American geographies like that of Payne (New York, 1798) commonly included sections on the globes. Payne discusses (Vol. I, pp. xxxiii-xxxviii) "Problems performed by the globe; Jedidiah Morse (American Geography, 3d ed'n, Boston, 1796) gives a tenpage discussion, with problems, on both Terrestrial and Celestial globes, and the same space is devoted to this topic in the first American edition (Philadelphia, 1794) of Guthries's Geography. It is worthy of note that David Rittenhouse contributed to the astronomical portion of the American edition.

The first astronomical book printed in America was the "Phisica, Speculatio . . Accessit compendium sphere Campani," by Alonzo de Vera Cruz (Mexico, 1557). An examination of this work and later Mexican works in astronomy and geography would be likely to reveal some use of globes in Spanish America.

These notes are intended to indicate some of the various sources of information concerning early American uses of the globes and also their intimate connection with early astronomy and mathematics in the New World.

UNIVERSITY OF MICHIGAN

L. C. KARPINSKI

ON THE EXCRETORY APPARATUS IN

PARAMECIUM

CERTAIN observations1 on the morphology of the contractile vacuole and feeding canals in Paramecium caudatum warrant the following conclusions:

The pore, contractile vacuole and canals (eight to eleven in number) form a continuous, permanent ectoplasmic structure. There is here, therefore, neither evidence of nor necessity for a sol-gel reversibility of the cytoplasm, as set forth by Taylor ('23) to explain the mechanism of the contractile vacuole in Euplotes.

In a longitudinal section through the cortex, at right angles to a perpendicular line drawn through the pore to the bottom of the vacuole, the pore is seen on the surface as a clear, circular opening continuous with the vacuole below, showing no intervening membrane. Longitudinal and cross sections through the axis of pore and vacuole also show that the pore and vacuole are continuous. The vacuole can be distinguished in all stages of systole and

1 These observations were largely on serial sections of Paramecia fixed with Gilson, Bouin, Meves, Benda, Flemming and Altmann among others, including solutions of iodides (e.g., Lugol's and 2 per cent. anhydrous iodic acid). The Altmann fixation gave by far the best results: absolutely no shrinkage; mitochondria, oil drops and cilia perfectly preserved. Of the various staining methods used, iron hematoxylin gave the best results. I am indebted to Dr. E. E. Just for turning over to me these slides, study of which served as a basis for these observations.

diastole so far observed. During the stage of maximum contraction it is a minute central space with delicate radiating tubes, each of which leads to the bulbous end of a feeding canal. As the canals give up their contents to the vacuole, the vacuole gradually increases in size; meanwhile, the bore of the canals diminishes. The distention of the vacuole in stages of diastole is at the expense of the proximal ends of the feeding canals. Thus, the walls of the canals are directly continuous with the wall of the vacuole. The pore, vacuole and canals make a permanent continuous structure.

The canals are slender tubes varying in extent and size according to their disposition and the stage of contraction of the vacuole. At the end of systole, when the vacuole may be said to be collapsed, each canal is markedly bulbous in that portion immediately distal to the radiation from the vacuole. In such a stage the canals may be likened to long-handled Indian clubs radially disposed with their bulbous ends in close proximity. As diastole progresses, the canals present more nearly parallel sides throughout their length. Toward the end of diastole and the beginning of systole, the canals show distentions farther away from the vacuole.

There is no evidence that the contractile vacuole is formed by accessory vacuoles, as described and figured by Khainsky ('10), nor does any section show a pulsatorial papilla or evagination, such as he

THE RESISTANCE OF THE TYPHOID
BACILLUS TO FREEZING

IN spite of the published work of Pearse, Sedgwick and Winslow, Park and North, most text-books on bacteriology state that Eb. typhi will resist freezing for a considerable time; and quote Taylor's investigation of the historic Plymouth epidemic in support of their views.

In a series of experiments conducted in this laboratory during the past year, Mr. W. A. Kreidler, a graduate student, obtained results which clearly indicate that this hypothesis is incorrect. Using artificial culture media, water, sterile and normal feces as the media in which the organisms were frozen, he was unable to obtain any growth of typhoid bacilli or the "Paras" after freezing for three weeks.

While we must realize that we can not exactly simuate natural conditions in the laboratory, it would eem that organisms which had been leading a saptogenic life for years would be more resistant to the conditions of the experiment than would the same organisms in a highly virulent parasitic condition.

The Plymouth typhoid epidemic was caused by a fresh and vigorous strain, as is indicated by the severity of the early cases. It is not likely, therefore, that it was caused by organisms which had been in a frozen medium for any length of time. I would suggest the theory that the epidemic was caused by the organisms in the feces which were deposited within a few days of the time the reservoir was opened, about the time of, or after, the thaw.

