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PROCEEDINGS OF SCIENTIFIC SOCIETIES.

Nova Scotian Institute of Science..-March 9th.-The following paper was read: "Some Illustrations of Dynamical Geology in Southwestern Nova Scotia," by L. W. Bailey, Esq., M. A., Ph. D. HARRY PIERS, Secretary.

Boston Society of Natural History.-February 19th-The following papers were read: Mr. Outram Bangs: "The Terrapin an Inhabitant of Massachusetts." Dr. Joseph Lincoln Goodale: "The Vocal Sounds of Animals and the Mechanism of their Production."

March 4th.-The following paper was read: Prof. F. W. Putnam: "Symbolism in Ancient America.".-SAMUEL HENSHAW, Secretary.

New York Academy of Sciences-Biological Section.February 7th, 1896.-Dr. J. G. Curtis in the Chair.

A communication from the Council was received asking that the Section take action on Rep. Hurley's bill "To fix the standard of Weights and Measures by the adoption of the metric system of weights and measures."

On motion of Dr. Dean, the Section approved the bill and the Secretary was directed to express the entire commendation of it to the Council.

Dr. Arnold Graf read a paper on "The Structure of the Nephridia in Clepsine." He finds, in the cells of the intra-cellular duct, fine cytoplasmic anastamosing threads which form a contractile mechanism. These are stimulated by granules which are most numerous near the lumen of the cell, and thus a peristalsis is set up which moves the urine out of the duct. In the upper part of the intra-cellular duct, the two or three cells next to the vesicle or funnel have no distinct lumen, but are vacuolated; the vacuoles of the first cell being small, those of the second larger, and so on, till the vacuoles become permanent as a lumen. He explains the action of the first cell as being similar to the ingestion of particles by the infusorians. The matter taken up thus from the funnel by the first cell is carried by the rest, and so on till the cells having a lumen are reached. The presence of the excretum causes the granules to stimulate the muscular fibres of the cells; penstalis results and the substance is carried outwards. The character of this contractile reticulum offers an explanation of the structure of a cilium as being the continuation of a contractile reticular thread.

N. R. Harrington, in "Observations on the Lime Gland of the Earthworm," described the minute structure of these glands in L. terrestris, and showed that the lime is taken up from the blood by wandering connective tissue cells which form club-shaped projections on the lamellae of the gland, and which pass off when filled with lime. The new cell comes up from the base of the older cell and repeats the process. This explanation is in harmony with the fact that in all other invertebrates lime is laid down by connective tissue cells. Histological structure and the developmental history confirm it.

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Dr. Bashford Dean offered some observations of the Lower Vertebrates." The young of Amia calva, the dogfish of the Western States, attach themselves, when newly hatched, to the water plants at the bottom of the nest which the male Amia has built. They remain thus attached until the yolk sac is absorbed. As soon as they are fitted to get food they flock together in a dense cluster, following the male. When hatched in an aquarium they go through the same processes. The young fry take food particles only when the particles are in motion, never when they are still. The larvæ of Necturus also take food particles that are in motion.-C. L. BRISTOL, Secretary.

American Philosophical Society.-January 17th.-Prof. Hilprecht presented a paper on "Old Babylonian Inscriptions, Chiefly from Nippur," Pt. ii.

February 21st.-Prof, A. W. Goodspeed read a paper on the Röntgen method, with demonstration. Remarks were made by Prof. Houston, J. F. Sachse, Prof. Robb of Trinity College, and Prof. Trowbridge of Cambridge.

March 6th. The following paper was presented: "Eucalypti in Algeria and Tunisia from an Hygienic and Climatological Point of View," by Dr. Edward Pepper.

Academy of Natural Sciences of Philadelphia-Anthropological Section.-February 14th.—The following papers were read: Dr. Allen on "Prenasal Fossæ of the Skull;" Dr. Brinton on "Human Hybridism;" Dr. McClellan, Skulls and Photographs exhibited. CHAS. MORRIS, Recorder.

The Academy of Science of St. Louis.-February 17, 1896. -Dr. Adolf Alt spoke of the anatomy of the eye, and, by aid of the projecting microscope exhibited a series of axial sections representing the general structure of the eye in thirty-one species of animals, comprising two crustaceans, the squid, three fish, two batrachians, two reptiles, ten birds, and eleven mammals.

