highest mean monthly temperature seems to occur almost exactly in the middle of July, and the lowest point would probably have been found in February if the series had been extended over several winters. The mean temperature of winter, namely, of December, January, and February, was -28°.59; of spring, -10°.59; summer, +33°.38; autumn, -4°.03. The mean temperature for the whole year was -20.46. The temperature was always lowest during calms, and rose with the springing up of a wind from any quarter.

There is also a great regularity in the elevation of temperature during the hours of the fall of snow; on an average the sensible heat was increased during this period 7°.7. In seventeen months it snowed during six hundred and eighty hours, and rained during sixty hours.

A series of recurring periods of cold was observed, which Dr. Kane seemed inclined to consider as intimately connected with the phases of the moon, and on this point a series of elaborate investigations was made by Mr. Schott, from which it was found that in a period of six days on an average the cycle was completed, and that the lowest temperatures are reached about the time of full moon. Setting aside some small deviations in the regularity of the curves of temperature, there is not a single exception to the correspondence of the greatest cold near the epoch of full moon, and of least cold near the time of the new moon. It should be observed, however, that since, from the observations made at this Institution, the waves, as it were, of cold air which reduce the temperature of the United States, frequently begin several days earlier at the extreme west, the same coincidence as to identity of occurrence of the maximum cold with any particular phase of the moon cannot be true of all points on the surface of the earth, although the period of recurrence may, as in the case of the tides at different places, be governed by that luminary.

A series of comparative observations at the level of the sea and at the top of the mast of the brig, at eighty feet elevation, was taken during the months of August, September, and October, from which is deduced a diminution of temperature of 1° for two hundred and ten feet of elevation.

The direction of the wind was noted in the original records with reference to the magnetic points of the compass, and the mean results

determined in regard to the true north. It appears from all the observations that the true direction of the wind is from the eastward, varying in the several months northward and southward. There is but one exception, namely, in June; the wind then veers round to the westward of south. The resulting direction for the whole year is almost exactly east; in winter it is E.N.E. and in summer S.E. by S. The greatest quantity of air which moves over the place during the year comes from a direction north of east.

The predominance of calms is a circumstance quite characteristic of this region. The number of hours of winds recorded was 3,697, and those of still weather 5,063.

The snow or rain wind is between N.N. E. and E.S. E., or from the direction of the Spitzbergen sea, and also from the opposite direction of S.S. W., or that of the upper Baffin's bay. From the northwestern quarter there was hardly any precipitation.

During the whole period there were recorded thirteen gales, with a duration of not less than two hours. They do not appear to be confined to any particular season of the year, and on the average continue about seven hours.

These records are of great interest in enabling us to ascertain whether the great storms which pass over the United States can be traced into the Arctic regions.

For observations on atmospheric pressure the expedition was provided with a mercurial barometer and two aneroids, and from a series of reductions of the observations of these instruments it is concluded that the indications of the aneroid may generally be relied on to within nearly one hundredth of an inch.

Owing to the small amplitude in the oscillations of the barometer, and the magnitude of occasional disturbances, the law of diurnal variation is apparently subject to considerable fluctuations. The principal maximum is reached about one o'clock p. m.; the evening maximum at about ten p. m., in conformity with the general law deduced from observations in the northern hemisphere. The one p. m. minimum seems to occur about three hours earlier than is indicated at more southern stations.

The average maximum height of the barometer is above the mean in the months of January, February, March, April, and May, and descends below the mean in the remaining summer and autumn months. The general law observed in other parts of the world, that the height

of the barometer is less in summer than in winter, is prominently exhibited.

The mean height of the barometer for the whole time was 29.775 inches, which is less than that for places under the tropics; and it should be stated that Van Rensselaer harbor is fourteen degrees farther north than the latitude 64° in which the height of the barometer is a minimum.

The fluctuations in the height of the barometer were greater in winter than in summer. The greatest pressure, 30.97 inches, occurred in the morning of January 22, 1855; the lowest, 28.84 inches, occurred near noon of February 19, 1854. Little change was ob served in the barometer during the fall of snow.

The barometer fell during the blowing of all the winds except those from about north by east and southeast.

The observations indicate that the hottest winds are from the northeast, one-half east, and the maximum atmospheric pressure nearly

east.

This memoir was referred for critical examination to Professor Peirce, of Cambridge, and Professor Chauvenet, of St. Louis.

