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English words is found in the final e, which always denotes the long sound of the preceding vowel, as in tone, bite, hate, etc. It is true that recent writers on botany have frequently attempted to simplify the spelling of technical terms to the detriment of phonetic principles, and so we have such forms as mestom, plerom, hadrom, etc., which must be admitted to our dictionaries as variants of the infinitely preferable mestome, plerome, ha drome, still employed by careful writers. The fact that there are two Greek words khóv and kāóvos (the latter giving us the English adjective clonic) merely emphasizes the importance of properly indicating the longo in English derivatives of kūúv. I therefore suggest clone (plural clones) as the correct form of the word to be adopted in dictionaries, lexicons and general writings. It is to be hoped that the shackles of philology' to which Mr. Webber so feelingly refers will not prevent him from accepting this suggestion in the friendly spirit in which it is offered.
Charles Louis POLLARD. SPRINGFIELD, Mass.
the scale, a distance of an inch or more, to the micropyle, which they enter and after penetrating the long beak of the nucellus arrive at the archegonia. This method of pollination and growth of the pollen-tube is unique among the Gymnosperms so far as is known and its bearing on the problems of fertilization important-notably on what may for convenience be termed the “free-growth' theory of chalazogamy.
The double nature of the integument is very apparent in young ovules of Agathis, as Strasburger? long ago observed. The micropyle in some cases at least extends almost to the base of the nucellus on its upper surface, though usually not so far on the lower, in the form of V-shaped slits.
The archegonia are peculiar in structure arrangement and development. Their study is throwing new light on the character and relationship of these organs in the subgroups of the Conifers.
The vascular supply to the ovules worked out by series of celloidin sections is found to be different from the descriptions already given of it and promises very material aid in settling the vexed question of the primitive or specialized nature of the subgroup under consideration.
These features and other chiefly anatomical ones, added to the peculiarities presented by the megaspore-membrane and the tapetum, as described in the paper to which reference has been made above, place the Araucarineæ in a very isolated position among the subgroups of the Coniferæ. The forthcoming monograph, it is hoped, will make this clear and aid materially in the establishment of the phylogenetic position of the Araucarineæ.
ROBERT Boyd Thomson. BIOLOGICAL DEPARTMENT, UNIVERSITY OF TORONTO, June 20, 1905.
THE DEATH (?) OF AN AMEBA. While watching some amabæ on February 8 I observed one which was behaving in a singular manner. Instead of progressing in
? Strasburger, E., 'Die Angiospermen und die Gymnospermen,' p. 91, 1879.
In my paper on the megaspore-membrane of the Gymnosperms' a footnote refers to the occurrence of supernumerary nuclei in the pollen-tube of Agathis. Recently I have found that the number of nuclei in the pollen-tube of Araucaria may be even greater than that observed in the former genus, being over thirty in number in one instance at least. The supernumerary nuclei are placed fore and aft of the generative group in a parietal stratum of protoplasm not unlike that of the megaspore. Again the behavior of the pollen-tube in Araucaria is peculiar. The pollen-grains do not fall into the micropyle but are found at the distal end of the ligule more or less entangled in its serrated edge. From this point the tubes pass in grooves on the surface of the ligule or
1. The Megaspore- Membrane of the Gymnosperms,' by R. B. Thomson. University of Toronto Studies, Biological Series, No. 4, pp. 85-146, Pls. I.-V. 1905.
one direction this one appeared to be in a state of indecision. One end, which for convenience I shall call the anterior, was consistently trying to go in one direction. At the other end there was in progress an active formation of pseudopodia and an apparent endeavor to more in the opposite direction. The parenchyma of the amoeba contained a rather larger amount of granular material than usual, and this was a little more abundant towards the posterior end.
