NATURE VOL. 226 APRIL 25 1970 383 zoologist as well as the specialist in fish physiology". I QUANTUM CHEMISTRY think it will, and I expect that it will be found in all relevant libraries, in spite of the heavy price that has to Methods of Molecular Quantum Mechanics be paid. C. E. LUCAS By R. l\foWeeny and B. T. Sutcliffe. (Theoretical Chemis­ try-A Series of Monographs, Vol. 2.) Pp. ix+307. (Academic Press: London and New York, December 1969.) Sis; $13·50. \VRITTEN for a far more sophisticated and exacting reader­ NEW WORLD FLORA ship than the first volume in the series, this is a book in which even the most experienced quantum chAmist should Vascular Plants of the Pacific Northwest find a great deal of value. A rigorous yet economical Part 1: Vascular Cryptogams, Gymnosperms, and Mono­ exp::>sition, characterized throughout by refreshing critical cotyledons. By C. Loo Hitchcock, Arthur Cronquist,, insight, it has all the qualities one would expect of its Marion Ownbey and J. \V. Thompson. Pp. 914. (Univer­ authors. sity of Washington Press: Seattle and London, November Being designed "for students specializing in theoretical 1969.) 238s; $25. chemistry or molecular physics", it uses techniques which THE recent publication of part one now completes this go well beyond the repertoire of the average chemist. It is magnificent and already well known flora, the other four certainly a work of consolidation rather than primary parts (each worthy of being called a volume) having instruction. At first sight, much of the analysis will seem appeared in reverse order during the past fifteen years, formidable to student readers; and, while those who do starting with Cronquist's Compositae. battle with the difficulties will find themselves very well The Pacific North-\Vest, as defined by the authors of rewarded, I think this book will probably be more popular the flora, is an extensive area of territory covering the with teachers of quantum chemistry than with their states of Washington, northern Oregon, Idaho north of students. the Snake River plains, the western mountainous part of Together with two appendices, the first two chapters Montana and southern British Columbia. Some 4,000 present a brisk survey of tho general principles and species of vascular plants are known to be indigenous here theorems of wave mechanics, illustrated by reference to or to have been introduced and these have now been fully one- and two-electron systems. Next comes a careful dealt with in the five parts. As the title indicates, part account ofthc various op;rators used in formulating many­ one includes the vascular cryptogams (ferns and fern electron antisymmetrized wave functions. allies), gymnosperms and monocotyledons, most of them Having completed the usual preliminaries (though by dealt with by the senior author C. L. Hitchcock. Users of no means always in the usual way), the authors then this and probably the other parts of the flora may possibly provide a most welcome discussion of electronic charge be confused by the circumscription and nomenclature of distribution, including, of course, a description of density the divisions and classes of the higher plants. For instance, matrices. here the name Pinophyta is used for Gymnospermae, The next three chapters deal in turn with the Hartree­ Magnoliophyta for Angiospermae and Liliatae for Mono­ Fock theory and its principal elaborations, with valence­ cotyledonae, following the recent proposals of Cronquist bond theory, and with various recent developments et al. in Taxon, 15, 1966. The sequence of monocotyledon (generalized product functions; variation-perturbation families also follows Cronquist's Evolution and Glass,i.fica­ theory for group functions; cluster development; corre­ tion of Flowering Plants (1968) and might seem strange to lated pair functions). those not already familiar with this treatise. Besides the A chapter on electrical and magnetic effects is supple­ usual keys to fa';uilies, genera and species and rather full mented by a quite substantial appendix dealing with descriptions, complete "regional" synonymy is given relativistic terms in the Hamiltonian operator. together with details of chromosome number (very The book concludes with a description of some typical frequently known), "genuine" vernacular names and molecular calculations. This is the only chapter in which infmmation on distribution and ecology. Finally, notes any numerical results are discussed. on infraspecific variation have been added. Following It could perhaps be argued that much of the material the (unfortunate?) tradition of most temperate floras, no in this book