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cating epochs in the growth of the shell. Marginal setæ of the mantle well developed, those on either side at the extremity longer than the rest, equalling in length one-third the width of the shell. There are two black spots on the margin of the mantle at the extremity. Peduncle in life three times as long as the shell, thick, (one-third width of the shell,) at its point of attachment, but rapidly tapering and becoming very slender and hyaline, with an opaque axis or central cord; extremity glutinous and covered with adhering sand. Length of the animal 3-5; length of shell, 0.92; width of shell at the middle 0:35; at extremity, 0-21; half way between middle and summit, 0.26 inch.

This animal was found imbedded in the weedy sand at low water mark, on the occasion of one of the extraordinarily low tides which occur at the equinox. It lives in a perpendicular position with its peduncle deeply penetrating the sand, and its shell scarcely projecting above the surface at its extremity. When drawn out and placed in a vessel of seawater it showed its uneasiness by snake-like gyrations of the peduncle, which, far from being a simple stem for attachment, is a powerful muscular organ, filling the function of the foot of the Lamellibranchiata. Mr. Peale informs me that this part in the Lingula anatina forms a favorite article of food among the Fiji Islanders. Our Lingula appears to be not uncommon near Beaufort, as several specimens were found during a single retreat of the tide. It is interesting as being the first species* of this most ancient genus described from the Atlantic ocean. The other recent species, ten in number, are all inhabitants of the Pacific.

EUCERAMUS, nov. gen. fam. Porcellanidae. Body subcylindrical. Carapax elongate-subrectangular, twice as long as broad; sides parallel. Front prominent, tridentate. Eyes minute, longitudinal, projecting a little beyond the orbits which are very incomplete, consisting only of the concave superior margin. Antennule placed immediately beneath the eyes; peduncle anteriorly bidentate. Antennæ large; mobile part nearly as long as the carapax and arising from the inner or superior side of the small coxal joint, thus being in contact with the eye at base. The outer maxillipeds are of the form usual in Porcellana, but the sternal piece to which they are attached is very large, nearly as long as broad, triangular in front, and truncate behind. Chelipeds small, subcylindrical, much shorter than the carapax; hands weak. Ambulatory feet subcylindrical; dactyli curved, setose, nearly as long as penult joint. Abdomen narrow, particularly in the males; appendages as in Porcellana.

This aberrant type should be referred to the Porcellanidea, notwithstanding its greatly elongated form, which would lead one to refer it at first sight to the Hippida or Raninidea.

EUCERAMUS PRÆLONGUS. Carapax regularly curved like a segment of a cylinder, above glabrous, and minutely striated transversely; striæ curved forward at the sides. Inter-orbital front one-third the width of the carapax, tridendate, teeth slender, pointed, median longest. Hands externally scabrous, or small-tuberculose and setose; fingers as long as the palm and not gaping. Ambulatory feet of the second and third pairs as long as the chelipeds; those of the first pair smaller. Length about three-fourths of an inch. Dredged on shelly ground in 4 to 8 fathoms.

*We understand that there is a specimen of Lingula from the coast of South Carolina in possession of Prof. Agassiz. Not having access to this specimen, we are unable to say whether it be identical with ours or not.

long. 121° 29' 44"; by THOMAS M. LOGAN, M.D.

IV. METEOROLOGY AND ASTRONOMY.

-with the average of seven years—at Sacramento, Cal., lat. 38° 34′ 41′′, 1. Abstract of Meteorological Observations, made during the year 1859

1859.

January, Feb'y. March.

April.

May.

June.

July. August. Sept.

Oct.

Nov.

Dec.

Mean.

7 years average.

Barometer.

In.

