: 367. 1909): "Plants dry, 5-9 cm. high, pileus 2-3 cm. broad, stem 5 mm., stout. Pileus smooth, purplish or pinkish-brown. Gills white, ad- nexed. Spores oval to subglobose, granular, then usually with a small oil drop, 3-4 [jl, in diameter, rarely 5 [x, long. Stem cartilaginous, tough, hollow, equal. Belongs to Levipedes section, resembles some- what C. dryophila, but differs especially in the spores. C. U. herb.. No. 22634, mixed woods on hillside by Fern Walk near Sparrow's Pond, Chapel Hill, N. C, W. C. Coker, October 2, 1908." For good illustrations see Mycologia 3: 101, pi. 40, fig. 8, 1911, and 4: 164, pi. 68, fig. 3. 1912. 80. On side of hill east of Tenney's, October 23, 1911. 1012. Among leaves in woods in Battle's Park, October 28, 1912. Spores cream color, 3.3-3.8 X 5-7.5^. 1745. On trunk of red maple among growth of Porella, at foot of Lone Pine Hill , September 12, 1915. A depauperate form. Spores about 3.7 X "n. 2493. Gregarious to subcespitose in humus, grove at "The Rocks," May 9, 1917. Photo. Intermediate in character between C. butyracea and C. dryophila . Spores white at first, 3-3.3 X 5. 5-6. 7m, exactly like those of C. buty- racea No. 1902. 3049. Dense deciduous and also pine and deciduous woods, foot of Lone Pine Hill, May 18, 1918. Spores ovate-elliptic, white, smooth, 2.8-3.9 X 5.2-6.5M. 3066. Strowd's lowground woods, on decaying stump. May 22, 1918. 3310. On a black gum log, June 7, 1919. One plant has on it a specimen of the growth called by Peck Tremella mycocephala. Painting. 3542. Mixed woods, Battle's Park, October 28, 1919. Cap very pale buff, cen- ter slightly darker. Gills and top of stem pale yellow, darker buff be- low. Blowing Rock. Atkinson. Asheville, " In scattered colonies on old leaf mould and old wood. Often in dense clusters." Beardslee. Middle district, in woods. Curtis. 3a, CoUybia dryophila Bull. A form. We have a small, squat form of bare soil in shade that would hardly at first sight be referred to this species. It is single or cespitose; P3 Ph J?; 1921] The Collybias of North Carolina 89 the cap up to 2.5 cm., usually about 1.5 cm. broad, nearly plane or irregular, glabrous, not viscid, hygrophanous, brownish-leather color when wet, leather color or buffy leather when dry. Flesh concolorous; taste oily-woody, strong, odor same or slight. Gills rather close, sin- uate, color of cap, 1-2 mm. wide. Stem 1.5-2.4 cm. long, 1-2 mm. thick, smooth, concolorous, tough, solid, firmly attached in the soil and bringing up a ball of earth. Spores (of No. 3237) white, elliptic, 2.9-3.7 X 4.1-5.5 [i, identical with those of the typical form. 2500. In humus soil under shrubs in Arboretum, May 11, 1917. 32.37. In sparse weeds and grass under oaks, roadside home near Mebane, N. C. May 20, 1919. 3236. Bare soil, road in front of Dr. Battle's, May 15, 1919. This is just like No. 3237, except that it is abnormally squat and irregular and more cespitose; cap margin strongly recurved in most; odor and taste the same. 3240. On nearly bare soil under oak, hillside on Glen Burnie farm, May 21, 1919. Spores 3 X 4.2-5. 5m. 4. Collybia Earleae (Murrill) n. comb. Gymnopus Earleae Murrill. Plates 9 and 23 Cap 6 mm. to 3.3 cm. broad, convex, then plane or concave, smooth, dull, margin incurved until near maturity, sometimes striate; color pinkish buff or dark brown then wood brown; surface minutely puberulent all over when young. Flesh concolorous, tough; taste rankly moldy; odor faintly similar. Gills not crowded, notched at stem, narrowly adnexed, becoming practically free at full maturity, narrow, 1-3 mm. wide, pale then nearly color of cap, with tint of pink. Stem 1.5-3.3 cm. long, 1-4 mm. thick, tough and cartilaginous, hollow, granular-pulverulent, then smooth, color of cap or a darker reddish buff; attached to soil by a decided clump of tangled, tawny hairs which come up with it, bringing a ball of earth. Spores (of No. 3052) white, smooth, pip-shaped, 2.3-3 X 5.2-6 [i. This seems certainly C. Earleae, which is known only from the type locality — a creek bottom near Auburn, Alabama. The small size, dark color, growth on damp earth, pinkish-brown gills and par- ticularly the dense clump of tawny hairs easily distinguish it. 90 Journal of the Mitchell Society [December 3046. On damp ground, Strowd's lowground woods, May .5, 1918. 3052. Same locality as No. 3046, May 7, 1918. 3128. Same locality as No. 3046, May 18, 1918. Spores 3-3.8 X 5.8-7^. 3130. Same locality as No. 3046, May 22, 1918. 5. Collybia nummularia Fr. Collybia sirictipes Pk. Plates 10 and 23 This medium-sized plant grows generally in small tufts on rotting leaves in low woods. Cap up to 5.5 cm. broad, convex, then expand- ed, sometimes slightly depressed on one side, somewhat striate on margin, barely umbonate, yellowish-tan in color, often with tint of pink, the center almost brick red and usually a little rugose, often ap- pearing water-soaked. The pileus sometimes shows concentric circles near the margin, evidently due to the plants being water soaked and drying in stages. Gills close, and not very narrow, white or light flesh-colored, sin- uate-attached, or sometimes free, not quite reaching the outer edge of the cap, many short ones. Stem 3.5-7 cm. long, 3-7 mm. thick, cartilaginous, hollow, smooth, flesh-colored or whitish, darker at base, nearly equal, connected with extensive cream-colored mycelium that runs among the leaves. Spores long, pip-shaped, white, smooth, 3.7 x 7.4-8 [i, character- istically pointed and bent at the mucro end. Peck says of C. strictipes (Rep. 49: 44. 1896): "From small un- spotted forms of C. maculata this species may be distinguished by its even stem, less crowded lamellae and by the shape of its spores." From C. dryophila it is distinguished by the more yellowish cap with reddish, more or less rugose center, the more equal, paler, and more translucent stem, and by the longer, more pip-shaped spores. It is a common species and easily recognized. Kauffman has developed this species (as C. strictipes) from mycelium in leaf-mold brought into the laboratory and kept in a partially covered dish (Mich. Acad. Sci. Kept. 22: 203. 1920). 82. On leaves near Howell's Branch, October 4, 1911. 83. Among leaves, Battle's Park, October 28, 1911. 354. On rotting leaves near Howell's Branch, October 11, 1911. Spores pip- shaped, mostly pointed and slightly bent at one end, 4 X 9/l(. 584. Near Howell's Branch, October 18, 1912. Spores 3.5-4.5 X 6-9.5^. ^ w o PLATE 10 COLLYBIA NUMMI'LAIUA. No. G2S. 19^1] The Collybias of North Carolina 91 589. On leaves, below Howell's Spring, October 18, 1912. Spores 3.3-4 X 6-8.5m, with mucro end pointed and bent. 628. On leaves near Battle's Branch back of Dr. Wilson's house, October 24, 1912. Blowing Rock, Atkinson. Ashe\ille, abundant. Beardslee. 6. CoUybia myriadophylla Peck. Cap 2-5 cm. broad, thin and tough, broadly convex to plane and slightly depressed at the center, hygrophanous, brownish or grayish brown with a distinct lilac tinge when moist, paler when dry, minutely fibrillose. Gills very crowded and narrow, adnexed, brownish lilac. Stem slender, tough, 2-4 cm. long 1-2 mm. thick, colored like the cap, often compressed silky pruinose especially toward the rooting base. Spores ellipsoid, 2 x3-4 ^. Growing on old logs. Rare. This seems more common farther to the north. It is quite com- mon in the coniferous woods of upper Canada. It is very distinct in its very crowded and narrow lilac gills. The texture of the plant is suggestive of Marasmius. Asheville. Beardslee. 7. Colly bia distorta A. & S. Plate 11 Cap 2.6-8 cm. broad, campanulate, then expanded, and in age with the irregular and contorted margin upturned; glabrous, hygroph- anous, deep reddish brown, paler when dry, not viscid. Flesh toughish, pale-concolorous; taste of rotten wood; odor none. Gills crowded, up to 6 mm. wide, mostly narrower, several times branched toward the margin; edges pubescent, thick; color a dilute tan> then strongly stained and blotched with reddish brown. Stem short in ours, 2-4 cm. long, 5-10 mm. thick, often flattened; strongly channelled, inherently fibrous, the base whitish with myce- lium and connected with stout white strands which run in the rotten wood. Spores white, smooth, oval, 3.3-4.2 x 4.4-6 [i. (rather few in this collection), 3519. On a rotten log, October 26, 1919. 92 Journal of the Mitchell Society [December 8. Collybia radicata Rehl. Plates 12 and 23 Cap 3-10 cm. ])road, expanded, usually umbonate and rugose, in center sometimes nearly plane; surface viscid, glabrous, varying from pale yellowish-brown or gray to deep l)lackish-brown, the margin lighter. Flesh thin, white, toughish, taste pleasant. Gills white, rather distant, broad, adnexed to nearly free. Stem very variable in length and thickness, often most slender when longest, 5-20 cm. long above ground, 3-13 mm. thick at stem, tapering upward, and extending deeply into the earth wdth a smaller root; surface glabrous or furfuraceous, striated and often grooved, about color of cap or lighter, darkest below; texture firm, stuffed. Spores (of No. 1844) white, smooth, elliptic, 8-10.8 x 14.4-19 [l. A very variable plant both in size and color, but always easily recognized by the long rooting extension of the stem. It is common in open woods, groves and shrubby borders through the summer and fall, and is edible. Mcllvaine says it is sweet, pleasing in texture and delicately flavored. For a good illustration see Krieger in Nat. Geog. Mag. 37: 398, 1920. 130. Campus in front of Alumni Building, September 21, 1908. 372. Open place west of athletic field, October 18, 1911. 472. Steep hillside on ground and on rotting tree roots in Battle's Park, Septem- ber 30, 1912. Spores 11.8 X 15.2/x. 478. In open space back of South Building, October 2, 1912. Spores 11 X 18.5m. 495. On steep hillside around rotting tree in Battle's Park, October 4, 1912. 1844. Battle's Park, north of Piney Prospect, September 20, 1915. Asheville. Beardslee. Blowing Rock. Atkinson. Common in woods. Curtis. 9. Collybia semitalis Fr. Plates 14 and 23 Cap convex, 2.5-5.5 cm. broad, convex except for a low umbo or nearly plane, hygrophanous, not viscid, rather silky-shining, in- herently fibrous radially, at times minutely squamulose between center and margin, dark brown with a taAvny tint, the center blackish and the margin soon so on withering or touching. Flesh 1.5 mm. PLATE 12 COLLYBIA RADICATA. No. 478. 1921] The Collybias of North Carolina 93 thick near stem, pale brown, toughish, fibrous, taste and odor of raw meal. Gills crowded, 4-5 mm. wide, broadly adnate and a little decurrent, not notched; brownish drab, the margins soon darker, black when bruised. Stem 1.5-3 cm. long, 5-6 mm. thick, subequal, color and surface of the cap but rather darker; flesh concolorous, tough, firm, fibrous, stuffed and paler in center. Spores (of No. 3869) white, smooth, oval, slightly pointed at each end, 3.7-4.2 x 7.4-8.5 ^. Recognized by the rather small size; dark, smooth, inherently fibrous cap; dark, crowded, slightly decurrent gills, which change color when bruised, and by the farinaceous taste and odor. Added below is Beardslee's description of this plant from Asheville: Cap 1.5-6 cm. broad, hygrophanous, gray to deep smoky gray when moist, dingy gray to isabelline when dry, surface with darker fibrils giving it a streaked appearance, convex wdth the thinner margin incurved, then expanded and plane, flesh white, thin at the margin. Gills white, quickly becoming yellow and then black when bruised, moderately close. Stem 2-4 cm. long, 5-15 mm. thick, tough, white, changing color like the gills, stuffed but often hollow with age. Odor rancid and unpleasant. Spores usually elhpsoid, 7-9 X 5-6 [jl. Growing along paths, in bare ground in woods. This is a curious but altogether unattractive plant. I have found it only in wet weather after rains. Usually the plants are short stemmed and close to the ground, and dirty and sordid in appearance. They agree well with Bresadola's figure and description of C. semitalis to which I refer them. All my specimens agree in the quick change to yellow and then black, and all of them have the same disagreeable odor. Both of these characters are brought out in Bresadola's diagnosis. It will be remembered that Bresadola has separated his plants into three closely related species, all of which were included by Fries under the one name. The spores of the Asheville plants are typically hke those of his C. semitalis and the change of color and odor are as he describes. It is interesting, however, that some specimens had a few spores which were triangular as in his variety trigonospora, and in one plant they showed a tendency to become spindle shaped. In none was 94 Journal of the Mitchell Society [December there a change to blue, and then black. Some specimens were more like Tricholoma than Collyhia. It is hoped that more work can be done on these forms and their status definitely determined. 887. In pine and oak woods east of graded school house, October 4, 1913. Spores 3.7-4.6 X 7.4-9/1. 890. In pine and oak woods, sandy soil by edge of road, about 250 j'ards south- east of cemetery in woods, October 6, 1913. 3869. Mixed woods, back of athletic field, December 11, 1919. 3880. Mixed woods, Strowd's lowgrounds, December 13, 1919. Asheville. Beardslee. 10. CoUybia platyphylla Fr. Plates 1, 13, and 23 Cap large, up to 12.5 cm. broad, plane and regular or considerably crimped, lobed and uneven, sometimes depressed in center; surface smooth, finely punctate under a lens, not viscid, a rich bay brown (about warm sepia, Ridgway) in center,. fading to snuff brown on the margin. Flesh white, extraordinarily thin for the size of the plant, only 3 mm. thick near the cap, and fading to a mere transparent membrane near the margin. Gills deeply sinuate, barely reaching the stem at top, distant, sometimes much crumpled and ridged on faces, varying greatly in width in the same plant, some 2 cm. wide in the center, while other narrow ones running between are only a few mm. wide; color nearly white or with a slight flesh tint. Stem stout, about 5-10 cm. long, 1.5 to 2,3 cm. thick at top, some- what larger below, stuffed, then usually hollow; surface even and smooth, striate, white at top, brownish below; flesh white, firm. Spores white, smooth, oval to short-elliptic, 6.8-7.6 x 7.6-8.5 [i. Edible, but not so good as many others. 1263. In grass just east of Old West Building, campus, U. N. C, September 25, 1914. Painting. 1833. In humus, woods by branch southwest of Rocky Ridge Farm, April 20, 1915. Spores creamy in bulk, subspherical to ovate, smooth, 4. 3-5. 8 X 6.3-8m. Surface of cap brownish-gray, with whitish flecks from the cracking superficial layer. 2045. In grass near oak tree north of Alumni Building, June 9, 1916. Also occurs near stump north of President's house. 2509. In same spot as No. 2045, June 8, 1917. Oh 1921] The Collybias of North Carolina 95 3276. On a rotting oak stump in Battle's Park, June 1, 1919. A remarkable form of C. platyphylla. Cap drooping with the margin crimped inward, about 11 cm. across below, and hanging down about 10 cm., glabrous, but cracked into inherent scales over all but margined half or third. Stem very long, 24 cm., 1.7 cm. thick; fibrous, tough. Spores smooth, ovate, 5.9-6.6 X 7.7-8. l/z. Blowing Rock. Atkinson. Asheville. Beardslee. Low and middle districts, on rotten wood. Curtis. 11. Collybia exsculpta Fr. CoUyhia colorea Pk. Plate 14. Cap 2-4 cm. broad, rounded convex to broadly campanulate, with the center a Uttle prominent; hygrophanous, yellow, with the disk often reddish or brownish, minutely fibrillose; margin thin, exceeding the gills, even. Gills yellow, close; narrow, sinuate adnexed, usually turning red in drying. Stem slender, 2-4 cm. long, 3-5 mm. thick, colored like the cap, hollow, glabrous. Spores ellipsoid, 4-6 x 3-3.5 [x. On old logs; not rare. This is without question Peck's C. colorea. Our specimens have been submitted to Bresadola and approved as C. exsculpta, which is said to be rare in Europe. The gills usually change to red in drying, but I have had undoubted specimens in which this is not the case. Occasionally I have found specimens in which the growing plant were red. This, I take it, is Feck's Yav.ruhescentifolia. From the pecuhar color and its habit of growing on logs this species would be taken at first sight for Flamrnula. Asheville. Beardslee. 11a. Collybia exculpta (a form) Plates 15 and 23 Cap 1. 6-2. 6 cm. broad, convex with a depressed center, then ex- panded with depressed center, glabrous, hygrophanous, not viscid, very faintly striatulate near the margin when soaked, color about ochraceous tawny when soaked, a paler cream-lniff to chamois when 96 Journal of the Mitchell Society [December not soaked, the center at times a little darker, the thin margin soon withering to nearly black. Flesh very thin, about 0.6 mm. thick near stem, taste woody and a little bitter, odorless, concolorous. Gills crowded, color of unsoaked cap, in places becoming distinctly lilac in drying, sinuate, about 2-3 mm. wide. Stem concolorous, 2.3-3 cm. long, 1.3-3.5 mm. thick, nearly equal, base with white mycelium; mostly glabrous, a large hollow, toughish (cap rather tender). Spores (of No. 4543) white, smooth, subspherical, 3.5-4 x 3.7- 5.5 [I, no cystidia. Basidia long-clavate, about 6 \x, thick, 4-spored Hymenium about 29-33 [jl, thick. Threads of the gill trama parallel, narrow toward the margin, more swollen toward the cap. I am considering this a form of C. exsculpta, but the color is buff, not yellow or reddish-yellow and the gills are not bright suphur yellow, Also it does not grow on decaying wood but on the ground. 1735. In earth by path west of Meeting of Waters, September 10, 1915. 4543. On very rotten pine log, Strowd's lowgrounds, July 26, 1920. 4597. On rotting oak wood, swamp of Bowhn's Creek, July 30, 1920. Spores 3.7-4.5 X 4.5-7.4M. 12. CoUybia cirrata Fr. Agaricus cirratus Pers. Abs. Myc. 2: 53. 1799. Plates 1, 16, and 23 Cap 7-15 mm. broad, slightly umbonate, depressed-umbonate, or only depressed, expanded; the margin curved; glabrous, hygrophanous , not viscid, buffy tan, the margin pale, and center darker. Fles h about 0.5 mm. thick, toughish, concolorous, almost odorless, taste- less. Gills crowded, less than 1 mm. wide, linear, sUghtly notched at stem, nearly white or concolorous. Stem 0.8 -2. 5 cm. long and up to 2 mm. thick, narrowed above, or equal, about color of cap or darker, covered below with a con- spicuous dense mat of long, cottony, white or whitish, more or less radicating fibers which may extend with reduced length nearly to the top if well protected; usually only scurfy above. Spores (of No. 3491) white, smooth, oblong-ovate, 2.2-2.5 x 3.7 -4 [X. This is certainly C. cirrata, agreeing in all respects with Persoon 's original description which is as follows (translation) : PLATE 14 COLLYBIA EXSCULPTA. Photo by B. [ui)i)er left]. COLLYBIA ALBA. Photo by B. [upper right]. COLLYBIA SEMITALIS. Nos. 3869 & 3880 [below]. < fin ;?; PLATE IG COLLYBIA HARIOLORUM. Photo by B. faliovc COLLYBIA CIRRATA No. 3941 [below[. 1921] The Collybias of North Carolina 97 "Small, gregarious, cap subpapillate, plane, whitish; disk sub rufescent, gills crowded, white; stem rather long, slender, rufescent covered with long fibrillose rootlets. "Habitat. Among dead leaves in autumn, truly a parasite, es- pecially on dying Agarics. "Stems 1J4 inches long, 3^ line thick at base and sending out sparingly from the sides fibrillose rootlets sometimes 13^2 inches long, Gills narrow, even, subdecurrent. Cap about 2-3 lines broad, plane to convex, subumbilicate, 3^ line thick." Murrill thinks this the same as C. tuberosa (N. Am. Flora 9: 374. 1916) and he may very well be right. This form, however, has no tuber and the dense mat of hairs is not mentioned for C. tuberosa. Agaricus (Collybia) tuber i genus B, & C. is probably this. There is a collection from Hillsboro, N. C, in the Curtis Herbarium. It is hairy at the base like our plants and also has small tubers. It seems to be growing from earth rich in humus "under cedars. " Beardslee's notes on the Asheville plant are as follows: This species and its close relative C. tuberosa seem to need further study. True C. cirrata was found at Asheville answering well to the common description. The more common form, however, grew in masses from old decaying fungi arising in almost every case from yellowish sclerotia, but also having a dense mass of white fibrillose roots. If the presence of a sclerotium is decisive our plant is C. tuberosa. Bresadola considers this plant C. cirrata and writes that the differences are "exactly as shown in Cooke." The main difference in Cooke's figure is in the sclerotia which are deep brown or black in C. tuberosa and yellow in C. cirrata. According to this view our Asheville plants are the latter species. It seemed possible that the color of the sclerotia might depend upon their age, the yellow color being charac- teristic of the newly formed sclerotia and the dark brown or black indicating older ones. Some attempts were made to test this theory but no decisive results secured. 3491. On a dead and black, but still firm and tough, Thelephora, on earth near north branch of Meeting of the Waters, October 16, 1919. 3743. On a dead agaric in pine woods north of Meeting of Waters, November 12, 1919. Asheville. Beardslee. 98 Journal of the Mitchell Society [December 13. Collybia conigena Fr. Plates 17 and 23 Cap about 1.5-20 mm. broad, about 270 [jl thick, very nearly plane, but with a slight depression in the center, the edge turned up slightly in older specimens, surface glabrous, light brownish-tan, or the center pinkish, minutely pubescent. Threads of flesh very irregular and knotty. Gills almost white with a brownish tinge, nearly or quite free, some branched, quite narrow toward the margin. Threads of gill flesh 3.7 \x thick. Stem about 2.5-5 cm. long, very pale, lighter in color than the cap or gills, minutely pubescent (velvety) at maturity above and with long white hairs at the base which attach it to the cone. These threads are very long and conspicuous rhizomorphs that look like stiff cotton threads and are very peculiar. They may extend from as much as the lower third of the stem. Spores (of No. 3503) white, extremely minute, oblong, about 1.5-2 X 3-4 [x. Basidiaabout 3.7 [JL thick and 13 [i long. Cystidia only on margin of gills, 6.6-9.3 [j. at thickest part, about 15-25 ^ long. Easily recognized from its habit of growth on pine cones. While C. esculenta and C. conigena are said by Bresadola to have much larger spores, this is not borne out by the more recent European monographs. Lange (1. c. p. 18), Ricken (1. c. p. 414), and Sartory and Maire (1. c. p. 176) all describe the spores to be substantially as in our American plants. Their creeping stems which are hairy on the rooting portion could not separate our plants. It is only in the spores that a marked difference appears. Collybia esculenta is listed by Schweinitz from this state. For comparison of this and C. conigenoides, see the latter species. 84. On pine cone, October 20, 1911. 2948. On cone of Pinus echinata, October 1.5, 1917. 3503. On decaying pine cones, October 25, 1919. Asheville. Beardslee. Low district, rotting pine cones. Curtis. 14. Collybia conigenoides Ellis. Plates 18 and 23 Cap 3-15 mm. broad, convex then nearly plane, at times depressed in center, striatulate, very finely pubescent, a little viscid, buff in center, paler toward margin; the cap surface composed of large swollen cells through which project the short hairs which are about PLATE 17 COLLYBIA C0NIGP:NA. No. 3503. PLATE 18 COLLYBIA CX)NIGEX0IDE8. No. 3545. 1921] The Collybias of North Carolina 99 6-7.5 [J. thick at ])ase and of variable length up to 55 [i. Flesh less than 0.5 mm. thick, nearly tasteless and odorless, toughish; threads of flesh about 3.7 ;j, thick. Gills white or palely concolorous, rather close, ventricose, 1.5 mm. wide in center, rounded at stem and slightly adnexed, not veined or branched. Stem 1.5-4 cm. long, 0.5-0.9 mm. thick, finely puberulent all over like the cap, except in the basal region which is covered for some distance by long, woven, fine buff hairs which bind the stems together; color a clear ochraceous buff all over except for the abruptly whitish tip; tough, hollow. Spores minute, smooth, elhptic, pointed at one end, 2.2-2.9 x 5-6.3 [J. . Basidia 4-spored, about 4.4 [jl thick and 18 \x long. Cystidia present, contracted above the swollen body. Mostly cespitose, but some single. It approaches very closely to Marasmius, reviving quite well in water. This is certainly C. conigenoides, every character agreeing with the original description (Bull. T. B. C. 6: 76. 1876). We have examined a collection determined by Ellis and distributed as No. 3503 in Ellis and Everhart North American Fungi on cone of Magnolia Fraseri from Nuttallburg, W. Va. (Herb. Dept. Agr., Washington). Although in bad condition this specimen is without doubt the same as ours, with the long buff hairs conspicuous around the stem. The species is different from our plant on pine cones which we are calling C. conigena. The latter has smaller spores and basidia, gills branched in part, a paler stem, with white, not buff threads below, and no bladder-like cells on the cap surface. The plant from Michigan on pine cones referred by Kauffman to C. conigenoides cannot be our species on magnolia cones as the former has a white stem with white hairs at the base and shorter spores. 3545. By path in Arboretum on fallen magnolia cones, October 28, 1919. Photo. 15. Collybia alba Pk. Plate. 14 Cap 6.5-11 mm. broad, rounded-convex, white, glabrous. Stem 1.7-2.6 cm. long, 2 mm. thick, pure white, glabrous. Gills broad, ventricose, nearly free. Spores 4-5 X 3 ^J- Growing on old mossy logs and stumps. This small white species 100 Journal of the Mitchell Society [December is found frequently in the summer, and has been referred to Peck's species with which it seems to agree. The dried plants become dingy as they dry, as noted by Peck. Asheville. Beardslee. 16. CoUybia velutipes (Curt.) Fr. Plates 19 and 23 Plants densely crow^led and imbricated or somewhat scattered, growing on logs. Cap up to 4.5 cm. broad, very irregular in shape and surface, ridged and often deeply pitted, general outline rounded or nearly plane; surface very glutinous and viscid, smooth, color a strong dull red (about burnt sienna) in center, shading out to a yellowish-red on margin; in old wet plants a deeper blackish-red. Flesh light reddish- yellow (about color of gills), about 3 mm. thick near stem, quickly thinning to less than 1 mm., tasteless or sweetish. Gills moderately close, sinuate attached, with a broad, deep tooth near stem, about 8 mm. wide at the tooth and 4 mm. wide beyond; color a light reddish-yellowy about pale yellow-orange of Ridgw^ay, lighter when young. Stem central or somewhat lateral, al^out 2. 5 to 5 cm. long, usually strongly flattened at top or to full extent, about 5 to 8 mm. wide at cap, tapering downwards, and usually fused with others at base into a dense clump, surface densely short-tomentose, almost velvety; color of gills at top, dark reddish-brown elsewhere, texture tough, almost cartilaginous at surface, more fibrous inside; solid or partly hollow. Spores (of No. 1507) white, very abundant, elliptic, smooth, 3.4 x 5.1-8.5 [x. This is one of the good edible mushrooms and it may be had often in any of the winter months. We find it in Chapel Hill only in cool weather. For an elaborate account of the plant with ten plates see Stewart in Bull. No. 448, N. Y. Ag. Exp. Sta., Geneva, Feb. 19 18; also Biffen in Journ. Linn. Soc. 34: 147. 1899. For other illustrations see Mycologia 1: 39, pi 3. 1909; Krieger. Nat. Geog, Mag. 37: 398. 1920. 1507. On end of hickory log in grove behind Memorial Hall, December 9, 1914. 2013. On a charred oak stump, southwest of athletic field, December 18, 1915. Spores elliptic, smooth, 3.2-4 X 5.5-8m. < 0^ n P-, 1921] The Collybias of North Carolina 101 Asheville. Beardslee. Middle and upper districts, on rotting logs. Curtis. 17. Colly bia hariolorum Fr. Plate 16 Cap 2-5 cm. broad, broadly campanulate, becoming expanded, and at length nearly plane with the center a little prominent, pale tan or pale rufescent at first, becoming white with age, glabrous, striate on the margin when moist; flesh white, thin, especially on the margin; odor when crushed strong and unpleasant. Taste disagreeable. Gills white, narrow, closely crowded, adnate with a distinct sinus. Stem 2-4 cm. long, 2-4 mm. thick, hollow, slightly enlarged at the base, everywhere covered with white villous down, which is longer and more marked at the base, the extreme base usually curved and attached by an abundant white mycelium to the leaves in which it grows. Spores 4-6 x 2.5-3 [jl. Somewhat gregarious, on old leaves in woods. This species appeared quite frequently in late summer at Asheville. It is suggestive of C. confluens, and may easily be taken for it. As found at Asheville it is more nearly white than C. confluens, has a shorter stem, and is not inclined to occur in the dense clusters which are characteristic of C. confluens. The rather disagreeable odor is also a mark of distinction. Asheville. Beardslee. 18. Collybia confluens Fr. Marasmius confluens in N. Am. Flora 9: 269. 1915. Plates 20 and 23 Cap 1.3-4.6 cm. broad, convex then expanded, the center broadly compressed, the margin curved and striatulate when moist; hygrophanous, reddish-brown and viscid when wet, leather color when dry. Flesh toughish, concolorous, about 1 mm. thick in center; taste and odor slight. Gills moderately close, up to 4 mm. broad, rounded at stem and adnexed, color of dry cap. Stem 4-6 cm. long, finely white pubescent above, the threads longer and more cottony below and often binding several together, 102 Journal of the Mitchell Society [December color of cap when sho-\vii through the pubescence; tough, often com- pressed ; hollow. Spores white, smooth, elliptic, pointed, 2.5-3.7 x 6.2-7.4 \x. 3533. Mixed woods back of cemetery, October 26, 1919. Blowing Rock. Atkinson. Asheville. Beardslee. Middle and upper districts, among rotten leaves. Curtis. 19. Colly bia zonata Pk. Plates 21 and 23 Cap up to 3. 6 cm. broad, convex, or nearly flat with a broad umbo, a sharp depression in the center (umbilicate) at all ages, flatly hemi- spheric when young, with the margin strongly incurved ; surface con- spicuously clothed with roughish hairs of a rich tawny color, the hairs usually pinched into groups and flattened. Flesh thin, tough, white, taste sweetish, of a disagreeable, fishy nature, odor strong and of the same nature, and persisting long after drying. Occasionally the odor is absent, as in No. 2658. Gills white, rather close, narrow, about 1.5 mm. wide, quicVly rounded at the stem and barely reaching it at the upper angle. Stem slender, even, up to 5 cm. long, about 1.5 to 2 mm. thick, tough and strong, with a small irregular hollow about the size of a needle; surface covered with similar hairs as the cap and of the same color. Spores white, elliptic, smooth, 4.5-5.4 x 6.4-7.2 [jl. The plants are cespitose from decaying bits of twigs, etc., on the ground and are remarkable for their penetrating odor, somewhat re- sembling the fishy smell around old wharves, only more acid. This is not mentioned by others. Not found at Asheville by Beardslee and apparently new to the state. For a discussion of this and related species see Atkinson N. Y. State Mus. Bull. 205-206: 61. 1919. For other illustration see Mycologia 4: pi. 56, fig. 8. 1912. 1577. From twigs, rootlets, old beech fruits, etc., on ground. New Hope Swamp' June 26, 1915. 1899. On a rotten root, woods at foot of Lone Pine Hill, October 17, 1915. 2241. On hull of Hicoria ovata, swamp of New Hope Creek, June 24, 1916. 2568. By path in woods along Battle's branch, July 2, 1917. PLATE 20 COLLYBIA CONFLUENS. No. 3533. ^. o 1931] The Collybias of North Carolina 103 2658. On rotten oak log, low damp woods by Battle's branch, July 12, 1917. The characteristic odor of the type was absent when fresh, but was slightly noticeable when dry. Taste faint, but unmistakably that of type. Other plants with very strong characteristic taste and odor were grow- ing on the same log with this, but several feet away. 3112. New Hope Swamp on decaying bark, June 23, 1918. 20. Collybia stipitaria Fr. Marasmius stipitarius (Fr.) Atk. and House. Agaricus scahellus Alb. and Schw. Plate 23 Cap 5-12 mm. broad, convex, depressed a little around the center which is itself concave, roughly fibrous, that is, the inherent fibers forming irregular elevated ridges and near the margm pinched into squamules, pale tan to gray or brownish-gray, the center (in No. 3370) abruptly a much deeper gray-brown; texture of cap and stem tough and persistent; taste and odor none. Gills rather distant, about 1 mm. broad, abruptly sinuate at the stem and nearly or quite free, pale-creamy white, the margins toothed. Stem 2-5 cm. long, 0.5-1 cm. thick, equal, spongy-scurfy all over, inserted, i. e. disappearing into the substratum and not aris- ing from superficial mycelium; about color of cap center, the tip shad- ing to tawny. Spores smooth, oval to elliptic, 5.1-6.2 x 8.9-10.4 [i. Cystidia acute to mucronate, simple. Easily recognized by the fibrous-squamulose cap, dark center, nearly free gills and spongy stem surface. It is distinguished from C. zonata, which is near, by the smaller size, absence of fishy smell and longer spores. For discussion of this and related species see Atkinson in Bull. N. Y. St. Mus. 205-206: 61. 