LABORATORY OF BACTERIOLOGY, LEHIGH UNIVERSITY

STANLEY THOMAS

ANALYZED SOUND

In the issue of SCIENCE for July 4, 1924, an interesting discussion of "Analyzed sound" by Alexander Forbes appeared. This description of the several instances coming to his attention brought to mind an experience of mine with a similar phenomenon oceurring at Oxford, Massachusetts, many years ago. Having very carefully kept journal records almost daily since 1898 of my thoughts, experiences, etc., in contact with all natural phenomena, I made a search of my journal and found the following record which I will copy just as written:

Aug. 11, 1902. Oxford, Mass.

As an early train passed by this morning, I noted a most remarkable echo every time it whistled. The first echo was immediate, sharp and distinct, appearing to rebound from a neighbor's buildings nearby. Some seconds after all was quiet, another faint, far-away

musical echo came stealing up the valley, apparently

emanating from a wooded hillside far away. The echo ever increased in intensity until it seemed to pervade every corner of the landscape, filling it with a wonderfal harmony of sound that beat upon the air in ever fainter waves, ever becoming farther away, until the sounds could no longer be heard. At no time were the sounds loud but seemed to fall upon the ear in infinite waves, as if thrown back from some invisible dome overhead. It did not seem to be a terrestrial echo, but seemed to fill the skies overhead with sweet, spiritual sounds, that seemed also to reecho far back in the skies, one could not tell where. I think some obscure atmospheric condition overhead was responsible for this remarkable echo, the most exquisite, the most sweetly celestial sound I have ever heard in the skies.

At the time I was greatly impressed with this remarkable sound phenomenon, but I have never since heard anything even approaching this strange break

IN connection with the article in SCIENCE of July 4, 1924 (page 5), on "Analyzed Sound," attention should be called to Lord Rayleigh's discussion of the phenomena half a century ago (Nature, 1873, Vol. VIII; "Theory of Sound," Chap. XV) under the title "Harmonic echoes." His conclusions from a mathematical investigation of the reflection of sound-waves from small surfaces, as tree trunks, were that the intensity of the reflected wave varied inversely as the fourth power of the wave length. The overtones in the echo of the voice would therefore be very much stronger relatively to the fundamental than in the original sounds and the effect might easily be called a change to the octave.

Many years ago there was such an echo at the Adirondack resort, Loon Lake, Franklin County, N. Y.

ANN ARBOR, MICH.

CHARLES K. WEAD

SCIENTIFIC BOOKS

Extinct Plants and Problems of Evolution. By D. H. SCOTT. Pp. xiv + 240. Macmillan & Co. London, 1924.

THIS little book, founded upon a course of lectures given at the University College of Wales in 1922, is a largely non-technical and very readable account of the main points in our knowledge of fossil plants, written for the non-specialist.

The first chapter is an all too brief, but very illuminating, sketch of the present status of the various

theories that have been advanced to explain the facts of evolution. A consideration of extinct floras is preceded by a very brief sketch of recent floras, and the former are taken up in the sequence from youngest to oldest. The great transformation periods of floral history are considered to have been the middle Devonian, the Permian and the mid-Cretaceous, ushering in respectively the so-called Carboniferous flora, the Mesozoic flora and the flowering plants. The consideration of the early Devonian flora is almost entirely devoted to considerations growing out of the recently discovered petrified material in the Rhynie chert, and showing certain bryophytic and algal char

acteristics. It seems to the reviewer that a somewhat misleading impression is given of the extent of the Permian transformation, which was really a gradual process when viewed in the true geological perspective. The consideration of the Mesozoic floras is

largely taken up with the Cycadophytes, and the author is seemingly greatly impressed with the analogies between the bisporangiate fructifications of the latter and those of certain angiosperms. The treatment of the flowering plants is very brief and, although avowedly incomplete, does not indicate any great knowledge of, or even interest in, the literature of the subject.

As is eminently proper in a book designed for a general audience, the author very fairly states all controverted questions and rightly refrains from arriving at decisions, which are indeed impossible in the present state of our knowledge. Without prejudice to his position he may, I think, be fairly said to favor the following propositions: That land plants probably arose from various specialized algal ancestors somewhat after the manner set forth in Church's speculations; that the vascular plants were consequently polyphyletic in origin and that the Rhyniaceae may have been reduction products of some algal stock; that the true ferns and the seed ferns were of independent origin; that there was a community of origin between the seed ferns and the Cordiatales, and that the conifers and the ginkgos took their origin from some cordiatalean-like ancestors; that there was a community of origin between the flowering plants and the Mesozoic cycadeoids, finally that on the whole the evidence is favorable to the truly Darwinian conception of an orderly and gradual evolution of the various plant phylae.

