however, must be applied to the apple-grain species to which we are in this country giving

the name avenæ.

In Europe it is known that the name avenæ is a synonym of padi L. and that the primary host of the oat aphis is the bird cherry from which it migrates to grains and grasses. Avena is, however, employed here for the species living upon the apple. To use the names correctly then padi L. should be applied to our apple-grain aphis. But this would not be correct, for padi winters on cherry and migrates to grass. It is evident that our species is not padi.

Fitch described a species on choke cherries under the name of cerasifolia. This species curls the leaves of the cherry and suggests the work of padi in Europe. Transfers made by the writer prove that this species alternates between chokecherry and grasses in the same way that padi migrates in Europe. It is not impossible that they are the same species. We have then to deal with this species also on grains and grasses in the avenæ mix up. It is noteworthy that the cornicles of the chokecherry species are sometimes slightly swollen in a way similar to those of the common oat aphis. The second fork of the wing is also very close to the margin of the wing and rusty patches are present at the base of the cornicles of the individuals feeding on grains and grasses.

Some authors have expressed the opinion that our apple-grain insect is biennial. The experiments conducted by W. F. Turner and the writer prove that it is annual. It is not improbable that the difficulty in transfer arose, in that more than one species was concerned and that the apple was in reality not the winter host of the specimens transferred.

From the evidence in hand it appears:

1. That more than one species occurs upon grains and grasses under the name avena Fab.

2. That one of these species migrates to apple

and related trees where the eggs are laid. This species must be known as prunifolia Fitch.

I SHOULD think that the New York newspapers would be as tired of me as I am of them. As, however, you have devoted another editorial article to Columbia University and to my case, I beg permission to state certain facts.

My relations with the university were not considered by the department or faculty of which I was a member, or, contrary to your statement, by any faculty committee. At a meeting of the Columbia trustees on March 5 a resolution was introduced retiring me on account of a frivolous but truthful remark that I had made concerning the president of the university in a confidential letter to members of the Faculty Club. At the same meeting of the trustees a committee was appointed to ascertain whether doctrines contrary to the Constitution and the laws were being taught or disseminated at Columbia.

This latter resolution raised a storm of protest, the faculty of political science voting that it "betrays a profound misconception of the true function of a university in the advancement of learning." After passing resolutions of protest, the council, itself primarily an administrative body, appointed a committee of nine to defend the interests of academic freedom. This was not a committee of the faculty, but a Butler-Seligman committee, containing six deans, who are appointed by the president, and, according to the statutes of the university, must "act in subordination to the president.” From this committee Professor

Dewey has recently resigned as a protest against the general situation.

The resolution retiring me was referred to the committee, which unanimously recommended that no action be taken. They, however, asked me for an apology for my ironical remark about the president, and I signed the statement which Professor Seligman wrote, on the assurance that this would be of great service to the committee in maintaining the rights of the faculty and of freedom of speech, and on the promise that it would be shown to no one except the committee on inquisition of the trustees, and only to them if necessary. When the apology was sent out by Professor Seligman to officers of the university and printed in the newspapers I wrote a letter to members of the Faculty Club telling how it had been obtained. I thought I owed this to them, as many had approved of my remark about the president, one professor, for example, having written: "Let me first of all thank you for saying so well some of the things that I and many others dare not say for fear our families would be left without support if we did say them."

Professor Seligman then wrote a letter to me, copies of which he sent out by the hundred, stating that I did not "respect the ordinary decencies of intercourse among gentlemen " and that my "usefulness in the university has come to an end." As I understand it, Professor Seligman claims that he only broke the promise of a gentleman and I had no right to reveal the fact. I hold that it was the promise of the acting dean of the graduate faculties and of the chairman of the committee of nine of the council, made officially in the dean's office, and that secret diplomacy should have no place in a university.

Whatever may be the rights and wrongs of this petty squabble, seven of the nine members of the Butler-Seligman committee on June 18 recommended that I be retired from active service with the pension due me. The trustees, however, chose to dismiss me for maintaining academic freedom in the classical sense, not for resisting academic slavery as it exists at Columbia.

When they dismissed me on October 1, without a hearing, without payment for the year and without the pension due me, it was on the sole ground that I had on August 23 addressed a letter to members of the Congress asking them to support a measure then before the Senate and the House to prohibit sending conscripts" to fight in Europe against their will.” There is no law requiring or permitting the President to send "conscientious objectors" to fight in Europe. To do this, according to an opinion prepared by the Attorney General of the United States for the President in 1912, would be unconstitutional. It is also against the uniform policy of the nation. It would provide a less efficient army and might cause disorder at home. The British government does not require "conscientious objectors" to fight, and does not force conscription on Ireland. I only exercised the constitutional right and fulfilled the duty of a citizen in petitioning the government to enact legislation which I believe to be in the interest of the nation. By a curious irony the committee of the trustees appointed to guard the Constitution recommended my dismissal for using the method which the Constitution states shall not be abridged in a letter written to members of the Congress asking them to respect the Constitu

tion.