could have been expounded accurately and matter how elaborate, no specimens are, however, cited effectively in a simpler way; but this was clearly not the other than type material. authors' intention, and they are to be congratulated on Perhaps two features above all contribute to the useful­ producing a contribution to the didactic literature of ness of this particular part. The first of these is the quantum chemistry that is really distinctive. excellence of the illustrations by J. R. Janish. Practically E. THEAL STEWART every species has been illustrated by simple but extremely clear and accurate line drawings, depicting habit and diagnostic characteristics. The second is the inclusion of special keys. One to the grasses of the area ( again illustrated) is based purely on vegetative features and will be of great potential use to pasture ecologists and Obituaries agriculturists who so often must, of necessity, identify sterile material. There is also a key to aquatic plants (all Dr Peyton Rous vascular groups included), again chiefly on vegetative ExPERil\IENTAL pathology and cancer research, and characters. indeed the whole of biological and medical science, have This volume, being the last and largest part of the flora sustained immense loss from the death, on February 16, to appear, includes several sections relating to the work 1970, of Francis Peyton Rous, at the age of 90. His as a whole. There is, for instance, an index to all the special fields will never be the same without him. Yet our plant families, a glossary and a corrigendum to the other main emotion must be of gratitude for his long life and parts. Finally, there is a complete index to vernacular, epochal contribution. generic and specific names. Rous's mother was descended from Huguenots who had The sheer bulk of this flora means that it will serve aettled in Virginia after the Edict of Nantes; and his chiefly as a work of reference, but tho thoroughness of father was a Baltimorean of English forebears. Reading its production will certainly ensure for it a status and of his early life evokes and recaptures in remarkable value far above that of a mere regional flora, for many degree the spirit of a great period in the history of the years to come. BRIAN T. STYLES United States and. a little later, that of an outstanding

© 1970 Nature Publishing Group 384 NATURE: VOL. 226 APRIL 25 1970 phase in American medicine during the early yea1·s of tho century. After graduating MD at tlrn Johns Hopkins Medical School in 1905, Rous's interests very early turned to resean:h, with a period at Ann Arbor under Wart,hin and later in the Rockefeller Institut,e , New York, where he spent the groat part of his working life in the most happy and congenial of conditions. His move to the Rockefeller was a stroke of genius on the part of Simon Flexner, who accorded him oompleLe freedom and every encouragement., a privilege which Rous thenceforth ever valued and later recorded on many occasions. Between 1907 and l!JlO Ron8 made a wonderful start, wit-Ii papers on lymphocyte physiology, haematology, the COJ.'ebrospinal fluid and tissue transplantation. Very soon there ca.me tho stroke of fate. In the words of O. H. RobNtson, "One clay a chicken fancier came in to Hous's laboratory bringing a fowl with a large lump on its leg. Concerned for his flock, this man had taken the fowl to several unresponsive pathologists. Rous saw that the lump was a tumour and in a class of animals unstudied in such relation". The tumour proved t,o be a spindle-ctoll sarcoma, which Rous was able to t.ransmit to other fowls of thto same inbred stock, not only by grafoing but also Dr Peyton Rous through the injection of cell-free filtrates. The times must have been propitious, following Ellermann and .Bang's and highly productive phase which endured to the end of descript,ion of an apparent leukacmitt virus in 1908; yet his life. Of special and lasting value were his studie;; of Hons's di;;covery was a monumental and key event in the the biological interactions beLween chemical carcinogens history of cancer research. a nd neoplastic viruses, and the generation of highly The Rous agent, as it came t,o be called, also Reemed malignant carcinornata in the rabhit on t.he basis of the­ to ho viral in nature, with extraordinary specificity in viral papillonms. In part, this experimental ·work led to. t,ransforming normal cells into the exact replica of the and was intertwined -with, a fundamental conception (with sarcomtt cells from which it was derived. Later, Rous Friedcwald) which ranks, in the view of many, a.s perhaps and his co-workers imcovflrtod other avian