standards of the Milton Bradley Co., as con- " Symmetric Binary Forms and Involutions," by tained in this book of Professor Mulliken's, Arthur B. Coble. it would be possible to accurately describe and "Systems of Tautochrones in a General Field identify the exact shade of the characteristic of Force," by Harry Wilfred Reddick. sample dyeings, without pasting a single "The General Transformation Theory of Differ- ential Elements," by Edward Kasner. sample in the book. And, by a proper system of classification, the chemist attempting to BOTrlNICAL NOTES identify a color, after determining its class, and dyeing a sample, would determine its ex- TWO REUENT BOOKS ON LIUHENS act place in the color table, and so avoid the WITHIN a few weeks of each other two necessity of hunting it up in the sample books notable contributions to our knowledge of the of the different color houses, or in his own lichens of this country have been issued. The sets of home-made samples. first is Albert W. C. T. Herre's "Lichens To be of real value, such a treatise should Flora of the Santa Cruz Peninsula, Cali- be written by a well-trained color chemist, fornia," published in the Proceedings of the thoroughly familiar with the dyestuffs of to- Washington Academy of Sciences (Vol. XII., day, from their practical side, and accus- No. 2) and bearing date of May 15, 1910; tomed to face, in his regular work, the many while the second is Bruce Fink's "Lichens of and varied problems in textiles,, paper-making, Minnesota " published ,in the Contributions pigments, food products and the like, which from the United States National Herbarium appear every day in a large dyeing laboratory. (Vol. 14, Part 1) and bearing date of June 1, The theoretical part of such a book could 1910. The first contains 243 pages, and the be easily obtained from the treatises we have second 256 pages, with 51 plates and 18 text- at present, including this one of Professor figures. They are both nominally local lichen Mulliken's. But the use of the color stand- floras, and judged by their titles alone might ard would give opportunity for identifying the be supposed to present a similar mode of shades with a minimum of trouble and ex- treatment. However a comparative examina- pense; and if the writer would incorporate tion of the two works shows a marked differ- some of the regular laboratory information ence between them. Thus while both accept about methods, and about the practical peculi- Zahlbruckner's general understanding of the arities of the different dyestuffs, their ease of lichens, the first author proceeds at once to dyeing, comparative fastness, special uses, the descriptive part of his book, evidently as- cost prices as compared to others of the same suming that the reader will bring to its or different classes, and a host of other minor perusal all the necessary knowledge for its matters of practical interest to users and full understanding. In Professor Fink's workers with the dyestuffs, such a book would book, on the contrary, there is an explanatory be hailed with enthusiasm by dyeing chemists introduction in which there is a discussion of from one end of the world to the other. the nature of lichens, and the views that have CHARLESE. PELLEW prevailed during the past two centuries. This Odober 6, 1910 is followed by a particular discussion of what NOIENTIFIC JOURNALN AND ARTICLEN is known of their structure and reproduction, including under the latter sexual reproduc- THE contents of the American Jouraal of tion. Here he says "the sexual processes Mathematics for October Are : have not been studied in very many of the " q-Difference Equations," by Rev. I?. H. Jack- son. fungi most closely related to the lichens, but "On the Relation between the Sum-formulas of recent discoveries seem to indicate that sex- IEilder and Ceskro," by Walter B. Ford. uality is common there and in the ascomyce- "Sur un Exemple de Fonctibn Analytique Par- tous lichens as well. In Collema, Stahl and tout Continue," pa% D. Pompeiu. others have found that the apothecium is SCIENCE [N. 8. VOL.XXXII. No. 826 preceded by an archicarp and a trichogyne covers an area more than forty times as large, which are supposed to constitute a reproduc- the number of species and subspecies is 441. tive tract. The more recent researches of We have no means for comparing the treat- Baur, Darbishire, Lindau and Wainio have ment of species and lower groups by the two proved the existence of similar tracts in authors, but from " the face of the returns " lichens of several genera, and while there is as here given it appears that the Santa. Cruz yet much need of research regarding nuclear peninsula must be more than ordinarily ricli behavior, the general presence of sexual or- in lichen forms. gans in lichens can scarcely be questioned Mr. Herre's book includes one new genus longer." and eleven new species, certainly not a great It need scarcely be said that both authors number for such an area, or such a total nurn- accept the duality of the lichen's structure as ber of forms. In Professor Fink's boolr we no longer to be questioned, which reminds the have been unable to find a single new species. writer of this review of the complete change These are encouraging sips. In some other of opinion in this regard that has taken place departments of systematic botany two such in the past thirty years. Then every Ameri- books as these could have been depended upon can and practically every English lichenol- to