If the president and the trustees could have found in anything else that I have said or done anything that by any possible perversion could have been made to appear unpatriotic they would have been only too glad to have adduced it. As it is, they have hid behind the flag to assassinate, relying on the prejudice and blind patriotism of war. They might have retired me for insubordination, and there would have been no public protest; but they apparently wanted to injure me and discredit my efforts for university reform. This they may have been able to do, but only by causing at the same time far greater injury to the university.

I favor peace on the Russian terms, practically adopted by the President in his reply to the Pope. But both before and since our entry into the war I have done everything in

my power to promote national efficiency. I spent a large part of the week before I was dismissed drawing up for the War Department plans for the scientific selection of aviators. My oldest son, with my approval and assistance, was one of the first to enlist in the army and go to France, where he is in charge of sanitation in the Harvard hospital recently bombed by German aviators.-J. McKEEN CATTELL in the New York Tribune.

SCIENTIFIC BOOKS Algae. Volume I. Myxophyceae, Peridiniem, Bacillaries, Chlorophycea, together with a Brief Summary of the Occurrence and Distribution of Freshwater Algæ. By G. S. WEST, M.A., D.Sc., A.R.C.S., F.L.S., Mason Professor of Botany in the University of Birmingham. Cambridge, The University Press, 1916. G. P. Putnam's Sons, New York. $7.50.

The first volume of the series, to be issued as the Cambridge Botanical Handbooks under the editorship of Professor A. C. Seward and A. G. Tansley, of the school of botany of Cambridge University, is Professor G. S. West's volume on the "Alga." A life-long interest in, and an ever-increasing acquaintanceship with the extraordinarily diversified and numerous organisms embraced within the scope of this work have qualified this leading British algologist to undertake this task. For many years father (the late William West) and son have collaborated in the publication of a long series of memoirs and monographs dealing with the microscopic flora, not only of British waters, but of those of many other lands also. The critical knowledge thus acquired of the very large number of genera and species of algæ, mainly microscopic, has made possible this scholarly and well-proportioned treatise.

Dealing as it does with the Protophytes, the work is of especial interest, not only to botanists, but also to zoologists, especially protozoologists, who have long felt the need of a work more comprehensive in scope and succinct in treatment than Oltmann's Algen," Chodat's "Algues Vertes de la Suisse," or the authors' "Treatise on the British Freshwater

Algae," and more critical, the Lemmermann's useful handbooks of the Brandenburg Algae. Professor West's work adequately supplies this need. Since the work includes the Dinoflagellata (Peridinies) and the Volvocida (Volvocines) flagellates familiar to all zoologists and prominent in our text-books, the reviewer takes this means to call the attention of all zoologists and of biologists generally to the mine of information contained in this work. He shares with the author the opinion that the Flagellata are a primitive group and therefore of exceptional significance to all who seek the beginnings of either the plant or the animal world, and especially to students of sex, reproduction, variation, and the processes of evolution. It is noteworthy that the classification of green algae adopted by the author and the criteria of their chief subdivisions are based upon flagellate affinities.

It is perhaps natural that Profesor West's investigations of the Phytoplankton should have convinced him that most flagellates are holophytic and that ninety per cent. of the Dinoflagellata "are true vegetable organisms with a holophytic nutrition," but students of parasitic flagellates will demur from the first conclusion. In the reviewer's experience there is abundant evidence that the Gymnodinioida, or the most primitive section of the Dinoflagellata, the most abundant flagellates of the sea, are predominantly holozoic, and some are even cannibalistic, while many of the deep water species are undoubtedly saprophytic.

The author's conclusions regarding polymorphism among the algae, especially the Chlorophyceae, will interest all students of variation and evolution. Professor West has been a champion of the view of specific stability among the unicells, as over against the view of a wide polymorphism advocated by Chodat, Playfair and others. The results of the pure culture method in the hands of Klebs, Beijerinck, and others, have in the main supported the conclusion that specific stability is quite as constant among the algae as it is among higher plants. It is doubtless true that much of the so-called evidence for polymorphism has rested upon misjudgment as to the rela

tionships of convergent types commingled in a common environment and has no basis in critically conducted pure cultures. On the other hand, it is certainly to be expected that more instances of polymorphic life cycles, both obligatory and adaptive, will be discovered when the full histories of green unicells are unraveled. Furthermore, among the Dinoflagellata with certainty, and possibly among the desmids also, there is a high degree of self-regulating control of surface structures leading to a considerable range of form within the species. This is made evident from the fact that in both of these groups there are many species in which at the time of binary fission the daughter organisms each inherits one half of their exoskeleton or cell wall and forms the other half under the influence of the circumambient environment, which in some instances induces a strikingly different form of cell wall, involving structures utilized as specific characters. These may be of a mutative category, or more evidently of an adaptive or self-regulatory nature. It is also true that the theca or exoskeleton of the Dinoflagellata is subject to autotomy, local ecdysis, total exuviation, and local resorbtion and reconstruction to a considerable degree, after its formation, in adaptive response to changing environmental conditions. Such changes are not, however, of the same order of magnitude as those more profound ones occurring in the transformations in the life history of algæ, such as the Palmella stage of the Chlamydomonads.