1919. Massee gives measure- ments of C. stipitaria as: cap 4-11 mm. across and stem 1-2 in. long. For other illustration see Lloyd, Mycological Notes 1, No. 5: 42, fig. 15, 1900. 3370. On herbaceous debris, grove in front of Gimghoul Lodge, June 26, 1919. Asheville. Beardslee. Middle and upper districts, on decaying trunks. Curtis. 104 Journal of the Mitchell Society [December 21. Collybia lilacina n. sp. Plates 1, 22, and 23 Solitary or gregarious and at times subcespitose, rather often with Uttle undeveloped ones attached to the stem bases of mature ones. Cap up to 7.5 cm. usually about 4-5.5 cm. wide, hygrophanous, de- cidedly or very slightly umbonate, somewhat uneven, expanded, margin striatulate when moist, even or nearly so when dry, flat or bent down; surface smooth, like fine leather in appearance, the mar- ginal third often rugose in youth, the wrinkles disappearing; color tan with the center decidedly deeper and usually with a tint of lilac at maturity. Flesh thin, only 1. 8 mm. thick at stem, whitish except at center, which is brownish-lilac, tough, almost tasteless. Gills rather distant, variable in attachment just as in Clitocyhe compressipes, sometimes deeply sinuate, most of them barely attached and not at all decurrent, again squarely adnate in part and sinuate in part and some slightly decurrent by a tooth, very easily separating from the stem when attached, about 5-8.5 mm. wide, broadest near stem, color a pallid tan or bright tan, then darker with brownish-lilac tints and smoky on drying, many short, none branched. The surface of. the gills is set with spiny cystidia which project about 20-25 [i. Stem very variable in length even in plants of the same size, up to 11 cm. long and 6.5 mm. thick at cap, nearly equal, usually twisting in drying and becoming lined from top to bottom, tough and semi- cartilaginous, firm, elastic; surface pruinose and often lined above, smooth below, the very base enlarged and tomentose with the fine white mycelium; color of cap, lilac tinted at maturity especially above white at base; flesh strongly brownish-lilac, deepest colored within, a large hollow cylinder in center from top to bottom. Spores (of No. 1818) white, elliptic, smooth, 5.2 x 7.8 \i. Very young plants are nearly black, but soon become paler. The lilac tints do not appear until maturity and deepen afterwards. This change is peculiar and constant. Smaller specimens of the species have very much the general appearance of Marasmius oreades, but differ in the smooth hollow stem, tendency to lilac tints in all parts at and after maturity, in not reviving well when moistened and in the much larger size attained at times. The habit also is different, our plants being solitary or sparsely gregarious, and growing in woods and shrubl^ery and on bare earth, not in open grassy places. It also PLATE 22 >v COLLYBIA LILACINA. No. 3288. Photo of dmwins, to show size. 1921] The Collybias of North Carolina 105 seems near C. nigrodiscus Pk. I am inclined to think this is the plant listed by Curtis as M. plancus, Fr,, which has a similar habit and size and has a hollow stem, but M. plancus differs in its narrower gills and downy stem, and in absence of lilac tints. In size, shape, and thick- ness of flesh, Mycena Zamurcfisis Pat. and Gail, from Venezuela (Bull. Soc. Myc. Fr. 3: pi. 8. 1887) recalls our plant, but is excluded by the absence of lilac tints and differently shaped spores. I have looked through the Curtis herbarium under Marasmius and Collyhia but could find nothing like this. 1752. In damp shaded spot in soil among weeds and grass, woods at foot of Lone Pine Hill, September 12, 1915. 1818. One plant. On dry shaded path in Arboretum, northeast side, September 17, 1915. Stem eccentric; gills almost triangular, wide in center, pointed at stem and just reaching it, distant, veined at cap, rather light brown- ish-drab with a tint of lilac. Stem granular-pruinose above, smooth elsewhere, tough, 2.5 cm. long, hollow; cap 3.5 cm. wide. 2193. Woods below rock wall, south of Peabody building, June 21, 1916. Cap about 3 cm. broad, strongly convex, umbonate, smooth, appearing slightly tomentose under a lens, hygrophanous, fleshy-buff color, darker in center; margin thin, even, becoming brownish-lilac. Spores white, smooth, elliptic, pointed at one end, 3.7-4.4 X 5.5-8ix. 2810. Among shrubs near wall, east side of Arboretum. 3288. Under Magnolia in Arboretum, June 4, 1919. 3290. Under Magnolia soulangeana in Arboretum, June 4, 1919. Fine plants, up to 6.5 cm. in diameter. Painting. 4331. Under shrubs in Arboretum, June 24, 1920. Spores variable, smooth, el- liptic, 4-5.5 X 6-9m. 22. Collybia clusilis Fr. (sense of Schroeter) Mycena palustris (Pk.) Sacc. Cap up to 1 cm. broad, very smooth, convex, not umbonate or umbilicate, brownish-olive or buffy-brown (Ridgway), paler when young, very thin and delicate but not striate. Gills pale yellowish-brown, distant, slightly decurrent, not sinuate, less than 1 mm. wide, only about 20 to 25 in number and a few short ones. Stem slender, about 3 cm. long, color of gills, smooth, hollow, extending deeply into the moss and there covered with mycelial strands. Spores white, subspherical to eUiptic, smooth, 3.5-6 x 4-9 [i. This very pretty little plant seems to be confined to thick beds of moss. 106 Journal of the Mitchell Society [December Notes by Bcardslee follow: Cap 0.5 cm. to 2 cm. broad, rounded convex, at times slightly raised ' at the center, becoming more expanded with age and somewhat de- pressed, hygrophanous, pale brown or brownish-olive, paler when dry, and becoming opaque, and with a slight silky luster, margin thin, striatulate when moist, even when dry; flesh thin. Stem slender, Aveak, 3-6 cm. long, a little lighter in color than the cap, attached by abundant white mycelium to the mosses in which the plant grows, smooth, and hollow. Gills grayish brown, rather distant, adnate, rather narrow, venous connected. Spores elliptic, 7-9 by 4-5 [x. Odorless when fresh, but developing a slight disagreeable odor. Growing in beds of sphagnum. This interesting plant was found in abundance in Sweden in 1905. I have since seen it in similar places in Maine. When first found it could not be determined with certainty, though its abundance in one of Fries' collecting grounds indicated that it could not have escaped him, especially as it is more than usually striking. Lange's excellent notes on Collybia made it possible to identify it as above. Schroeter has an excellent description as Lange points out in Pilze Schlesiens, page 642, which exactly fits our plant. Fries' description does not fit as well. Cooke's figure is not a good representation of our plant. Ricken's description presents some difficulties. There seems little doubt that our plant is C. clusilis in the sense of Lange and Schroeter. As it occurred in Sweden good opportunities for studying it were given. Successive crops of specimens appeared after rains in the same moss patches and its variations could be observed. The shape of the cap seemed to vary considerably. What seemed to be the typical form uniformly showed a slight umbo, or papilla. Other plants were rounded or even depressed at the center, though scarcely so as to be called umbilicate. The type material of Mycena palustris (Pk.) Sacc. has been carefully compared with our specimens and found to be iden- tical, though the description seems to indicate a discrepancy in regard to the gills. 1532. In a thick, dense bed of a large moss (Dicranum scoparium), woods south of cemetery, December 4, 1913. It has also appeared in a similar bed of the same moss near the sphagnum bed east of athletic field. Chapel Hill, N. C. Perry, Ohio. PLATE 23 OO C?. 1921] The Collybi^s of North Carolina ' 107 Explanation of Plate 23. CoUybia maculata. No. 594. Fig. 1. Collybia butyracea. No. 1902. Fig. 2. CoUybia dryophila. No. 3049. Fig. 3. CoUybia Earleae. No. 3052. Fig. 4. CoUybia nummularia. No. 584. Fig. 5. CoUybia radicata. No. 372. Fig. 6. CoUybia semitalis. No. 3869. Fig. 7. CoUybia platyphiUa. No. 3276. Fig. 8. CoUybia exsculpta. No. 4543. Fig. 9. CoUybia cirrata. No. 3491. Fig. 10. CoUybia conigena No. 3503. Fig. 11, spores; fig. 12, hair on cap; fig. 13, cystidia on gill margin; fig. 14, basidium. CoUybia conigenoides. No. 3545. Fig. 15, basidium and cystidium; fig. 16, hairs and swollen cells on cap surface; fig. 17, spores. CoUybia velulipes. No. 2013. Fig. 18. CoUybia confluens. No. 3533. Fig. 19. CoUybia zonata. No. 1577. Fig. 20. CoUybia stipitaria. No. 3370. Fig. 21. CoUybia lilacina. No. 3290. Fig. 22. Figs. 12-16 X 670; others X 2160. ABSTRACTS AND REVIEWS Effect of the Relative Length of Day and Night and Other Factors of the Environment on Growth and Re- production IN Plants. By W. W. Garner and H. A. AUard. (Note: The authors have furnished by request the following ab- stract of their work. Mr. AUard was assistant in Botany in the Uni- versity of North Carolina in 1904-05. Both authors are now in the Department of Agriculture, Washington. Their paper under the above title was published in Journ. Agr. Research 18, No. 11, 1920.) Although the intensity of the light and the quality as regards wave- length of radiation are recognized as important factors in the develop- ment of plants, the present paper deals mainly with the behavior of the plant in response to the daily duration of the period of light. This phase of the subject of light effects upon plants appears to have re- ceived little attention in the past but in the present paper sufficient evidence has been accumulated to show that it has an extremely im- portant bearing on the expression of plants as regards growth, stature, and specialization in the direction of sexual reproduction. The main feature of the present paper is a demonstration of the fact that with many plants, sexual reproduction in some manner is a function of the relative length of the day and night. In other words, by artificially shortening the summer daily illumination period by keeping certain plants in a dark house for suitable periods of the day, sexual reproduction or flowering is initiated. Thus, the plants may be made to bloom at will, weeks or months in advance of controls responding to the normal seasonal length of day. Thus, certain late varieties of soy beans, namely Biloxi and Tokio, in particular, and the variety of tobacco known as Maryland Mammoth, have shown them- selves very responsive to such conditions. The wild aster, Aster linariifolius, and other species also blossomed precociously, so to speak, when the length of day was reduced to 12 hours or 7 hours, re- spectively. Plants of this class may be considered short day plants, since sexual reproduction has been initiated by a length of day con- siderably shorter than the normal summer day which tends to promote vegetative growth, until the shorter days of late summer and autumn intervene to initiate flower and seed production. On the other hand, certain plants have consistently shown a dif- ferent behavior, and have failed to bloom in response to a day length of 7 hours, as obtained by the use of the dark house. Climbing Hemp [108] 1921] Abstracts and Reviews 109 weed (Mikania scandens), wild Hibiscus {Hibiscus Moscheutos) and the common garden variety of radish (Scarlet Globe) are members of this class. For the sake of convenience these plants have been termed long day plants, indicating that they attain sexual reproduction suc- cessfully when the days are relatively long. By the use of electric light of low intensity to increase the relatively short duration of illumination of the winter days, results in line with those obtained when the summer day has been shortened, were secured. Thus, soy beans and cosmos blossomed weeks and months after the controls enjoying the normal duration of illumination of the winter days. It is evident that the duration of the daily illumination in itself is of primary significance in controlling the course of development to- ward or away from the flowering stage or sexual reproduction. Experiments with several so-called late varieties of soy beans in the field, planted at intervals from April to August, have shown that the shortening of the period from planting till the first appearance of blossoms, is dependent upon the seasonal length of day to which the successive plantings have been subjected. In the light of these results it is believed that the natural distribu- tion of plants is governed more or less directly by the seasonal length of day which obtains for the different latitudes of the earth from the equator to the poles. From the evidence at hand it will be seen that the stature and season of flowering of certain plants is dependent upon a favorable length of day, and this may actually be a most important limiting fac- tor in determining crop yields in many instances. In other words, the time for propitious seeding to obtain maximum yields may be governed very largely by the length of day to wdiich the crop will be exposed. Since it has been shown that certain plants respond wdth a definite behavior to certain day lengths, the term "photoperiodism" is sug- gested to designate this response. Teaching of Geometry. By Archibald Henderson, Professor of Pure Mathematics, University of North Carolina. If this paper (a pamphlet of 49 pages, Univ. N. C. Extension Series No. 33) simply followed the usual treatment of books on "The Teach- ing of Geometry," it would not call for special mention; but, as it strikes a distinct note, and gives many fresh discussions not found 110 Journal of the Mitchell Society [December in our geometries, it seems appropriate to call attention to it as an original work of high scientific value that should prove not only help- ful, but stimulating to teachers and students in geometry. In the Introduction, Dr. Henderson properly calls attention to the lessons of the world war as to the prime necessity of Mathematics relative to the scientific progress, welfare and preservation of a nation, which naturally recalls the saying of Napoleon that, "The advance- ment, the perfecting of mathematics, are bound up with the pros- perity of the state." In discussing "The Aims and Results of Geometrical Study," the author emphasizes the fact that the true purpose of instruction in geometry is to develop the faculty of independent thinking in geome- try, to acquire facility in working problems — "originals, "as they are happily called — -in other words, to train the student as an investigator — a research worker. There can be no question as to the correctness of this point of view. Students so trained, take an increasing interest in the study — they "make good — ■" whereas, those neglecting this discipline, soon lose their mental self-reliance and intellectual courage to tackle new problems and difficulties, become discouraged, resort to mere memorizing, and thus, ultimately fail. The author next takes up "The Problem of Instruction," and ad- vocates the natural method of instruction, even when it is longer than the usual synthetic method. The usual text-books, following almost exclusively the synthetic method, are models of "Compression, ele- gance and rigor;" but they, too often, leave the student puzzled as to what the author is driving at, until the end is reached; when, presto, a conclusion is reached which comes as a distinct surprise to the reader, who has not been prepared for the denouement l)y being given the reasons for the successive steps of the demonstration. By the synthetical method, whether for the demonstration of theorems or the solution of problems, we start from known theorems or problems and endeavor to effect a solution; but, as it is often dif- ficult to know from what known theorems or problems to start, a series of fruitless essays may be made before hitting upon the proper solu- tion. On the contrary, by the natural method — that of the "old an- alysis" of Plato — we have the advantage of a starting point, the thing to be proved; and from that, an endeavor is made, by logical processes, to reach a known result. When this is attained, then if the successive 1921] Abstracts and Reviews 111 results are reciprocal, or each can be obtained from the one that fol- lows, the theorems or problem posited in the beginning is true; since it can be proved by the synthetical method, by reversing the steps and working from the first conclusion or known results.* The method of analysis is generally that of research and discovery; and because of its importance to the investigator and because of the slight attention accorded it in existing texts, Dr. Henderson has, pur- posely, given a number of illustrations of its working in solutions of theorems and problems. In fact, the treatment by the analytical method of problems and theorems is one distinctive feature of the paper, which should appeal particularly to the eager student who aims at any research in geometry. "The Basic Problems of Construction" are treated by the author in an interesting manner. Most of the constructions are simple; some are complex, and are given as stimulating problems, since one object of the paper is to give new and instructive points of view. This is especially noted in the section entitled "The Problem of Research," where the various modes of approach to the solution of geometrical problems are indicated, and numbers of illustrations are given with a completeness and elegance of demonstration that causes one to regard this section as the most interesting part of the essay. The scope of this section can be judged from the following sub- headings: 1. The Method of Analysis, 2. The Method of Successive Substitutions, 3. The Method of Reductis Ad Absurdum, 4. The Method of Intersection of Loci, 5. The Method of Construction of Loci by Points, 6. The Method of Transformation; Construction of Auxihary Figures, 7. The Method of Parallel Translation, 8. The Method of Rotation Sjonmetry, 9. The Algebraic Method, 10. The Method of Similarity. The final sections on "Procedure in Attacking Geometrical Prob- lems" and a Biographical Note complete the subject. The paper is illustrated with 26 figures, and is written in the at- tractive style one has come to associate with the author. It is plain- ly intended for teachers and research workers, for the author is a firm * See Duhausel's "Des IMethodes dans les Science de Raisonnement," vols. 1 and 2; also, Cain's "Symbolic Algebra and Notes on Geometry" (D. Van Nostrand Co., New York) for a full discussion of the analytic method, including the cases of "lost" solutions and of those "strange" to the questions. 112 Journal of the Mitchell Society [December believer in that method of instruction which constantly calls for the working of "originals", and this brochure should prove especially help- ful and inspiring to both teacher and student in pursuing this plan. Wm. Cain The following three abstracts were pubhshed in the University of North Carolina Record No. 179, Graduate School Series No. 2, August 1920. In Regard to Species and Sponges. By H. V. Wilson. The Scien- tific Monthly, October, 1919. A comparative study of sponge species indicates that hereditary characters are independently subject to variation such that in respect to any one of them individuals and races occur which form close series between far distant extremes. Such series are doubtless in many cases phylogenetic ones in which the terms bear to one another the re- lation of ancestral species and descendant. In other cases it would seem that the terms of the series represent only different degrees in the environmental stimuli which related protoplasms have made inde- pendently of one another. It is recognized that the gene theory which assumes the existence in the germ cell of minute units, representative of the hereditary char- acters, is applicable to the facts stated above, as well as to the facts of Mendelian inheritance in particular, if only we assume enough units in the germ cell. In thus extending the theory to cover all forms of heritable differences between organisms, it may be questioned whether it retains any practical (pragmatic) value. Nevertheless it would seem that symbolism of this sort does contribute to precision of think- ing, if it be recognized for what it is, viz., conceptual symbohsm. It is called to mind that many today would remove the gene from the conceptual world and give it a perceptible body, that is, they would identify it with a chromatin granule. The known facts however do not necessitate, according to some even contradict, this view as to the nature of chromatin and chromosomes. Sponges ofBeaufort(N.C.) Harbor AND Vicinity. By W. C. George and H. V. Wilson. Bulletin U. S. Bureau of Fisheries, XXXVI, Document 876. 1919. (Body of the paper accepted as a thesis for the Ph. D. degree awarded to W. C. George, 1918). The paper includes a description of sponges present and in any de- 1931] Abstracts and Reviews ,113 gree conspicuous in the Beaufort area. Seventeen species are de- scribed, most of them new. Of these the "Fishing Bank," a bank of coralline nature with a West Indian fauna, to seaward of Beaufort In- let, has yielded four. Collecting on the sea-beaches was incidental, most material so collected being unfit for precise study. The bulk of the sponges are harbor forms, at least eight sufficiently abundant to be available for investigations of an experimental nature. The occur- rence of a minute horny sponge of very simple character, designated Pleraplysilla latens, is noteworthy, both because horny sponges as a group inhabit more southern waters and because of the morphological simplicity of the form. The families, subfamilies, and genera represented are defined, and the paper may thus be used for purposes of identification. A con- siderable amount of comparative data falling under the general head of variation is recorded, and in the case of a number of the genera there is discussion of the facts on which they rest. The illustrations, of en- tire sponges and microscopic preparations, are for the most part photo- graphic. Asymmetrical Regulation in Anuran Embryos with Spina bifida Defect. By H. V. Wilson and Blackwell Markham. Journal Ex- perimental Zoology, XXX. 1920. (Body of the paper accepted as a thesis for the M. A. degree awarded to Blackwell Markham, 1918.) Abnormal embryos and larvae of the frog and toad are described, the developmental processes in which add to our knowledge of what is called the regulatory power of organisms. This is the power which enables an organism, lower adult or embryo of higher form, to restore or develop the typical form of body, after the destruction or amputa- tion of a part of the whole, or after some interference in development which blocks the normal course of differentiation. In the particular cases described the normal backward growth of the axial structures of the embryonic body, such as notochord and spinal cord, is prevented. In a well-known type of embryo of this sort the tissue of the blastopore lips, two stripes which diverge from the posterior end of the embryonic body, becomes organized, each stripe forming a half spinal cord, half notochord, etc., the half structures gradually coming together (process of 'concrescence') in the median line to form a complete spinal cord, complete notochord, etc. But in the embryos here described a dif- ferent and asymmetrical kind of regulation is employed. Instead of both streaks (blastopore lips) organizing and fusing, only one streak 1 14 Journal of the Mitchell Society [December organizes. It organizes however in such a way as to prockice not a half but the whole, that is, both right and left halves of the trunk of the body. Thus the end result, the production of a typical form, may be reached by very different paths. This variety in the fundamental formative processes of which an embryo is capable makes it impossible to think of development as at bottom a deterministic process, viz., as one in which the embryo is a machine composed of (self-propagative) parts each the material cause and origin of a particular portion of the body. Back numbers of the Journal of the Elisha Mitchell Scientific Society- can be supplied as follows: AT $0.50 PER PART Vol. 4, pt. 1 Vol. 5, pt. 1 Vol. 6, pt. 1 Vol. 7, pts. 1 & 2 Vol. 10, pts. 1 & 2 Vol. 11, pts. 1 & 2 Vol. 12, pt. 1 Vol. 13, pts. 1 & 2 Vol. 14, pts. 1 & 2 Vol. 15, pt. 2 Vol. 16, pts. 1 & 2 Vol. 17, pts. 1 & 2 Vol. 18, pt. 2 Vol. 19, pts. 1 & 2 Vol. 20, pts. 1,3, & 4 AT $2.00 PER VOLUME Vols. 21-32 inclusive AT $3.00 PER VOLUME Vols. 33 to present time DOUBLE NUMBER VOL. XXXVII MARCH, 1922 Nos. 3 & 4 JOURNAL OF THE Elisha Mitchell Scientific Society CONTENTS Isotopes. Francis P. Vcnahle 115 Some Considerations in Defense of the General Biology Course. /. P. Givlcr 123 Notes on the Oecology and Life-History of the Texas Horned Lizard, Piirynosoma Cornutum. J. P. Givler. . , . 130 A Magnetite-Marble Ore at Lansing, N. C, W. 8. Bayley .... 138 A Botanical Bonanza in Tuscaloosa County, Alabama. Roland M. Harper 153 Fishes in Relation to INIosquito Control. Samuel F. Hildchrand 161 Notes on the Morphology and Systematic Relationship of Sclerotium Rolfsii Sacc. B. B. Biggins 167 An Interesting Anomaly in the Pulmonary Veins of Man. W. C. George -. 173 The Eastern Shrubby Species of Robinia. W. W. Ashe 175 A New Oak from the Gulf States. W. D. Sterrett 178 A New Genus of "Water Mold Related to Blastocladia. W. C. Coker and F. A. Grant 180 Forest Types of the Appalachians and White Mountains. W. W. Ashe 183 Index to Volumes 32-37 200 issued quarterly CHAPEL HILL, N. C, U. S. A. ENTERED AT THE POSTOFFICE AS SECOND-CLASS MATTER The Elisha Mitchell Scientific Society W. deB. MacNIDER, President. W. F. PROUTY, Vice-President. J. M. BELL, H. R. TOTTEN, Permanent Secretary. Recording Secretary. Editors of the Journal: W. C. COKER, Chairman. J. M. BELL COLLIER COBB Journal op the Elisha Mitchell Scientific Society — Quarterly. Price $3.00 per year; double uumbers, $1.50. Numbers for sale are listed inside the back cover. Direct all correspondence to the Permanent Sec- retary, at the University of North Carolina, Chapel Hill, N. C. In addition to original papers on scientific subjects this Journal pub- lishes the Proceedings of the Elisha Mitchell Scientific Society, and the Proceedings of the North Carolina Academy of Science, as well as abstracts of papers on scientific subjects published elsewhere by members of the Fac- ulty of the University of North Carolina. PUBLISHED rOE THE SOCIETY B .' THE UNIVERSITY OF NORTH CAROLINA JOURNAL ^"..^ ..tu« Elisha Mitchell Scientific Society Volume XXXVII MARCH Nos. 3 and 4 ISOTOPES By Francis P. Venable The fundamental conception in chemistry is that of the atom. The atomic theory is the basis of all explanations offered as to the consti- tution of matter and such reactions and other chans'es as may occur in matter. The atom is possessed of certain characteristics or proper- ties that distinguish it. It has even been sugo'ested that an atom is a bundle of properties. The mass or weio-ht of the atom has been as- sumed to be an unvarying;- property and hence to be classed as a con- stant of nature. The determination of one of these constants, which after all means an attempt at measurino' the attraction exerted by other masses of matter upon it, is of course relative in its results and beset by many difficulties and chances for error. At first the methods used were too crude and the results obtained too inaccurate to .iustifj^ any conclu- sions as to the unvarying nature of these so-called constants, but with the improvements in apparatus, methods, and manipulation there was reached a degree of confidence which caused some investigators to question the constancj^ of the atomic weights. Schiitzenberger, Bout- lerow, and others raised this question but no satisfactory conclusion could be reached so long as the possibility of error in such determi- nations was unavoidable. There was, however, a persistent suspicion that changes in the atomic weights might occur in the course of chemi- cal reactions. To refute this we have the well-known experiment of Landolt which proved that within the limits of experimental accuracy no change in the sum of the total interacting weights of matter can be detected when chemical action takes place. For the usual routine work of the chemist, then, it can be taken for granted that the weight [115] 116 Journal of the Mitchell Society [March of the atom is an invariable or constant quantity. It is to be noted however, that the proof is not absolute, and furthermore that while the sum total weig'ht might have been found to be the same the pos- sibility of change in single atoms was not excluded. As explanatory of some of his results Crookes, in his classical in- vestigation of the rare earths, threw out the suggestion that in the course of reactions, and such have taken place throughout untold periods of time, changes might be wrought in certain of the atoms under the stresses to which they had been subjected. These he called ''worn atoms." If this were so, then the determinations, in which vast numbers of atoms are dealt with, could give only the average of all atoms concerned as the weight of one. It is manifest that chemical methods alone could not give a satisfactory answer to such a question as this, but after nearly half a century- the same conclusion has been practically reached through the use of modern methods, largely phy- sical. It would seem that in a number of eases at least our accepted atomic weights represent an average weight only. The announcement of the Periodic System by Mendeleeff induced a renewed and increased interest in the atomic weights and their de- termination. This sj'stem showed that when the elements were ar- ranged in an ascending series according to the increase in their atomic weights they fell into certain periods and groupings which brought out remarkable relations as to chemical and physical properties. By means of this system Mendeleeff was enabled to predict the existence of certain elements at that time unknown, and to give a fairly accurate description of them and their properties. These predictions were, for the most part, confirmed soon afterwards and the system took its place in science as a natural system. It is important to note, however, that in drawing up his ascending series Mendeleeff relied more upon the properties of the elements than upon the atomic weights. His boldness in pointing out places to be filled by yet undiscovered elements testifies to this, and still more the fact that in certain cases where there was conflict between the phys- ical properties and the atomic weight in deciding the position or an element in the series he unhesitatingly adopted the properties as the deciding factor so that so far as these elements are concerned it is not a strictly ascending series of atomic weights. This transposition was quite allowable at a time when most of the atomic weights had been only inadequately investigated. In the cases where this liberty was 1922] Isotopes 117 taken the atomic weights fell very close together and it was within reason to think that the probable error lay there. The two chief in- stances were those of Te and I; Co and Ni. During the following years many determinations were made to settle this discrepancy. The differences between them were under one-half of a unit but they were real and persistent. Some suggested the existence of companion ele- ments which could not be separated. Indeed Kriiss announced the discovery and separation of such a companion element with nickel which, if removed, would leave the atomic weight of nickel greater than that of cobalt and thus justify Mendeleeff in so placing it in the series. Kriiss died shortly afterwards and his supposed discovery has never been confirmed. The proof that Mendeleeff was right in placing these elements as he did was finally brought about through the reve- lations of radioactivity. This much was evident from the first, how- ever, namely, that each element had its definite position in a series, or place in a system not artificially arranged but forming a natural order. In this orderly arrangement two factors decide the position of the element. These are the mass and the electrical content. That the elements were electrically charged was recognized by Davy within a few years after the announcement of the atomic theory. The clear exposition of the inter-relationship of the elements and their arrangement in a definite order practically placed their com- posite nature beyond question and their genesis became a subject of speculation. Of course Prout had been the first to enter this field, but so far as he was concerned it was a sheer guess without foundation in fact or logic and should never have received the attention given it. So, too, the later hypotheses lacked fundamental data, though some of the guesses were shrewdly near the developments of these latter years. Wliile it was definitely settled that each known element had its definite place in the series, no especial import was placed upon the relative number of this position. This is now known as the atomic number and can be determined accurately by physical means. It was first accomplished by radioactive methods but Moseley's marvelous application of the defining power of quartz crystal to the definition of the x-rays emitted by each element under a bombardment by nega- tive elections has superseded all other methods. The spectra so ob- tained reveal an orderly shifting of certain groups of lines. Begin- ning with any one element, the position of all others in the series can 118 Journal of the Mitchell Society [March be determined. In other words, the atomic number of any element can be found in this way. Radioactivity has solved the constitution of the atom. Ruther- ford's disintegration theory and his demonstration of the building up of the helium atom have finally settled that problem. "We now know that the atom is built up of positive and negative electricity — according to Rutherford's conception, a positive nucleus of alpha par- ticles surrounded by a field of negative electrons. The discussion of this or other atomic models is apart from the object of this paper. The Periodic System represented the place occupied by an element in the series as primarily a function of its mass, but in reality mass is secondary and the electrical content is the chief factor. As already stated there are two variables in the structure of each atom — mass and electrical content. The former decides the position of the element in the vertical columns of the Periodic Table and the latter decides the position in the horizontal columns. In consequence of the influence of the electrical content, Soddy reasons that a chemical element is not necessarily homogeneous and its atomic weight may be, and possibly is generally, a mean value rather than a natural constant. The fact that some elements are known to be radio-active — that is, with some of their atoms undergoing disintegration — that even such elements as potassium and rubidium are sul)ject to a slow disintegration of their atoms which involves the formation of atoms of lesser mass, brings the thought near that possibly all elements are subject to the same process of change except that the rate is too slow to admit of detection by such instrumentalities as have hitherto been used. Quite recently the statement has been made that by means of a new device it has been found possible to detect and register the expulsion of one alpha par- ticle from zinc in every nine and a half hours. So far as I know, this has not been confirmed. But enough is definitely known to bring us back to the worn atoms of Crookes. The addition of some thirty or forty new elements known as radio- active elements but having valid claims to recognition as real elements puts too severe a strain upon the Periodic Table as conceived and con- structed. This is far in excess of the number of A^aeant places, espe- cially when one reflects that the rare earths which have been shifted from place to place are still dissatisfied with their accommodations. Making use of the two variables named above, it was found that a few of these radioactive elements — as, for instance, radium emanation. 