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are present in a pabulum, though in small quantity only, the mildew usually commences to be visible to the naked eye as minute yellow spots. These, as we have just said, may be caused by the growth of the mycelium, which in providing nourishment for itself and for the subsequent fructification of the fungus, brings about a decomposition of the nitrogenous materials, and gives rise to crenic and other organic acids. At a more advanced stage, humic and ulmic acids are produced, the fiber of the cloth becoming at the same time perceptibly more tender. It has been said that mildew may exist on the sizing only of a fabric. We are inclined to doubt this, for in our experience the mycelial threads have never been confined to the surface size alone, but could always be traced ramifying amongst the cotton filaments. If the size alone of a cloth were smitten with mildew, the cloth itself would not be tendered, unless the acids we have mentioned were a sufficient cause, which is not so. We believe it impossible for mildew to be present in such amount as to be clearly visible to the eye without a penetration of the mycelium to the textile substratum, and should expect a suitable magnification and illumination of the object to reveal the fact.”

As to the colors of mildews, according to the authors, yellow patches on cloth are mostly due to the presence of crenic acid, although very rarely they proceed directly from the fungus, Penicillium sitophilum ; green mildew is nearly always due to the fructification of Penicillium crustaceum, and dark-green or greenish-gray mildew is owing to the fructification of a Penicillium or Aspergillus, or to the mycelium of a species of the Dematiei. Brown mildew may be due to the presence of apocrenic acid, or of one or more of many fungi. Red patches appear to be due to fungi; those mentioned by the authors being a species of Epicoccum, Aspergillus roseus, and Papulaspora sepedonioides.

ALLEN'S CHARACEÆ AMERICANÆ EXSICCATÆ. We have had the pleasure of examining Part 1 of this important distribution of curious and little known plants. It includes three species of · Nitella, and seven species and varieties of Chara. The specimens are of generous size, and are in excellent condition for study. The more interesting species are Nitella intermedia, a new one, described by Nordstedt; N. megacarpa, a new species now first described as such by Allen ; Chara sejuncta A. Br., C. gymnopus A. Br., var. Michauxii A. Br., a gigantic species, and C.hydropitys A. Br., var. septentrionalis. The variety last named is described by Nordstedt, and is the same plant which Dr. Halsted described as a new species under the name of C. Robbinsië in the Proceedings of the Boston Society of Natural History, xx, 1879. Nitella megacarpa Allen, is the same as N. intricata Ag., in Halsted's paper; it is of very large size, and compared with the diminutive N. tenuissima is a giant indeed.

The publication of sets of specimens like these cannot fail to stimulate a search for these interesting plants by American botanists, and it is to be hoped that during the coming season all collectors who can do so will render what service they can by gathering abundant specimens and forwarding them to Dr. Allen, at 10 East 36th street, New York. There are few localities in which half a dozen or more species cannot be found. We are informed that the author has already material for forty or fifty species or clearly marked varieties, and is confident that the number will eventually reach seventy-five.-C. E. B.

THE PEPPERIDGE TREE IN MAINE.–Our attention has been called by Professor G. H. Stone of Kent's Hill, Maine, to the fact that the pepperidge or tupelo (Nyssa multiflora) is a native of Maine, although neither Gray nor Wood so state in their manuals. It is given as one of the trees of the State in the " Portland Catalogue of Maine Plants, 1867," and according to Dr. Goodale, was found at Winthrop and Waterville, by the late Dr. Holmes. Professor Stone sends specimens from Kent's Hill, Kennebec county. The importance of this note lies in the fact that Vasey, in his "Catalogue of the Forest Trees of the United States," gives its range as "from Massachusetts to Illinois, and Southward,” while Sargent, in his preliminary “Catalogue of the Forest Trees of North America,” gives it as from " West Milton, Vermont, South to Florida ; West to Michigan, Missouri and Arkansas.”—C. E. B.