The next memoir is by Dr. John Le Conte, of Philadelphia, and is intended to give a catalogue of the Coleoptera or beetles known to inhabit the middle and eastern portions of the great central region of temperate North America. The province here treated of includes Kansas, a portion of Nebraska, and the eastern part of New Mexico. Its eastern limit is well defined, but its other boundaries are indefinite, since it there fades imperceptibly into other provinces of the same great zoological district. The descriptions of new species are principally from specimens furnished through the Smithsonian Institution from collections made by different explorers connected with the surveys of the officers of the United States army.

Before proceeding to describe the special materials used in the preparation of the memoir, the author gives a short sketch of the results already obtained in regard to the geographical distribution of coleopterous insects in this country, illustrated by a map on which the several regions are distinguished by different colors. From this map it appears that the whole area of the United States is divided by nearly meridianal lines into three or perhaps four zoological districts, distinguished each by numerous peculiar genera and species, which, with few exceptions, do not extend into the contiguous districts.

These districts are divided into a number of provinces of unequal size, which are limited by differences in climate, and are therefore sometimes distinctly and sometimes vaguely defined.

The mode of distribution of species in the Atlantic and Pacific districts is entirely different. In the Atlantic districts a large number of species are distributed over a great extent of country; many species are of rare occurrence, and in passing over a distance of several hundred miles but small variation will be found to exist. In the Pacific district a small number of species are confined to a limited region of country. Most species occur in considerable number, and in travelling even one hundred miles it is found that the most abundant species are replaced by others, but of a similar character.

The object of the memoir is to give an account of what is known of this class of insects in Kansas, upper Texas, and Arizona, and to furnish means for facilitating the further exploration of the whole country in regard to the same animals.

This will undoubtedly be considered a valuable addition to a branch of zoology which, however insignificant it may appear to the popular mind, is not only connected with questions of interest in relation to abstract science, but also with the economical resources of the country..

The memoir, beside the colored map to which we have alluded, is illustrated by two engraved plates.

The next paper consists of the result of magnetical and hypsometrical observations in Mexico, to which is appended notes on the volcano of Popocatepetl and its vicinity.

In 1856 Baron Von Müller undertook an exploration of Mexico in reference to its natural history, and proposed to the Smithsonian Institution to make in its behalf a magnetic survey of the same country. This offer having been accepted, an appropriation was made from the Smithsonian fund to pay a portion of the salary of Mr. Sonntag, the assistant of Baron Von Müller; and the magnetic instruments which had been previously lent to Dr. Kane, and used by Mr. Sonntag himself, as one of the assistants of that lamented explorer in his last Arctic exploration, were furnished to the expedition for the contemplated survey. Several records of the unreduced observations made at a number of places in Mexico, were at different times transmitted to the Institution previous to the return of Baron Von Müller to Germany, after which nothing more was obtained; and after considerable delay

we were informed by him that he had been robbed in Mexico, and that the instruments had been captured and destroyed. Not having received a final report from Baron Von Müller, to render the observations which had been obtained from Mexico available to science, they were placed in the hands of Mr. Sonntag on his return to Washington, and have been reduced by him at the expense of the Institution. He has also appended a series of notes relative to the volcano of Popocatepetl and its vicinity, and also a series of barometrical and trigonometrical measurements of heights of various places in the vicinity of the city of Mexico. The observations included those for the declination or variation, the inclination or dip, and, lastly, those for the relative intensity of the magnetic force. A series of observations for each of these elements was made at the following places, namely, Vera Cruz, Potrero, Cocolapam, San Andres, Mirador, city of Mexico, Chalco, and Tlamacas. The average variation of the needle from the whole series of observations was about 81° east; at the city of Mexico it was 8° 46' east. The average dip for the whole region was about 4210, and for the city of Mexico 41° 26'.

The interesting fact is noted in the appendix that the southwestern wall of all the recent Mexican craters observed by the author is higher than the northeastern wall-a phenomenon probably due to the action of the trade-winds constantly impelling the ashes and cinders from the northeast to the southwest. The elevation of eleven different places was determined, including the city of Mexico and the highest peak of Popocatepetl. The former was 7,472.8 feet, and the latter 17,817.6 feet.

We regret very much the loss of the magnetic instruments, not only on account of the use which might be made of them in determining the magnetic elements of different portions of the American continent, but also on account of the interest which attaches to them from having been employed in the observations by Dr. Kane. They have, however, done good service; and although the result of the co-operation of Baron Von Müller has not been as fortunate as we could have wished, still it has added something of considerable value to our knowledge of the terrestrial magnetism of this continent.

Another memoir, which will form a part of the 11th volume of "Contributions," is on the American storm of December 20, 1836, and the European storm of December 25 of the same year, by Professor Elias Loomis, of the University of New York.