1922] Isotopes 119 which belongs to the group of the monatomic gases — found lodgment in some of these vacant places; but the great majority fall in places already occupied by well-known elements. Thus seven fall in the place occupied by lead. This necessitates the use of the same atomic number for eight elements. These radioactive elements possess identical chem- ical characteristics with lead and can not be separated by chemical means. The minute amount of the radioactive elements available ren- ders a comparison of the spectra difficult. In a number of cases they are known to be identical and according to Soddy's theory should be, but certain generalizations (as that of Hicks) are opposed to this view. The name isotope was adopted by Soddy to designate these ele- ments. The word means same place. Thus RaG is an isotope of lead ; RaC is an isotope of bismuth. No strictly chemical means for separat- ing these elements is known. In the same way ionium and thorium are isotopes and there are three other isotopes in that place in the Periodic System. As these isotopes have different phj'sical properties, they can be separated sometimes by means of these. The question then arises as to whether in case the atoms of an element are not homogeneous they can be separated or detected by physical methods. J. J. Thompson in 1913 devised a method involving the use of the deflecting influence upon the trajectory of an ion by the simultaneous application of elec- tric and magnetic fields and thus obtained evidence of the existence of heterogeneous particles. In some cases further examinations show these to be different molecular aggregations rather than new elements. Thus in hydrogen besides Ho the presence of Ho was proved and there was a possibility of other hydrogen molecules being there. The atomic weight of hydrogen is 1.008. The fractional portion can now be safely regarded as due to an admixture of these heavier molecules. To call such molecular aggregations isotopes would be a serious de- parture from the original definition of the term. They are not dis- tinct and different elements. The term is sometimes carelessly used in the case of molecular aggregations of hydrogen, and other elements and this must lead to needless confusion of ideas. An examination of the monatomic gas neon, whose atomic weight is given as 20.2 reveals the presence of a companion gas having an atomic weight of 22. This corresponds with no known element and the new element is called meta-neon. A physical investigation of at- 120 Journal of the Mitchell Society [3Iarch mospheric neon was then undertaken by Aston. Fractionations by charcoal absorption yielded no results, but fractional diffusion resulted in a partial separation of the two gases. They showed the same properties and gave identical spectra, differing only in atomic weight. More recently the possible existence of another isotope with the atomic weight 21 has been shown. It would seem that heterogeneity has been proved in more than twenty of the common non-radioactive elements. The investigations have been carried on chiefly by the method of Thomson in which the negative electrons were separated and differentiated, and that of Aston in which the positive particles were examined by the application of similar means to the canal rays. Diffusion methods have also been applied with partial success. From the results obtained by either the Thomson or the Aston method the atomic weights can be accurately calculated. It is interesting to note that the results from the Aston method give as whole numbers the atomic weights of all the elements examined. From the examination of chlorine it was found that there were present two distinct elements having the atomic weights of 35 and 37 respectively. There was a possibility of another in much smaller amount with the weight 39. The atomic weight of ordinary chlorine is 35.47 and this is correct to the second decimal place. It is composed mainly of chlorine 35 plus chlorine 37. The relative amounts of these present have been determined and the atomic weight confirmed. In argon a companion element was found in very small amount and this had the atomic weight 36. Kr.ypton gives definite evidence of being a mixture of five isotopes and possibly six. The atomic weights are 84, 86, 82, 83, 80, 78. Xenon also shows the presence of five isotopes with possibilities of two more. The remaining ten in the list of Aston are homogeneous as to atoms but heterogeneous as to molecules. These are H, He, C, N, 0, F, P, S, As, and I. In these cases only two variants were found in each mixture. There is a very striking fact regarding the isotope of helium which was discovered by Eutherford and found to have the mass 3. jAston gives it the atomic weight 4, the same as helium, and that means from his calculations some multiple of 4. It is proper to state that Ruther- ford has questioned the correctness of Aston 's deductions. If Ruther- ford is right, this coincides with the mass of the hydrogen isotope 1922] Isotopes 121 H3, which was discovered by Thomson, confirmed by Aston, and di- rectly prepared by the activation of H by Wendt and Landauer (Amer. Chem. Soc. 1920. 42: 920). Thus we have the two with the same mass — one an isotope of helium and the other a molecular aggre- gation of hydrogen. They are entirely different in properties. Soddy (Lond. Chem. Soc. Ann. Rep. XVII. 221) writes as fol- lows concerning the Aston methods : The methods depend on the same general principles as those (of Thomson) which sufficed to detect the presence of meta-neon, of atomic mass 22, in atmospheric neon but the electromagnetic and electrostatic deviating fields are rearranged in such a way as to secure an effect precisely analogous to focus- sing in optics. The trajectories of the positive ions in a slightly divergent beam are brought to a focus in a plane containing the photographic plate. All those for which the mass divided by the charge is the same are brought to the same point in the plane, those with greater or less values, respectively, being on either side. The complex pencil is resolved into a ' ' mass spectrum ' ' in every respect analogous to a light spectrum produced by a prism or grating. The terms "first-order and second-order mass spectrum" are used to denote spectra pro- duced by ions singly and doubly charged respectively. The existence of ions with more than one unit of charge introduces a complication but fortunately these are experimental peculiarities which enable the two orders usually to be distinguished without uncertainty. The relative mass of the ion causing any line in the spectrum can so be evaluated to an accuracy of one part in a thousand and the atomic mass determined to a degree of accuracy comparable with that attained in the best determinations of the atomic Aveight by chemical means. Incidentally, the complete agreement between the two in many cases affords much the most important evidence of the constancy between mass and weight for different elements Apart from a possible uncertainty, already alluded to, as to the orders of spectrum to which any line belongs, the photographs published reveal the great power and accuracy of the new method. Unfortunately, only non-metallic ele- ments have so far been included. The difficulties in the way of examining metallic elements by this means have not yet been overcome. In every case, except hydrogen, the atomic mass of each homogeneous component proves to be an exact integer in, terms of that of oxygen as 16, within the error of meas- urement already stated. For hydrogen, however, the chemical value 1.008 is ex- actly confirmed and its homogeneity proved. In the year or two that have elapsed since the above citation was written by Soddy several new isotopic elements have been discovered, among them those accompanying certain metals as K, Rb, ]\Ig, and Zn, so some of the difficulties which impeded progress have been overcome. Likewise certain of the atomic weights as determined by chemical means have been very exactly confirmed. Furthermore, Harkins has 122 Journal of the Mitchell Society [Mai'ch recently drawn attention to the inadequacy of the designation ' ' atomic number." He suggests as a substitute "element number" but this seems equally inadequate. The truth is, it is merely a position number and no longer represents either single atoms or simple elements. In his address as president before the recent meeting of the British Association, Thorpe says : The term atomic weight has thus acquired for the chemist an altogether new and much wider significance. It has long been recognized that it has a much deeper import than as a constant useful in chemical arithmetic. For the ordinary purposes of quantitative analysis, of technology, and of trade these constants may be said to be now kuowai with sufficient accuracy. But in view of their bearing on the great problem of the essential nature of matter and on the super- latively grand question, ' ' What is the inner mechanism of the atom ? ' ' they become of supreme importance. Their determination and study must now be approached from entirely new standpoints and by the conjoint action of chemists and i^hysicists. In conclusion, I ask you and myself the question : How shall we now detine the element in the light of these new and wonderful reve- lations? Years ago in an address before the American Association I pointed out how often in the history of science we had been forced to change the definition because of new developments and how shifting were the sands upon which it was based. The homogeneity so fer- vently relied upon in our textbooks must be abandoned as the hetero- geneity of their component particles has been made manifest. One stand is left to us and it has the appearance of permanence. However heterogeneous physically, these component particles are homogeneous chemically. In fact, the sole difference seems to be that of mass. For the present, then, the defiuition may safely run : The masses of all elements are composed of chemically similar particles. So long as this is true the chemist at least need not disturb himself. Of course, there alwaj^s looms before us the fact of atomic disintegration. Chapel Hill, N. C. SOME CONSIDERATIONS IN DEFENSE OF THE GENERAL BIOLOGY COURSE By J. P. GiVLER In the teaching of elementary courses in the biological sciences in America two main policies have been developed during the past half century. In one, the beginning student is introduced to plant biology or animal biology through the medium of a course in Botany or Zo- ology as a distinct entity. The other method, originating with Huxley, is to organize into a single elementary course forms from both plant and animal ' ' kingdoms ' ' to show their essential agreements or to bring out their contrasts. The history of the two policies is well known. The separate course system had its origin in systematic Botany and Zoology since Linnaeus and before his time, through Cuvier and others in Europe and into America principally through the elder Agassiz and Asa Gray at Har- vard. The animus of the General Biology Course, on the other hand, came up from Greek thought, with the viewpoint of the naturalist, out of which the selection theory gained expression through Darwin and Wallace. Parallel with this naturalistic expression developed the general- izations based upon the discover}^ of the meaning of the cell and of protoplasm which generalizations have become incorporated with the Doctrine of Organic Evolution. About sixty years ago Huxley seized the essential features of this cell-protoplasm-evolution complex and, with rare educational genius, framed it in clear outline for the beginner and layman. In this he doubtless secured assistance from Foster and Dyer and inspiration from Darwin. Each of these systems of elementary instruction has its peculiar virtues. That involving separate courses has the advantage of a more restricted field and, further, clings mainly to fact through the dis- ciplines of morphology and taxonomy, while the General Biology Course is animated mainly by ideas and principles from the spirit of the generalizations which gave it birth. As is commonly known the teaching of General Biology entered this country with H, Newell Martin, the physiologist, an early student of Huxley's, and radiated out from Johns Hopkins into a great many institutions in the East and West. During the forty-odd years which [123] 124 Journal of the Mitchell Society [31 arch have elapsed since that time many ehano'es have taken place. The number of colleges and universities including some kind of Biology in their curricula, then small, has multiplied into the hundreds. With this has come about a vast increase in the numl)er and viewpoints of teachers, their leaders primarily interested, as investigators, in ex- tending our knowledge into new fields of an ever broadening and deep- ening science. Along with this must also be reckoned the profound influence of German science upon that of America. As complained of by Professor Carmichael* our science has become practically an appendage of that of Europe (and especially of German.y) as witnessed by the character of the research in most departments of American universities. These various exhaustive and extensive research programs pursued by lead- ing professors and the "schools" which they represent demand dis- tinct limitation in the scientific interests of the workers which, unfor- tunately, spells the extinction of the general point of view. The General Biology Course, on the other hand, was born out of a more generalized condition and in a day of more limited knowledge. Uniting the genius of interpreter with that of investigator, Huxley w^as able to organize out of simple materials a course of great suggest- iveness and value which undoubtedly stimulated many students. The pedagogical theory underlying the course was that each type is both broadly suggestive in itself and also that, through their sequence, evolutionary progress is epitomized. The inclusion of both plant and animal types was defended on the ground "that the study of living bodies is really one discipline, which is divided into Zoology and Botany simply as a matter of convenience. ' ' In the second edition of their textbook Huxley and Martin re- versed the order of animal forms, beginning with the frog, running down to the Protozoa and then up on the plant side to the Angiosperm. From that day to this we have had an unending series of experi- ments in the pedagogy of General Biology among writers in English recalled by the names of Parker, Gibson, Dodge, Boyer, Wells, Need- ham, Hamaker, Sedgwick and Wilson, Abbott, Conn, Calkins and others. Each of these books seems to be the embodiment of a sincere attempt to frame "a general biology" for the beginner in somewhat the spirit of one writing an introduction to philosophy. They disclose many influences. The book l)y Sedgwick and Wilson, Carmichael, R. D., Science, Apr. 1, 1921. 1922] Defense of the General Biology Course 125 really an unfinished task, apparently attempts to combine the Hux- leyan unified view of nature with a strong leaning toward the typi- cally German love of multitudinous details in its rather exhaustive treatment of the fern and the earthworm. Continual experimentation in the order or sequence of presentation of types characterizes these many elementary textbooks. The earlier, and we believe the better, of these works developed directly out of Huxley's influence and, like that of their master, were based solidly on the idea of comparative general morphology and phys- iology. An example of these, and in our judgment, the best that has ever been written, both from a biological as well as from a literary standpoint, is Jeffrey Parker's "Lessons in Elementary Biology." This book embodies the virtuous realization that the student knows only the types presented which must serve as the tangible and material embodiment of the principles drawn therefrom. Unfortunately this fine common sense is nearly absent from many later works in which both author and reader seem to struggle vainly to get feet on solid ground. Many such works embody the results of recent and unconfirmed research, talk much about enzyme action or accessory chromosomes, and give the student the notion that he must reach up and pluck general principles out of thin air. Much poor teaching has been done in the name of "General Biol- ogy," and I revoice some of the criticisms of Professor Nichols* of the Yale Sheffield Scientific School, who not long ago published a de- tailed attack upon the value of this type of course. While believing that his views result, in the main, from bias, many of his points are well taken. Many courses, printed and unprinted, have been futile primarily because their builders fail to recognize the basic principle of any type course — that the types presented embody the realities from which both wider knowledge must spring and on which principles must rest. If this be true for distinct courses in Zoology and Botany, where subject- matter is more limited, it is much more the case in General Biology where the student's thinking may range over a wider field. In our view the essential principle of a course in General Biology is that it be a series of elementary lessons upon a logically arranged series of suggestive type forms. The course should be conducted by a broadly-trained biologist with a view to developing in the student * Nichols, G. E., Science, Dec. 5, 1919. 126 Journal of the jMitciiell Society [3Iarch the attitude of the appeal to nature for facts, upon which accurate thinking is based, as well as that liberation of the spirit which comes from reflection upon their broader meaning. From the standpoint of the student there are two considerations of importance. First, which method will give him the best scientific training in Biology while providing a single view of the entire field of living things, granted that he may find time for no further work in Biology? Second, which method would be preferable in case he decides to go further or finally become a specialist? These complex questions are, in a measure, bound up with the nature of the curricu- lum for, after all, a college exists largely for the purpose of sampling the stock knowledges which have come down to us with our social in- heritance. Biology purports to give an interpretation of the living world. This is a large order, so the student rightfully expects a clear panorama and a guide thereto. In our judgment this is best sup- plied by a course in General Biology whether he elects to go farther or not. The study of plants and animals together in their agreements and contrasts seems to us especially desirable. In our daily lives we deal with complex situations which have little in common beside the fact of their complexity. We learn more about these situations by con- trasting them, the learning process, in life, progressing with the ability to drop out unessential factors. For this the training offered by work in General Biology may afford some practice. Moreover, biologically, the essential characters of organisms as plants, on the one hand, or as animals, on the other, are best brought out by comparison and con- trast. As, in a course in General Biology, this is done on material common to the several biological fields, it seems to us that a course of this character forms the best possible introduction for either the future botanist or zoologist. But w^e are not usually teaching for the benefit of the future s]ie- cialist. Our task, mainly, is to feed the prospective citizen with fcod meet for his symmetrical development. For him, especially, do we see in the well-organized course in General Biology the best possible introduction to a balanced view of the facts of life as it not only epitomizes living nature but also the nature of things throughout time out of which man was evolved. Here we do not find plants by them- selves nor animal life apart but rather that symbiotic relationship for the appreciation of which, in one balanced view, General Biology should stand. 1922] Defense of the General Biology Course 127 That this is not more often satisfactorily done seems to us to be due both to lack of pedagogical sense and judgment and also to the restrictions imposed by too special an early training. Sometimes, also, a very conscientious instructor makes the mistake of being too thor- ough, overloads his types with too many lessons, or chooses the wrong ones for them, reasonably, to illustrate. For example, on visiting a very good college some time ago, I found the notion manifest that, in presenting Amoeba in General Biology, every possible aspect and viewpoint should be stressed, — occurrence, distribution in time and in geographical range, morphology, taxonomy, habits, behavior, oecology, etc. This would, in our judgment, be a proper method for excluding normal students from the course. Moreover, each of the disciplines referred to above was visited upon all succeeding types, seriatim. This is mechanical thoroughness at the expense of both common and artistic sense, and course-making worth the name demands both. In another highly-esteemed college the biologist incorporates in a similar course the notion that it makes no difference at all what par- ticular specimen the student works upon. To begin with one studies an amoeba, another an infusorian, another an alga or diatom or ento- mostracan or annelid. "Why worry?" They each and all embody the principles of Biology ! Moreover, the lectures seem to have nothing to do with the work done in the laboratory. /Among many such teachers is the idea prevalent that "it is per- sonality that educates." All ti-ue, but in this case admirable person- ality survived in spite of handicaps. As well say "let us away with mere educational disciplines and converse with our students about what-not." Nor can one justify the hodge-podge of throwing in now a few animal forms, now a few plants to insure variety. The brighter stu- dents soon get the idea that Biology is a sort of potpourri, a ' ' footless science, " as a physician once expressed it to me. However, a reason- able sense of the spirit and educational philosophy back of good Gen- eral Biology teaching demands that each type be bulwarked with two sets of defenses, one for its individual justification, the other for its right to its place in the sequence in which it stands. In this inheres what might be called "the dramatic unities," a good course needing to resemble a drama to have human and intellectual appeal. Let us reiterate, also, that there is no such thing in science or literature as a continued climax. The plot must be broken up into divisions which are climactic in their sequence. 128 Journal of the Mitchell Society [il/arc/i With these considerations bearing on the nature and conduct of courses in General Biology it remains to be stated that an elementary course of this character appears to become increasingly justified by each new large development in Biology. The essential agreements in ultimate structure between animals and plants brought out by Schlei- den and Schwann, by Max Schultze, by the selection theory and other hypotheses of evolution have been extended by more recent studies on chromosomes and on the mechanism of hereditary transmission. For the justification of the already strategic position of General Biol- ogy in the middle-ground between the two great "kingdoms" it is im- portant to realize that none of these great developments, above named, sprang solely from Botany or Zoology as such but always from laws inherent in the nature of both. If we can judge of the future from the past it seems reasonable to predict that the biological generaliza- tions of the twentieth century, I'ike those of the nineteenth, must emerge from similar common sources. The General Biology Course gives also a peculiar advantage for the presentation of the facts of symbiosis and of interdependence be- tween plants and animals. This aspect has been developed extensively in the textbook by J. G. Needham, and the emphasis is legitimate, for in nature living forms have not evolved alone but as factors of an interdependent symbiogenetic complex of processes. Further, from a broader physico-chemical world view, in the light of Professor Hen- derson's work on "The Fitness of the Environment," we gain even a fuller confidence, that as an introduction to the principles of the science and as the most rational type of course for the beginner. Gen- eral Biology is beyond all question superior to distinct courses in Zoology and Botany. If it be urged that this type of course is too dependent upon the ability and personality of the teacher the answer is that the success of any course is likewise largely thus dependent. No subject will teach itself. Although biological principles in education are not always to be taken literally, as shown by the misuse of the biogenetic law as ap- plied to primary education, there are here applicable suggestive evolu- tionary principles which are of interest. The principal lesson of evolu- tion is not that man is an unfolded amoeba but that all life is one. Further, no evolutionary principle is more important than that the great groups of living forms, surcharged with capacity for adaptive 1922] Defense of the General Biology Course 129 radiation, have sprung' from generalized ancestors low down on the main stem of the evolutionary tree. In the organization of scientific courses the analogy seems justified that the more generalized the ap- proach the wider its suggestivaness, the greater the possibilities of future adaptation on a firm substructure into a widely-ranging gamut of specialized possibilities. It is further our belief that General Biology should be prerequisite to beginning courses in Zoology and Botany as such, as well as for special work in Bacteriology and Physiology in which courses pro- grams of laboratory work and lectures may be organized of much greater strength and thoroughness than would be possible with stu- dents having no such general background. A further advantage in- heres in the fact that such courses in Botany, Zoology, or other special fields, attract mainlj^ only those who feel some beginnings of a special interest and fitness for work in these specialized directions. An econ- omy of both equipment and effort is thus effected. The North Carolina College for Women. Greensboro, N. C. NOTES ON THE OECOLOGY AND LIFE-HISTORY OF THE TEXAS HORNED LIZARD, PHRYNOSOMA C0RNUTU3I Y By J. P. GiVLER It was my privilege during two summers spent in a study of Phry- nosoma in southern Kansas* to observe and record many facts of bionomic interest in relation to this well-known creature. The region named also made available for study directly in the field, in comparison with Phrynosoma, representatives of several other genera and four families of Lacertilia. In the laboratory comparative studies were made of general morphology, reproductive organs, eggs and embryos. The following account is intended to serve as a record of some of these observations and to present in one view a brief account of the bionomics of reproduction of this reptile. EMERGENCE FROM HIBERNATION In southern Kansas the Texas Horned Lizard comes forth about May first. When the ''toads" first appear in the spring they are thin and emaciated, sluggish, and very dark in color, ^t first the males greatly preponderate over the females in numbers, being in the ratio of three or four males to one female. Later the females emerge in greater numbers, tending to equalize the sexes. From the beginning of their life, ex-hiberna, their activity is de- pendent, principally, upon the sun's light and heat. In the morning they are very sluggish and, when touched, will scarcely move. Later, as they become warmed by the sun, they run about, seek ants and other insects as food and move with a sudden characteristic impetu- osity. They are warned at the slightest sound or movement and fre- quently stop to raise and lower themselves by their front legs, an amusing habit to be appreciated fully only by those who have seen it. During these early days of spring the Phrynosomas mate freely, the preponderance of males at the outstart, as well as the gradual emergence of the females, insuring the insemination of all of the latter. This is attested to by the fact that, among hundreds of eggs studied, only one was found infertile. SEXUAL DIMORPHISM Winton ('14) states for this species observed farther south that, especially in early spring, the yellow cervical crescents are much Winfield and vicinity. [130] 1922] Notes on the Texas Horned Lizard 131 brighter in the females than in the males. This we were never able to find true of our Kansas specimens. Also, while Bryant ( '11) states for the entire genus Phrynosoma, that "the presence of enlarged post- anal scales in the male is a dependable character for determining sex," we have not been able to observe such difference in P. cornutum from southern Kansas and northern Oklahoma. In my experience positive separation of the sexes may be made in this species on the following criteria of body form. The torso of the males, between axilla and groin, is short and cir- cular; of the females long and elliptical. The tail in the males is longer and distinctly swollen at the root, both laterally and ventrally, due to the contained hemipenes. The tail in the female is shorter and tapers more rapidly from its base backward. It also lacks the basal swellings. The sex of juveniles may likewise be determined on these criteria while that of advanced embrj'cs is apparent from the presence or absence of hemipenes. the ovaries In females opened early in May and prior to ovulation the ovaries present an interesting picture. Most conspicuous in each is a collection of about sixteen large eggs, yellov/ in color, at first about 7 mm. in diameter but later swelling to 8 or 9 mm. at the time of ovulation, surrounded by delicate follicles and globular in form except for flat- tening due to mutual pressure. While the number in each group is not constant there tend to be sixteen, making a total for the two ovaries of about thirty-two large eggs ready for ovulation. In some eases there are but ten or twelve eggs in each large group, in others, and but rarely, seventeen or eighteen. Examined separately, each egg displays a germinal disc clearly visible through the follicle