yield from 50 to 100 new species at the very ogist denounced the " algo-lichen hypothesis " least ! as they styled it, as the height of foolishness, In both books all specific names are de- as well as the depth of stupidity. Now one capitalized. Professor Fink's book is richly wonders whether there are any botanists who illustrated by 52 plates (mostly reproduction4 regard lichens as autonomous in the old sense. of photographs) and 18 text figures. Some of Are there any who deny that the " gonidia" these are exceptionally fine. are algs? Where are they who so vehemently denounced Schwendener and his little band of followers? Here we have a professed lichen- ITis not so very long since there were no ologist uttering such words as these : " What- plant pathologists in the United States. At ever may be the outcome of further study of least there were none Imown by that name. this question, the conception . . . which is There were a few botanists who began to real- still held by some botanists, that the fungus ize that plants were subject to diseases, but and the alga together compose an organism or the United States Department of Agriculture an association which constitutes the lichen had as yet given no attention to the subj~ct, need be abandoned before there can be any and this was before the inception of the ex- clear thinking regarding lichens. The lichen periment stations. At one time several botaii- is the fungus of the association." In the old ists united in a memorial to the Department days this would have been regarded as a be- of Agriculture calling attention to the de- trayal of lichenology, for logically it reduces sirability of beginning work in plant pathol- all "lichens'' to the category of fungi. In ogy, and what was their astonishment when the old days the paragraph quoted would have the secretary very promptly appointed Pro- brought down a storm of wrath upon the head fessor Scribner, until then a student of the of the author, but now no one notices this as grasses, to be the pathologist. And no one at all out of the ordinary. Ternpora mutan- was more astonished than the professor him- tur! self, but at that time secretaries of agricul- In Mr. Herre's book 307 species and sub- ture knew little or nothing as to the qnalifi- species are described from a peninsula 90 cations of a pathologist. And it is greatIy to miles long and including perhaps no more the credit of the graminologist so suddenly than 1,800 to 2,000 square miles, and ranging torn from his chosen speciality and thrust from sea level to a maximum elevation of into a new field, that he started the work in a 3,793 feet. In Professor Fink's book which creditable manner, and laid a good founda- SCIENCE tion for the excellent work that for many Hall's book also will be quite easily under- years has been done in the department. stood, especially by farmers of some botanical These thoughts are suggested by the fact education. Its classified host arrangement that there lie before the writer three notable will prove especially helpful to this class of recent books on plant diseases, by American readers, and will appeal to many students authors. They are Duggar's "Fungous Dis- also. Duggar's book is especially a mycol- eases of Plants " (Ginn), Selby's "Handbook ogist's book, since the fungous parasites are of the Diseases of Cultivated Plants in Ohio " taken up in their natural sequence. It is the (Ohio Expt. Stn.), and Stevens and 1Iall's most technical of the three books, and for that "Diseases of Economic Plants " (Macmillan). reason will appeal most strongly to the teacher The first of these treats the subject from the and student who approach the subject from standpoint of the parasite, so that in it the the mycological rather than from the agri- student of the fungi may learn what injury, cultural or horticultural side. if any, is wrought by any fungus, or group of fungi. Two hundred and forty illustrations, POISONOUS PLANTS many reproductions of photographs, help to PROFESSORDOCTORPAMMELhas brought out make the text clearer for the beginner. A a most useful book under the title of " A Man- "host index" brings together the various par- ual of Poisonous Plants " (Torch Press, Cedar asites that affect particular $osts. Rapids, Iowa). After a general discussion The second book is a revision and enlarge- of the nature and action of poisons the au- ment of a most useful bulletin (121) issued thor presents a systematic catalogue of the several years ago. In it, after an introduction plants that are poisonous, beginning with the treating of plant diseases in general, the bacteria and blue-green algae, and running up subject is treated from the standpoint of the through the flowering plants. The illustra- hosts alphabetically arranged. Thus we have tions, of which there are a hundred or more, alder diseases, alfalfa diseases, apple diseases, will prove helpful, especially for the non-bo- and so on throughout the alphabet, to water- tanical reader. The book will be useful to melon and wheat diseases. Good illustrations physicians and medical students, as well as (105) are scattered through the text. to farmers who may wish a guide as to the The last book to appear is the result of many nature of many of the plants about them, years of work by the senior author. Here the while it will be interesting and helpful to the treatment is from the standpoint of the hosts, general botanist also. but instead of taking these up in a simple alphabetical