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gathered a very extensive collection of insects, numbering, as he assures me, many thousands of species. This collection is

now owned by Mr. Smith, and it is of so great value that I feel it my duty to call the attention of your Excellency to the matter, suggesting that it may be advisable to take steps toward securing at least a complete set of the species for the National Museum.

In accordance with the request of your Excellency, I accepted the Directorship of the geological section of the National Museum. After inaugurating the plan and arranging the work for my assistant during my absence, I propose to leave the city to continue my studies in the north.

My prospective journey is as follows: to leave Bahia for the diamond fields, and after examining these to proceed as far as the Rio Sao Francisco, to a point not yet determined. I intend to visit the watershed between the Sao Francisco and Tocantins rivers and to determine its character, afterward descending the Sao Francisco to the vicinity of the rapids of Paulo Affonso. From thence I expect to make a trip to the Serra de Araripe, and then to visit the locality of fossil fishes to examine the Serra de Ybiapaba, striking the sea coast probably at Ceará.

After making this expedition and reviewing the work of the assistants, who will be left along the coast in the provinces of Bahia, Sergipe and Alagoas, I ought to have a somewhat clear idea of the general geology of the northeastern portion of the empire, a region concerning which we have now very little information. This journey will probably occupy about four months. At the close of the exploration I propose to return to Rio de Janeiro with the members of the Commission to arrange and describe the collections and to prepare a report in extenso upon all the results obtained by the Commission with descriptions and engravings of a large number of Brazilian fossils.

ADDENDUM BY THE TRANSLATOR.

A letter received from Professor Hartt, bearing date, Rio de Janeiro, March 25, 1876, gives some particulars concerning the work accomplished since the writing of the foregoing report. He states that Messrs. Derby and Rathbun have met with most excellent results at Bahia, while Dr. Freitas and Mr. Branner have made yet another very large collection of Cretaceous fossils from the Maröim region. Mr. H. H. Smith had also done characteristic work upon the Amazonas, amassing extended and valuable collections. Professor Hartt himself was about ready to start for the interior.

By the same mail a letter was received from Mr. O. A. Derby, dated Santo Amaro, near Bahia, March 26, 1876. He writes: "We have found some rich deposits of Cretaceous fishes and

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reptiles in this vicinity and are working them up with care. do not know as yet what we have, but am certain of several species of Crocodiles and think we have Iguanodon. Branner reports quantities of fine Cretaceous fossils from the Province of Sergipe, where he is now."

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"We are now engaged in an exploration of the bay [Bahia de Todos os Santos] and are in a little town four hours by steam from the city [Bahia]. The geology of this vicinity is mainly Cretaceous and Tertiary and quite interesting, though one should have a dozen pairs of eyes to study it. Sections are hard to find and when found more difficult to understand properly. The rock is much decomposed and about a dozen different things present almost the same appearance when in a state of decomposition."

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"I have visited a diamond locality. in gravel which is either late Tertiary or modern."

They occur

A collection of Brazilian auriferous ores, Professor Hartt writes, will be exhibited at the Centennial Exposition in Philadelphia. The friends of the Professor will be pleased to learn that he has removed with his family to the mountains back of Rio, where all are safe from the ravages of the yellow fever.

Letters for the members of the Commission should be sent enclosed to Major O. C. James, Secretario do Commissao Geologica, Caixa no Correio No. 126, Rio de Janeiro, Brazil, to whom all business connected with the survey may be entrusted. Questions which can be answered by the undersigned will receive due attention. THEO. B. COMSTOCK.

Ithaca, N. Y., May 5, 1876.

ART. LXIV.-Notice of the Meteoric Stone of Waconda, Mitchel County, Kansas; by CHARLES UPHAM SHEPARD, Sr., Massachusetts Professor of Natural History in Amherst College.

FOR my first knowledge of the meteorite of Waconda, Kansas, I am indebted to Dr. George W. Chapman of that place. This gentleman wrote me on the subject during my absence from the country the past summer, and it was not until lately that the correspondence was renewed which has led to the information now afforded. From his letters and a few grams of the stone transmitted by post, I am enabled to give the following partial description,-reserving a fuller account until my return to the north, when I expect to receive the large mass from which the fragments sent were detached.

The stone was found two years since, lying above ground, in the grass, upon the slope of a ravine, at the distance of two

miles from the village of Waconda. Many pieces were then broken from the mass, leaving about one-half, whose present weight is fifty-eight pounds, half of which is still covered by the original crust. The specimens transmitted show a freshness. equal to that of any newly fallen stone, although they came from the immediate surface,-a circumstance obviously pointing to the recentness of the fall. I have known instances where stones exposed only a few weeks to the weather have suffered a decided oxidation, whereas no such change seems to have occurred in this case.

Its cohesion is about that of the average among meteoric stones. In this respect, as well as shade of color, it corresponds very nearly to the Searsport (Me.) stone, of May 21, 1871; but in structure it differs by being less oolitic. Indeed, it is only obscurely so at all, the individuals that are distinct being rather granular, often with well-marked angles, some of which suggest the species augite; others, those of forsterite (variety boltonite). There is considerable amorphous whitish matter interposed among the grains (in which they may be said to be imbedded), which is doubtless a mixture of minerals, and may consist of chladnite with some one or more of the feldspars. The chamasite (nickelic iron) is present in thickly scattered, very minute, rounded, lustrous grains, requiring for the most part the use of a lens for their discovery; while the troilite (magnetic pyrites) is now and then seen in considerable grains, or ovoidal aggregations of imperfect crystals. The crust is rather thicker than usual, of a dull iron-black color, with a slight tinge of brown, and much crumpled or reticulated. The specific gravity of a fragment weighing 4:35 grams (of which twofifths were covered by crust) is 3-810; that of a fragment without crust, weighing 3.57 grams, is 3:58.