On the whole, Professor West's contention as to specific stability seems to be well founded, provided adequate latitude for the metamorphoses of life history is retained and due allowance is made for adaptive and involution stages arising under environmental pressure. Both the pure culture method and wide observation of much material of the species under varying environments are needed to determine the normal range of form.

The rapid growth of biological literature in the past decades has tended to isolate botanists and zoologists, to the detriment of progress in both fields. Professor West's work is

of great value in facilitating excursions of zoologists into one fundamental and suggestive field of botanical research.

CHARLES ATWOOD KOFOID

ZOOLOGICAL LABORATORY,

UNIVERSITY OF CALIFORNIA

A German-English Dictionary for Chemists. By AUSTIN M. PATTERSON, Ph.D., editor of chemical terms for "Webster's New International Dictionary" and formerly editor of "Chemical Abstracts." New York, John Wiley & Sons, Inc.; London, Chapman and Hall, Limited. 1917. Pp. xvi + 316. Price $2.00.

Dr. Patterson's dictionary fulfils a need which probably every English-speaking worker in chemistry has experienced, and fulfils it admirably. The large number of scientific and technical words and the abbreviations which puzzle the beginner in the reading of chemical German are all there and the older chemist long accustomed to the reading of German chemical literature will experience no less satisfaction in the use of this book, for it is sure to save him much time in determining the exact meaning of the words that even he is apt to find troublesome. The thoroughness with which the dictionary covers the broad field of chemistry as well as such related sciences as physics, mineralogy and pharmacy is very satisfying. Since its appearance in January it has been in constant use in the office of Chemical Abstracts, where translating work involving every phase of theoretical and applied chemistry is done and it has stood this test of completeness in such a way as to justify the confidence with which it is used. I say "justify" because, knowing the nature of Dr. Patterson's work on other things and having in mind his experience in handling chemical literature and in compiling the chemical vocabulary and other parts of the New International Dictionary, we expect much.

In his translations of German names of chemical compounds Dr. Patterson has used care to keep the nomenclature in accord with the best usage. The Introduction, which should be very helpful in several ways, in

cludes interesting sections on inorganic and organic nomenclature. Many American chemists should read and heed the translating rules contained in these sections, for all too often German spellings, especially endings, are carried over into names used as English. At times this results in confusion. The new dictionary will tend to correct this bad practise, and it is hoped that it will help the cause of good chemical nomenclature in other ways.

Besides words from fields of science related to chemistry the dictionary contains a general vocabulary "to save the user the trouble of looking up the more common German words in a separate dictionary and "because many general words have a technical, or at least a customary, chemical meaning," which "in a general work is often either absent or buried among other senses." The entries are all brief, few of them requiring more than a single line (two columns to the page). There are no long paragraphs of combinations, examples, etc., to wade through. The English equivalent usually sought by the scientist is given at once. These features add greatly to the convenience in use.

The use of small type (six point), which does not seem objectionable since one does not read a dictionary steadily, has made for compactness. The book will fit a large pocket. The work of the printer and binder (the cover is flexible) has been well done.

It has been shown that the relative intensity of the different orders of an X-ray spectrum line depends upon the distance of the electrons from the middle planes of the atomic layers in the diffracting crystal.1 Imagine X-rays to be reflected from the surface of a ferro-magnetic crystal composed of atoms of the type just described. When the crystal is unmagnetized the different atoms will have their electronic orbits distributed in all possible planes, so that on the average the electrons will be at an appreciable distance from the mid-planes of their atomic layers. If, however, the crystal is magnetically saturated perpendicular to the reflecting face of the crystal, the electronic orbits, being perpendicular to the magnetic axes of their atoms, will all lie parallel to the crystal face. The electrons will therefore now be in the midplanes of the layers of atoms which are effective in producing the reflected beam. It can be shown that such a shift of the electrons must produce a very considerable increase in the intensity of the reflected beam of X-rays. On the other hand, if the crystal is magnetized parallel to the reflecting face, the turning of the orbits will carry the electrons farther, on the average, from the middle of their atomic layers, and a decrease in the intensity of reflection should result. Of course if the electrons are arranged isotropically in the atom, or if the atom is not rotated by a magnetic field, which would mean that it is the electron or the positive nucleus that is the ultimate magnetic particle, no such effect should be observed.

We have hunted in vain for such an effect on the intensity of the reflected beam of X-rays when the reflecting crystal is strongly magnetized. In our experiment a "null method" was employed. The ionization due to the beam of X-rays reflected from a crystal of magnetite was balanced against that due to a beam reflected from a crystal of rock-salt, so that a very small change in the relative intensity of either beam could be detected, while variations in the X-ray tube itself had little effect. 1 A. H. Compton, Phys. Rev., 9, 29 (1917).