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5.5 3.7 2.9 2.2 0.5 0.7
0.964 3.906 1.637 0.981 1037 0.000 0.030
111 2-3 4 18832 5256 29 3 10 1 106 13 06 732-2 103 14 7 14 14
6201 171 12 2201111 1104' 0 0-0 030 00 2 12 13 12 5
113101 08 1 20 17 103 107 000 1305 2 142 17 2
62.88 315 32 3 194 18 2 11 42.2 52-340-8 3 16 8 27 7
26101 29 9 26 11 22 18 25 15 25 7125 51204 30 1 2095326
32 8 30 323 6317 4 23 412-2521 2102 17 0 0041 19
21 8 272 15 21 13 3 26 316 3 15 1 03110
36 113032·6 2 0·7 107 1 07 118 84333 21 1 23221-

0.4

1.4

1.3

5.7

4.1

2.9

3.3

0.000 0.025 0000 6485 1834 16 899

16-927

14 8131-7
1721 11
1813 11

2163 21

0726 14

General Remark.-The climatic feature of predominant interest in California lies in the rains of winter, which, although they fell in the early part of the present season in ample abundance for agricultural purposes, nevertheless, in their subsequent diminution, confirm the opinion expressed by us in former remarks, that the cultivator of the earth cannot depend with any certainty upon them alone, but must be prepared to supply their deficiency, whenever it occurs, by irrigation-for which expedient no other country, perhaps, is better adapted, both as regards soil and climate, as well as facilities of commanding water.

2. Daylight Meteor of Nov. 15th, 1859. Of this remarkable body Professor Loomis has already published an interesting account at p. 137 and 298 of this volume. The meteor being one of the most brilliant on record deserves the fullest possible investigation, and we are glad to find in the Journal of the Franklin Institute of Philadelphia, for March and April, a valuable paper thereon by Mr. Benj. V. Marsh of that city, giving an extensive series of observations which he has collected, together with his deductions therefrom.

The meteor was seen in full sunshine, as a large ball of fire, from Salem, Mass., to Petersburg, Va. Its path was probably inclined to the vertical about 35°, and the direction of its motion was nearly west. Its velocity was very great, perhaps full 30 miles per second, and the meteor appears to have become luminous when more than 100 miles above the earth. During its brief passage of two or three seconds, it exploded several times, with reports which were loud and violent. These reports or detonations made two series, the whole occupying only half a second of time, the individual sounds being distinguishable because of the different distances they had to travel to reach the ear. The column of smoke resulting from the explosions was nearly a thousand feet in diameter, and its base was vertical about four miles north of Dennisville, N. J. The immense volume of smoke or substance of the meteor, dissipated by its excessive heat, shows that the body was of very considerable magni tude. The meteor's path would strike the earth near Hughesville, on the northwestern boundary of Cape May County, N. J., in which vicinity, or a few miles further west, it is probable that fragments may yet be found. Will nobody look for them?

V. MISCELLANEOUS SCIENTIFIC INTELLIGENCE.

1. Probable Origin of Flint Nodules in Chalk.-DR. G. C. WALLICH, Surgeon in the Indian army, has published (in the Quart. Jour. Microscopical Sci., No. xxx, p. 36) an interesting paper on the siliceous organisms found in the digestive cavities of Salpæ-embracing under this head the whole molluscoid tribes that frequent the open sea in shoals and live upon the microscopic organisms it contains. These creatures are in their turn the food of whales. In the digestive cavities of the Salpa the siliceous shields of Diatomaceæ, &c., are freed of all or nearly all their soft portions, and these minute organisms aggregate into masses which in the whales are further aggregated and in the form of coprolites fall in vast numbers upon the pulpy cretaceous strata of Foraminiferæ, &c., now known to form the bottom of the ocean in many places, imbedding themselves there as nodules similar to, certainly, if not identical with, the flint nodules in the Chalk.

2. New form of Compressor for use with the Microscope, (in a letter to Prof. G. C. SCHEFFER).-My Dear Sir,-At your request I enclose a sketch of the little instrument that I use as a substitute for the ordinary compressor, in mounting objects for the microscope.

The frame a, is made from one

piece of hard brass, possess

ing

sufficient

elasticity for the

purpose,-held in place and adjusted by the milled nut on the screw b.

This screw is firmly riveted

in the frame at a, and plays freely in a slot at b. The swinging tripod, (also cut from one piece,) is loosely riveted to the bent end of the frame as shown in section at f, having sufficient play in the collar to adjust itself to any inequality in the slide or the cover.

The centre of the frame, at c, under the tripod, is pierced with a hole of sufficient size to see the object to be mounted, so that the pressure from the screw can be adjusted without injury to the object. The sketch shows a slide, d, and cover, e, in place.