HISTOLOGY OF THE PUMPKIN STEM.—Professor J. C. Arthur has
been studying the stem of the pumpkin, and in an article in the
Botanical Gazette sums up the tissues as follows :
Epidermal System :

Fibro-vascular System :
Epidermis.

(Cambium.)
Stomata.

Phloem,
Hairs.

Sieve-tubes.
Fundamental System :

Phloem parenchyma.
Interfascicular parenchyma.

Xylem.
Hypodemia.

Vessels.
Cortical wood.

Annular.
Cortical parenchyma.

Spiral.
Collenchyma.

Reticulated.
Scalariform.

Pitted.

Wood parenchyma. Professor Arthur directs attention to the value of the pumpkinstem for use in the instruction of classes in the Botanical Laboratory, furnishing, as it does, so many examples of the tissues of the higher plants. We can also testify to its value, having used it for many years for the purpose recommended.

We always secure every autumn several feet of stems, which we cut up and preserve in jars of alcohol, for future use in the laboratory.

FERTILIZATION OF AQUILEGIA.—The species of Aquilegia to which I referred, and on which Mr. Trelease comments, have nectaries of 40 millimetres long; while 21 is the longest beestongue as he believes. But the species I noted have curved nectaries, which it would probably try the patience of a busy bee to course, even if the tongue were long enough. Moreover if my observations are worth any thing, Aquilegias hereabouts are cross-fertilized by pollen-hunting insects. It may be that honey bearers cross-fertilize them sometimes, for one man cannot see everything; but I have never seen a case.

If this be the fact, as I believe it to be, the arrangement of the nectarium in the case is superfluous.- Thomas Meehan.

The Editor of this department has in preparation for the NATURALIST a sketch of the Progress of Botany in the United States in the year 1880, and solicits copies of papers and other publications made during the year, together with such other information as will make the account as full and accurate as possible.

BOTANICAL NOTES.-A good many years ago DeBary suggested the animal nature of the slime moulds (Myxomycetes), and was very severely criticised for doing so, the naturalists of that day feeling bound to maintain the old dogma of the absolute distinctness of the animal and vegetable kingdoms. Now, however, any one at all familiar with the Monera and the slime moulds cannot fail to see the remarkable similarity between the organisms which, on the one hand, are called animals, and on the other, plants. This has led W. Saville Kent, in his recently published work on “Infusoria,” to take strong ground in favor of regarding them as animals. M. C. Cooke, in Grevillea for December, rather impatiently takes the learned author to task for his boldness. After all, what is the use of quarreling over a matter like this ? The position of the slime moulds in the great kingdom of life, is the same whether we draw our imaginary bisecting line on this or that side of them.

— The temper of the discussion of the foregoing question is much like that which (on one side at least), characterizes the articles on the several theories as to the nature of Lichens. A good illustration of this occurs in the same number of Grevillea, in a letter from Dr. Minks, the propounder of the new doctrine of the intra-hyphal origin of the gonidia of lichens. Dr. Minks attempts to set right Mr. Phillips' somewhat defective translation of the former's paper on Microgonidia in Revue Mycologique, and, it must be confessed, scarcely betters the

At some future time a summary of Dr. Minks' doctrine will be given in these pages.- Charles B. Plowright, in Grevillea, describes the method of spore diffusion in a species of morel

Morchella gigas). Specimens gathered and laid upon boards in a room, were observed in the slanting rays of the setting sun to be surrounded by a cloud three or four inches deep on all sides.

Proved to be due to the myriads of ascospores which were elastically escaping from the asci. In the December Jour

matter.