and directed toward the point of attach- ment in the mesovarium. The disc is white, circular and about 1^^ mm. in diameter. The borders, although fairly distinct, shade into the surrounding yolk. At the center of the disc is a small, yet dis- tinct, nucleus, about 0.5 mm. in diameter, and clearly discernible in good light to the unaided eye. Dorsad of these groups of large eggs ready for la.ying are to be found, in each ovary, eggs of smaller size, two to three mm. in diam- eter, and provided, each, with a small amount of yolk. These smaller 132 Journal of the Mitchell Society [March eggs are, in each ovary, divided into two groiijDs, one placed laterally, the other mesially in relation to the mesovarium. Still further dorsad, or lying among, this second group of eggs, are ova of a third order as to size, as yet clear and apparently alecithal. The condition here observed obtains, doubtless, in many other vertebrates which show a strictly annual periodicity in their egg-lay- ing. So far as we know ovulation in this species takes place rather suddenly, the thirty-two-odd ripe follicles undergoing dehiscence within a few hours, leaving the empty follicles to be resorbed and al- lowing the next order, or half -grown eggs, to develop to full size during the year following. Meantime the third, or smallest group, from among the remaining oogonia, acquires yolk in its turn. Thus, in Phrynosoma, we observe, in correlation with an annual periodicity in egg-group ovulation, an annual initiation of yolk-secretion by the follicles of groups of undeveloped oocytes against the layings of future years. According to the terms of this hypothesis the secretion of the yolk of any egg requires two years. the oviducts In birds the ova are treated seriatim by the oviduct in the laying down upon them of the albumen, shell-membranes, and shell. The ovi- duct of the Homed Lizard, on the contrary, is adapted to the simul- taneous investment with albumen and shell of sixteen or more eggs carried tandem in its coils. A seriation in this process along the two egg-strings is practically absent, the albumen, which is serous in con- sistency and very small in amount, as well as the shell, being evidently secreted by the same region of the duct in situ rather than by suc- cessive regions traversed by the egg in its course. OVULATION AND EARLY DEVELOPMENT From a number of observations it is evident that, in Phry^iosoma, maturation occurs immediately prior to ovulation and that fertiliza- tion ensues immediately upon the entrance of the egg into the ostium. In studies of lacertilian embryology the securing of segmentation stages is, however, very difficult. The writer was able to confirm the statement of Peter ( '04) that there is no relation between the time of copulation and that of ovulation. Further, the same female may copulate more than once. Having no way to tell the exact hour of ovulation no method has, 1922] Notes on the Texas Horned Lizard 133 to date, been published whereby the early segmentation stages might be found except by accident. Thus the series of embryos of Lacerta agilis, described and figured by Peter in his Normentafel, required six summers to complete. In my work on Phrynosoma, after much practice in external palpa- tion as well as in dissection of apparently gravid females, it became possible, in many cases, by palpation only, to distinguish between ovarian eggs and those which had passed into the ducts. The mass of large ovarian eggs is always smaller in area and more dense, that of the oviducal eggs more diffuse and softer. I found, however, that the two conditions, unfortunately, merge at just the critical time, i. e., with approaching ovulation the ovarian eggs become larger, softer, and less well-defined, which condition merges with that of the early oviducal ova. After much vexation caused by the sacrificing of females in which ovulation had not yet occurred and others in which the embryos were too far advanced, and after seeking, in vain, aid through use of the flouroscope, I discovered that exploratory operations do the creatures practically no harm and hold out much promise for future success in this field of embryology. The animals recover and may be opened and sewed up again several times. If seeking segmentation stages one may thus await ovulation. If the eggs have passed into the ducts one of the latter may be dissected loose, ligatured at base and removed with its eggs, the other being left to develop further. It is interesting to observe that, whereas we are unable to explain the cause of ovulation the dehiscence of about thirty-two large folli- cles takes place, so far as we know, almost simultaneously. A change so momentous requires an adequate cause. Up to the time of ovulation the ova are held firmly in their follicles. (There are no visible cica- trices in Phrynosoma.) Then, suddenly, the ova are all shelled out and rapidly engulfed by the ostia. The time-relation between copulation and ovulation has been much studied by vertebrate embryologists with two main results. In some vertebrates, as in the rabbit, a definite interval (nine or ten hours) has been found to exist. In others, as the lizards, there is no known time-relation. Although we have no evidence to that effect it is our belief that ovulation in Phrynosoma must depend upon the liberation of a hor- 134 Journal of the jMitchell Society [31 arch mone, — where, and under what circumstances secreted we are now un- able to state. GENERAL FEATURES OF EMBRYONIC DEVELOPMENT In the correlation of stages in lacertilian embryology we are greatly aided by the Normentafel of Peter ('04), on Lacerta agilis, in the Keibel series. But while in general parallel, the ontogenetic develop- ment of Phrynosoma is more extended and, in the later or foetal stages, much more specialized than that of Lacerta. These later differences depend but little on any diversities inherent in the two families rep- resented but rather on the emergence of highly specialized generic characters, such as the shortened and broadened body, horns, and rosettes of scales, the appearance of which overpowers the more fun- damental iguanid characters. We are here, however, concerned with the oecology of this reptile in relation to reproduction. As one species of Phrynosoma is vivip- arous and others oviparous an interesting problem exists in the re- lation of the period of egg-laying to the stage of development attained at that time. In the common fowl the egg is laid while the embryo is undergoing later segmentation. In lizards the eggs are usually re- tained much longer, the coelomic cavity of the mother serving as an incubation chamber for the eggs lying within the convoluted oviducts. The precise stage at which laying takes place seems to be a matter of no consequence, lending itself easily to the development of the ovo- viviparous habit of P. douglassi, in which species the eggs hatch while or immediately after being laid. There is reason, also, for the belief that captivity extends the pre-laying period, in reptiles, by several stages. In P. cornutum 1 found little constancy in this matter, some laid eggs being as early as Peter 's stage 22, others as late as stage 28 or 30. Lizards being poikilothermal much must depend on the temperature of soil and air as well as on the time necessary for the gravid female to find a situation suitable for a nest. Specialized generic and specific characters also here tend to prolong the ontogenetic period within the egg and to extend it beyond the range of Peter's series, his final stage (36) being comparable to Phrynosoma embryos several days and stages removed from the laying period. As above stated the coelomic cavity serves, during the breeding season, as a brood-pouch, the 30 or 35 eggs packing it so full that 1922] Notes on the Texas Horned Lizard 135 gravid females present a ' ' stuffed ' ' appearance. Within their leathery shells the eggs float in a sero-albuminous liquid and so easily that the blastoderms, after the shells are formed, invariably float upward, as in the laid eggs of the fowl, directed toward the back of the mother on which the rays cf the sun fall. During the first few hours after the ova are received by the ostia, and before the shells are formed, the germinal discs are directed cephalad, a circumstance which seems to spell suction by the ostium, the discs of the ovarian eggs being invari- ably directed dorsad and away from the point of dehiscence of the follicles. |As the body of the mother is much flattened the eggs lie usually in but one layer and never far from the dorsal surface. The utility of this form of body as an incubator is thus evident. the role of wandering mesenchyme cells As shown by Jarvis ('08) the germ-cells of Phrynosoma arise out- side the embryo upon the yolk-sac and migrate along the yolk-stalk to the germinal ridges. Stockard ('15), more recently, has made an elaborate study of the role of wandering mesenchyme, showing its importance in the development of Fundulus, It was my privilege, in the examination of embryos of many stages in Phrynosoma, under the binocular, both to observe the development of the circulation and its course in the embryonic vessels, and also to witness the importance of extra-embryonic amoeboid cells (wandering mesenchyme?) which appear in large numbers in the yolk beneath the embryo in this lizard. Very soon after embryonic development begins these amoeboid cells may be found, first in a thin layer and later in a disc-shaped mass, in the thin yolk under the embryo. The mass referred to is of a yellow- ish-green color. The individual cells are hyaline or faintly granular and show active amoeboid movement. That these cells are important in many ways in histogenesis seems certain. They warrant a thorough study in this or a related reptile in the spirit of Stockard 's work on Fundulus. EGG-LAYING AND INCUBATION IN THE NESTS The nest-building and egg-lajdng habits of this species have been studied by Strecker ( '08 ) in Texas and my observations are in essen- tial agreement with his. The female digs out a slanting burrow several inches in depth on a sloping hillside and prefers a site just 136 Journal of the Mitchell Society [3Iarch under a projecting ledge of rock. While it may be unwarranted to state as a general principle, all nests that I have observed faced the east. The burrow excavated to such depth that the female is about hid- den from view, she lays therein the cream-white, leathery-skinned eggs. The eggs are elliptical in form and measure 15 mm. in length by 10 to 11 mm. in diameter. They are dropped into the burrow one at a time. Each egg is covered over with a thin layer of dirt, scraped down by the hind legs of the mother, before the next egg is laid. Finally, the eggs all laid, the female packs the nest with the remaining dirt, smoothes it off and scurries away. After a day or two, the site is indistinguishable. So far as known to the writer egg-laying may occur, in Kansas, anywhere between the end of May and sometime late in July. I have no facts to offer regarding the duration of the incubation period which Strecker states to be from 35 to 40 days in Texas, except that it must vary with the stage reached at laying and the temperature. During this entire study no aspect was more interesting than that of the mutual fitness of the developing eggs in their envelopes with that of their earth-nest environment, which serves as a temperature and moisture-controlling brood-pouch. Through some inherited complex of instincts the female selects a site combining the advantage of drain- age, rooting, exposure to heating b}^ the sun, and ventilation. Under certain conditions they become turgid and swell, but shrivel like a raisin when allowed to dry. When the latter occurs the eggs are vulnerable to the attacks of ants, the mandibles of the insects cutting through the folds of the shell. When the shell is turgid and smooth the ants can do nothing of the kind. Daily observing the creatures in their environment the realization is born in upon one that they are literally autochthones, born of the careful regulation of conditions in which they have evolved. development of characteristic external features OF the embryo In so brief an account but little may be said upon this subject except to state that the early stages, as shown by the figures here demonstrated, are characteristically reptilian. About stage 32, how- ever, phrynosoman characters put in their appearance, the rosettes of large dorsal scales being heralded by single rounded protuberances. 1922] Notes on the Texas Horned Lizard 137 At the same time the Iguanid tail shrivels clistally to the more abbre- viated condition of Phrynosoma. Later, stage 33, the surrounding circlet of scales, appearing in the adult around the large dorsal scales, is laid down as an annular anlage, later to be pinched off into its separate scalar elements. Pigmentation first appears in the cervical bilateral patches as black markings about stage 35. Kapidly thereafter the pigment appears in the large scalar rosettes caudad. It is interesting to observe that, in the spread of this fundamental scheme of pigmentation, two gradients are to be observed, one spreading caudad, the other laterad. As might be expected the horns, characteristic of these lizards, are late in appearing, being seen first with stage 36. The newly-hatched young are pale in color, precocial, and may be found within a verj' few days, seeking insect food in the manner of their elders. The North Carolina College for Women. Greensboro, N. C. LITEEATUEE CITED Bryant, H. C. : The Horned Lizards of California and Nevada of the Genera Pryuosoma and Anota, Univ. of Cal. Pub. in Zool., g, No. 1 : 1. 1911. Jarvis, May M.: The Segregation of the Germ-cells of Phrynosoma cornutum: Preliminary Note. Biol. Bulletin, 15. 1908. Peter, K. : Normentafel zur Entwieklungsgeschichte der Zauneidechse (Lacerta agilis) ; (Normentafeln zur Entw. der Wirbeltiere von F. Keibel, Heft 4). Jena, Gust. Fischer, p. 165. 1904. Stockard, C. E. : An Experimental Analysis of the Origin of Blood and Vascular Endothelium. II. A study of wandering mesenchymal cells on the living yolk-sac and their developmental products : chromatophores, vascular en- dothelium, and blood-cells. Amer. Jour, of Anat. 18, Nos. 2 and 3, Sept, and Nov., 1915. Strecker, J. K. : Notes on the Breeding Habits of Phrynosoma cornutum and Other Texas Lizards. Proc. Soc. Washington, 21:165, 1908. Winton, W. M. : A Note On Distinction of the Sexes in Phrynosoma. Science, N. S. 1026:311. 1914. A MAGNETITE-MARBLE ORE AT LANSING, N. C* By W. S. Bayley Plates 24-27 introduction Near the village of Lansing in Ashe County, N. C., is an iron mine from which is being taken an ore which differs materially from all other iron ores in the State and which resembles in some respects the iron ores obtained from the Franklin limestone in New Jersey. The mine which is the property of the Ashe Mining Co., is on the Virginia- Carolina Railroad alongside Horse Creek, and about half a mile south- east of Lansing Station. (See map, pi. 24.) Pratt^ refers to the locality under the name of the Waughbank property as follows : "About 100 3'ards from the creek a tunnel was run by the Penna. Steel Co. The tunnel has a direction of N. 40° E., and at a distance of 100 feet a crosscut was made extending 46 feet S. 40° W. ' ' This crosscut showed ore for its whole distance, making the width of the ore deposit over 30 feet. This ore is composed of coarse granular magnetite in a matrix composed of micaceous material and manganese oxide." The vein was estimated by Pratt to be 70% ore. Analyses of a fair sample of the vein (I) and of a selected sample of the mag- netite (II) gave: Fe Mn PS Ti I 46.25 4.34 .026 .027 tr II 67.25 1.68 This is evidently the same deposit as that described by Nitze^ as " Ballon 's Horse Creek ore bank." At the time Nitze wrote the opening w^as in the "shape of an undercut in the side of the hill into which it extends perhaps 50' as a slope." The seam, the dip of which *'is apparently towards the northeast," is at least six feet M^ide, the lower two feet being the harder. Nitze 's analyses correspond closely with those furnished by Pratt. They are as follows : SiOj Fe Mn s P P ratio 1.96 62.48 3.66 .072 .019 .030 4.58 54.02 6.85 .007 .011 .017 * Published with the permission of the Director of the IT. S. Geological Survey and the Director of the N. C. Geological and Economic Survey. 1 Pratt, J. H., The Mining Industry in North Carolina during 1911 and 1912. N. C. Geol. and Econ. Survev, Economic Paper No. 34, p. 68. 1914. 2 Nitze, H. B. C, Iron Ores of North Carolina. N. C. Geol. Survey, Bull. No. 1, p. 156. lCt»3. [138] Portions of Cranberry, Abingdon, Wytheville, and Wilkesboro fjiiadrangles, showing position of mine at Lansing, N. C. 1922] A Magnetite-Marble Ore at Lansing, N. C. 139 Capt. Geo. W. Cooke, who is operating the mine for the company, declares that the present mine is on the Waughbank property but that the original opening which dates back as early as 1828 was on top of the hill about 50 feet above the present tunnel and was in an entirely different kind of ore, The tunnel of the Penna. Steel Co. was opened about 15 years ago into the lower portion of the Waughbank deposit. It is parallel to the present tunnel, about 40 feet above it and about 100 feet further west. It is frequently referred to as the upper level. 'At its end, at the bottom of the AVaughbank pit, a little limestone ore was encountered, but most of the ore developed by it was of the sili- ceous type like that at Cranberry. The relations of the two tunnels to one another and the mutual relationships of the siliceous ore and that now being worked are shown in the sketch, pi. 25. THE ASHE MINING COMPANY'S MINE Mineral Conhposition of the Ore : — The ore of the deposit now being worked is essentially a coarsely granular intermixture of mag- nesian marble and magnetite (pi. 26). Here and there are particles of quartz but they are rare. The carbonates are in large grains with perfect cleavage constituting a white marble. The magnetite is in irregular though slightly elongated grains scattered through the marble, producing an ill-defined schistosity, which is emphasized by the occasional accumulation of the magnetite grains in lenses with their long axes parallel to the obscure schistosity of the matrix of carbonates and magnetite in which thej' lie. (See pi. 26.) In a few places the rock is markedly schistose. This is brought about either by the oc- currence of many of the magnetite grains in plates, suggesting the plates of hematite in specular ores, or by its occurrence in numerous small lenses elongate in parallel directions. Many of the elongate grains are sheared and drawn out into lines or rows of sharp-edged particles. The carbonate grains associated with the magnetite show no similar elongation, but the schistosity is often accentuated by the presence of calcite veins or layers running in the same direction as the lines of magnetite plates. Evidently the carbonates have been en- tirely recrystallized since the rock's deformation. Here and there through the mass are embedded small garnets, which in many cases are altered so as to give rise to light brown stains. A typical lean ore in thin section shows coarse-grained aggregates of two colorless carbonates, of which one is calcite and the other prob- 140 Journal of the Mitchell Society [March ably dolomite, a few plates of phlogopite and large irregular masses of magnetite. The mica is in streaks of plates extending in nearly straight lines through the section with the individual plates lying be- tween adjoining carbonate grains and more frequently than otherwise near the magnetite. This mineral is often in large areas with very ragged boundaries, the salients of which project considerable distances between the grains of carbonate, or between contiguous twinning lamellae. Occasionally^ a smaller grain appears to be enclosed in grains of what is regarded as dolomite, and in other instances the larger masses appear to enclose small grains of the carbonate. From the fact that the carbonate inclusions polarize uniformly with the large car-, bonate grains surrounding the magnetite it is thought that the ap- parent inclusions are merely portions of projections that extend into the embayments of the magnetite and that their appearance as inclu- sions surrounded by magnetite is due to the fact that the section was cut through the boundary between magnetite and carbonate. The richer ore differs from the poorer ore mainly in the larger sizes of the distributed magnetite grains and especially in the much greater sizes of the magnetite lenses. Some of the latter are a foot or more in length and five or six inches in diameter. A photograph showing the contact of one of the lenses with the surrounding marble is reproduced in pi. 26. The greater portion of the ore, as has been related, is mainly a coarsely crystalline marble containing grains and lenses of magnetite. In many places, however, it contains dike-like masses of a bright green color, which proves to be a fine-grained aggregate, mainly of granular actinolite which, where shearing occurs, is changed to a mass of fibres of bright green actinolite. Often magnetite is present in the granular aggregate, and this is noticeably more abundant near the contact of the green layer with the marble. Indeed it not infrequently happens that there are distinct lenses of magnetite at the contacts of the two rocks even though magnetite may not be present elsewhere in association with the green rock, and occasionally a continuous thin layer of magnetite separates the two for considerable distances. The actinolite layer passes into the carbonate rock by a very gradual tran- sition— the, actinolite becoming less and less abundant until it forms a very small portion of the mass. In this section the actinolite mass is discovered in reality to be complex. It consists of an aggregate of thin layers and fiat lenses PLATE 25 J) Ma. oh.e.fLte-jYCcurhle. Ore, I I Sill. Le.0 u. 3 Oyg. F~l Tiotk Sckisfi, arid awrtfe TKe. d'lps are. of contacts S c Q.le i-n. (■ < .^t Plan and sections of Ashe Mining' Ooiii))any'.s mine, Lansing, N. C. (Miip Inriii.vlied by Geo. W. Cooke, Manager.) 1922] A Magnetite-Marble Ore at Lansing, N. C. 141 made up mainly of equi-dimensional prisms of actinolite that are pleochroie in very light yellowish green and emerald-green tints. These alternate with equally thin layers of carbonates. The maximum extinction of the actinolite is about 20°. Among the actinolite prisms are scattered a few large grains of carbonate, a very few large plates of a colorless mica, perhaps phlogopite, and large irregular masses of magnetite. The actinolite appears as though in crush zones, and its individual prisms have a general parallel elongation in the direction of the layers. In many cases the magnetite masses are crossed by tiny cracks filled with calcite. It is noticeable that the major portion of the magnetite within the layer characterized by the actinolite is usu- ally associated with the carbonates that are always present in it. In some places, however, the magnetite and actinolite are so free from carbonates that the rock is locally a magnetite-actinolite schist. Around the lenses of magnetite in the marble are often envelopes of actinolite and often there are veins of actinolite cutting through them. In these cases the magnetite is cleaved so that the lenses appear to be granular masses composed of elongate grains of the magnetite. The long dimensions of the magnetite and the long directions of the actinolite fibers in the veins are parallel, but there is no definite re- lation between the elongation of the fibers and the directions of the veins. The fibrcsity may be parallel to the walls of the veins, per- pendicular thereto, or inclined to them at any angle. Whatever their direction with respect to the veins, they are all parallel within the mass of a single hand-specimen. In other specimens veins of actinolite traverse masses of magnetite and marble, and sporadic garnets appear in the mass. The suggestion furnished by the sections is that a mass of marble and magnetite, with some actinolite, became shattered as the result of movements, and the cracks between the fragments of magnetite were filled with actinolite formed from magnetite and some of the constit- uents of the marble by metamorphosing processes during the course of this movement. In some cases calcite which was undergoing recrys- tallization at the time was also forced into the fractures. There was evidently motion in the rock-mass also after the actino- lite was formed and after the magnetite was shattered, since there are present in the rock sliekensides coated with acicular actinolite, in many cases to a thickness of one-half an inch or more. Inthese cases there 142 Journal of the Mitchell Society [March are usually layers of ma<^netite next to the actinolite, and in the mag- netite are frequently small streaks of pyrite. That these various de- formations produced little effect upon the structure of the carbonates is due no doubt to the fact that these have recrystallized since the action of the forces producing the deformations ceased. Here and there through the ore there is also considerable dark hornblende. It occurs in large (piantity in some fragments on the mine dump. It apparently is in fairly large dikes in which horn- blende, magnetite and frequently garnet are intermingled. Where the hornblende .is in dikes a foot or more wide their interiors are coarse black hornblende free of garnet. In the smaller dikes, on the other hand, the hornblende masses often enclosed small lenses of lime- stone, which have been nearly completely changed to pink garnet. In some instances garnet and hornblende are in equal quantities. The limestone in contact with the hornblende is often banded and it fre- quently contains lenses of magnetite. In contact with the hornblende- garnet is a narrow layer of tine-grained hornblende, carbonates and pyrite with the latter usually in very thin seams parallel to the bound- ary. Beyond this are bands of carbonates and magnetite and of carbonates and black mica. The banding is thus the result of con- secutive layers of coarse black hornblende, aggregates of black horn- blende and red garnet, aggregates of fine-grained dark and light horn- blende, thin seams of pyrite and of carbonates, streaks of magnetite and finally layers of carbonate and black mica. There is no common elongation of the carbonate grains in the limestone, but the rock in the neighborhood of the dikes has a distinct sehistosity due to the parallel arrangement of the layers. Often near the borders of the ore deposit and occasionally within its mass are also irregular aggregates of red garnet, black hornblende, magnetite and carbonates in which the garnet is predominant. The hornblende on the whole looks as though it were intrusive and the garnet as though it were a contact product between hornblende and the carbonates. These aggregates are traversed by little veins of white calcite and colorless quartz and contain here and there nests of these minerals, which are unquestionably secondary. Pyrite is not common anywhere in the ore. It occasionally occurs as thin layers between the layers of granular, light green hornblende and the marble, and in a few places scattered through the magnetite- PLATE 26 ^y:>v^. (Above) PHOTUGKAPH OK ORE FROM MfNE AT J^AiNSING, N. 0. NAT. SIZK. (Below) PHOTOGRAPH SHOWING COXTAGT OF ORK LENS WITH MARBLE IN ORE FROM MINE AT I;ANSIN(i. N. V. J922] A Magnetite-Marble Ore at Lansing, N. C. 143 marble rock in large masses that enclose particles of the other com- ponents. Some of the particles are plainly large skeleton cubes, poiki- litically developed. In other words, they possess the sieve structure which is characteristic of minerals formed later than the rock in which they are found. In some cases the pyrite apparently replaces calcite and in other cases magnetite. It is believed that it was not a part of the original rock but was subsequently introduced. Veins in the Ore : — In places fine-grained feldspar-quartz veins cut the hornblende-magnetite masses. In thin section the vein rock is seen to be badly crushed — the quartz areas are aggregates of small quartz grains and the former feldspar grains are now aggregates of small, Yevy light yellow epidote grains. There are, however, no sharp boundaries between the feldspar and the quartz areas. These have been obliterated by the crushing. The quartz areas near their borders are full of epidote grains and the epidote areas contain nests of quartz grains and, further within their interiors, individual grains of quartz. Moreover there are little veins of epidote in the quartz, and vein-like lenses of quartz in the epidote aggregates. The contacts of the veins and the hornblende masses are also far from sharp. Occasionally there is a streak of small pink garnets sepa- rating the two, but for most of the distance the epidote aggregate pen- etrates the hornblende mass, and hornblende grains are embedded in the epidote. The hornblende mass consists mainly of large crystalloids of hornblende — j^ellow-green — with large nuclei composed mainly of partly amphibolized light yellowish augite. Often the partially al- tered pyroxene comprises three-fourths of the area of the grain, and around it is a zone of compact green-yellow hornblende with sharp fibrous projections extending from the more compact portion. Ex- tinctions of 24° against the cleavage in the surrounding zone and of 45° in the nucleus are characteristic. In the spaces between neighbor- ing pieces of hornblende are small nests of quartz and calcite and often in pieces of the amphibole that are not so compact are enclosures of quartz and many more of calcite. Often the areas between the large amphibole grains are filled with quartz and carbonate grains and spicules of green hornblende, but in no case seen do the spicules actually cut through the carbonate and quartz. These minerals appar- ently simply fill in the spaces between the spicules. These fine-grained veins are believed to be small veins of pegmatite 144 Journal of the Mitchell Society [March that have been completelj- oTanulitized, and tlius have lost all traces of their granular structure. It is significant that few garnets occur at their contacts with the hornblende through which they pass, but that, on the other hand, garnets are frequently found between the hornblende masses and the mar])le surrounding them. Where peg- matites cut the country gneiss in the vicinity of the mine large garnets occur in the gneisses near the contact. It may be fair to assume there- fore that the hornblende masses are a part of the pegmatite, since upon this assumption the presence of garnets between them and the marble is easily explained as due to contact action. Moreover, the hornblende is an altered augite — and in the Cranberry area in Avery County the pegmatites associated with the ore were originall}'' an augitic variety. The relations of the pegmatite, hornblende and carbonates, to- gether with the presence of garnets and of streaks of magnetite near the borders of the hornblende are suggestive of contact action. In the old Waughbank Mine the ore was of the same character as that in the Cranbei-ry Mine. If the views of Mr. Cooke are correct the Waughbank ore gradually passed into the limestone ore now charac- terizing the Ashe Mining Company 's INIine. There is very little definite pegmatite in the present mine unless it is represented by the horn- blende streaks and the fine-grained veins described above, but there is pegmatite in abundance in the old Waughbank openings. The horn- blende streaks in the mine now operating may very well have been very basic phases of augitic pegmatite, which added iron and perhaps silica to the limestone and brought about contact action by which gar- nets, phlogopite and actinolite were produced. Chemical Composition of the Ore: — A selected sample of the rich- est ore freed from adhering limestone was analyzed b.v J. G. Fairchild of the U. S. Geological Survey, with the result shown below. The anal- ysis^ of the magnetite separated from the ore of the Ahles Mine in New Jersey is given in II for comparison. The Ahles ore is in limestone. ^ Bayley, W. S. Iron Mines aiid Mining in New Jersey. Vol. VII of Final Report Series o.' State (Jeologist, Trenton, N. J., 1910, p. 111. 1922] A Magnetite-]\Iakble Ore at Lansing, N. C. 145 CHEMICAL COMPOSITION OP MAGNETITE FROM THE LANSING MINE, N. C, AND THE AHLES MINE, N. J. I II iSiOj 2.33 1U.60 AljO^ 2.38 1.8d FeA 60.42 48.44 Cr^Os .00 FeO 24.80 29.32 MnO 3.01 MnOj = 4.19 MgO 3.37 .62 CaO 1,14 .29 Na.O 26 -^o K.O tr TiO. tr tr C02 1.97 PA tr tr SO3 11 .06 HoO— 04 1.36 H,0+ 83 2.55 S 00 VA 00 BaO 00 .41 SrO 00 F 00 100.66 99.81 The analysis of the Lansing ore is that of a very pure magnetic ore. A calculation indicates the presence in it of the following com- ponents : CALCULATED MINERAL COMPOSITION OF LANSING ORE Magnetite 81.0 Limonite -J-O Pyrolusite •--'j Dolomite -i-J Pyrite I Silicates 6.2 100.0 The magnetite is remarkahly pure. It evidently contains a little manganese, but is free from titanium. In these respects it closely resembles the magnetites in the Franklin limestone in New Jersej'."* The percentage of Fe indicated by the analysis is 61.58% and of Bayley. W. S. Final Report Series of the State Geologist (New Jersey), 7: 111. 