Professor F. E. Nipher gave an account of the Geissler and Crookes tubes and the radiant phenomena exhibited by each when used in connection with a high-tension electrical current of rapid alternation, and detailed the recent discoveries of Professor Röntgen, showing that certain of the rays so generated are capable of affecting the sensitized photographic plate through objects opaque to luminous rays. Attention was also called to the experiments of Herz and Lodge with discharges of very high tension alternating currents, which showed that by the latter certain invisible rays are produced, which, like the Röntgen rays, are capable of passing through opaque bodies, such as pitch, but differing in their refrangibility by such media.

March 2d. Mr. F. W. Duenckel presented a comparison of the records of the United States Meteorological Observatory, located on the Government building in the city, with the record for the Forest Park station, showing that the daily minimum averaged decidedly lower at the Forest Park station than in the city, while the wind averaged decidedly higher for the city station.

Professor E. E. Engler spoke on the summation of certain series of numbers.-WILLIAM TRELEASE, Recording Secretary.

SCIENTIFIC NEWS.

The Journal of Comparative Neurology, which is now entering upon its sixth volume, has its editorial facilities considerably enlarged by the addition to the staff of Dr. Oliver S. Strong, of Columbia College. Professor C. L. Herrick continues as Editor in-Chief. The Managing Editor for 1896, is C. Judson Herrick, to whom business communications should be addressed at Denison University, Granville, O. Editorial communications may be sent to either of the three editors.

THE

AMERICAN NATURALIST

VOL. XXX.

May, 1896.

353

THE PROBABLE INFLUENCE OF DISTURBED NUTRITION ON THE EVOLUTION OF THE VEGETATIVE PHASE OF THE SPOROPHYTE.

BY GEO. F. ATKINSON.1

In this paper the discussion of the influence of nutrition, applies chiefly to that source of nutrition in plant organs provided with chlorophyll, and presupposes, in general, that the ordinary physiological processes, other than the one which is termed carbon assimilation, are normal. In all such plants some development of this vegetative part of the plant must take place before spore production, or fruiting, of a kind which represents a real increase at the time, can be accomplished. Some apparent, but not real, exceptions to this might be noted. In germination of the spores of Oedogonium, frequently spore production takes place without the development of any such vegetative part of the plant, but there is no real increase of the plant substance. This kind of spore production is only a means, perhaps, to tide over some condition unfavorable for the elaboration of the vegetative phase of the plant, which is present at the time and place. In Coleochate, germination of the oospore results in the formation of a cellular mass, which 1 Cornell University.

is larger than the oospore, breaks the enclosing wall, and the cells escape as a number of zoospores in place of one. But in this oospore are the stored products of carbon assimilation of the parent chlorophyll phase of the plant, and this case only differs from that of the Bryophyta, in that the sporophyte becomes separated, with stored products, from the gametophyte, before the differentiation of the spores.

In the higher plants many cases of bulbs, corms, tubers, etc., might be cited to show that the development of the sporophylls, and even fruit, might take place without the accompaniment of chylorophyll bearing organs. But here also the bulbs, corms, etc., represent, in the stored products of carbon assimilation, the preceeding green leaves. In certain ferns, as Osmunda cinnamomea, the sporophyll, which is completely differentiated from the vegetative leaf, appears first in the spring, and could mature its spores without the aid of the vegetative leaves of that season, but the green leaves of the previous season formed the necessary carbohydrates, which are stored in the rhizome and rudimentary leaves during the winter and in fact the sporophylls and sporangia are partly developed at the close of the previous season.

We might say, then, that in general, all spore production in plants, which themselves assimilate carbon dioxide, is necessarily preceeded by a greater or lesser development of chlorophyll bearing organs. This may appear to be a too well known axiom for even the brief discussion here given, but it is necessary in view of what is to come to have this axiom well in mind. Chlorophyll bearing organs, or tissues, then, as compared with sporogenous organs or tissues, are, in point of time within the life cyle, primary, while the latter are secondary. This proposition should not be regarded as opposed to the primary evolution of the sporophylls as compared with the foliar organs of the sporophyte. It applies only to a comparatively limited extent of time; to the usual cycle between the vegetative and fruiting phases; to the ontogenetic, not to the phylogenetic, development. It applies with equal force to plants in which either the gametophyte or the sporophyte forms the chlorophyll bearing organ.

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