The formation of pseudopodia at the posterior end was first in one direction (Fig. 1), and then in another (Fig. 1, a). This was accompanied by simultaneous formation of pseudopodia at the anterior end. The intracellular struggle which then ensued, during which the granular protoplasm flowed from the central region into both posterior and anterior pseudopodia, would continue for a few seconds, to be followed by the retraction of the pseudopodia and a few seconds of quiet. At last (Fig. 3), after two or three such trials, there appeared to ensue a determined struggle between the opposing ends of the animal. Soon the central portion became narrow and thread-like (Fig. 4). This connecting bond at last broke, and it was then seen that the animal had divided into two approximately equal parts. The part which had been the posterior region contained more than half of the coarse granules. The new individuals moved away from each other in opposite directions, each following the direction of its previous efforts. The one that had been the anterior end of the undivided animal not only contained fewer granules than the other, but it also had a larger proportion of clear protoplasm at its anterior end. It behaved normally and quickly moved out of the field. The other (Fig. 6), after moving in a normal manner for a few seconds, ceased to form pseudopodia, and assumed an irregularly spherical shape (Fig. 7).
Up to this point I supposed I had been witnessing an ordinary case of division. Then occurred what looked like the dissolution of this bit of supposedly immortal living substance. The ectosarc and protoplasm dis
Sketches of a dividing ameba made from memory a few minutes after the events which they illustrate had been observed. 1, la, pseudopodia at opposite ends of the animal with energetic flow of the endosarc in opposite directions; 2, cessation of struggle, movement in only one direction; 3, renewal of struggle with elongation of animal; 4, beginning of division; 5 and 6, division completed, 5 normal, 6 abnormal new ameba; 7, position assumed by 6 a few seconds later; 8, spontaneous disruption of 7. No nucleus was seen.
took place. The dense protoplasm increased in bulk rapidly until the ectosarc, no longer able to resist the pressure from within, gave way suddenly.
There was sufficient vegetable debris present to keep the specimen from being crushed by the cover-glass.
No signs of life could be seen in the disintegrated part. It was simply a cluster of granules with no coherence and no connecting material.
The length of the undivided animal was about 0.03 millimeter. Several other ameebæ
of the same size and appearance were observed In marking animals and scars Higgins's in the culture, but none were seen behaving water-proof ink was used. White paint, which in an abnormal way. As I did not realize was used by Davis, was not accessible, but as that I had been witnessing anything unusual the ink marks last about three days they are until the final catastrophe, the time occupied fairly satisfactory. Siphonaria, being comby the division and the subsequent events up paratively small, was readily removed from its to the disruption of the short-lived half was scar; Fissurella I was seldom able to detach not noted. The whole operation lasted but a uninjured, and, accordingly, my observations short time, probably little longer than one upon this species were limited almost entirely minute.
Edwin LINTON. to watching its voluntary departures and re
turns. As might be anticipated, the animals, HOMING OF FISSURELLA AND SIPHONARIA.
unlike Patella, remain motionless on their The Patella is the only mollusc whose hom- scars during low tide, moving, if at all, only ing powers have been investigated. Fissurella, when the incoming water has moistened and a rhipidoglossate prosobranch, and Siphonaria, cooled their immediate surroundings. which stands on the border line between the Siphonarias did not home when removed to opisthobranchs and the pulmonates, while dif
a distance of more than six inches and were
a distance fering more or less widely from Patella in
most likely to return when removed not more structure, closely resembles it in the form of
than two inches. A quiet and shallow tidethe shell and in their littoral habits. It was,
pool furnished the most favorable conditions therefore, an interesting question whether
for their return.
If the animal, on being they resemble it also in the possession of the
transferred, was set down with its head away homing power. A stay at the Bermuda bio
from the scar, it turned in the proper direclogical station in the summer of 1903 gave
tion and, so far as I could judge, those headed an opportunity to answer this question, al
away were quite as likely to get back as those though a few days only being available for
headed toward the scars. In general, animals the investigation, it was by no means as complete as could be wished. Such as it is, how
which lost their way seemed to crawl restlessly ever, I present it for the benefit of future
about for two or three days; each time one students of the subject.