1910. 146 Journal of the Mitchell Society [March Mn 2.33%, but this analysis is of a selected sample from which ma- terial other than magnetite has been removed as thoroughly as possible b}' careful hand-picking. The ore furnished to the Cranberrj' Furnace is shipped as taken from the mine, without crushing and careful se- lection. This, therefore, is much lower in iron, and indeed consider- ably lower than the minimum limit for ordinary magnetic ore ; but because of its extremely low phosphorus and high calcium is acceptable. Some of the marble-magnetite is too poor in iron to be regarded as an ore, but by rejecting this the balance passes as an ore which though possibly low grade with respect to iron is available to the furnace because practically all the material that is not iron is a mix- ture of calcite and dolomite which serves as a flux. An anah'sis of an average specimen of the marble made in the laboratory of the U. S. Geol. Survey by Mr. Fairchild gave: MgO = 9.17 ^r, CaO = 26.32%, and CO., = 34.28%, corresponding to a mixture of MgCO.^ and CaCOg in the proportions 1 :2, and an excess of 31/9% COo, a large part of which is in MnCOo. Analyses of many carload lots of ore made at the Cranberry Fur- nace at Johnson City prior to the summer of 1919 showed limits of 36.43-52.93 for Fe and .0094-.0n4 for P. A series of analyses of 7 cars received during the summer of 1919 gave :^ Iron 40.65 42.76 46.46 39.07 40.65 35.11 38.54 Fhosphorus 006ii .0052 .0052 .0052 .0042 .0062 .0057 One analysis'' of a car of ore very low in iron yielded Fe = 30.52, P = .0052 and CaO = 17.84. This is equivalent to 42.14% magnetite and 31.867o CaCO., or a total of 76%. There was no record made of the other 24%. The Ore Body : — The ore body of the mine is reached by a tunnel running 150 feet into the base of tlie hill just above the level of Horse Creek in a direction N. 40° E. It is in the foot wall, Avhich is a light gray hornblendic gneiss that may belong with Keith's Cranl)erry granite, which is archean in age. Between this gneiss and the ore- body is a thin layer of gray mica schist, that may readily be a result of shearing of the gneiss along the contact. Immediately above the ore is another thin sheet of a similar schist and above this a light gray fine-grained gneiss that may be a part of the Cranberry granite. 5 Furnished by Pres. F. P. Howe, Cranberry Furnace Co., Johnson City, Tenn. " Made by Cranberry Furnace Co. Furnished by Mr. Cooke. 1922] A Magnetite-Marble Ore at Lansing, N. C. 147 The greater part of the country rock is a coarse gray banded gneiss that looks very much like a squeezed porphyritic hornblende granite, perhaps a phase of the Blowing Rock gneiss, also placed by Keith in the archean. This is interlayered with light-colored gneiss which was originally an augitic syenite. It now consists of large anhedrons of a microperthitic feldspar, large light green masses of amphibole, con- taining here and there nuclei of pyroxene, and surrounded by a border of tiny epidote crystals lying in all azimuths. There are also present a small quantity of brown biotite and a few large grains of quartz. The feldspars are crushed around their edges into a fine-grained mass which now consists of quartz, epidote and pale green amphibole. These gneisses are intersected by veins of pegmatite that is almost devoid of dark components, and on the borders of which are large garnets. In many instances the feldspar of the pegmatites is partially changed to epidote as at Cranberry. In a cut on the railroad layers of hornblende schist are in the gneisses, and along these shearing took place with the production of actinolite-asbestos. The ore body is sharply marked off from the country rock by the layers of schist below and above. In shape it appears to be irregular. In general it strikes a few degrees E. of North and dips about 36° S. E. In a portion of its course the dip and strike are regular, indi- cating a width of only four feet and in some places the ore is cut out entirely by what appear to be great fragments of the country rock or by small faults. Near the present end of the tunnel the ore body was apparently chimney-like. It was encountered in an old hole on the surface above the tunnel and was followed downward in a small steeply pitching shoot into the present ore body, where it expands into a sheet with the dip and strike of the surrounding gneisses. At the foot wall is a narrow seam of calcite that appears to be secondary as it sends veinlets into the contiguous ore and gneisses. In mass the ore appears distinctly schistose. On its borders are selvages of garnet and hornblende, several feet thick. Within these the ore is fairly uniform in character, varying only in the proportions of magnetite and carbonates present. Here and there near its edges are pockets of loose magnetite, especially near the foot wall, where the sparse carbonate cement in lenses of granular magnetite may have been dissolved by percolating water. The pyrite that has already been referred to is confined almost exclusively to the borders of the ore 148 Journal of the Mitchell Society [March body and to the vicinity of little veins of hornblende ciittino- thi-oiii-h it. It is apparently most abundant where shearing has taken place. From the main mass of the ore body the mineral is entirely absent, so that it has no bad effect upon the ore. Through the ore are small vein-like masses of coarse black hornblende or of hornblende and mag- netite all running parallel to the schistosity of the ore, which is paral- lel to the general strike of the ore body, thus accentuating the struc- ture. In some cases there are also present in the limestone streaks of magnetite that suggest very strongly little dikes. These are rarely more than ly^ inches wide. Their walls are nowhere sharp, but on the contrary on their margins the magnetite layers pass into the marble by gradations, the carbonate grains becoming more and more abundant toward the marble side of the contact until finally the rock becomes essentially a nearly pure marble. The thin section shows the magnetite streak to be an aggregate of carbonates, actinolite and mag- netite, with the last named of course predominating. The mine has been operating for only a short time. About 500 carloads of ore had been shipped to Aug., 1919. At present the ex- posed faces of ore suggest the existence of two sheets parallel to the foliation of the country rocks. The explorations are not sufficiently extended to show how far the sheets are continuous, consequently there is no means of estimating the magnitude of the, reserve. The lower sheet is believed to pinch out just beneath the floor of the tun- nel, as is indicated in the cross section on pi. 25, but its extension in other directions is entirely unknown. The upper sheet has been shown by a raise to extend from the tunnel level to near the surface but there is no evidence to show how far it extends beneath the tunnel or beyond the sides of the raise. Although the vein looks more regular at its present depth than it was nearer the surface, nevertheless there is no certainty that it will not suddenly become broken and irregular. Origin of the Ore : — If the theory' with regard to the origin of the Cranberry ore is correct, and the magnetite in this deposit is due to deposition from ascending hot liquids and gases brought upward by augitic pegmatites, then it se?ms probable that the marble ores are likewise the result of pegmatitic solutions. Old limestones were meta- morphosed by solutions depositing magnetite and producing horn- blende and aiding in the development of garnet and actinolite from ' Bavlev, W. S., The Magnptites of Xorth Oiirolina — Their Origin. Econ. Geol. v. IG, no. 2, March, 1921, j.p. 142152. 19^2] A Magnetite-Marble Ore at Lansing, N. C. 149 the constituents of the limestone. That the aetinolite is in more or less distinct lawyers may well be due to the presence of argillaceous lay- ers in the original limestone. The production of the aetinolite in part at least seems to have been subsequent to the deposition of the mag- netite, but that its production was promoted by pegmatite solutions seems to admit of little doubt. The distribution of the components of the ore is such as would occur if they were produced by pneumato- thermal contact action, emanating from dikes of pegmatite. No dis- tinct dikes of pegmatite are to be seen cutting the limestone ores, but they are believed to be represented by the small veins of quartz and epidote that traverse it, by the aggregates of epidote and magnetite and those of hornblende and magnetite that appear as streaks in it and by the lenses of dark hornblende that occur here and there. The epidote is believed to represent the feldspar of the pegmatites. All gradations between pegmatites in which the feldspar is only slightly epidotized and those in which all the feldspar has been replaced by epidote are common in the Cranberry area. At Lansing very little of the pegmatite magma reached the position of that portion of the ore body now being worked, but the gases and liquids travelled along the contacts between the limestone and the gneiss, penetrated the lime- stone near the contacts and caused the deposition of magnetite and the production of garnet which have been described as forming a sel- vage on the borders of the ore body. Siniilar Ores Elsewhere : — The only other point in the state at which similar magnetite-marble ore is known to exist is a few yards north of Dr. Jones's residence, about a third of a mile northeast of the rail- road station at Lansing and three-quarters of a mile north of Capt. Cooke's mine. Here a hole was put down at a place where there was much magnetite in the soil. At the depth of 25 feet a big piece of limestone was encountered in the midst of the gneisses, with man- ganese ore on opposite sides. The hole is now filled but on the old dump, w^hich has almost entirely disappeared, a fragment of antinolitic rock was found that is unquestionably a metamorphosed limestone consisting of calcite, aetinolite and tremolite. Since returning from the field the study of the specimens collected suggests that possibly the Red Rock ]\Iine about 11/2 miles southeast of Shell Creek in Carter County, Tenn., and one mile from the North Carolina State line is another similar deposit, but information of the 150 Journal of the Mitchell Society [March character of its ore is furnished only by the fragments on the dumps. Marhle in the pre-Camhrian near Toecane: — The rarity of marble- magnetite ores in western North Carolina may be due to the fact that the limestone beds themselves are rare. Their best known occurrence is in a cut on the C. C. & 0. R. R. at Intermont, which is about four miles south of Toecane in Mitchell County. The limestone is a coarse white marble associated with gneisses and pegmatite. It is mapped by Keith as being in the Carolina gneiss — a series of micaceous and gar- netiferous schists and micaceous, garnetiferous and cyanitic gneisses, which are believed to be the oldest rocks in the region. Keith^ de- scribes the marble as occurring in two bands alternating with mica- gneiss and dipping 50° S. E. The rocks are cut by a pegmatite vein, which passes in places across the beds and in other places along them. The upper layer is said to be 70 ft. thick and the lower layer 8 ft. with a 10 ft. thick layer of mica gneiss between them. The marble is white and coarsely cr.ystalline. It consists of 55% CaCOo and 45% MgCOg. The contacts of the marble with the contiguous gneiss are said to be sharp. Contacts with the pegmatite are equally sharp, but in some places between the marble and pegmatite is a thin contact vein of actinolite which grades into the marble. Inclosed in the lower marble is also a small mass of actinolite and serpentine. The marble is supposed to be a metamorphosed sediment interbedded with silicious sediments now represented by gneisses and schists. A sketch of the exposure is reproduced in pi. 27. Instead of being in two distinct layers as might be inferred from Keith's description the section now displayed on the railroad shows the marble to be in fragments separated by gneiss and pegmatite. It is possible that the three masses visible in the section may originally have been parts of a single bed or parts of two beds, but it is certain that their present distribution is due to fracturing and intrusion by pegmatite. At the south end of the section near its bottom the limestone is in contact with the pegmatite and with gneiss. For half an inch from the con- tact with the gneiss the limestone is bordered by a light gray zone in which are many plates of a light mica resembling phlogopite, a few plates of biotite and an occasional garnet. At the immediate contact is a seam of light brow^l mica. Under the microscope a section cut across the contact zone reveals the presence in it of many plates of an almost colorless mica with a 'Mount Mitchell Folio. Geol. Atlas of the U. S. Polio 124, p. 2-3, 1905. CM lA i 0-) fii i 1922] A Magnetite-Marble Ore at Lansing, N. C. 151 slight pleochroism in light yellow tones. These are arranged about parallel to the contact plane. A few crystals of pyrite are the only other components present except, of course, the predominant, com- paratively large grains of carbonate, most of which are polysynthet- ically twinned. The carbonate is free from inclusions except for tiny particles of what appears to be pyrite dust, but between the grains is often a stain of limonite. Immediately at the contact there had been slight movement with the development of a thin layer of light colored mica. At the contact with the pegmatite the contact zone is about 11/2 inches wide, and is composed of two layers, the inner one of which is characterized by the presence of plates of tremolite and more scanty plates of wollastonite scattered through the limestone, but mainly in such a way as to constitute bands running parallel to the contact. The tremolite is generally fresh and colorless but the wollastonite is traversed by many cracks in which have been deposited fibers of a light green micaceous mineral, with a slight pleochroism in greenish and yellowish tones. Occasional tremolite flakes are tinged with green. These are very slightly pleochroie, thus approaching actinolite in char- acter. The outer zone next to the pegmatite consists exclusively of a light-gray platy tremolite arranged with its long directions perpen- dicular to the contact. The tremolite strongly resembles the mineral at the Lansing Mine that has been called actinolite. Whether the two minerals are actually the same or are different is of little importance. Their presence indicates that the pegmatite added material to the limestone in both cases. The irregular distribution of the limestone, parts being almost completely surrounded by silicate rocks, suggests an explanation of the irregular distribution of the ore at Lansing. The limestone bed was broken into fragments as at the occurrence on the railroad and the limestone ore naturally possesses a similar dis- tribution. Reserves : — Because of the irregular manner of distribution of the limestone in the schists at the Lansing locality and the small amount of prospecting that has been done in the mine, it is impossible to esti- mate with any probability of correctness the quantity of ore that may be expected. If the limestone is shattered as it is near Toecane it may terminate within a few feet of the present workings, or it may extend beyond them for a long distance. In either event it is probable that 152 Journal of the Mitchell Society [March the limestone ore may be replaced by silicate ore such as was found in the old Wauphbank opening above the present mine, in which case it may be valuable or worthless, dependino- upon the width of the vein. The limestone ore is merchantable even when its iron content is as low as 35%. The silicate ore must carry much more iron l^efore it will be accepted at the furnace, and most of it therefore must be concen- trated. Urbana, III., July, 1921. A BOTANICAL BONANZA IN TUSCALOOSA COUNTY, ALABAMA By Eoland M. Harper Plate 28 Tuscaloosa, on the Warrior River, is one of the typical fall-line cities of the South. Above the city the river and all its tributaries, with a few exceptions, flow their whole length through the Warrior coal field, characterized by essentially horizontal strata of sandstone and shale, which make many picturesque bluffs and cliffs along the river, some of them over 150 feet high, interrupted every half mile or so by wooded ravines, containing small streams which may dry up in summer, and at longer intervals by creek valleys. A few tributaries take their rise in limestone vallej^s about 100 miles northeastward, but it is not likely that this fact has any perceptible bearing on the richness of the cliff flora to be discussed presently. Below Tuscaloosa the river cuts through Cretaceous and Eocene strata, with no cliffs of hard rock, and conditions are unfavorable for most of the plants herein mentioned.^ Above Tuscaloosa the river runs in a general southwesterly direct- ion, so that the left bank is usually shaded, the bluffs on that side facing in various directions between north and west. On this left side a few miles above the city there is a remarkable assemblage of rare and otherwise interesting plants, on exposed cliffs and shaded bluffs and in nearbj" ravines. For some unknown reason, the greatest con- centration of rarities seems to be about eight miles above the city, their numbers diminishing up and down stream from that point. They gradually disappear also away from the river, as one ascends any of the tributary creeks. The writer has had few o])portunities to explore the right bank, wliich is relatively inacessible, but as most of the bluffs on that side are exposed to the sun in the middle of the day, the shade- loving plants listed below can hardly be expected to thrive there. At Squaw Shoals, about thirty miles above Tuscaloosa, there were many interesting aquatic plants in the rocky bed of the river until they were drowned out by the completion of a 63-foot dam in 1915-, but apparently no cliff plants of special interest, except Ileuchera * For an afcount of tho river-bank vegetation for a distance of about 250 miles below Tuscaloosa see Bull. Torrey Bot. Club 37:107-126. 1910. ^ See Torrrya 14:149-155. 1914; Natural History 19:199-201. 1919. [1531 154 Journal of the Mitchell Society [March macrorhiza. And quite i-ecently (Ma}-, 1921) the writer has traversed over 100 miles of the river above Tuscaloosa in a canoe, with frequent landings, without materially extending the known distribution of any of the plants mentioned below, not even those which have their southernmost outposts near the fall line. Before listing the rare plants some additional features of the en- vironment may be mentioned. At the point where they are most num- erous and for a few miles farther upstream, the hilltops are capped with sand and pebbles of Cretaceous or later age, belonging to the coastal plain, and characterized by forests of Pinvs pahistris and its common associates, subject to frequent fires, as is usual throughout the range of that tree. In the same neighborhood the lowlands on the inner sides of bends are covered with ''second bottom" or terrace de- posits, which extend all the way to the coast but are very slightly represented upstream; and ^Acer saccharinum (formerly A. dasycar- puni), which is perhaps more nearly confined to river-banks than any other tree in the eastern United States, and seems to require twenty feet or more of seasonal fluctuation of water, extends up the river just about to the point under consideration. Quercus laurifolia, which is almost confined to the coastal plain, extends a few miles farther upstream. But all this perhaps has as little to do with the peculiarities of the cliff flora as the fact that some of the river water comes from a limestone valley. It may be a little more significant that there are among these cliffs several ' ' hanging valle.ys, ' ' with mouths high above the river, presumably indicating that the streams which made them are dry most of the time, and therefore have not cut down their chan- nels as fast as the river has. Springs too are scarce along the river, as the canoeist discovers to his discomfort in hot weather. This indi- cates that there must be little leaching out of the elements of fertility from the rocks. Some of the plants under consideration are of species commonly supposed to be partial to limestone, although the rock is not notice- ably calcareous. A partial analysis of a specimen of the shale made for the writer some years ago showed only 0.42% of lime (CaO), but nearly ten times as much potash (K^,0), namely, 3.95%^; and it is quite likely that these and many other supposed calciphiles are really See Geol. Surv. Ala. Monog. 8: 54. 1913. PLATE 28 Kieli ravine near Warrior Iviver a little below month of Hurricane Creek, with Ai in full bloom, and trunk of Uquidamhuv at right. June 28, 1911. ■('/»*■ jjarviflora Looking down Hanging Valley on lell and 100 feet above the water. N'lev, lake Pinus Virginiaria. Dec. 2, 1911. li;iiik of W.iiTior Iv'ivrr .-iIkmiI niiir niilc^ alxive Tu; iImmiI :s, Liriodendron, Liquidamhar, Pinus Taeda, Quercus aiha, Cercis, Ilex opaca, Ostrya, Aesculus Pavia, Bignonia, Aralia spinosa, Hypericum aureum, Adelia ligitistrina, Ptelea, and even Croomia and \Alsine puhera. And the two endemic trees of the Florida bluffs (representing two genera of Taxaceae) are no more remarkable 'than the shrubs Croton ^lahamensis and Neviusia, which are not known outside of Alabama. (The former is known from two counties and the latter from three.) It is rather singular that the Croomia, unlike nearly all the other species listed, has its northernmost known limit in the area under discussion. Unfortunately civilization is making inroads on these bluffs and ravines, as on many other beauty spots the world over. The smoke "See Bull. Torrev Bot. Club 31:26. 1904. '2 See Torrey 19:119-122. 1919. 4 160 Journal of the Mitchell Society [3Iarch from the trains that pass four or five times a clay does not benefit the cliff vegetation any, and whenever a new coal mine is opened or a sawmill located near the river, houses are built nearby, necessitating clearing away some of the forest. The best long-leaf pines on the adjacent hills were cut by lumbermen about seven years ago, and in some places the logs are rolled down the bluffs to the river or some creek, necessitating cutting a swath through the vegetation. A de- velopment which may be looked for almost any day is the building of summer homes on the bluffs by some of Tuscaloosa's ''idle rich," with a consequent scattering of tin cans and other rubbish in the adjacent ravines. But at any rate, the topography is so broken that little of the area is likely to be molested in the near future by farmers, and there will probably be some interesting vegetation there to study Lor a generation or two yet. FISHES IN RELATION TO MOSQUITO CONTROL By Samuel F. Hildebrand It lias been known for many years that varions species of fishes prevented mosquito production when placed in small inelosures, such as cisterns, fountains and pools, but only comparatively recent studies and experiments have led to a fairly definite determination of the species and the conditions most favorable for mosquito control in larger bodies of water. Some of the species which are used for mos- quito control in small artificial waters are wholly unreliable in large bodies of water where a greater variety of foods is available, showing that in confinement fish take foods which ordinarily are not eaten. The variegated minnow {Cyprinodon variegah(s) , a strictly herbaceous fish, for example, may be confined in an aquarium and fed on a diet of wiggle tails and minced beef or fish and kept alive for several months. It may also be placed in a pool comparatively free from vege- tation, but infested with mosquito larvas, and it will live indefinitely and provide mosquito control. Experiments and observations relative to Mollienisia latipinna^ a minnow structurally rather close to Gam- husia affinis and usually found with the latter in great abundance in potential mosquito breeding areas in the lowland swamps and slug- gish ditches of our coastal plains from Soutli, Carolina to Mexico, have led to the conclusion, however, that the food of this species con- sists almost wholly of plants and that it is worthless as an agent for the control of mosquito production. It, therefore, is necessary, for the purpose of mosquito contriU in nature, to find fishes that not only choose a habitat suitable for mos- quito production but which by preference feed upon live animals. They also must seek "bait" of the proper size and thej^ furthermore must feed at the surface, for that is where the mosquito spends most of its life in the aquatic stages. It likewise is very desirable to use a fish which will reproduce under a wide range of conditions, i. e., in almost any water in which mosquitoes breed, also one which multiplies very rapidly. Ganibusia affinis, a species in which the female reaches a maximum length of about 60 mm. (2% in.), the male being much smaller, very admirably meets all of the requirements mentioned in the preceding paragraph. It is common almost everywhere throughout the mala- [161] 162 Journal of the Mitchell Society [Ma)'ch rious sections of tlie Soutli where it inliabits i)()tential inosqiiito-hreed- iiig areas. It is not limited for food entirely to live animals, but it undoubtedly prefers that kind of a diet, and a wiggle tail certainly is a "bait" of suitable size for this fish and one which appears to "tickle the palate." The habit of surface swimming which is corre- lated with surface feeding in Gamhusia is highly developed, the fish having received its common name, "Top Minnow," because of its almost constant appearance at the surface of the water. Gamtiisia is viviparous, i. e., the eggs are fertilized and hatched within the body of the parent fish, and the young when born are from 8 to 10 mm. (-^g to % in.^ long and come into the world well developed, being much better able to take care of themselves than most fishes hatched from eggs in the more usual way. This fish, unlike most others, therefore, requires no special environment for depositing and hatching eggs, the young being born as the female moves about in the water. The species, for this reason, is able to reproduce under a very wide range of conditions. The young come in broods, numbering from a few to one hundred or more, throughout the summer and at intervals of from three to several weeks each. The young when born are so well developed and so thoroughly capable of beginning an inde- pendent existence that their chances for survival are excellent. They grow rapidl^^ and the early broods of the season become sexually ma- ture and themselves have young before the end of the summer during which they are born. Multiplication therefore is very rapid. Gamhusia, as already indicated, is common in most of the mala- rious sections of the South and in many localities it has become dis- tributed to the sluggish ditches and standing bodies of water, as far as natural waterways have from time to time been open. In other localities the fish is not so universally distributed and in nearly every vicinity there are present some waters which the fish is unable to reach because there are no channels connecting them with other bodies of water. It is here where aid in distribution by man is needed. It is not claimed that Gamhushi, when present in a body of water, will eliminate all mosquito production under all conditions. Some- times, when conditions are proper and sufficient top minnows are present, mosquito production is completely eliminated. In many cases it is not eliminated but very greatly reduced. The value of Gamhusia as an eradicator of the immature mosquito 1922] Fishes in Relation to Mosquito Control 163 may be determined by the inspection and eomi)arison of quiet waters which support top minnows with those in the same locality which do not support top minnows, in order to determine which waters produce the most mosquitoes. Ponds heavily infested with mosquito larvae and pupae may be stocked with Gamhusia and results awaited and observed. One of two similar, neighboring bodies of water both infested with immature mosquito, may be stocked with Gamhusia. The water which is not stocked with top minnows will serve as a ''control" which will furnish a fair comparison. Occasionally it is possible to demonstrate the destruction of mosquito larvae which Gamhusia accomplishes by connecting by means of a ditch one pond or pool heavily infested with mosquito larvffi with another sup- porting top minncws. All of the foregoing experiments and obser- vations have been made within recent years and in every instance either a great reduction in mosquito production resulted or, as in man,y cases, complete control followed. Wherever mosquito produc- tion was not eliminated, if sufficient minnows were used, complete con- trol was prevented by the presence of places of protection for the immature mosquito against fish. Places of refuge for mosquito larvae and pupae in the presence of fish are furnished by such types of plants and floatage which are slightl}' or partly submerged, causing a mere film of water to stand above them. Anopheles larvae are particularly keen in seeking these places of refuge where they cannot be reached by the minnows. The low aquatic grasses, particularly Hijdrochloa carolinensis, are a source cf much difficulty in securing mosquito control by the use of fish. Mats of floating algffi with a film of water over them also form excellent hiding places for the immature mosquito. ]\Iany other plants, some of them strictly aquatic, others of the shore variety, often cause imperfect control when they are partly or slightly submerged. Plants which are wholly submerged do not appear to hinder mosquito control by the use of fish. Certain plants, such as the floating prim- rose willows and the tall wire grasses, sometimes develop dense masses of roots near the surface of the water wliich provide a limited amount of protection. The tall plants with straight stalks and with few or no leaves, and without dense roots near the surface, like the cat-tails, the rushes, etc., provide little or no protection for mosciuito larvae and pupte. The duck weeds not only furnish no refuge but whenever 164 Journal of the Mitchell Society [March a pond is largely covered with them they appear to prevent mosquito production. The leaves of these plants are wholly above the surface of the water, they do not have a dense root system, and furthermore it is possible that the more or less constant shifting of the weed masses with the winds or currents may drown the eggs. Since there are many conditions under which plants furnish pro- tection for the immature mosquito against fish, it is very essential in the conduct of anti-malaria campaigns to make frequent and careful inspections of all waters in the area under control. If it is found that certain plants are preventing mosquito control, then it is time to aid the minnows. The indiscriminate cutting and clearing of vegetation from water deposits certainly is not an economical practice, as such work frequently is not necessary. The biological condition existing in each pond must determine whether or not top minnows will require assistance from man to furnish control of mosquito production. The abundance of top minnows must be carefully considered, and certainly the amount of food available for them in each body of water is of great importance. The writer has shown by experiment that when food is scarce better mosquito control will result than when it is plen- tiful even though much vegetatioji of the "protective tj^pe" is present, and he knows of no other way to explain why mosquito production in certain ponds is much more nearly eliminated than in others when minnows and plants appear to be identical and present in equal abun- dance. It is evident then that top minnows are of much value in control- ling mosquito production in permanent standing bodies of water and that they also render excellent service in sluggish ditches. Their value as eradicators of mosquito larvae has been recognized by health officers, and minnows are used very widely in the South where anti-malaria campaigns are conducted, having in a large measure replaced the use of oil. A definite use for oil in anti-malaria work remains; for places exist in nearl}' every locality where mosquitoes breed and where fish cannot be used, as, for example, in a film of seepage water, iix lioof prints, in temporary pools, etc. It is well known that in order to secure mosquito control by the use of oil a continuous film must cover the entire surface of the water and that during hot weather a new coat of oil must be applied about once a week. It is quite impossible to obtain a continuous film on ponds and lakes, because the oil is 1922] Fishes in Relation to Mosquito Control 165 driven to one side or to a corner, leaving the remainder of the water exposed. Furthermore, if oiling is discontinued after it has been ap- plied for some time, the natural enemies of the mosquito have usually either been driven away or killed and thereafter the mosquitoes can reproduce more successfully than before the natural conditions were disturbed. Since fish control is much more permanent in its results and much less expensive, it seems advisable to use fish wherever pos- sible and to apply the oil treatment only where fish cannot be suc- cessfully used. Drainage undoubtedlj" deserves first place among the measures of mosquito control because of its permanent character, but it is a recog- nized fact that all water deposits cannot be eliminated and further- more, it is undesirable to eliminate all of them. The cost of drainage usually is high and therefore often prohibitive. Fish control can usually be substituted in part for drainage, and is especially recom- mended for rural sections and for other localities where funds for the more expensive measure are not available. A number of species of fishes besides Gamhusia affinis have been recommended for mosquito control, but none has been as extensively used as Gamhusia. Only one other species in the South, viz., Heter- andria formosa, a viviparous species, belonging to the same family as Gamhusia, but of much more limited distribution, ranging from North Carolina to Florida, has given results comparable with those obtained with GamhiLsia. Several species of the genus Fundulus, also belonging to the top minnow family, probably are of limited value. Some of the sunfishes have been mentioned in connection with mos- quito control, but their usefulness in the South is not well established. They certainly are much less efficient than Gamhusia. Gamhusia affinis, as already noted, is common almost everywhere throughout the malarious sections of the South. What the conditions without these faithful servants would be is difficult to conceive, but it is quite probable that sections which are prosperous would be in a very backward state and that others would be entirely undeveloped. Doctor H. R. Carter, assistant surgeon general, U. S. Public Health Service, who is well qualified to speak as an authority on the subject, positively asserts* that prosperity is not compatible with the preva- lence of malaria and he declares that no prosperous community exists * Public Health Bulletin, U. S. Public Service, No. 105 ; 40. 