order, they are alphabetically ar- ranged under certain general heads, as poma: A NEW MUSHROOM BOOK ceous fruits, drupaceous fruits, small frpits, A NEW type of mushroom book has just been tropical fruits, vegetable and field crops, cer- brought out by Professor Doctor Clements eals, forage crops, fiber plants, trees and under the title of "Minnesota Mushrooms." timber and ornamental plants. More than It is the fourth of a series of popular guides two hundred text figures add greatly to the to the plants of Minnesota to appear in the usefulness of the book. Some of these are ex- well-known Minnesota Plant Studies, and is ceptionally fine reprod~xctionsof photographs. designed for the use of classes in the high American botanists are to be congratulated schools, and as a guide to make available the upon the publication of these three books. edible species by distinguishing them with They will serve as most valuable helps in in- certainty from those which are harmful. troducing students to the outlines of plant Copies of the book "are furnished free to cit- pathology. Selby's book is the most "popu- izens of Minnesota upon request " and '' ten lar" and will be most easily understood by copies are sent free to each high school, acad- farmers, and general students; Stevens and emy, or college within the state." Certainly 8cIEAVl8 [N. S. VOL.XXXII. No. 826 the inhabitants of Ninnesota ought not to be pleted a voyage of nearly 7,000 miles since she in ignorance hereafter as to the mushroom left last June and is now at the mouth of the species of that state. Amazon Itiver. The present voyage has not The book opens with an introductory page only cut across our first cruise, but is so ar- of generalities regarding fungi, among which ranged, by the introduction of loops, as to we are glad to find that the Roman pronuncia- intersect itself also at various points. We are tion of the Latin names of families, genera thus enabled to apply numerous checks. and species is given as the proper one to be In addition, special observations have been used. Then follows keys and descriptions, made in Gardiner's Bay, of1 Long Island, and accompanied by 124 reproductions of photo- on the neighboring islands at the beginning graphs. The attempt has been made by the of the first cruise in September, 1909, and author to write his descriptions in such non- again at the beginning of the present cruise technical language as will render them intel- in June of this year. The results of all these ligible to the reader who is not an expert in elaborate tests have shown conclusively that, mycology. Even the non-botanical reader will with a non-magnetic vessel like the Ca~negie be able to master the necessary terms by re- and with tho instrumental appliances and ferring to the glossary at the end of the vol- methods used, it is possible to secure an ac- ume. Four color plates add to the interest curacy in the magnetic results approaching of the book. The last chapter deals with col- that of land observations. lecting and cooking mushrooms. Enough As I am to cover four lines of activity on advice is given here to prevent any danger this vessel in the space of a quarter of an hour, from the use of poisonous species, and there it will not be possible to go into further detail are enough recipes to start out the neophyte and I shall have to content myself with statiirg mycophagist happily and safely. at once the main conclusions reached. CI-IARLESE. BESSEY A. Terrestrial Magnetism.-Except for the THEUNIVERSITYOF NEBRASKA portion of the cnxise froin 4S0.5 N., 47' W. to Falmouth Bay and thence to Madeira, all THE SCIENTIFIC RESULT8 OF THE FZRXT charts show too low west magnetic declination CRUISE OF THE "CARNEGIE" IN MAB- over the portion of the Atlantic Ocean covered NETISM, ELECTRICITY, ATMOSPITERZC by the Carnegie. While the correction is in REPEACllION AND OlZAVITY general less than a degree, it is unfortunately THE first cruise 01 the Carnegie began at in the same direction for about 5,000 miles, Brooklyn in August, 1909, and ended at the and hence the resulting error in a ship's course same place in February of the present year. based on the present mariner's charts may be During this period of about six months, a accumulative and ultimately reach a consid- total distance of 8,000 nautical miles was cov- erable amount. The maximum chart error at ered in the north Atlantic Ocean between the any one point may be from 1°.3 to 2O.6 ac- parallels 51' north and 19' north and the fol- cording to the chart used. lowing ports were visited: Greenport (Long The chart corrections both for magnetic in- Island), St. John's (Newfoundland), Fal- clination and horizontal intensity, often being mouth (England), Funchal (Madeira), Ham- of opposite signs on the portion of the Car- ilton (Bermuda) and Brooklyn (New York). negie's first cruise, the average algebraic cor- Last June the vessel started out once more, rection is in consequence at times greatly re- this time on a circumnavigation cruise of duced. The average chart correction (sign 66,000 miles to extend over a period of three not being considered) for magnetic dip ap- years and to embrace the Atlantic, Indian and proximates 1°.5 to 2'; the maximum correc- Pacific Oceans. The vessel llas already com- tion for the British chart is 2O.5 and that of Read at the meeting of the American Physical the German 4O.4. It is also seen from the Society, New York, October 15, 1910. values of the average algebraic dip correction!