By mechanical analysis the stone gave 5.66 per cent of chamasite, and 1.34 per cent of troilite. The earthy portion was rather more than one-half decomposed by aqua regia, the soluble portion, after the separation of the silica, giving magnesia, and protoxide of iron (with a little lime) in the usual proportions of chrysolite. The matter not attacked by acids probably belongs to augite, some feldspathic species, and chladnite.

There exists a rumor that a second stone has been found, twelve miles distant from the first; but it lacks confirmation.

It is very likely that the exact date of this meteoric fall will yet be ascertained, inasmuch as it must have taken place very lately, and, without doubt, was attended with a notable report.

Charleston, S. Car., March 16, 1876.

ART. LXV.-- Paleozoic subdivisions on the 40th Parallel; by CLARENCE KING.

THE geological exploration of the fortieth parallel has covered an east and west section of the Cordilleras from the 104th to the 120th meridian, or from the east base of the Rocky Mountains to the eastern boundary of California, along the fortieth and forty-first parallels. The belt of territory under examination is a little over one hundred miles from north to south. Over the greater part of this area bodies of Paleozoic rocks are observed at intervals. A considerable study of these more or less detached exposures, together with the final determination of a large collection of molluscan fossils, has rendered it possible for us to correlate the various members of the series, and construct with considerable precision a complete Paleozoic section. It is the object of this paper to announce the stratigraphical divisions established in the field, and their relation to the Paleozoic subdivisions as established in New York and in the Mississippi basin.

It may be well to remark that along our eastern boundary, in the region of the Rocky Mountains, the entire Paleozoic series-including Coal-measure beds and strata bearing Potsdam fossils are embraced within a section from 900 to 1200 feet, the whole entirely conformable and resting discordantly upon an Archæan foundation. In passing westward the series rapidly expands from 1,000 to 32,000 feet. Lithologically, divisions which were lost in the narrow Rocky Mountain Paleozoic zone are established with great volume and persistency over wide areas in Utah and middle Nevada. Finally, in the neighborhood of Battle Mountain, at longitude about 117° 25', an Archæan land-mass rose to the west of the Paleozoic ocean, interrupting farther continuance in that direction.

The region of the Rocky Mountains represented Archæan islands and shallows, around and over which the sparing sediments were deposited, while toward the westward the general contour of the Paleozoic ocean deepened over a broad basin, which probably continued to a great depth quite against the western shore in longitude 117° 30'. To the southward, from the well-known observations of Dr. Newberry and others, it is evident that this Paleozoic sea very perceptibly shallowed. The northern configuration of the bottom and the depth of the Paleozoic series in at present unknown. It is a striking fact, that wherever, within the limits of this exploration, exposures are made, and they are very frequent,-from the Primordial to the summit of the Coal-measures, there is never the slightest unconformity between the various members of the series. The

key to the subdivision of the whole Paleozoic is obtained in the Wahsatch Range, where I have observed a single section of about 30,000 feet of conformable rocks extending from the Permo-carboniferous strata, conformably underlying the red sandstones of the Trias, down to low exposures of the Cambrian.

Ignoring such minor subdivisions as we find to be very variable and local, and describing only such as are observed to be persistent and widespread, I will note in their order from the base of the Cambrian upward the important stratigraphical subdivisions, with their position in the New York scheme.

The lowest member of the series consists of a group which rests non-conformably upon the Archæan, and consists of three prominent members: the lowest is a series of siliceous schists and argillites, best exposed at the mouth of Big Cottonwood Cañon, in the Wahsatch Range, and having a total thickness of from 800 to 1,000 feet; over this is a series of quartzite and quartzofeldsitic strata, having limited beds of slate interspersed through it and containing near the top some dark micaceous zones, the whole reaching in Cottonwood Cañon a thickness of over 12,000 feet: the uppermost member is a narrow zone of variable argillites, calcareous shales, and thin, slightly siliceous limestones having in the Wahsatch an extreme thickness of seventy-five feet. The shaley zone and the accompanying slates carry fossils of well-defined Primordial types, but the quartzite and the deep-lying slates have not yet yielded any organic forms. We have therefore in the Wahsatch a series of 12,000 feet, of which the thin summit member carries Primordial fossils, and the vast underlying series is thus far barren. Comparing the quartzites and argillites with those of the Cambrian section in Wales, the likeness is too great to pass unnoticed, and in view of the enormous developments of these low-lying rocks, as compared with the Silurian lying above the Primordial horizon, I have determined to draw a line at the upper limits of the Primordial period to include the uppermost members of the Potsdam epoch, and to consider the whole underlying conformable series as Cambrian down to the point of their non-conformity with the Archæan. In the extreme east of our work, in the region of the Rocky Mountains, the Cambrian formation is of variable thickness and nowhere reaches an exposure of over 100 feet. In middle Nevada the uppermost zone of the Cambrian, equivalent to the calcareous and argillaceous shales of the Wahsatch, is an immense body of dark limestones at least 3,000 feet in thickness carrying Primordial fossils throughout; the downward continuation of the series being there entirely hidden by the overlying Quaternary desert. The fossils obtained by our survey from the Cambrian series are as follows:

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