1920. 166 Journal of the JMitchell Society [M'arch where malaria seriously prevails. If a community cannot prosper when malaria prevails, the importance of com])attin<>' such a disease bj^ every known means is evident. The use of top minnows for this purpose, although comparatively new, as alread}' stated, has been adopted by many health officers in nearly all of the southern states wherever practical anti-malaria work is being- conducted. ]\Iueh wider use, however, should be made of this comparatively inexpensive agent. Nature has been kind in the distribution of the top minnow, as al- readj^ shown, but still natural bodies of water remain in some local- ities which have not become stocked with Gamhusia. The artificial waters usuall}^ are inaccessable to the minnows and, since they nearly always are near residences, it is especially important to prevent mos- quito production in them. Certainly much good can be accomplished by the judicious distribution of the top minnow, and the results will be doubly effective if it is given aid by clearing vegetation from the water wherever necessary. Bureau of Fisheries, Washington, D. C. NOTES ON THE MORPHOLOGY AND SYSTEMATIC RELA- TIONSHIP OF SCLEROTIUM EOLFSII SACC* By B. B. Higgins Plate 29 In spite of the proved parasitism and general occurrence of Scle- rotium rolfsii in the warmer portions of the United States, very little is known in regard to the structure cf the mycelium and of the scle- rotia of the fungus. The few data that have been published on the subject have contained so many errors as to be confusing rather than clarifying. It, therefore, seems desirable to pul^lish, at this time, a few notes that may be helpful to others who come into contact with this fungus. The reputed appearance and disappearence of the fungus in fields, and its other peculiarities, have led to investigations with the hope that some fruiting stage would be discovered. So far no spores have been found ; but certain characteristics of the mycelium have been noted, which are of considerable help in distinguishing the mycelium of this fungus from that of several others that attack plants in a somewhat similar manner. These characters also suggest, in a general way, the spore forms that one should expect to find associated with this myce- lium. On fleshy plants and on fruits, such as cantaloupe, where food and moisture are abundantly available, the growth of S. rolfsii is very vigorous and characteristic. The mycelium usually forms broad white sheets and a profusion of sclerotia develops ; but on small or more woody stems, such as those of sweet potato slips or of pepper plants, the growth is often very scanty and impossible to distinguish macro- scopically from any one of several other fungi that may attack these plants. Even when such plants are placed in a moist chamber, scle- rotia often fail to develop. MYCELIUM The mycelium is rather coarse, with large cells (2-9 x 150-250/*). The feeding branches which enter the medium or the host tissue and those which enter into the formation of the sclerotia are of the more slender type (about 2/x, in diameter). In the broader threads clamp connections occur characteristically, two at each division (figs. Pjiper nunibpr 15, Journal Series, Georffiu AKricultural Experiment Station. [167] 168 Journal of the Mitchell Society [3Iarch 5-8). Often, however, a branch arises just back of the cross wall in the place of one of the clamp connections (fig. 6). In the larger threads this is the only type of branching that is at all common ; but from the more slender threads clamp connections are often wanting and branches may arise from any point, without regard to the cross wall. The clamp connections often develop abnormally, extending the full length of the cell (fig. 7) or even joining a neighboring hypha or a branch with the main hypha (fig. 8). The peculiar appearance of these clamp connections is evidently M^hat gave Taubenhaus* the im- pression of budding in the mycelium. The branches, especially those of the more slender type, often an- astomose (fig. 10) and hold the hyphs together in sheets or occa- sionall}^ in strands. The cells of the mj'celium are binucleate, at least when young. SCLEROTIA The sclerotia first appear as small white tufts of loosely inter- twined small branches (fig. 1). Stained sections of such tufts show an actively growing region near the periphery, which is about %o of a millimeter thick, rich in protoplasm, and showing a much greater affinity for stains than the center of the mass or the looser downy covering which surrounds the growing region. Within a very short time, 24 to 48 hours in rapidly growing material, all the cells of the mass, except those of the downy covering, begin to enlarge (fig. 2) and swell to about three times their former size. At the same time they become vacuolate and, usually, multinucleate. The cell walls of the cells in the growing region seem to gelatinize and coalesce, form- ing a pseudo-parenchymatous tissue (fig. 2) about Yj millimeter thick. The cells of an outer la^^er, two or three cells tliiek, now lose their protoplasm ; and the cell walls turn dark, collapse to a certain extent, and form a corky appearing covering over the entire surface of tlie now mature sclerotium (fig, 3). The outer downy covering has be- come separated by the formation of this ccrtical layer and it now sloughs off, leaving the surface dark brown, smooth, and somewhat shiny. The cells of the pseudo-parenchyma are broad, and more or less angled, with thick colorless walls and no air spaces between; * Taubenhaus, J. J. Recent Studies on Sclerotium rolfsii Sacc. Jour. Agr. Res. 18: 127. dIs. 3-6, fie. 1. 1919. 1922] Notes on Sclerotium Rolfsii Sacc. 169 while those of the center of the sclerotium retain their hyphal char- acter and are separated by large air spaces (fig. -1). The mature sclerotia are dark brown in color, globose to elliptical, and I/2 to 11/2 millimeters in diameter. Taubenhaus* suggests the existence of plus and minus strains of the fungus and the necessity of a "sexual act" in the formation of the ^:clerotia. If proved, this would indeed be an interesting con- dition, entirely new among fungi, and well worthy of serious study. The absence of any spore form made the task of separating pure strains for the study unusually difficulty If an ordinary branched filament were used, one could hardly be positive that parts of other filaments were not included as anastomosed branches. In pursuance of the plan finally hit upon several sclerotia from an old culture, obtained originally from a wilted pepper plant, were planted on agar plates which were then inverted and placed in a cul- ture room until considerable aerial growth had formed under the sclerotium. A few filaments from this growth were picked up on the point of a flamed needle which was then dragged across a sterile agar plate. The plate was then inverted on the stage of the microscope ; and, with the low power objective, single unbranched threads were located and their position indicated bj' ink marks on the bottom of the plate. Blocks of the agar, each containing a single thread, were then cut out with a flamed scalpel and transferred to another plate of sterile agar. In this way fifty short filaments were isolated and planted. The plates were placed in an incubator and examined under the micro- scope at least once every twenty-four hours for evidence of growth or of contamination. Most of the number either died or showed con- tamination within a few days, but five lived and produced new growth. In these five cases the torn ends of the threads died and the new growth developed from two or three cells remaining alive in the center. After growth was well started all five were transferred to tubes of steamed bean pods where, after a few days, each had produced sclerotia in great abundance. Transfers were then planted on plates of peptone beef extract agar — three colonies to each plate, two of A and one of B, etc., throughout the series; so that colonies of each strain Taubenhaus, .7. J. 1. c. v. 136. 170 Journal of the Mitchell Society [March would come into contact with colonies of the same strain and of eaeli of the other four strains. The production of sclerotia was so:newhat irregular in these plates, but no sign of "mixing" was noted. Sometimes they were most abundant where two colonies, either of the same or of different strains, met ; but this was not at all constant. Often they began developing abundantly at the center of the colony before it had come in contact with the other colonies on the plate. The most abundant develop- ment noted in any case was found where a colony of bacteria was over- grown by the fungus. The variation seemed to be due to irregular food supply and to any irregularity in the surface of the medium which increased the aerial growth of the mycelium. While this experiment does not prove the non-existence of plus and minus strains, it does show that mixing of such strains is not necessary for the production of sclerotia. germination op the sclerotia When mature sclerotia are placed in contact with a suitable me- dium they send out hyphfe from all over the surface without forming any apparent break or crack in the tissues. Each thread arises and pushes out to the surface separately. In new sclerotia such new growth may, probably, arise from any living cell; but in very old sclerotia the cells of the pseudo-parenchyma appear to be dead, and the new growth arises from the cells of the more loose hyphal weft in the center (fig. 4). The new hyphffi are slender and pass lietween the old cells and finall.y pusli or dissolve an opening lietween the cells of the compact outer tissues. The cells of the new hyphse are ])inucleate. Whether they arise only from cells that have remained binucleate, or otherwise, has not been determined. longevity op the sclerotia If kept dry, the sclerotia remain viable for a long time. Some produced in cultures and kept in the culture tubes grew off readily when they were finally transferred to fresh media, when more than two years old. It is not likely that they last very long in contact with moist soil under field conditions. They seem to be very suscep- tible to freezing when wet. 1922] Notes on Sclerotium Rolfsii Sacc. 171 systematic relationship The presence of clamp connections and of the binucleate condition in the mycelium shows the relation of the fungus to the Basidwmij- cetes; but these characters are common to practically all the families of this group. Sclerotia are also produced by members of nearly all families of Basidiomycetes. It does not seem possible, therefore, to determine with certainty any closer relationship until spore formation has been observed. SUMMARY 1. The presence of clamp connections and a peculiar method of branching is a valuable aid in distinguishing the mycelium of 8. rolfsii from that of other fungi producing similar lesions on plants 2. The affinity of S. rolfsii to the class Basidiomycetes is indicated by the septate, binucleate mycelium and by the presence of clamp connections at the septa. 3. The mixing of plus and minus strains is not necessary for the production of sclerotia. Experiment, Ga. Explanation of Plate 29 Fig. 1. Part of a sector from section of a very young sclerotium of S. rolfsii, showing interwining of the slender hyphfe; a, the loose hairy covering; b, darker stained growing region; and c, paler hyphae in the center of the weft. X 367. Fig. 2. Part of a sector from section of a slightly older sclerotium; a, the loose hyphal covering of the sclerotium; b, the pseudo-parenchyma with its large cells and thick colorless walls; and e, looser growth and large air spaces in the center of the sclerotium. x 367. Fig. 3. Portion of the outer tissues from a section of a mature sclerotium ; a, remains of the loose hyphal coverings, partly dead and sloughing off; b, pseudo-parenchyma, the outer layers of which have formed the brown cor- tical coverings, x 367. Fig. 4. Section from near the center of a germinating sclerotium, showing two slender new hyphae (d) pushing between the partly dead cells of the sclerotial tissue ; from a scerotium more than a year old. x 367. Fig. 5. Septum and double clamp connections in vegetative mycelium of S. rolfsii. X 154. Fig. 6. Portion of a hypha in which a branch lias grown out in the place of one of the clamp connections, x 154. 172 Journal of the Mitchell Society [March Fig. 7. An abnormality in which the branch taking the place of a clamp con- nection has grown out and connected Avith the second cell beyond its place of origin, x 154. Fig. 8. Another common abnormality in which the clamp connection growing out from a branch connects with the mother hypha. x 154. Fig. 9. Hypha of the more slender type with a l>ranch arising from near the center of a cell, x 154. Fig. 10. Anastomosing branches in the vegetative mycelium, x 154. All drawings made with the aid of a camera lucida. AN INTERESTING ANOMALY IN THE PULMONARY VEINS OF MAN By W. C. George Plates 30 and 31 Anomalies in the venous system are so common that most of them arouse no very great interest in the anatomist. One of the anomalies (pi. 30, fio'. A) found last spring in the anatomical laboratory at Chapel Hill and called to my attention by Dr. C. S. Mangum is so unusual and of such embryological interest as to seem worthy of a brief report. In this ca^e the blood from the upper left lobe of the lung was drained not into the atrium but into the systemic circulation. A fairly large vein, about one-half inch in diameter, emerged from near the middle of the ventral surface of the upper left lobe of the lung and coursed directly cephalad to empty into the left innominate vein about two and one-half inches lateral to the union of the two innominates to form the superior vena cava. The right pulmonary veins and the pulmonary vein from the lower left lobe communicate with the left atrium as usual. Somewhat similar connections between the veins of the pulmonary and systemic circulations have been recorded previously. With ref- erence to this sort of anomaly Bailey and Miller (1) make the state- ment that "The upper (more cephalic) [pulmonary] vein on the right side may open into the superior vena cava; or the upper vein on the left side may open into the left innomonate vein. A possible explana- tion of this is that the pulmonarj^ veins are formed after the heart and other vessels have developed to a considerable degree, and some of them may unite with the other vessels instead of with the atriiun. ' ' This explanation is apparently based on an erroneous conception of the pulmonary veins being sprouts that grow out from the sinus ven- osus into the lungs, and does not seem to be a satisfactory explanation in view of the relations existing between the pulmonary and bron- chial veins in the adult and their embryonic origin as shown by Alfred Brown (2). Brown has shown that the pulmonary system in the cat arises from an indifferent splanchnic plexus in the region of the lung bud (pi. 31, fig. C). This plexus communicates on the one hand with the sinus venosus and on the other with the neighboring sys- temic veins (cardinals, segmentals, et al.). This plexus around the lung bud differentiates into two systems, the pulmonary and the bronchial. In the adult the lungs receive their blood supply from two sources, [173] 174 Journal of the ^Mitchell Society [3Iar('h the pulmonary arteries from the right ventricle and the bronchial arteries from the aorta. Typically" the pulmonary veins drain the lungs of the blood brought in by the pulmonary arteries and, through connecting capillaries, a small amount of the blood brought in by the bronchial arteries reaches the pulmonary veins. Most of the blood brought in by the bronchial arteries, however, is carried away from the capillary plexuses around the ])ronehi l)y small bronchial veins which empt.y into the azygos and accessory hemi-azygos veins, repre- sentatives of persisting portions of the embryonic cardinals. Condi- tions similar to that shown in the anomaly that I have cited appar- ently arise as a result of some interference with the return of the blood through the pulmonary portion of the embryonic splanchnic plexus, thus causing both pulmonary and bronchial blood to enter the bronchial veins and resulting according to the laws of Thoma (3) in the enlargement of the bronchial system and an atrophy and dis- appearance of that part of the splanchnic plexus which would have formed the left pulmonary vein. Laws of Thoma (4) : (1) An acceleration of the current leads to an enlargement of the lumen of a vessel, and a slowing of the current leads to its narrowing and final disappearance. (2) An increase in the blood pressure is the cause for new formation of capillaries. (3) The growth in thickness of the vessel wall depends on the tension of the wall, which in turn is dependent upon the blood pressure and the diameter of the vessel. In this particular case then the large vein passing from the upper left lobe of the lung to the left innominate vein would be composed of the left bronchial vein and that portion of the accessory hemi- azygos between the innominate and the junction of the bronchial with the accessory hemi-azygos. On account of the great enlargement of this vein the distal portion of the accessory hemi-azygos appears as a side branch of the "anomalous pulmonary." Chapel Hill, N. C. LITEEATURE CITED (1) Bailey and Miller: Text-book of Embryology, p. 258, 4th ed., 1921. (2) Alfred Brown: The Development of the Pulmonary Veins in the Domes- tic Cat. Anat. Record 7:299. 1913. (3) R. Thoma: rntersuchungen ueher die Histogenese und Histomechanik des Gefiiss-systems. 8. 1-91. Stuttgart, 1893. (4) Quoted from Keibel and Mall's Textbook of Embryology 2:421. 112. o CO ^ W oc H < J Ph i ^ ^^1^ c3 ;s (S " ?3 j2. ^H 1> C3 2 > O ? S 3 rl o "o >. u S s ~ T5 G t 7i C3 g ■6 o J2 6 X > 5 ■5 s u _s C3 S" (D 03 tl o U ^ O a u "^ *' .S C3 1) < M C d C O hH c S Vi O >^ ^ bD .2"^ 3 o "^ S h i; p. =! _^ m-a C3 ^^^ ■^ V o M s .S ■H s '? S^ g o c C3 "7 1 o 0) y X B E C -< rS M„ ■^ :i s6S Q « -I c8 Sao * "3 11 -o p. > O a p. 0ji o H ^1 ^35. cs — t; H ~ o o "3 • r^ 1- s ^ 5'" " 2og ;i2 5-c THE EASTERN SHRUBBY SPECIES OF ROBINIA By W. W. Ashe The eastern shrubby species of Robinia are separated from Roi- inia pseudo-acacia L. (which has a smooth flat pod and white fragrant flowers) by having pods prickly, hispid, bristly or glandular and pink or purplish flowers. Key to Eastern Shrubby Species of Robinia Al. = alleghanian ; C. = Carolinian. Au. = austroriparian. TAvigs, petioles and pedicels viscid, pod flat; margined (Al. and C). Twigs (often petioles, etc.) covered with viscid secretion.... (1) R. viscosa Vent. Twigs (often petioles, etc.) with short gland-tipped viscid bristles (2) B. viscosa var. hardwegii (Koeh.) Ashe Twigs never viscid. Peduncles, twigs and shoots not hispid, rarely hispidulose. Leaves, twigs and peduncles eventually glabrous or nearly so. Flowers rose-purple, never fragrant ; pods thick. Flowers about 15 mm. long, leaflets lance ovate (Al.) (3) B. Icelseyi Cr. Flowers more than 17 mm. long, leaflets elliptic (Al.) (4) B. hoyntonii Ashe Flowers pale lilac or pinkish, fragrant; pods flat (Au.) (5) B. murgaretta Ashe Leaves and inflorescence canescent (Au.) (6) B. elliottii (Chapm.) Ashe Peduncles and vigorous shoots usually hispid (in 8 sometimes pubescent), pods thick. Flowers more than 20 mm. long, racemes few-flowered (Al.) TwigS densely hispid (7) B. hispida L. Tvidgs sparingly hispid, often merely appressed pubescent. (8) i?. grandiflora Ashe Flowers less than 20 mm. long, twigs never densely bristly Bristles on twigs short, gland-tipped; 6-18 flowered (C.) (9) B. longiloha Ashe Twigs usually glabrate; racemes 3-6 flowered (Au. & C.) (10) B. nana (Ell.) Spach. R. viscosa var. hardwegii (Koeh.) n. c. — R. hardwegii Koeh. This plant is frequent around Highlands, North Carolina, associ- ated with the form which has viscid twigs. A few short gland- tipped hairs are to be found on nearly every plant with viscid secre- tion and as the pubescence becomes more dense there seems to be less of the viscid secretion, so that the form with the viscid secretion gradually passes into the form having viscid pubescence. [175] 176 Journal of the Mitchell Society [March Robinia margaretta sp. nov. yA. shrub sometimes propagating by root suckers as well as by seed, 1-1.4 m. in height or in cultivation becoming 3 m. high and with a single tree-like stem. Leaves, with linear acuminate herbaceous stip- ules, rarely wdth slender thorns, formed of 15 to 19 (to 23 in cul- tivation), elliptical rather thick firm leaflets, rounded or subcordate at base and rounded or refuse at the mucronate apex, green and some- times appressed canescent as they unfold, becoming essentially glab- rous with age, rachis sparingly hispidulose, petiolule 2-3 mm. long, canescent. Twigs slender glabrous or hispidulose, tan or light chest- nut. Racemes spreading 7-13 flowered ; flowers faintly fragrant, pale lilac or with the vexellum slightly pinkish, and with a yellowish spot in the center, often with nearly white edges, 16-20 mm. long, the short broad calyx 7-10 mm. long, minutely glandular puberulent, the lobes abruptly acute about two-thirds the length of the tube ; pedicels 8-10 mm. long, puberulent and sparingly glandular hispidulose as well as the peduncles. The fruit in spreading clusters of 3-7, is linear 7-10 cm. long and about 1 cm. wide, tipped by the slender curved style, very thin and sparingly hispid with short spreading bristles. Common on sand hills around Augusta, Ga., growing with longleaf pine and Carya pallida var. arenicola Ashe and near Greenwood, S. C., on red clay uplands with rosemary pine, southern red oak, and white hickory. A specimen from the latter place was cultivated at Washington for five years, fruiting freely, and stock from it distributed. In its small pale fragrant flowers, long racemes, flat pods, and numerous leaflets, this plant is allied to R. pseudo-acacia. It is possible that Tab. 19, Abbott's Insects of Georgia, is intended to represent this species. Robinia grandiflora sp. nov. B. Hispida var. rosea Pursh, Fl. Am. Sept, (1814). Not R. rosea Loisel in Duham. Arb. Ed. nov. t 17. A slender shrub 1-3 mih. in height or in cultivation reaching 5 m., propagating extensively by root suckers as well as by seeds. Shoots and twigs mostly soft appressed silky pubescent or also sparingly setulose with weak spreading pale colored bristles ; or vigorous shoots densely hispid near the tips. Leaves 15-30 cm. long, the rachis mostly appressed pubescent, at least when young; leaflets 9-13 (to 17 in cultivation), broadly elliptic or broadlj' ovate 4-6 cm. long, mostly rounded at both ends and tipped with a very short mucro, bronze on 1922] The Eastern Shrubby Species of Robinia 177 the upper surface and white satiny canescent on the lower surface as they unfold and permanently more or less appressed pubescent. Ra- cemes 6-9 cm. long, 3-7 flowered; flowers large 20-23 mm. long, rose- purple or purple and white with a large pale spot on the vexellum; the calyx 12-15 mm. long, the lobes, gradually acuminate and much longer than the tube, purplish or whitish silky canescent, as well as the pedicels or often with short weak bristles intermixed. The fruit mostly solitary at the ends of the short pubescent and often some- what hispid peduncles is dark brown, 4.5-6.5 cm. long, tipped by the stout slightly curved style, the slightly margined body about 1 cm., wide and rough bristly where distended by tlie seeds, but the intervals often much constricted and nearly free from bristles. This plant was first collected by me on the south slopes of Grand- father Mountain in 1900 and a seed-bearing plant which attained a height of more than 4.5 m. was cultivated for many years. An in- fertile plant less hispid and more pubescent, the stock of which was collected by me on Grandmother Mountain, in 1915, has been in cul- tivation since that date and numerous plants from it distributed. This species is evidently closely related to R. hispida L., but is readily separated by its larger size, by its pubescence, paler flowers and the fact that it is less hispid. Type, W. W. A., Grandfather Mountain, N. C, July, 1900. Many plants of this species, of R. hispida and of R. longiloha, although having perfect flowers do not set fruit. Meehan apparently first called attention to this in the case of R. hispida in cultivation. Large patches of R. longiloha have been examined, all evidently from the same stock by vegetative propagation without signs of fruit — and it is possible that certain patches may not fruit, just as the plant of R. grandiflora which I now have in cultivation has never set fruit — but this I have attributed possibly to the lack of cross fertilization. T have recently obtained fruit of what seems to be typical hispida and have a plant from the seed now growing. Forest Service, Washington, D. C. A NEW OAK FROM THE GULF STATES By W. D. Sterrett There was recently brought to my attention by W. W. Ashe, of the U. S. Forest Service, material of an oak he collected in Louisiana and eastern Texas, and which he seemed to regard as possibly an unde- scribed species. This material he suggested might represent the same form as a tree which I found in South Carolina in March, 1921, and which I discussed with him : a tree of wet flat woods with leaves some- what resembling post oak, but locally regarded as a timber tree much superior to the post oak. It was not possible, however, to secure at that season adequate material for study. Information regarding this tree he thought might be of service to me in connection with the prep- aration of a bulletin on which I worked for the United States Forest Service on the distribution and economic importance of the oaks of eastern United States and on which Mr. Ashe freely gave me assist- ance and suggestions. The description of this tree based on Mr. Ashe 's material and notes is as follows : Quercus ashei, sp. nov. The lower leaves, broadly obovate in outline, are 8-12 cm. long, 5-9 cm. broad, deeply 5-lobed, the terminal lobe and upper pair of lateral lobes very broad at the obtuse or even square ends which are usually slightly 3-notched, the lower pair much shorter and more rounded ; usually rounded at the very narrow base ; thin but firm in texture, dark green and lucid above, and at first more or less stellate pubes- cent, especially on the midrib; much paler beneath, and clothed at least at first with scattered short stellate pubescence, but often glab- rate with age ; midrib slender with one pair of prominent lateral veins at or above the middle; petiole short, 3-6 mm. long, slender, more or less permanently stellate pubescent. The upper, sun leaves, resem- bling those of white oak, thicker, and wdth thickened margin, pinnated into 3-7 ascending entire lobes, rounded or cuneate base and much longer petiole. Buds small, obtuse, dark chestnut, at first with the outer scales stellate pubescent, at length nearly glabrous. Twigs very slender, 2-3 mm. thick, grooved and covered when young with loose brown or brownish-gray pubescence which is usually more or less persistent until autunm. The fruit often in clusters of 2 or 3 is ses- sile or sometimes on a stalk as long as the nut, 12-18 mm. long, in- [178] 1922] A New Oak From the Gulf States 179 eluding the cup ; the cup from 9-12 mm. wide and not quite as long is almost top-shaped or with slightly rounded sides, the margins thin and closely appressed against the nut, closely gray-canescent and cov- ering about one-third of the ovate nut. A tree 20-30 m. in height growing on better drained alluvial lands from the Sabine River in Wood County, Texas, eastward to Winn Parish in Louisiana (type, No. 1128W, from near Hinton, Winn Par- ish, La., in Mr. Ashe's herbarium), with a decidedly tapering usually excurrent trunk 9-12 dm. in diameter, a short bole and rather short spreading branches which form an oblong crown. Bark on trunk steel gray, broken by deep furrows into narrow, flat-topped ridges, rarely exfoliating in thin flakes ; that on the angled limbs and on the branch- lets gray and smoother. Common in willow oak flats and also in association with water oak, Quercus ol>t,usa, Q. prinus, Q. shumardii, and white ash. This tree has the general aspect of a post oak of large size, but the crown is prevailingly much narrower and its slender twiggage is very char- acteristic. From Q. steUata it differs in its slender twigs, smaller and thinner foliage, and small dark red-brown and not large tan buds; from Q. margai etta in its shorter and more rusty pubescence, which largely persists on the twigs; and from both in the far smaller nut and cup and shorter petiole of the shade leaves. It resembles in sev- eral particulars Q. stellata paludosa Sarg. (Bot. Gaz. May, 1918, 441) but that is described as having the fruit similar to the fruit of the post oak, whereas according to Ashe's notes, T. J. Gough, of Hinton, La., woods foreman of the Urania Lumber Company, and others, re- gard the smaller acorns as being one character which separates the two trees ; the very slender twigs and white oak-like upper leaves being other distinctive characters. The local name in Texas is water post oak or swamp post oak ; at Hinton, La., it is water oak, Q. nigra there being called pin oak. Louisiana State Forest Ranger C. N. Bilbray regarded the larger trees in Middle Creek swamp, Natchitoches Parish, La., as white oaks. Washington, D. C. A NEW GENUS OF WATER MOLD RELATED TO BLASTOCLADIA By W. C. Coker and F. A. Grant Plate 32 Septocladia n. genus. Plant small, slender, the short or long stalk not conspicuously dif- ferentiated ; branches usually dichotomous, often verticellate in groups of 3-5, separated from the nodes by distinct and complete septa, not constricted at intervals ; in vigorous cultures repeating the branching in the same way to form a complex plant. Sporangia oval, terminal, sj^mpodially arranged, not rarely in chains of several, often clustered by the shortening of the branches, which continue the stem by one or more lateral buds beneath. Spores biciliate at times, but the two cilia so closely approximated or fused as usually to appear as one. Resting bodies (unfertilized eggs), borne in the same way as the sporangia and of the same size and shape, at maturity enclosed in a thin, hyaline sheath out of which they finally fall through an apical slit ; the wall brown and conspicuously pitted as in Blastocladia : the whole probably representing a thin-walled oogonium completely filled with a thick- walled parthenogenetic egg. A saprophytic aquatic of anomalous structure and differing from all other Phycomycetes in the regular and normal septation of the plant body. To be placed in the Family BJastocladiaceae. Septocladia dichotoma n. sp. Characters of the genus. Threads extending about 3 mm. from the substratum on a termite ant, about 10-73/x thick, growing grad- ually more slender distally at each .ioint, basal joints 35-130^ long, those of central region up to about 675/^, long ; tips blunt, h.y aline. Sporangia oval, 28-46 x 55-76/x; spores escaping singly through one or two usually apical holes or short papillae, biciliate (or uniciliate by fusion of the two cilia?) oval when swimming with the cilia apical, monoplanetic, amoeboid before encysting 10/x thick when at rest ; sprouting by a slender thread. Resting bodies appearing later than the sporangia but of the same shape, 25-39.2 x 36. 