This

Murray's experiments undertaken to determine the method of the diffusion of the conidia of the potato disease ( Peronospora infestans). Microscopic slides coated with glycerine were exposed on the lee side of an infested potato field, and carefully examined at intervals of from ten to twelve hours, i. c., at 9 A. M. and 7 P. M. No conidia were caught during the night, but upon the twentyeight square inches of surface exposed during the day, there were caught in the first day 15 conidia; in the second, 17 ; in the third, 27; in the fourth, 4; in the fifth, 9. Considering the small amount of surface exposed by the slides, and the fact that only about two per cent. of the potato plants in the field were diseased, the number of conidia caught is very large.- Henry M. Douglas, of South Richland, N. Y., has undertaken to translate the successive numbers of the Botanische Zeitung, as they appear.

Queen & Co., of Philadelphia, have prepared a series of twenty-four slides of microscopical specimens illustrating many points in the histology of the higher plants. They are neatly mounted and will be useful to many teachers and students. The American Monthly Microscopical Fournal has, during the past year, contained many valuable botanical articles; among these may be mentioned several Notes on Fresh-water Algæ, Double-staining of Vegetable Tissues, The Salmon Disease and its Cause, besides many upon Diatoms. The microscope is now indispensable to the botanist, and it is encouraging to find that microscopical journals are beginning to make themselves useful to him also.— Science has now a botanical department.- W.P. Schimper's herbarium (of mosses) has been purchased by the Kew Herbarium. - In Nos. 46–50. of Botanische Zeitung, Goebel publishes an interesting paper on the Morphology and Physiology of Leaves, accompanied by a plate with many figures.- In No. 50 of the same journal Strasburger's paper on cells with several nuclei, and some points in the embryogeny of Lupinus, promises to be of considerable value.

A new and thoroughly revised edition of Rabenhorst's Cryptogamic Flora of Germany, Austria and Switzerland is announced. Of the first volume (Fungi), the first part is now ready.

ZOOLOGY. DESCRIPTION OF A HERMAPHRODITIC PHYLLOPOD CRUSTACEAN (EUBRANCHIPUS).—The single specimen of Eubranchipus vernalis here described was found in January, 1880, in a small, isolated pool, near Maspeth, L. I., living in company with a great number of a pale, transparent race of Eubranchipus vernalis Verrill. The hermaphrodite belonged to forni A, as already pointed out in a paper read before the American Association for the Advancement of Science, in August, 1880.

Owing to my often taking it out for closer inspection, it died after having been kept in the aquariam for three days.

Genital Organs.—The female side consisted exteriorly of two closed protuberances, a larger, less pointed one, opposite the cirrus, corresponding with the valvule, and a smaller one a little above the middle of the sac where the muscle ma is inserted. The internal female organs were but poorly represented, consisting of a somewhat triangular “oviduct," with its two elongate termini closed and suspended by three principal muscles. The latter

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ovrum FIG. I.—Hermaphroditic form of Eubranchipus vernalis V. The first three postabdominal segments. h, heart; hh, ostium of heart; i, intestine; t1, testicle ; ti, Ist dilated part of test. ; , contr. part or vas. def.; t", ad dilat. part or sem. ves. ; dt, duct ejac. ; g, glandular and access. app.; C, cirrus ; III, 3d post-abd. segt. ; iv, 4th post-abd. segt. ; ov, ovarial twisted string; od, oviduct, ovum-egg; c.g., cement. glands; m' m2 m3, muscles of the oviduct. anastomosed with the generally intricate mass of muscles. (The latter is omitted in Fig. 1.) Muscle m?, of Fig. I, was inserted near the larger, outer protuberance broadly spreading over the anterior terminus of the oviduct, the muscle (m) below the posterior terminus of the oviduct, and muscle (m2) was inserted in the second smaller, outer protuberance.

This outer protuberance was constantly contracting and expanding itself, the area of the motion was exteriorly confined to this small protuberance only. The rhythmic contraction of the three principal fascicles revolved the "oviduct" to about one-fifth of its shorter diameter, in a semi-lateral direction.

There was no dissepiment between the male and female sac, and the interior uterine second sac was entirely absent in the female half.

The ovarial string passed up from the post-abdomen behind the

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