For mounting objects dry, or for covering cells I find it useful as it enables me to hold the cover securely while I have access to its entire edge, and can turn it in every direction to apply the cement. For mounting objects in balsam which require very thin covers, say 01 to 005 of an inch, such as the silicious epidermis of plants and other test objects, I add to the pierced hole in the frame a circular shield of glass, a little less in diameter than the cover, and of the thickness of an ordinary slide, imbedding but a small portion of its thickness in the brass. Then, after placing the cover on the balsam, and spreading it by heat, I put the slide cover down in the frame, and apply a pressure to drive off the superfluous balsam. The raised surface of the glass shield, keeps the exuding balsam from the frame, and at the same time prevents any bulging of the thin glass at the centre. Dried in this way, under pressure, it is easily taken from the frame and cleaned. I have found it a very simple and satisfactory way of perfecting the mounting of difficult test objects.

Other modifications of this little instrument will readily sugest themselves to you. It is, to me, a great convenience to have a dozen of them at hand, of various sizes, as I can thus get my slides thoroughly seasoned under a perfectly uniform pressure-and I can have twenty of them made for the cost of one English compressor.

My friend, Mr. McAllister, Optician, 728 Chestnut St., Philadelphia, made them for me from a drawing, very neatly and accurately, at seven dollars and fifty cents per dozen ($7,5%).

Very truly, your friend,

Washington, Jan. 4th, 1860.

S. MORTON Clark.

3. On Contraction of the Muscles, induced by Contact with Bodies in Vibration; by O. N. ROOD, Professor of Chemistry in Troy University.— Some time since, when grinding a slide for microscopic purposes, as the strip from time to time accidentally came into vibration, I experienced, in the hand holding it, a numbness, and, at times, an absolute inability to relax the grasp. It seemed as though an involuntary contraction of the muscles had been effected by the vibratory action.

For the examination of this matter, the apparatus seen in the woodcut

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was devised: b is made to revolve at a rate of from 50 to 60 revolutions per second; rr is a rod of iron placed excentrically and so that the distance ra is equal to 4th of an inch. To protect the hand from blisters, the brass tube t encloses the rod, fitting it very loosely. When the hand is laid on this sheath, the rate of rotation being between 40 and 60 revolutions per second, a feeling of numbness is first perceived; the muscles involuntarily contract with considerable force, and the hand grasps the sheath tightly. As long as this rate of revolution is kept up, it is almost impossible, by an effort of the will, to relax the grasp, just as is the case with the electro-magnetic machine employed for medical purposes. The sensations, indeed, resemble those occasioned by the use of this apparatus, and usually extended as high as the elbows. At the termination of these experiments no particular inconvenience was experienced, although the sensations produced by the higher rates of vibration were painful.

Experiments were made on different parts of the arm and hand. The results obtained differed in degree rather than in kind.

The resemblance of the symptoms and sensations produced by electricity and mechanical vibration, is at least singular, and may eventually throw some light on the method in which electricity causes contractions in the muscles.

Troy University, Feb. 3d, 1860.

4. Large Object-Glass.-Messrs. Alvan Clark & Sons, of Boston, have completed on their own account, an object-glass with a focal distance of sixteen feet, and clear aperture of twelve inches. It has a nice defining power, and Mimas, the nearer satellite of Saturn, was seen with it Feb. 14th and March 24 and 4th.

5. Boyden Premium.-URIAH A. BOYDEN, Esq., of Boston, Mass., has deposited with the Franklin Institute, Philad., the sum of one thousand dollars, to be awarded as a Premium to "any resident of North America, who shall determine by experiment whether all rays of light, and other physical rays, are, or are not transmitted with the same velocity."

The conditions are given in an advertisement at the end of this Number. 6. Geological Survey of California.-We learn that a bill for secur ing the geological survey of California is now under consideration and if not so already, is likely soon to become a Law. So important an act must meet with the approval of every one interested in the material prosperity of the golden state: while science has much to expect every way from the proper discharge of such a commission.

SECOND SERIES, VOL. XXIX, No. 87.-MAY, 1860.

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