3-49. 2/^,, the conspicuous pits apparently sunken from the outside in regular fashion as in Blastocladia Pringsheimii, at maturity slipping from the thin, clasp- ing sheath ; their sprouting not observed. 1922] Water Mold Related to Blastocladia 181 Found only once, October 20, 1921, on a knuckle bone of beef partly covered with water, in Sparrow's pasture, Chapel Hill, N. C. (F. A. Grant col.)- There is no doubt of the close relationship of this plant to Blasto- cladia of which four species are now known, and which was made the type of a new family, Blast ocladiaceae, by Minden (Crypt. Flora, Mark Brand. 5:506. 1912). The four known species of 5Za!5^ocZadia are as follows : Blastocladia Pringsheimii 'Reinach (Jahrb. f. Wiss. Bot. 11:291. 1876). Sporan- gia much elongated, resting bodies with thick and pitted wall, not slipping from a sheath at maturity; sterile, slender filaments often present among the reproductive bodies. Blastocladia rostrata Minden (1. c, p. 604). Much like B. Pringsheimii, but resting bodies slipping from sheath at maturity. Blastocladia ramosa Thaxter (Bot. Gaz. 21:50. 1896). Sporangia shorter; resting bodies with thin and scarcely pitted wall; sterile filaments absent. Blastocladia prolifera Minden (1. c. p. 606). Much like B. ramosa, but sporangia proliferating internally, as in Saprolegnia: the only species with this habit. Eesting bodies slipping from a sheath at maturity. In the form of the sporangia and resting cells and in the absence of sterile filaments among them our plant resembles most closely B. ram- osa and B. prolifera. The remarkable resting bodies with their thick brown, strongly pitted walls and peculiar habit of slipping at maturity from the closely fitting sheath are so strikingly similar in structure and habit to those of B. rostrata and B. prolifera and in structure to those of B. Pringsheimii that one is immediately convinced of their close relationship. The diagnosis of the family will have to be ex- tended to include septate as well as non-septate forms. On an agar plate the plant does not do well, A few root-like threads grow out, branched and with cross-walls in the older portions, and in these older portions are found resting bodies or sporangia, sometimes fifteen or twenty of the latter may be in a row. The re- productive bodies are sometimes found in clusters or single on short lateral stalks. On boiled corn grain the growth is good. The threads are about the same size as on an ant but average longer, as much as 5 mm. The protoplasm in threads is not as dense as when grown on ant. Threads at substratum as large as 102/^ in diameter. Sporangia are produced better than on ants, and resting bodies are so abundant that with the unaided eye they give a brick dust color to the entire 182 Journal of the Mitchell Society [March culture. The resting bodies are at first dark and liave numerous large oil droplets. As they get older the walls assume a yellowish-brown color and the contents become homogeneous. They appear singly along the branches in sympodial arrangement. In a discharging sporangium a few spores that failed to get out were observed to crawl about actively in an amoeboid fashion for a good while. After an hour they had encj'sted and one had sprouted. The spores are of a peculiar internal structure, resembling closely those of B. Pringsheimii as shown by Thaxter (1. c. pi. 3, fig. 11). Most of the protoplasm is at the end opposite the cilia, the center is almost clear and the cilia seem to extend down through the clear tip to a protoplasmic mass below, as shown in our fig. 5. Chapeu Hill, N. C. Explanation of Plate 32 Septocladia dichotoma Fig. 1. Empty sporangia in chains, x 154. Fig. 2. Three sporangia, one discharging spores, two empty, x 420. Fig. 3. Vegetative branch, showing short joints and young resting bodies, x 59. Fig. 4. Optical section of resting body and empty sporangium with two aper- tures. X 420. Fig. 5. Two spores showing cilia, x 1296. Fig. 6. Spores showing amoeboid movement before encysting, x 810. Fig. 7. Sprouting spores, x 1008. Fig. 8. Habit sketch, showing empty sporangia and resting bodies, x 96. Fig. 9. Vegetative tips, showing refractive bodies and clear blunt tips, x 150. Fig. 10. Optical section of mature resting body with empty sporangium below. x 420. Fig. 11. Long, slender thread on corn grain, showing sympodial arrangement of resting bodies, x 96. Fig. 12. Surface view of resting body, showing pits, x 420. Fig. 13. Part of branch, showing thin sheath out of which the resting body (Fig. 12) has slipped, x 420. Fig. 14. Section of thick wall of the resting body, showing the pits and the sheath outside, x 1296. Fig. 15. Mature sporangium just before discharge of spores, x 420. Fig. 16. Group showing some sporangia before maturity and some after empty- ing. X 96. PLATE 32 FOREST TYPES OF THE APPALACHIANS AND WHITE MOUNTAINS By W. W. Ashe I. DEFINITIONS AND ENUMERATIONS OF TYPES* Within the White Mountains of New England and in the Appa- lachiansf from Pennsylvania southward more than 50 distinct forests types or tree societies occur. Of these, more than 30 are within the lAlleghanian area {Castanea and Betula lutea-Pinus strohus phases) of the Transition life zone ; about 10 are in the Canadian life zone, and about the same number in the Carolinian area of the upper Austral zone, which extends well up into the mountains towards their southern end (Appendix 1). DEFINITION OF FOREST TYPE The forest type is that arborescent species or admixture of species with the accompanying subordinate vegetation (which taken together constitute the vert) which nature has developed as best adapted to a given site. For this reason an understanding of the distribution of the forest types, their composition, and the determining environ- mental factors are a necessary basis for the best silvicultural prac- tice. Unf ortunatelj^, site and type have been confused : The site is the sum of the ecological (i. e., edaphic, topographic, and meteorologi- cal) factors; the forest type with its accompanying life is the biotic corollary as it exists. TYPE CHANGES The type does not necessarily, even in the absence of stress, replace itself in all its elements without change. There are (1) changes in composition due to replacement (oscillations) ; and (2) changes due to modification of the accompanying flora, especially the * The detailed composition of the forest types, their relationsliip and local distribution, especially their altitudinal distribution will be presented in subsequent papers, as well as the grouping of the White Mountain forest types. t There was submitted at the meeting of the Society of American Foresters held at Toronto, Canada, December 28, 1921, a paper with the title "Reserved Areas of Forest Types as a Guide in Develojjing an American Silviculture." That paper records the most accessible location of areas in an unmodified oi< little modified condition of each of the upland Appalachian types noted in the tabulation herewith presented. The suggestion was made in that paper that the Society of American Foresters consider the subject of recommending that these areas or similar areas of forst types be withdrawn from exploita- tion and be held primarily for demonstration purposes. That paper, however, was read by title only but will appear in the February, 1922, issue of the Journal of Forestry. [183] 184 Journal of the Mitchell Society [March micro-organisms which promote nitrification. Type replacement may be effected (1) By direct self -replacement under cover, as spruce beneath spruce, or hemlock beneath hemlock, (2) By direct self -replacement without cover, as southern jack pine or mountain pine in openings caused by the death of old trees of the same species. (3) By alternation: Yellow poplar, for example, replacing chest- nut when it windfalls or dies; and chestnut establishing itself be- neath the cover of the poplar ; rosemary pine appearing in oak wind- falls; and oak appearing beneath the cover of the pine. (4) By succession (often following fire or resulting from wind- falls, etc.), as a nurse stand (temporary type) of aspen, birch, and popple followed by a stand (permanent type) of spruce. PERMANENCE OF TYPE While the type is essentially permanent, oscillation in its composi- tion from time to time or intermission in the continuity of its perma- nent form may occur. In addition to such oscillations within the type, the site may be subject at least to slight or temporary modifi- cation by the type (edaphic changes). For example, there is evidence for believing that the accumulation of humus beneath the oak-yellow poplar mixture on certain situations due to retarded nitrification may result in accumulation of raw humus and the development of a subpeaty site and thus favor a change to a chestnut site and chestnut type ; or a chestnut type quality 1 may with increase in peaty accumu- lations and greater acidity become highly favorable for invasion by laurel, and the site decline to chestnut quality 2 with laurel. On swampy sites there may eventually be better drainage as a result of accumulation of humus, resulting in a drying of the site (Appen- dix 2). For instance, an alder and red maple site may become suit- able for red maple and white oak. The type also is subject to change by natural stresses within itself (Appendix 3). The killing of chestnut by Endothia parasitica on large areas is resulting in pro- found changes in the forest types on what originally were chestnut sites; and undoubtedly this must be regarded as constituting an organic change in the forest types in the region which is affected, until or unless a resistant strain is developed from individual trees. Such resistant individuals are often noted. 1922] Forest Types 185 separation of types In deciding what shall be regarded as constituting a permanent forest type or tree society in such a complex as obtains at the southern end of the Appalachians, only such societies have been considered as are most sharply defined and well marked either by composition or, in the case of pure stands (at least 66% pure), by marked differ- ences in the height of the dominant trees and in the volume of wood (quality of stand). The intergrading or transitional stages have been neglected, as well as temporary types. In such societies the quality of the stand, which is an expression of the possibility of yield of the tree society, is considered as important a concept as is varying proportion of species : for example, practically pure stands of chest- nut occur and are widely distributed from Connecticut to north- eastern Alabama, but the chestnut in the pure stands of this species on different sites may vary greatly in height from not to exceed 40 feet along dry and wind-swept upper slopes and crests of ridges, to exceeding 110 feet on sites most favorable for its growth. The same condition is observed in other species, and for this reason to obtain an adequate expression of the forest site the height of the trees in the mixture should be considered as a feature as well as the intermixture of species. With this variation in the height of the overwood there is a concomitant change in the character of the undershrubs and her- baceous associates. In the division of pure stands into types, the height of the domi- nant trees (Appendix 4) in the mature forest has been regarded as the criterion, with an interval of 25 feet (Appendix 5) between the different types. It has been suggested (Appendix 6) that this inter- val be standardized on the basis of 20 feet at 100 years for Appa- lachian species, which for stands of old timber practically conforms to the interval of 25 feet which is being employed. This interval in height results in a difference exceeding 2,000 cubic feet of wood per acre in stands of average height (100 feet), and indicates a great difference in the average amount of available soil moisture in the root zone on soils having the same mechanical condition and depth (Appendix 7), i. e., a difference in the number of critical (dryest) periods and a corresponding difference in the maximum depth of the water table ; or a marked difference in transpiration and evaporation of soil moisture. 186 Journal of the Mitchell Society [March The passage from one forest type to another is seldom abrnpt, but usually there is a g-radual transition, as that which accompanies (1) difference in altitude; (2) variation in drainage, as when the mountain slopes are ascended; or (3) change in the physical texture of the soils, where the soils are residual and have been more or less transported and difference in available moisture results. The most abrupt transition from type to type within a short distance is usually that which is due to difference in insolation, between north and south slopes (Appendix 8), especially when the slopes are steep, or that which results from marked differences in soil composition, especially that between residual soils from the weathering in situ of calcareous rocks (and still containing enough lime to render them alkaline or neutral) (Appendix 9), and contiguous soils derived from a country rock deficient in lime or potash, 111 the eastern prevailingly gneissic, metamorphosed and foliated division of the Appalachians, there is no definite stratification of the country rock, and the forest types occur characteristicall}- in patches. In the Alleghanies, on the other hand, where there is not only definite stratification but great difference in the character of the country rock — soft limestone, cherty limestone, clay shale, sandy shale, sand- stone and quartzite alternating and the extremes often being in juxta- position— the types are prevailingly in horizontal zones along the slopes of the long ridges trending northeast and southwest which characterize the Alleghanian structure, the zonation of the types due to stratification of soils being interrupted by surface configura- tion, where minor valleys and hollows indent the slopes. The facies of the mixed type (society) can often be separated into two groups of species: That portion of it which is formed of species each of which constitutes more than 20 per cent of the stand, con- trolling speci&s, and the minor species each of which forms less than 20 per cent though more than 5 per cent of the mixture. Locals are species of limited distribution and while within a limited area they may be abundant in a type, they do not form a general feature in it throughout its entire distribution (Cladrastis tinctoria, Bohinia viscosa, Magnolia macrophylla, Tsuga caroliniana) . Locals may be species in the formative stage or they may be relics of species possi- bly once of wide distribution which have become nearly extinct. Vagrants are species of wide distribution entering possibly many 1922] Forest Types 187 forest types but seldom sufficiently abundant in any locality to form a distinctive feature in a type (Sassafras, Magnolia acuminata). iA certain species or several species within the facies of the accom- panying vegetation may be so indicative of the type as to be index species. These may be of particular importance in the under shrubs and herbaceous concomitants and have significant value in indicating the character of the superior association after it has been destroyed (Appendix 10). A knowledge of the shrubby and herbaceous index species, especially such as are not affected by the removal of the superior stand (sun species), is economically of paramount impor- tance as a guide in the determination of the quality site in cases where the superior stand has been cut, especially in the case of pure stands. The vert in the Appalachian forests usually may be separated into (1) the superior stand overwood or sun stand of designated species, a portion of the trees in which may be dominant, a portion intermediate and codominant, and a portion suppressed (Appendix 11) ; (2) beneath the superior stand there may be an inferior stand or underwood of trees or shrubs tolerant of shade (such as dogwood, witchhazel, sourwood, laurel, or Kalmia), and below this a ground cover or mat of small shrubs (Vaccinium Leucothoe, Xolisma) as well as an herbaceous flora, each a more or less distinctive and varying concomitant of the forest type. Some of the important features of the forest associations of the Appalachians have been considered in connection with its general phytogeography. Kearney, in an excellent article, discusses some of the forest tj'pes as developed at the extreme southern end of the region. Harshberger considered the central portion of the region in two articles published in 1903 (Appendix 12), and later, 1911 (Appendix 13), covered the subject in a broader manner; while Schimper (Appendix 14) also discussed the forests of this region in their local distribution. The forest types in which chestnut occurs have been briefly considered in "Chestnut in Tennessee," and there are a number of other references in forest literature of the Appa- lachians to the forest types of the region. TABULATIONS OP FOREST TYPES In the tabulations below the following common names are em- ployed (see Journal of Forestry 14: 233. 1916) : 188 Journal of the Mitchell Society [March Mountain pine for Pinus pungens; Black pine for P. rigida; Eoscmary pine for P. echinata; Small shagbark hickory for Hicoria carolinae septentrionalis; Band hickory for H. pallida; Spanish oak for Quercus cocoinea; Spotted oak for Q. shumardii Buck. (See Bull. Charleston Museum 14: 2, 9, 1918) ; Southern red oak for Q. rubra L. (Q. falcata Mx.) ; Mountain lin for Tilia heteropJii/Ua of Authors. Appalachian Forest Formation Associations Societies or Forest Types Spruce Spruce, qualities 2, 3, 4, 5, sub 5. Spruce with southern balsam. Hemlock Hemlock and spruce. Hemlock — birch, qualities 1, 2, 3. Beech — birch — sugar maple Beech — birch — sugar maple, quality 3. Beech pure, qualities 4, 5. Yellow buckeye — sugar maple— yellow birch, quali- ties 2, 3. Mountain lin — black birch — yellow buckeye — white ash, quality 2. Black cherry- — sugar maple — birch — mountain lin, quality 2. Chestnut Qualities 2, 3, 4, 5. Yellow poplar With red oak — chestnut — hemlock, qualities 1, 2. With white oak — sugar maple, quality 1. With white oak — black oak — white hickory, quali- ties 3, 4. With black gum — red maple — white oak, quality 3. Red oak Qualities 4, 5, sub 5. Chestnut oak Qualities 3, 4. 5. White oak * White oak, qualities 2, 3. Mixed oaks (southern red oak and sand hickory). Spanish oak Quality 3. Scrub oak < Scrub oak barrens, quality sub 5. Pin oak With red maple — black gum — alder, quality, 3. Pine types White pine, qualities super 1, 1, 2. White pine, white oak, and chestnut. Black pine and Spanish oak. Eosemary pine and black oak. Eosemary pine and post oak. Eosemary pine and blackjack oak. Spruce pine. Mountain pine. 1922] Forest Types 1^^ PHYSIOGRAPHIC AREAS AND CHIEF ASSOCIATED FOREST TYPES IN APPALACHIANS Canadian Life Zone Highest crests (over 6,000 feet, in North Carolina and Tennessee). Eed spruce (subalpine). Alnus viridis. Rhododendron catawbiense. High crests and thin-soiled upper slopes (5,500 to 6,000 feet, in North Carolina and Tennessee; over 3,500 feet in northern West Virginia. Eed spruce, qualities 4 and 5. Southern balsam, qualities 4 and 5. Medium slopes. Eed spruce, qualities 3 and 4. Lower slopes and valleys (within the Canadian zone) (4,000 to 5,500 feet, in North Carolina and Tennessee; over 3,000 feet in northern West Virginia). Eed spruce, quality 2. (Spruce and yellow birch, intergrading) . (Spruce and hemlock, intergrading). Swamps. Black spruce and southern balsam. Alleghanian Area of Transition Life Zone Very high crests (over 5,000 feet, in North Carolina and Tennessee; over 2,500 feet in northern West Virginia). Beech pure, quality 4. Eed oak pure, quality sub 5. Chestnut pure, quality 5. High crests. Chestnut pure, quality 5. Chestnut oak pure, quality 5. Scrub oak, quality sub 5. Eed oak pure, qualities 4 and 5. Lower crests. Spruce pine — chestnut oak, quality 4. Mountain pine— black oak, quality 4. Chestnut oak pure, qualities 4 and 5. Scrub oak, quality sub 5. Yellow poplar— black oak— white hickory, quality 4. High slopes, north and west aspects. Yellow buckeye— sugar maple— yellow birch, qualities 2 and 3. Beech— yellow birch— sugar maple, quality 3. Hemlock — 'birch, qualities 2 and 3. 190 Journal of the Mitchell Society [March High benches. Black cherry — sugar maple — mountaiu liu — black birch, quality 2. Bed oak pure, qualities 4 and 5. Beech pure, qualities 4 and 5. High slopes, south aspects. Chestnut pure, qualities 4 and 5. Slopes (middle altitudes), northern and western aspects. Chestnut pure, qualities 3 and 4. White oak pure, quality 3. Hemlock — birch, qualities 1 and 2. Black pine — chestnut oak — Spanish oak, quality 4. Slopes (middle altitudes), southern aspects. Chestnut pure, qualities 3 and 4. Chestnut oak pure, qualities 3 and 4. White oak pure, quality 3. Slopes (lower) northern aspects. Chestnut pure, qualities 2 and 3. White oak pure, qualities 2 and 3. Spanish oak pure, quality 3. Yellow poplar — white oak — black oak — white hickory, qualities 3 and 4. Slopes (lower) southern aspects. Chestnut pure, qualities 2 and 3. Chestnut oak pure, quality 3. White oak pure, qualities 2 and 3. Hollows, ravines, coves. Chestnut pure, quality 2. Mountain lin — buckeye — ash, quality 2. Yellow poplar — chestnut — red oak — hemlock, qualities 1 and 2. Yellow poplar — white oak — sugar maple, quality 1. AUuvials (drained) and valleys. Yellow poplar — white oak — black gum — red maple, quality 3. Beech pure, quality 4. White pine, qualities super 1, 1 and 2. Hemlock, qualities 1 and 2. Swamps. Eed maple — inn oak — alder — green ash — black gum. Carolinian Area of Upper Austral Life Zone Crests and dry flats (under 2,500 feet, in North Carolina ; under 1,500 feet in Augusta County, Virginia) . Rosemary pine and post oak, quality 3. Rosemary pine and blackjack oak, quality 4. Slopes and flats. Rosemary pine — black oak — white hickory, quality 2. 1922] Forest Types 191 Black oak — southern red oak — white oak— sand hickory, quality 2. Spotted oak — black oak — northern red oak — chinquapin oak — southern sugar maple — Biltmore ash, quality 3. Chinquapin oak — small shagbark hickory — northern red oak — post oak — red cedar, quality 4. Alluvials and riparian. Sweet gum — swamp southern red oak — spotted oak — black gum — Acer tridens — green ash — Celtis laevigata, quality 2. Sweet gum — white oak — black gum— shagbark hickory — sycamore, quality 2. Eiver birch — sycamore — red maple — black willow, quality 3. MOST IMPORTANT VEGETATION TYPES (APPALACHIANS) Mesophytic associations Deep soils. White oak societies. Yellow poplar societies. Chestnut societies. Black oak — southern red oak society. Medium soils. Black cherry — birch, quality 2. Spanish oak, quality 3. Yellow buckeye — white ash — mountain lin societies. Shallow soils. Eed oak societies, qualities 4, 5 and sub 5. Beech, qualities 4 and 5. Xerophytic associations Mountain pine. Spruce pine. Black pine. Yellow pine. White pine. Scrub oak, quality sub 5. Lithophytic associations. Chestnut oak societies. Eed spruce societies. Hemlock — yellow birch, quality 3. Psychrophytic associations. Eed oak, quality sub 5. Alnus viridi^. Bhododendron catawbiense. Hemlock — yellow birch (to southward). Yellow buckeye— sugar maple — birch (to southward). Beech, quality 5. 192 Journal of the Mitchell Society [March Oxylophytic associations. Chestnut with laurel, qualities 4 and 5. Rhododendron catawhiense. Selophytic associations. Ecd maple — black gum — greeu ash — alder. For most of the forest types listed the quality sites are g-iven, the quality of the site beino- indicated by the dominant trees in the super- ior stand havino- the general range of heights as follows : Quality super 1 140 feet and over Quality 1 125-139 feet Quality 2 100-124 feet Quality 3 75-99 feet (average) Quality 4 50-74 feet Quality 5 25-49 feet Quality sub 5 Under 25 feet r- ~ ~ FOREST TYPES OF CANADIAN LIFE ZONE WITHIN THE APPALACHIANS In the Canadian Life Zone the following forest types are repre- sented in the Appalachians : 1-5. Eed spruce, qualities 2, 3, 4, 5, sub 5 (subalpine). 6. Southern balsam, quality 4 7. Alnus viridis (local). 8. Rhododendron catawhiense (local). 9. Black spruce — balsam (local). FOREST TYPES OF ALLEGHANIAN AREA, TRANSITION ZONE In tlie Alleghanian area of the Transition Zone there are two dis- tinct forest divisions : the chestnut phase and the white pine and sugar maple — birch phases. The chestnut phase is the more southern, while the forest types of the white pine and sugar maple — birch phases are more representative of the Alleghanian area to the north- ward. In the following notes the paragraphs are numbered according to the numbers of the types. 1-4. Chestnut pure types, qualities 2, 3, 4 and 5. These types Avith their transitions to other types occupy not less than 10 million acres from Connecticut to northern Alabama. They are located especially on the acid and subacid (often semi-peaty top soil, Porter black loam of the Bureau of Soils series) soils from gneiss, metamorphosed sandstone and sandstone deficient in lime and potash (Appendix 15). 5-7. Chestnut oak pure types, qualities 3, 4 and 5. These types occupy not 1922] Forest Types 193 less than 2 million acres from Pennsylvania southward. They are located especi- ally on soils derived from sandstone and shale. 8-9. White oak pure types, qualities 2 and 3. These types occupy not less than one million acres. They are especially developed on the dryer soils derived from shales and located to the west of the Blue Eidge, though they likewise occur along and to the east of the Blue Eidge in northern Virginia and to the northward. 10. Spanish oak type, quality 3. This type occupies not less than 500,000 acres. It is especially developed on the dryer phases of subacid soils derived from gneiss between 2000 and 4000 feet altitude in the mountains of western iSTorth Carolina. In south central Pennsylvania, Maryland and northern Virginia it occurs at altitudes between 1,000 and 2,000 feet. 11. Scrub oak type, quality sub 5. This type occurs usually in small areas, the aggregate being not in excess of 50,000 acres, largely in Virginia, West Virginia and to the northward. In the mountains of Virginia, West Virginia and Maryland it is characteristically developed on shallow soils derived from sandstones and shale. It fringes many of the shrubby barrens along the crests of the Shenandoah Mountains. 12-13. Yellow buckeye— sugar maple — yellow birch types, qualities 2 and 3. This society extends southward from Roan Mountain (Appendix 16) to the Great Smoky Mountains, being typically developed on north slopes between altitudes of 4500 and 6000 feet. They occupy thousands of acres in the Smoky Mountains, where they are at their optimum. To the northward by dilution they merge into the beech — birch — maple society. 14. Black cherry — sugar maple — mountain lin — black birch type, quality 2. This type is probably at its optimum in West Virginia and Pennsylvania on elevated portions (3000 to 3500 feet) of the Alleghany plateau. In North Caro- lina it occurs only in patches usually between 4500 and 5500 feet. In West Virginia, however, the lin ceases to be a component. 15. Mountain lin — yellow buckeye — white ash type, quality 2. Most char- acteristically developed along the eastern Appalachians in Tennessee and North Carolina between 3000 and 5000 feet altitudes, prevailingly in coves and hollows. It does not extend north of West Virginia. 16-17. Yellow poplar — chestnut — red oak — hemlock types, qualities 1 and 2. These are characteristic cove types of the southern Appalachians and are at their optimum between southeastern Kentucky and the mountains of northern Georgia. Quality 1 produces heavier yields of hardwood lumber than any other association within the AUeghanian area. It is best developed between 2500 and 3800 feet in North Carolina and Tennessee. In middle Pennsylvania, where its identity is lost, it occurs below 2000 feet altitude. 18. Yellow poplar — white oak — black gum — red maple type, quality 3. This forest type indicates the wettest site on which yellow poplar naturally gi-ows. It is well developed on gravelly flats on the head of Davidson Elver, Transylvania County, N. C, but is not uncommon on similar sites throughout the region. 19. Yellow poplar — white oak — sugar maple type, quality 1. This society is characteristically developed in middle Kentucky, middle Tennessee, and extends 194 Joi^RNAL OF THE MiTCHELL SOCIETY [Mavch southward through the Sand Mountain of nortliern Alabama. It occupies not less than a million acres, much of it on limestone soil, being some of the most productive land in these states. 20-21. Yellow poplar — white oak — black oak-^white hickory (big leaf cu- cumber) types, qualities 3 and 4. These types are typically developed on sandy soils, often calcarious, on the Cumberland Mountains in Tennessee and the Sand Mountain in Alabama. Quality 4 represents the dryest site on which the yellow poplar occurs. 22-23-24. Bed oak pure types, qualities 4, 5 and sub 5. These types occur in comparatively small bodies along crests of ridges and north slopes with shallow soil from Pennsylvania southward to northern Georgia. In northern Georgia and the adjacent territory they occur between 3000 and 5000 feet alti- tudes. They probably occupy in excess of 100,000 acres. In the White Moun- tains these types occupy south slope or valleys (as on Oliverian Brook, Bethlehem, Grafton County, N. H.). 25-26. Beech pure types, qualities 4 and 5. These stands occupy compara- tively small areas along the crests of the ridges, mountain summits, and benches on upper slopes between (in North Carolina) 4500 and 6000 feet. It is dou]>tful if the aggregate area exceeds 10,000 acres. (Appendix 17.) 27. Beech — yellow birch — 'sugar maple type, quality 3. Tliis forest type occupies several million acres. To the northward it is characteristically developed at medium altitudes on loamy and clay soils, often rocky. To the southward it becomes limited to north slopes and correspondingly higher altitudes, phases of it frequently occupying extensive areas of stony soil, especially on the Cumberland plateau and the north slopes of sandstone ridges. 28. Bed maple — pin oak — green ash — black gum — alder type. This is charac- teristically a type of the wet clay flats and wetter alluvials and enters the Appa- lachians only in Virginia, West Virginia and Pennsylvania. It is one of the less imi^ortant types occupying comjjaratively small areas. South of West Virginia pin oak is absent. 29-31. Hemlock — birch types, qualities 1, 2 and 3. These occasionally are almost pure hemlock. While the birch is prevailingly yellow birch., there is, especially toward the South, a considerable admixture of black birch. These types once occupied not less than 10 million acres in the Eastern States. The present area of the unlumbered types probably is less than a million acres, mostly in small bodies. Quality 3 is characteristically developed on soils which are either wet, on account of lack of drainage due to the stony substratum, as developed around Highlands, N. C, or there is better drainage and the type is located on north slopes with poor insolation, as occurs throughout the Shenandoah Mountains. (Appendix 18.) 32. Spruce pine — chestnut oak — chestnut type, quality 4. This type is most characteristically developed on the points of shale and sandstone ridges in Ken- tucky and Tennessee. It occurs, however, to the northward on similar sites through extreme northeastern West Virginia and northern Virginia to Mary- land and is likewise Avell developed in places on spurs of the Blue Ridge in 1922] Forest Types 195 western North Carolina and even occasionally as far south as Jasper County, Alabama. 33. Mountain pine — chestnut oak — black oak type, quality 4. In North Caro- lina, South Carolina and northern Georgia this type is developed on heavy clay soils on crests of spurs of the Blue Eidge Mountains between altitudes of 1500 and 3000 feet. This type occurs occasionally in the mountains of Tennessee and Kentucky and probably extends nortliward to Pennsylvania. 34-37. White pine pure, qualities super 1, 1 and 2. These types formerly occupied many million acres, especially to the northward. In the Appalachians they become localized and restricted in area, being best developed between altitudes of 500 to 2000 feet in Pennsylvania and 3000 to 4000 feet in Tennessee and North Carolina. They are the exponent of sandy or gravelly soil phases. In many places in the Appalachians they intergrade with hemlock qualities 1 and 2, as is the case in the Shady Valley, Tennessee, and other nearby valleys, or (No. 37) into chestnut — white oak as in the upper valley of the Linville Kiver in North Carolina and Horse Creek Valley in Blount County, Tennessee, quality 1. 