was visited it was found in a new place. One, The specimens studied were Siphonaria
however, settled down at once in a new home alternata Say and Fissurella barbadensis
and at the end of the third day had made a Gmelin. Both are abundant at Bermuda,
discolored spot. On being transferred to his where they live clinging to the exposed faces old home he apparently failed to recognize it of the bare rocks between tide marks. Bare and immediately crawled away. Usually the rocks. I say, for to a New England eve one scar was recognized at once by a returning of the most striking features of the Bermuda
wanderer, and on reaching its edge he would coast is the entire absence of the larger algæ, turn about, if necessary, so that his shell might which upon our own rocky shores shelter so
fit the scar, would slip on to it and settle large and varied a fauna. The rocks are down. Siphonaria alternata thus appears to calcareous, soft and of irregular surface and have a sense of direction, the ability to recogthe home of Siphonaria is recognizable by a nize its own recently-left scar, and the power greenish spot where the foot has rested. That of homing when removed not more than six of Fissurella, as my notes show, is also clearly inches. marked. though I have carelessly omitted to Experiments with Fissurella, as I have said, note how it may be known. Both species, as were usually unsuccessful. That these molwill be seen from the following notes, exhibit luscs have the power of homing is seen, howundoubted though limited homing powers.
ever, by watching them. As soon as the tide 1 These specimens were kindly identified for me has so covered him that he is not exposed to by Mr. Charles W. Johnson of Boston.
the wash of the waves a Fissurella is very
Ideally, the author should himself be able to make the original drawing quickly, neatly and artistically. The usual execution of drawing with the pen is, to the average author, discouragingly slow and expensive, not always neat, and still less often artistic. The following note relates to some experiments made to increase rapidity and neatness in the production of line drawings by the use of a machine. At the outset the experiments were,
likely to start on a brief journey, going only about two inches from the edge of his scar, and returning to settle upon it again, sometimes within fifteen minutes from the time of his leaving it. In no experiment did I find a Fissurella homing if he had been remored more than three inches, though one which had been removed six and a half inches was nearly half way back in twenty-four hours. My departure from Bermuda prevented my learning his final fate. Fissurella, like Siphonaria, recognizes his scar and orients himself properly with reference to it as soon as he reaches it. In one instance I found a scar occupied by two animals; one was the owner, who had evidently returned from his wanderings to find that a usurper had already taken possession of half of his home. He had, however, crawled on to as much of the scar as was still unoccupied and the next day was in sole possession, while the intruder had disappeared. Fissurella barbadensis, then, undertakes short voluntary excursions and returns to his scar, but his power of homing when removed by some one else has not been fully tested. M. A. Willcox.
MACHINE-MADE LINE DRAWINGS FOR THE ILLUS
TRATION OF SCIENTIFIC PAPERS. It is safe to say that the majority of persons who from time to time publish scientific papers are seriously hampered in the preparation of text illustrations by the difficulty and expense entailed in the tedious drawing of map, section or diagram. Comparatively few authors can command the services of skilled draughtsmen or have themselves the requisite training to produce satisfactory line drawings. Yet the desirability of greatly increasing the proportion of such illustration in the thousands of scientific articles published each year is manifest. That clearness, precision and conciseness in the exposition of a theme are generally enhanced by the use of abundant, appropriate diagrams is as evident as that the blackboard is the constant friend of the teacher of any branch of natural history or philosophy; the printed page needs its blackboard.
for obvious reasons, planned without any idea of rivaling the artistic work of the pen in a skilled hand. The aim has been to secure economy of time in execution and clear-cut precision of legend for the drawing. In both these respects enough success has been attained to warrant the recommendation of the machine method to geologists, geographers and others who desire to prepare useful text
fitted with a black record silk ribbon. Recently the Hammond Typewriter Company of New York has constructed, from the writer's specifications, a typewriter provided with a carbon ribbon and with ninety special characters designed for the preparation of line drawings to accompany geological and geographical papers. The same machine can be similarly used for statistical, engineering and other diagrams of a more or less mechanical and simple composition. Of course, this method should not wholly replace the use of the pen even, for example, in the differentiation of areas in a geological map or section. The ultra mechanical look of the typewritten legend can often be pleasingly relieved by the
The typewriter has its most general application in lettering, that most difficult element in line drawings. The particular machine made by the Hammond Company has the advantage of making it possible to employ a great range of type styles. Using the carbon ribbon, the writer has found that any one of the one hundred and twenty-five shuttles made for the machine (each shuttle bearing ninety characters and including the lettering for one of twenty-six different languages), will give an impression suitable for photographic reproduction. Each shuttle can be placed in the machine ready for work in a few seconds. The shuttles now on the market cost $2.50 each and any new character can be supplied