EDWARD W. BERRY

THE JOHNS HOPKINS UNIVERSITY

SPECIAL ARTICLES

A MECHANISM FOR THE COORDINATION AND REGULATION OF THE MOVEMENT OF CILIA OF EPITHELIA

THAT the movement of cilia in epithelia is coordinated is a fact of universal observation, but a structural mechanism in epithelia, by which this coordination of movement is conditioned and facilitated, has not hitherto been demonstrated.

Many biologists, especially physiologists, finding nothing in the structure of living epithelia suggestive of a coordinating mechanism and no reference in the literature of morphology concerning a durable, structural organization adequate to account for coordination of ciliary movement, have concluded that such a mechanism is not essential and does not exist. To account for the observed coordination of ciliary movement in epithelia, G. H. Parker,1 in 1919, definitely

1 G. H. Parker, "The elementary nervous system,' Lippincott Company, 1919.

formulated his theory of "neuroid transmission" a cording to which the coordinating impulses that pa from cilium to cilium are conducted, not by stru turally differentiated paths, but by virtue of "th elemental property of protoplasmic transmission fro which true nervous activity has been evolved." A cording to Parker ciliated epithelia present favo able conditions for the study of this elemental for of transmission.

The regulation and control of ciliary movemen such that it is correlated with the changing cond tions of the environment and physiological states the organism, is also a fact that is established by ob servation and experiment, although there are biol gists who assert that such regulation does not exist ciliated epithelia, according to their view, bein purely automatic in their movements and not adjust able to the changing states of the organism as whole. J. L. Kellogg2 holds to such a view, at leas so far as the ciliated tracts of the palps of lamelli branch mollusks are concerned.

During the past year we have made careful cyto logical studies of ciliated cells and epithelial of the gills of several species of fresh-water mussels of the genera, Lampsilis and Quadrula, and have been suc cessful in finding well-differentiated systems of fiber which fully satisfy all the requirements of coordinat ing and regulating mechanisms.

The differentiated mechanism we have been able to demonstrate in the latero-frontal ciliated epithelium of the gill of a species of Lampsilis is shown in Fig. 1 and is schematically represented in Fig. 2.

The cilia (C), in this type of epithelium, are paired, and members of pairs are fused at their tips (X). The number of pairs of cilia is approximately the same as the number of nuclei in the syncytial epithelium. A specialized cuticle is present at the external surface of the epithelium in which the cilia and their basal corpuscles (b) are implanted. In the proximal zone of cytoplasm, between the cuticle and the row of nuclei, a system of intra-cellular fibers or ciliary rootlets is chiefly distributed, although fibers belonging to the system may penetrate the cytoplasm between nuclei, and perhaps even to the basement membrane and the sub-epithelial layer of bipolar cells. This system of intra-cellular fibers may be analyzed as follows: each cilium splits, just below its basal corpuscle, into two fibers (m and n) which diverge at angles varying from 20 to 30 degrees, one to the right and one to the left in the plane of the row of cilia. The right hand branches (m and m'), originating from the members of a pair of cilia,

2 J. L. Kellogg, "Ciliary mechanisms of lamellibranchs, with descriptions of anatomy," Journ. Morph., Vol. 26,

1915.

section, appears to be formed between two fiber-like structures (r and 1) which join the cuticular border above, in two-minute granules, and meet at the lower border of the cuticle, midway between the bases of the cilia of two pairs, in a similar granule. This latter granule is the meeting place also for two comparatively short, robust fibers (R and L) which originate, one from the nearest basal corpuscle of the pair of cilia on the right of the space, the other from the nearest basal corpuscle of the pair on the left, and it is the point of origin for a longer, unpaired, vertical fiber (S), which penetrates the cyto

X

C

FIG. 1

gradually converge and join to form a single fiber (0), while the left hand branches (n and n'), join to form the fiber (o'). The fibers (o and o') join with corresponding fibers derived from adjacent pairs of cilia, to form the fibers (p and p') which may end on the nuclear membrane or penetrate the cytoplasm between nuclei. The part of this system, consisting of the fibers m, m', n, n', o and o', forms a mechanism which is continuous throughout the extent of the epithelium and is postulated as that which provides a basis for the coordination of ciliary movement. The continuations of this system, through the fibers (P, p', etc.) into the deeper parts of the epithelium, provide for the entry, into the system, of impulses, originating either in nuclei, the cytoplasm or bipolar cells of the subepithelium, by which movements of the cilia may be adaptively regulated in conformity with the state or needs of the organism as a whole. In addition to the mechanism for the coordination of ciliary movement, just considered, another series of structures is present in each of the segments of the cuticle bounded by pairs of cilia, which apparently serves another purpose. One of these systems may be described as follows: a minute space (0) interrupts the continuity of the cuticle midway between pairs of cilia in the plane of the series of cilia. This space opens on the surface of the epithelium and, in