38. Black pine — chestnut oak — Spanish oak type, quality 4. Characteristically a type of sandy or gravelly soils; in the extreme south on northwest slopes at higher altitudes but to the northward seeking other exposures and level sites. FOREST TYPES OF CAROLINIAN AREA WITHIN THE APPALACHIANS In the Carolinian area of the Upper Austral Life Zone the fol- lowing forest types are represented : 1. Eosemary pine — black oak — white hickory type, quality 2. A widely dis- tributed type throughout the Piedmont, occupying not less than 5 million acres, and the source of much yellow pine timber. In the Valley of Virginia it ascends to an altitude of 1100 feet; and in the Asheville Basin to 2600 feet. Its identity is lost in western Maryland and southern Pennsylvania. 2. Eosemary pine — post oak type, quality 3. A widely distributed type in the Piedmont. In the mountains it is largely restricted to low ridges in North Carolina, Tennessee and southward and does not ascend above 2500 feet in North Carolina. 3. Eosemary pine — blackjack oak type, quality 4. Widely distributed in the Piedmont. In the Appalachians it is largely limited to low ridges, seldom ascending above 2000 feet in North Carolina, Tennessee and southward; or 1100 feet in Augusta County, Virginia. 4. Black oak — southern red oak — wliite oak — sand hickory type, quality 2. Best developed at the lower altitudes and on dryer sites on the Cumberland, Plateau of Tennessee and to be southward in Alabama, specially on calcarious sandy soils. 5. Spotted oak — black oak — northern red oak — chinquapin oak — southern sugar maple — Biltmore ash type, quality 3. At the southern end of the Alle- ghany ranges this is a common society on slopes and in hollows on soil derived from limestone. It is doubtful if it extends northward beyond Kentucky. liJt) Journal op the Mitchell Society [3Iarch 6. Cliiiiquapin oak — small shagbark hickory — post oak — red cedar type, quality 4. This covers a large portion of the limestone barrens of Tennessee and Alabama. It passes especially at lower altitudes and outside of the moun- tains into pure red cedar (cedar barren). 7. Sweet gum — swamp southern red oak (Quercus pagoda) — spotted oak — black gum — Acer tridens — green ash — Celtis laevigata type, quality 2. This occurs along alluvials of larger streams at the southern end of Appalachians at altitudes of 2,000 feet or less. (Appendix 18.) 8. Sweet gum — white oak — black gum — shagbark hickory — sycamore type, quality 2. This occurs on alluvials, chiefly of smaller streams at altitudes below 3000 feet in northern Georgia and below 1000 feet in the mountains of Virginia. 9. Eiver birch — sycamore — red maple — black willow type, quality 3. This is a riparian type and occurs on alluvials of smaller streams at altitudes below 2500 feet at the southern end of Appalachians, and in Maryland below 800 feet. APPENDIX (1) In Augusta County, Virginia, the Carolinian zone ascends to 1,100 feet; in the French Broad basin, and southward to approximately 2,600 feet on sunny slopes. See also Kearney, Science 12:831. 1900. (2) See also Warming, Ecology, 359. (3) Among the most important of these natural causes may be mentioned insects. White pine and black pine have been practically exterminated over wide areas from Pennsylvania southward since 1870 by the southern pine beetle, Dendroctomis frontalis (see Hopkins' reports). Chestnut has ceased to exist in great portions of Alabama, Georgia and the Carolinas, largely as a result of the two-line chestnut borer and the root fungus. (See "Chestnut in Tennessee," page 11.) Within the past decade the composition of stands in which the hickories form a significant element has been seriously modified, especially in northern Illinois and the adjacent region, by an insect (Scolytus quadrispinosus). Two decades ago there was a similar modification in the composition of oak, hickory, and rosemary pine stands in Piedmont Carolina, through the dying out of the southern red oak and black oak, there being in many places a displace- ment of the natural equilibrium which cannot be restored for many years. How large a part drought, an extended period of which terminated about this time, and insects relatively contributed to this condition is a subject of conjecture. (4) Dominant is employed in the sense of exceeding all other in height, its significance in an extensive forest literature (see Standard Dictionary). Con- trolling species is used to designate such as are numerically preponderant. (5) The basis for division is approximately the same as that Avhich has been used in the work of appraising hardAvood timber lands for purchase for eastern National Forests; i. e., an interval of 16 feet in the length of the merchantable stem (a standard saw-log length) or 25 feet as the difference in the height of the crown of the dominant trees, since approximately one-third of the total height of a tree with a deliquescent form is in the crown and tAvo-thirds in the stem. 1922] Forest Types 197 (6) Frothingham, Journal of Forestry 19:1. 1921. (7) Mechanical condition is the basis for the classification of soil types employed by the Bureau of Soils of the Department of Agriculture ; while the moisture content, and the number of times that the critical moisture period is reached (Briggs and Schantz, the wilting coefficient) are determined by (1) humus content and granulation, (2) depth of water table, (3) transpiration factors of wind and insolation, the precipitation being the same; and these are controlling factors in determining site. (8) Kearney, Science 12:841. 1900. Noted particularly also by Shreve, Vegetation of a Desert Mountain, 97. 1915. The result of differences in inso- lation is noticeable to a marked degree in the southern portion of Walker County and in Jasper County, Alabama, along the southern edge of the Alabama National Forest. Here on the uplands are typical forests of longleaf pine while in the deep gorges of the streams penetrated by direct sunlight only during a few hours each day may be found fragments of hemlock — black birch type; and the yellow poplar — cucumber — beech — black birch — northern red oak mixture. To a less extent this is also noticeable in the deep hollows which indent the bluff formation along the Mississippi River in its most dissected phases. (9) Contrary to general opinion, many of the surface soils derived from limestones, in cases where the unaltered limestone is at a great depth, are not only not neutral but even acid. This is due to the fact that the so-called lime- stone soils, produced from the weathering of impure limestone, are residuals, consisting of the less soluble, chiefly silicious materials. The more rapid is erosion the thinner, as a rule, is the residual blanket permitting the roots of more plants to come in contact with the calcareous elements in the unleached limestone. Many of the residual soils in the Appalachians from the Silurian and Cambrian limestones, consequently, are acid and support stands of plants asso- ciated with acid soils. (10) North Carolina Pine, Bull. 24, N. C. Geo. Survey, p. 57. 1915. (11) In the superior stand or sun stand certain species (like yellow poplar) may be largely intolerant of shade throughout their entire life period. Such species produce relatively few suppressed trees in the mature stands. Other species, like beech and white oak, are tolerant for a long period and consequently produce many suppressed specimens; while tolerance of some others, like balsam, progressively declines with age. The leaves of dominant and suppressed trees of the same species, or the sun and shade leaves on dominant trees may be quite different. In the southern red oak and its races the sun leaves are smaller, more divided, and more densely pubescent beneath. In TiJia lieterophylla of Authors the shade leaves are larger, thinner, and often glabrous, having been mistaken for T. glabra, whereas the sun leaves are silvery-white pubescent beneath. The records of the occurrence of T. glabra in the eastern Appalachians are largely based on collections of such shade leaves. (12) Botanical Gazette 34:241, 369. 1903. Unfortunately the value of these articles is marred by a number of errors in the determination of very com- 198 Journal op the Mitchell Society [March mon trees, as, for example, Qucrcus phellos is credited to the valley of the Swan- nanoa River, when the species should be Q. imhricaria. (13) Phytogeography of North America, 1911. (14) Plant Geography. (15) Coville, Formation of Leaf Mould, An. Rept. Smiths. Inst., 338-340. 1913. (16) Harshberger, Bot. Gaz. 36:375. 1903. (17) Kearney (1. c, 831) regards beech as being characteristically a tran- sitional or northern tree. He apparently overlooked the fact that beech reaches its best development along the bluff formation in Louisiana and Mississippi, and that there are magnificent forests which contain a large proportion of this tree throughout other portions of the Gulf States and Tennessee. It occurs to the very coast in North Carolina (var. caroJiniana) and forms nearly pure stands on the beech flats around the southern edge of the Dismal Swamp. Stone (Plants So. N. J., p. 84, 1911) records beech as forming pure stands in New Jersey. It is probable that the New Jersey tree is the same as the North Carolina coastal form. (18) The tendency is for southern tyjjes especially those of the low-lands to extend up the valleys of the streams beyond the general limits of the life zone of which they are representative as finger-like projections into the more northern types when deficiency in insolation is not a controlling factor. This is particularly noticeable when the soils of the lowlands are sandy and consequently * ' warm, ' ' while those of the surrounding uplands are clayey and ' ' cold. ' ' Such projecting tentacles of southern types are noticeable in Tishomingo County, Mississippi, on the sandy alluvials of Bear Creek where typical lower austral societies, such as tupelo, cypress, button bush, white bay, southern red maple and alder occur contiguous to the yellow j^oplar, white oak, black oak, white hickory, big leaf cucumber society on the adjacent slopes of the Pearson hills which are the southwestern outlyers of the Appalachians. Similarly the intrusion of fingers of the Carolinian alluvial flora into the transitional are noticeable in eastern Tennessee and western North Carolina. On the other hand, when deficient inso- lation is a controlling factor tentacles of northern types penetrate areas in which southern types prevail. Such cases are the colonies of hemlock and birch which occupy the deep gorges of the Sipsey and other rivers in Jasper County^ Alabama (see also Appendix No. 8), or the groups of these trees on steep north slopes along the south bank of the Potomac River below Great Falls, Virginia. Forest Service, "Washington, D. C. INDEX TO VOLUMES 32-37 VOL. PAGE Achlya Orion, a new species, Coker and Couch 36 100 Aecidiaceae 35 115 Agarieaceae, key to the genera, Coker 35 24 Age of insects, Metcalf 37 19 Aleurodiscus 36 152 acerinus 36 156 botryosus 36 157 candidus 36 154 candidus var. sphaerosporus 36 155 macrodens 36 155 nivosus 36 156 Oakesii 36 153 Allard, Harry Ardell Effect of the relative length of day and night on plants (•with W. W. Garner). Abstract 37 108 Amanita 33 17 abrupta 33 71 Atlcinsoniana 33 84 Caesaria 33 19 chlorinosma 33 76 cinereconia 33 86 cothurnata 33 46 excelsa 33 57 flavorubescens 33 62 Frostiana 33 65 gemmata 33 42 hygroscopica 33 33 magnivelaris 33 35 mappa 33 37 mappa var. lavendula 33 39 inuscaria 33 49 mutabilis 34 198 nitida 33 87 pliaUoides 33 27 porphyria 33 26 recutita 33 24 rubescens 33 59 ruhescens var. alba 33 62 soUtaria 33 68 spissa 33 53 si)issa var. alba 33 56 si)reta 33 20 [199] 200 Journal of the Mitchell Society [March Amanita — Coutinued VOL. PAGE spreta var. parva 33 23 strohiliformis 33 73 verna 33 30 virosa 33 83 Amanitas of the eastern United States, Coker 33 1 Amanitopsis 33 5 agglutinata 33 11 farinosa 33 14 parcivolvata 33 10 puhescens 33 14 pusilla 33 16 strangulata 33 8 vaginata 33 6 Animal kingdom, nature of the individual, Wilson 32 125 Anthracnose, false 36 73 Arborescent flora of North Carolina, additions, Ashe 34 130 Abbuckle, Howard Bell An interesting fertilizer problem 36 94 Report of an investigation as to cause of death, of chicks in shell in artificial incubation 34 141 Arsenic in arsenates, determination. Bell 35 90 Ashe, William Willard Additions to the arborescent flora of North Carolina 34 130 The eastern shrubby species of Robinia 37 175 Asterostroma 36 164 cervicolor 36 164 Auricularia 35 120 auricula- judae 35 120 Auricularinceae 35 119 Azalea atlantica Ashe and its variety luteo-alba n. var., Coker 36 97 Baity, Herman Glenn An interesting maximal case (with A. Henderson) 37 61 Basidiomycetes of North Carolina, Coker 35 113 Batesburg, S. C, and vicinity, list of plants, McGregor 33 133 Battle, Kemp Plummer Dr. Joseph Austin Holmes at the University of North Carolina 32 20 Bayley, William Shirley A magnetite-marble ore at Lansing, N. C 37 138 Beardslee, Henry Curtis Collybias of North Carolina (with W. C. Coker) 37 83 A new species of Amanita 34 198 Russulas of North Carolina 33 147 Beaufort, N.C., molluscan shells, Jacot 36 129 Beaufort, N.C., sponges, George and Wilson. Abstract 37 112 Bell, James Munsie A rapid volumetric method for the determination of arsenic in arsenates 35 90 1922] Index to Volumes 32-37 201 Bell, James Munsie — Continued vol. page Biology course, general, considerations in its defense, Givler 37 123 Botanical bonanza in Tuscaloosa County, Alabama, Harper 37 153 Beimley, Clement Samuel Brief comparison of the herpetological faunas of North Carolina and Virginia 34 146 Eliminations from and additions to the North Carolina list of reptiles and amphibians 34 148 Key to the butterflies of North Carolina 37 73 Our rats, mice and shrews 35 55 Some kno^vn changes in the land vertebrate fauna of North Carolina 32 176 The turtles of North Carolina; with a key to the turtles of the eastern United States 36 62 Butterflies of North Carolina, key, Brimley 37 73 Cain, "William Teaching of geometry, by Archibald Henderson. A review.... 37 109 Contributions to the scientific study of earth pressure. Ee- viewed by Henderson 32 115 Calocera 35 181 cornea 35 181 cornea var. minima 35 182 viscosa 35 181 Cantharellus 35 37 aurantiacus 35 43 cibarius 35 42 cinnabarinus 35 45 clavatus 35 44 floccosus 35 41 infundibuliformis 35 39 lignatilis 35 47 minor 35 46 muscigenus 35 39 retirugus 35 38 sinuosus 35 40 umhotiatus 35 47 Cantharellus in North Carolina, Coker 35 24 Chapel Hill, shrubs and vines, Coker and Totten 32 66 Chicks, death in artificial incubation, Arbuckle 34 141 Chlorination by mixed carbon monoxide and chlorine, Venable and Jackson 35 87 Church's Island, N. C, flora, McAtee 35 61 Circular curves, new method for laying out, Hickerson 36 42 Coker, William Chambers Amanitas of the eastern United States 33 1 Azalea atlantica and its variety lutco-alha n. var 36 97 202 Journal of the Mitchell Society [March CoKER, William Chambers — Continued vol. page CoUybias of North Carolina (with H. C. Beardslee) 37 83 Craterellus, CantJiareilus and related genera in North Carolina ; with a key to the genera of gill fungi 35 2-i Distribution of Bhododendron catawbiense, with remarks on a form 35 76 Hydnums of North Carolina 34 163 Lactarias of North Carolina 34 1 The Laurel Oak or Darlington Oak (Quercus Laurifolia Michx) 32 38 A new genus of water mold related to Blastocladia (with F. A. Grant) 37 180 A new species of Achlya (Avith J. N. Couch) 36 100 Notes on the lower Basidiomycetes of North Carolina 35 113 Notes on the Thelephoraceae of North Carolina 36 1-46 Shrubs and vines of Chapel Hill (with H. R. Totten) 32 66 A visit to Smith Island 34 150 Collybia alba 37 99 butyracea 37 86 cirrata 37 96 clusilis 37 105 confluens 37 101 conigena 37 98 conigenoides 37 98 distorta 37 91 dryophila 37 87 Earleae 37 89 exsculpta 37 95 hariolorum 37 101 Ulacina 37 104 maculata 37 85 myriadophylla 37 91 nummularia 37 90 platyphylla 37 94 radicata 37 92 semitalis 37 ' 92 stipiiaria 37 103 velutipes 37 100 zonata 37 102 Collybias of North Carolina, Coker and Beardslee..; 37 83 Coniophora 36 157 arida, 36 157 Corticium 36 168 arachnoideum 36 172 caeruleum 36 169 lilacino-fuscum 36 170 roseum 36 171 1922] Index to Volumes 32-37 203 Corticium — Continued vol. page scutellare 36 171 Stevensii 36 174 suhcoronatum 36 174 vagum 36 173 Fiticola 36 172 Couch, John Nathaniel A new species of Achlya (with W. C. Coker) 36 100 Cratetlellus 35 31 calyculus 35 36 cantharellus 35 32 cornucopioides 35 34 lutescens 35 35 ochrosporus 35 35 odoratus 35 33 roseus 35 34 Craterellus in North Carolina, Coker 35 24 Cunningham, Bert Notes on occurrence of Tintinnus serratus in Chesapeake Bay.... 35 12 The occurrence of unlike ends of the cells of a single filament of Spirogyra 36 127 A pure culture method for diatoms 36 123 Cyphella 36 148 eapula 36 150 cupulaeformis 36 150 fasciculata 36 149 muscigena 36 149 Dacrymyces 35 160 abietinus 35 161 aurantnis 35 163 azaleae 35 174 capitatus 35 173 clirysocomus 35 172 cinnaharinus 35 174 conglohatus 35 172 difformis 35 173 Ellisii 35 167 epiphyllus 35 173 fragiformis 35 172 fuscomitms 35 171 involutus 35 164 minor 35 168 pallidus 35 171 pedunculatus 35 166 pellucidus 35 173 syringicola 35 172 violaceus 35 172 204 Journal of the Mitchell Society [3Iarch Dacrymyces — Continued vol page viticola 35 173 Dacrymycetaceae 35 160 Bacryomltra 35 174 duMa 35 174 Bacryopsis 35 175 ceracea * 35 175 Darlington Oak, Coker 32 38 Darlingtonia 34 112 Dendrium buxifolmm, Coker 34 153 Detjen, L. E. Pollination of the rotundifolia grapes 33 120 Diatoms, pure culture method, Cunningham 36 123 Diorites near Chapel Hill, N.C.. Smith 33 128 Ditiola 35 178 albizziae 35 180 radicata 35 178 Dyestuff situation, critical condition, Wheeler 32 53 Earth pressure. Professor Cain's contributions to the scientific study, Henderson 32 115 Eclipse of the sun, June 8, 1918, Lanneau 34 76 EicMeriella 35 155 Levcilliana 35 155 Elisha Mitchell Scientific Society, origin 32 17 Proceedings, Dec. 1912 to Dec. 1916 32 121 Proceedings, Dec. 1916 to March 1920 36 1 Proceedings, May 1920 to Dec. 1920 36 103 Proceedings, Feb. 1921 to May 1921 37 1 Embryos with spina bifida defect, Wilson and Mabkham. Abstract 37 113 Eomycenella 35 28 EcMnocephala 35 28 Exidia 35 130 applanaia 35 151 Beardsleei 35 133 gelatinosa 35 131 glandulosa 35 132 lurida 35 151 pinicola 35 150 scutellae forme 35 150 spiculata 35 151 Exobasidium 36 147 Vaccina 36 148 Fauna of North Carolina, land vertebrate, some known changes, Brimley 32 176 Fernworts of Florida, Small 35 92 Fertilizer problem, Arbuckle 36 94 Fisheries of North Carolina, Pratt 32 149 1922] Index to Volumes 32-37 205 VOL. PAGE Fishes in relation to mosquito control, Hildebrand 37 161 Flora of Church's Island, McAtee 35 61 Florida, fernworts, Small 35 92 Garner, Wightman Wells Effect of the relative length of day on plants (with H. A. Allaed). Abstract 37 108 "Geometry, Teaching of," by Archibald Henderson. Eeviewed by Gain 37 109 George, Wesley Critz An interesting anomaly in the pulmonary veins of man 37 173 Sponges of Beaufort (N. C.) harbor and vicinity* (with H. V. Wilson). Abstract 37 112 Gill fungi, key to the genera, Coker 35 24 Givler, John Paul Notes on the oeeology and life-history of the Texas Horned Lizard, Phryuosoma cornutum 37 130 Some considerations in defense of thej general biology course.... 37 123 Grant, Freeman Augustus A new genus of water mold related to Blastoeladia (with W. 0. Coker) 37 180 Grapes, rotundifolia, pollination, Detjen 33 120 GuDGER, Eugene Willis On Leidy's Ouramoeia and its occurrence at Greensboro, N. C. 32 24 "A primer of household biology." Eeview by Wolfe 34 154 Guepinia 35 176 elegans 35 176 spathularia 35 177 Gymnosporangium 35 116 germinale 35 117 Juniperi-virginianae 35 117 Nidus-avis 35 118 Harper, Eoland McMillan The American pitcher-plants 34 110 A botanical bonanza in Tuscaloosa County, Alabama 37 153 Eegional geography of South Carolina illustrated by census statistics 35 105 Some North Carolina soil statistics and their significance 33 106 Henderson, Archibald An interesting maximal case (with H. G. Baity) 37 61 ligniotus 34 51 luteolus 34 55 minusculus 34 43 mucidus 34 25 Peclcii 34 45 Professor Cain's contributions to the scientific study of earth pressure 32 115 "Teaching of Geometry." Eeviewed by Cain 37 109 206 Journal of the Mitchell Society [March VOL. PAGE Herpetological faunas of North Carolina and Virginia, Brimley 34 146 Herpetology of North Carolina, Schmidt 32 33 HiCKERSON, Thomas Felix A new method for laying out circular curves by deflections from the P. 1 36 42 HiGGiNS, Bascombe Britt Notes on the morphology and systematic relationship of Sclero- tium Eolfsii Sacc 37 167 HiLDEBRAND, SaMUEL FREDERICK Fishes in relation to mosquito control 37 16] Holmes, John Sim cox Extension of the range of Prunus umbellata into North Carolina 34 126 Some notes on the occurrence of landslides 33 100 Holmes, Joseph Austin, at the University of North Carolina, Battle 32 20 bibliography of writings 32 11 memorial sketch, Pratt 32 1 reminiscences, Venable 32 16 Eydnellum 34 181 caroUnianum 34 189 diabolus 34 182 ferrugipes 34 188 floriforme 34 187 humidum 34 191 Nuttallii 34 183 scrohiculatum 34 184 velutinum 34 183 zonatum 34 18f Hydnochaete 34 197 olivaceum 34 197 Uydnum 34 163 albo-magnum 34 167 cristatum 34 169 fuliginco-violaceum 34 173 fumosum 34 175 imbricatum 34 168 Murrilli 34 174 repandum 34 166 roseolus 34 175 scabripes 34 170 Underwoodii 34 171 Hydnums of North Carolina, Coker 34 163 Hymenochaete 36 166 agglutinans 36 168 corrugata 36 167 Curtisii 36 167 1922] Index to Volumes 32-37 207 VOL. PAGE Hypochnus 36 165 atroruber 36 165 fuscus 36 166 Incubation, artificial, death of chicks, Arbuckle 34 141 Individual in the animal kingdom, nature, Wilson 32 125 Insects, Age of, Metcalf 37 19 Involution, theorem on double points, Lasley 37 80 Isotopes, Venable 37 115 Jackson, David Houghton Chlorination by mixed carbon monoxide and chlorine (with F. P. Venable) 35 87 Jacot, Arthur P. Some marine molluscan shells of Beaufort and vicinity 36 129 Juglone, Wheeler 35 49 Kidney cells, normal and nephropathic, occurrence and distribution of potassium, MacNider 32 113 Lactarias of North Carolina, Coker 34 1 Lactarius agglutinatus 34 27 Allardii 34 12 atroviridis 34 16 camphoratus 34 57 Chelidonium 34 34 chrysorheus 34 38 cilicioides 34 19 cinereus 34 43 circellatus 34 26 coleopteris 34 24 comigis 34 oo croceus 34 31 Curtisii 34 41 cyathulus 34 40 deceptivus 34 13 delicatus 34 32 deliciosus 34 32 furcatus 34 18 Gerardii 34 52 griseus 34 4b helvus 34 44 34 54 hygrophoroides Indigo 3* ^^ insulsus ^^ lanuginosus 34 £o lentus 3^ ^^ ^4 7 pergamenus ^^ pipcratus '^^ 208 Journal of the Mitchell Society [March Lactarius agglutinatus — Continued vorv. page plinthogaJus 34 48 quietus 34 39 rimosellus 34 58 rusticanus 34 15 scrohiculatus 34 21 speciosus 34 29 subdulcis 34 59 sithplinthogalus 34 50 subpurpureus 34 34 subtorviinosus 34 18 subvellereus 34 10 tlieiogalus 34 36 torminosus 34 16 trivialis 34 23 turpis 34 28 vellereus 34 8 volemus 34 53 sp? 34 59 Land vertebrate fauna of North Carolina, some known changes, Brimley 32 17C Landslides, notes on their occurrence. Holmes 33 100 Lanneau, John Francis The sun's eclipse June 8, 1918: a ques^^ion 34 76 Lanneau, John Francis, 18361921 37 17 Lansing, N. C, magnetic-marble ore, Bayley 37 138 Lasley, John Wayne, Jr. Some elementary vector equations 32 143 A theorem on double points in involution 37 80 Laurel Oak, Coker 32 38 Leidy's Ouramocha and its occurrence at Greensboro, N.C., Gudger 32 24 Lithistid sponges, remarkable form of skeletal element, Wilson.... 36 54 McAtee, Walbo Lee Notes on the flora of Church's Island, NC 35 61 McGregor, Ernest Alexander List of plants from Batesburg, S.C, and vicinity 33 133 MacNider, William deBerniere On the occurrence and distribution of potassium in normal and nephropathic kidney cells 32 113 Magnetite-marble ore at Lansing, N. C, Bayley 37 138 Manina 34 176 cordiformis 34 176 flageUum 34 177 Markham, Blackwell Asymmetrical regulation in anuran embryos with Spina befida defect (with H. V. Wilson). Abstract 37 113 Maximal ease, Henderson and Baity 37 61 1922] Index to Volumes 32-37 209 VOL,. PAGE Memminger, Edward Eead A correction 32 120 Metcalf, Clell Lee List of Syrphidao of North Carolina 32 95 Metcalf, Zeno Payne. The age of insects 37 19 A portable printing press for the ecologist 35 20 Molluscan shells of Beaufort and vicinity, Jacot 36 129 Mosquito control, in relation to fishes, Hildebrand 37 161 Mosquito fauna of North Carolina, Sherman 36 86 Naematelia 35 134 eucephaliformis 35 137 nucleata 35 136 quercina 35 135 North Carolina Arborescent flora, Ashe 34 130 Butterflies, a key, Brimley 37 73 Collybias, Coker and Beardslee 37 83 Craterellus, cantharellus, Coker 35 24 Fisheries, Pratt 32 149 Herpetology, Schmidt 32 33 Hydnums, Coker 34 163 Laetarias, Coker 34 1 Land vertebrate fauna, Brimley 32 176 Lower basidiomycetes, Coker 35 113 Mosquito fauna, Sherman 36 86 Prunus umhellata, Holmes 34 126 Eats, mice and shrews, Brimley 35 55 Eeptiles and ami:)hibians, Brimley 34 148 Eussulas, Beardslee 33 147 Soil statistics. Harper 33 106 Syrphidae, Metcalf 32 95 Thelephoraceae, Coker 36 146 Turtles, Brimley 36 62 North Carolina Academy of Science Proceedings, 15th annual meeting, 1916 32 41 Proceedings, 16th annual meeting, 1917 33 89 Proceedings, 17th annual meeting, 1918 34 65 Proceedings, 18th annual meeting, 1919 35 1 Proceedings, 19th annual meeting, 1920 36 7 Proceedings, 20th annual meeting, 1921 37 6 Nyctalis 35 30 asteropliora 35 30 Oak from the Gulf States, new species, Sterrett 37 178 Opuntia Drummondii, on Smith Island, Coker 34 150 Ouramoeba, bibliography, Gudger 32 31 Leidy's, Gudger 32 24 210 Journal of the Mitchell Society [3Iarch VOL. PAGE Padina, alternation and parthenogenesis, Wolfe 34 78 Patterson, Andrew Henry The theory of relativity 36 19 FeniopJiora 36 158 albomarginata 36 160 cinerea 36 162 filamentosa 36 162 gigantea 36 159 longispora 36 161 mutata 36 163 violaceo-livida 36 160 Phaeotremella pseudofoliacea 35 150 Phellodon 34 192 alboniger 34 194 amicus 34 192 CoJceri 34 195 Ellisianus 34 196 tomentosus 34 194 Phrynosoma cornutum, Givler 37 130 Pitcher-plauts, American, Harper 34 110 Plants, effect of relative length of day and night on growth, Gaener and Allard. Abstract 37 108 Platygloca 35 122 caroliniana 35 123 Lagerstroemiae 35 124 Plicaturella 35 48 olivacea 35 48 Potassium in normal and nephropathic kidney cells, MacNideb.... 32 113 Pratt, Joseph Hyde Fisheries of North Carolina 32 149 Memorial sketch of Dr. Joseph Austin Holmes 32 1 Printing press for the ecologist, Metcalf 35 20 Protocoronospora nigricans 36 74 Prunus umbellatus, extent of range into North Carolina, Holmes.... 34 126 Pulmonary veins, an interesting anomaly, George 37 173 Quercus AsJici, Sterrett 37 178 Quercus Laurifolia Michx, Coker 32 38 Easpailia, the Genus, Wilson 37 54 Kats, mice and shrews, Brimley 35 55 Relativity, bibliography, Patterson 36 39 The theory, Patterson 36 19 Mhododendron catawbiense, distribution, Coker 35 76 Robinia, eastern shrubby species, Ashe 37 175 Rotundifolia grapes, pollination, Detjen 33 120 1922] Index to Volumes 32-37 211 VOL. PAGE Eussula 33 147 adusta 33 156 alhida 33 165 albidula 33 176 alutacea 33 193 aurantialutea 33 194 aurata 33 187 iasifurcata 33 188 cinerascens 33 164 compacta 33 158 crustosa 33 175 cyanoxantha 33 173 decolorans ^..... 33 169 delica 33 152 densifoUa 33 161 Earlei 33 160 emetica 33 163 flava 33 166 flavida 33 167 floccosa 33 161 foetans 33 180 fragilis 33 164 graminicolo7- 33 190 grisea 33 188 lepida 33 178 luteohasis 33 182 magna 33 183 magnifica 33 159 mariae 33 171 meliolens 33 170 nauseosa 33 191 nigricans 33 162 ochroleuca 33 103 olivascens 33 189 pcctinata 33 181 puellaris 33 186 pulverulenia 33 182 pungens 33 196 purpurina 33 156 pusilla 33 169 Eomcllii 33 192 ruhescens 33 183 sanguinca 33 177 subvelutina 33 190 tenuiceps 33 194 uncialis 33 155 variata 33 153 212 Journal of the Mitchell Society [March Bussula — Continued vol. page viresce7is 33 174 xerampelina 33 185 Eussulas of North Carolina, Beardslee 33 147 Saccoilastia 35 121 ovispora Moller var. caroIi)iiana 35 121 Sarracenia 34 112 Drummondii 34 121 flava 34 119 minor 34 117 psittacina 34 116 purpurea 34 114 rubra 34 117 Sledgei 34 118 hybrids 34 122 Schmidt, Karl Patterson Notes on the herpetology of North Carolina 32 33 Sclerotium Bolfsii Sacc, Higgins 37 167 Sehacina 35 156 calcea 35 157 Eelvelloides 35 159 incrustans 35 159 sp? 35 157 Septol)asidium 35 125 pseudopedicellatum 35 125 retiforme 35 127 Seliweinitzii 35 128 Septocladia, Coker and Grant 37 180 Sherman, Franklin Notes on the mosquito fauna of North Carolina 36 86 Shrubs and vines of Chapel Hill, Coker and Totten 32 66 Hirohasidiaccae 35 128 Sirohasidium 35 128 Brefeldianum 35 128 Small, John Kunkel The land of ferns: habitats and distribution of the fermvorts of Florida 35 92 Smith, John Eliphalet Diorites near Chapel Hill, N.C 33 128 Snuth Island, N.C, a visit, Coker 34 150 Soil statistics and their significance, North Carolina, Harper 33 106 Solenia 36 150 poriaeformis 36 151 South Carolina, regional geography, Harper 35 105 Sparassis "^^ ^^^ crispa 36 195 Eerlstii 36 194 spathulata 36 194 1922] Index to Volumes 32-37 213 VOL. PAGE Spirogyra, occurrence of unlike ends of the cells of a single fila- ment, Cunningham 3(3 227 Sponge species, Wilson. Abstract 37 112 Sponges, lithistid, remarkable form of skeletal element, Wilson.... 36 54 Sponges, some generic distinctions, Wilson 35 15 Sponges of Beaufort (N.C.), George and Wilson. Abstract 37 112 Steccherinum 3^ 278 adustum 34 jgQ indcherrimum 34 ^78 Rliois 34 279 Stereum 36 175 fasciatum 3q 280 frustulosum .* 3g 279 fuscum 3g 284 gausapatum 35 276 lobatiom 3g 28O ochraceoflavum 3q 283 rameale 36 181 sa7iguinoletitum 3(3 277 sericeum 3g 282 suhpileatum 3g 277 Sterrett, William Dent A new oak from the Gulf States 37 278 Syrphidae of North Carolina, list, Metcalf 32 95 Texas Horned Lizard, Givler 37 230 Theleplwra 36 280 alhido-hrunnea 35 291 cuticularis 3g 290 fimbriata 36 292 griseosonata 36 290 intyhacea 36 189 lutosa 36 192 multipartita 36 286 palmata 36 igg regularis 36 188 terrestris 36 289 'Viaiis 36 287 Thelephoraceae of North Carolina, Cokeb 36 146 Tintinnus serratus, occurrence, Cunningham 35 12 Totten, Henry Roland Shrubs and vines of Chapel Hill (with W. C. Coker) 32 QQ Trees of North Carolina, Ashe 34 130 Tremella 35 238 aspera 35 241 auricularia 35 142 214 Journal of the Mitchell Society '[March Tremella — Continiied vol. page carneoalba 35 146 corrugata 35 151 crassiloha 35 151 crenata 35 151 dependens 35 150 enata 35 149 frondosa 35 141 fuciformis 35 140 gigantea 35 149 lutescens 35 143 moriformis 35 148 myricae 35 150 palmata 35 151 pinicola 35 144 reticulata 35 139 rufolutea 35 149 stippitata 35 150 suhanomala 35 148 tremelloides 35 149 virens 35 145 Tremellaceae 35 129 Tremellodendron 35 153 aurantium 35 155 candidum 35 153 Cladonia 35 154 merismatoides 35 154 Tremellodon 35 152 gelatinosum 35 152 Trogia 35 29 crispa 35 29 Turtles of North Carolina, with a key to the turtles of the eastern United States, Brimley 36 62 Tuscaloosa County, Alabama, botanical bonanza, Harper 37 153 Vector equations, elementary, Lasley 32 143 Venable, Francis Preston Chemical behavior of zirconium 36 115 Chlorination by mixed carbon monoxide and chlorine (with D. H. Jackson 35 87 Industrial apj^lications of zirconium and its compounds 34 157 Isotopes 37 115 Joseph Austin Holmes 32 16 Luminescence of zircons 84 73 Vetch disease, one little knoAvn, Wolf 36 72 Vines and shrubs of Chapel Hill, Coker and Totten 32 Q& Vitis rotundifolia, Detjen 33 120 Water mold, new genus related to Blastocladia, Coker and Grant.... 37 180 1922] Index to Volumes 32-37 215 VOL. PAGE Wheelek, Alvin Sawyer The critical dyestuff situation 32 53 Juglone 35 49 Wilson, Henry Van Peters Asymmetrical regulation in anuran embryos with Spina bifida defect (with B. Markham). Abstract 37 113 The genus Easpailia and the independent variability of diag- nostic features 37 54 A glance at the zoology of today 32 83 In regard to species and sponges. Abstract 37 112 The nature of the individual in the animal kingdom 32 125 On some generic distinctions in sponges 35 15 A remarkable form of skeletal element in the lithistid sponges 36 54 Si^onges of Beaufort (N.C.) harbor and vicinity (with W. C. George). Abstract 37 112 Wolf, Frederick Adolph A little-known vetch disease 36 110 Wolfe, James Jacob Alternation and p.irthogenesis in Padina 34 78 Eeview: "A primer of household biology," by E. W. Gudger 34 154 Wolfe, James Jacob, 1875-1920 36 110 Published papers and addresses 36 113 Zirconium, chemical behavior, Venable 36 115 Zirconium and its compounds, industrial applications, Venable.... 34 157 Zircons, luminescence, Venable 34 73 Zoology of today, a glance, Wilson 32 83 Back Numbers of the Journal of the Elisha Mitchell Scientific Society Can be Supplied as Follows: t AT $0.50 PER PART Vol. 4, Pt. 1 Vol. 5,pt.l Vol. 6,pt.l Vol. 7,pts. 1&2 Vol. 10, Pts. 1 & 2 Vol. 11, pts. 1 & 2 Vol. 12, pt. 1 Vol. 13, pts. 1 & 2 Vol. 14, pts. 1 & 2 Vol. 15, pt. 2 Vol. 16, pts. 1 & 2 Vol. 17, pts. 1 & 2 Vol. 18, pt. 2 Vol. 19, pts. 1 & 2 Vol. 20, pts. 1, 3, & 4 AT $2.00 PER VOLUME Vols. 21-32 inclusive AT $3.00 PER VOLUME Vols. 33 to present time New York Botanical Garden Librar >« ;? y