oncogenic the most profound of Rous's con1,ributions; namely, the vimses, each again with its own individual transforming dissection of t.110 carcinogenic process into two main stages property. Especially wit.h J. n. Murphy, Rous studied of initiation and promotion. Independently advocate>d tho growth of such tumours and viruses in the avian by Borenblum, the hypothesis remain,- influent.ial and ma~­ cmb1:yo, perhaps the earliest use of this technique, and an s(,ill receiYc its explanation in chemical and CJ-tological exmnplo of the freshness and originality which cha,racter­ terms, izcd so much of his work and still exert their influence. At the time of the discovery of the avian tumour There is evidence that these discoveries were not. perhaps ,,iruses, and for several decades thereafter, technical fully appreciated at the time, as was seen from a species resoul'ce;; were imtdcqnato to penet,rat,e their structme and of metaphysical pathology on the part of the orthodox, biochemistry, Although much remains t.o be done, great according to which the tumours, although s,i,rcomata, advances arc in prospect which might clranrntically or could not be tumours since t,hey were virus-induced. even decisively illumine the whole of the cancer problem. Rons was also disappointed by his failure, aftor strenuous Meantime, in his later years .H.ous experienced great­ efforts, to demonstrate any kind of viral transmission of excit,ement from many discoveries on the part of others cancer in mammals. For somo fifteen years he then spent demonstrating t,hc unexpected qualit,y of the Huus virus, his energies in more physiological pursuits, and this enhanced or in association with other agents, to break the period embraced a wido variety of classical papers. species barrier and to evoke tumours in many species, Outstanding topics wore the preservation and transfusion both c1,vian and mammalian; and secondly, from the of blood, with practical application in both tho First and immonso rosnrgence of tumour virology to which his lone Second World Wars by means of tho Rous- Turner formula; observation of 1910 had pointed the way. the geno,;is of gallstones and the relation of blood destnw­ Aside from his own publin1,tions (some 300 in all) Rouc; tion to bile pigment output; live1· function in many also contributed to scientific prcson(,11-t.ion and acted as aspects; and the rneasul'ement of hydrogen ion concen­ editor of the Journal of Experimental Medicine for on' l tration in living tissues. Throughout his work Rous thirt.v years. His width of cultivation could also be seen showed .n.u·c 1,echnical ingenuity, perhaps the most, famous in n;ost amusing and lighthearted <'~flays, as on tactless­ inst,,1nco being his isolation of Kupffer cells in pure ness, and tho lamentable decline in self-satisfaction. culture by loading them with particulate iron and collect­ Honours descended upon him from every part of the ne,r ing them from liver perfusatcs with the aid of a magnet. world and tho old, culminating in the Nobel Prize few Another instance ahead of its time was his plating method Medicine (jointly) in J 966. Fol' rnn,ny reasons of clomos­ for individual cells. ticity and friendship he had special ties of affection for Rous's wholehearted and enthusiastic roturn to the England and, with much other recognition, treasured hi,;; cancer field was prompted by two personal episodes. A Linacre lectureship at Cambridgo, his honorary followship fow years before, W. E. Gyc had ID11do certain claims as of Triuity Hall, the Walker Prizo of the Royal College of io the constitution of the Rous a.gent. Although these Surgeon,;, and his foreign membership of Uie Roy<1l claims were not confirmed, their investigation had tho Societ,'. In admiration he would refer to "those wonder­ undoubted effect of bringing the filterable sarcomata into a ful po~vder-blue volumes" (the Scientific Reports) of the:, new prominence, an.cl through this development Rous was Imperial Cancer Research Fund. both encouraged and stimulatod-somot,hing for which he Rous was a tnte worker at tho henoh, yet believed that always expressed much gratitude. Secondly, the late the experirnent,al pathologist and the artist have much in Hichard E. Shope had persuaded Rous to ombark on a common. He described his recreation as "relishing life", full-scale investigation of t,hc so-called Shope rabbit and this he did to tho full. \1/hen the historv of cancer papilloma virus recently discovered in the cottontail research comes to be written, he will rank with.the highest rabbit. Hence it came that Rous entered a quite new in honour. -

© 1970 Nature Publishing Group