It may be too early to indulge in sweeping generalizations, but we venture to predict that similar structural differentiations will be found in all ciliated epithelia. The facts of comparative morphology justify such a prediction. Function is so universally found to be associated with, and to depend upon, definite structural organization of living substance that in a tissue so specialized in function as that of a ciliated epithelium we may expect a priori to find in it a corresponding structural differentiation that is neither indefinite in form nor of temporary duration. The results of our investigation of various types of ciliated cells, which rest upon experimental as well as morphological evidence, will be fully reported and discussed in a paper to be published in the Journal of Morphology and Physiology.

WASHINGTON UNIVERSITY, ST. LOUIS, MISSOURI

CASWELL GRAVE, FRANCIS O. SCHMITT

PRELIMINARY NOTE CONCERNING PHYSIOLOGICAL SPECIALIZATION IN

FOMES PINICOLA FR.

THE idea of physiological specialization in the fungi has undergone extensive development during recent years. In fact, a considerable amount of literature on this subject has arisen since about 1890, and it has been demonstrated beyond all reasonable doubt that physiological specialization exists in a great number of fungi belonging to widely separated families. The rusts have received particular attention in regard to this point and many interesting as well as important facts have been brought to light by the work of Eriksson, Dietel, Stakman, Hungerford and others.

Other genera of fungi, as, for example, Erysiphe, Glomerella, Sphaeropsis, Rhyzoctonia, Septoria and many others, have also been investigated, but, as far as the writer is able to ascertain, little has been done along the line of physiological specialization in the case of the wood-destroying fungi. It is true that some work has been done on these forms, but the emphasis has been on the morphological rather than on the physiological aspects of the question.

In regard to their general life history, many of the wood-destroying fungi differ from most other fungi in that they may, as a result of a single infection, inhabit a single host plant for a great number of years. For example, it is not impossible, nor even improbable, that Echinodontium tinctorium, Fomes pinicola, Trametes pini, etc., may grow in a tree as a result of a single infection for twenty-five, fifty or even a greater number of years. If, then, the character and general properties of the host plant exert any influence on the fungi infecting it, tending to

produce physiological specialization, strains or varie ties, it would not seem unreasonable to suppose tha the chances for the production of such specialized forms or varieties among the wood-destroying Ba sidiomycetes would be very good.

There is also a very important practical aspect to this question. It is usually considered, in addition to other reasons, very poor practice from the standpoint of forest sanitation to allow infected trees to remain standing on an area upon which it is expected to raise future forest crops, even though these infected trees are of a different genus than those to be grown eventually. A concrete case will serve to elucidate this point. The white pine stands of the Inland Empire contain a considerable number of inferior species, such as white fir and hemlock. These latter species are often heavily infected with heartrot and many of such infected trees remain standing on the area after logging operations are completed. This is particularly true if broadcast burning does not follow the logging operations. These infected trees remain on the area at least during the early growth of the second crop. Very often the same species of fungi which cause the heartrot in these remaining trees also cause heartrots in the trees with which it is hoped to restock the area, as, for example, white pine. Thus Trametes pini causes more or less similar heartrots in fir, spruce, larch and pine. Fomes pinicola causes a red brown sapwood rot in spruce, larch, fir, pine and hemlock. Echinodontium tinctorium causes a heartrot in practically all the western true firs, Engelmann spruce, Douglas fir and western hemlock. Many other examples might be given, but the above are sufficient to illustrate the point. It is generally assumed, therefore, that these infected trees remaining on the area after logging constitute a menace to the future forest crop, even though it may be of a different genus. If, on the other hand, physiological specialization has developed to the extent that the strain common to white fir is limited to white fir, the Douglas fir strain to Douglas fir, etc., it is evident that the expense of falling and destroying these infected remaining trees might be eliminated when the forest sanitation is the only factor necessary to consider. The writer volunteers no expression of opinion on this point at this time, but merely calls attention to the situation.

It must be obvious that artificial infection experiments with the heartrot fungi are especially difficult and that it would take many years before any reliable data could be obtained. However, studies can be made on the physiological characteristics of these forms which may at least indicate the desirability of undertaking such artificial infection experiments, no matter how difficult or time-consuming the work may be.