and Mr. W. M. Gabb. It thus appears that Prof. Whitney has called to his aid the best available talent in working out the results of the survey in special departments. Meantime, the fieldwork, and the elaboration of the geological and topographical data collected, are going on rapidly under his direction.

The necessity of preparing maps for the accurate delineation of the geology of a vast state of almost unknown geography, has led to an expansion of the topographical work far exceeding what was anticipated, and constituting a step of very great importance in the history of American geography. Accurate detailed maps, from actual surveys, of extensive inland regions, including grand mountain features, had not been produced before in the country, at least on anything like the same scale. Nor has the beneficial activity of the survey in this direction been limited to California; the survey of the 40th Parallel is to be accounted one of its fruits, the two heads of the latter, Messrs. King and Gardner, having begun their Western work in California under Prof. Whitney, and undertaken their survey in continuation and completion of his. Of the maps of the California survey, there have appeared hitherto those of the Yosemite valley and of the High Sierra in its vicinity (in the Yosemite Guide Book), and that of the region adjacent to the Bay of San Francisco, the last on a scale of two miles to the inch; a much larger map, including about 60,000 square miles of the central part of the State (occupied by more than nine-tenths of its population), is far advanced, one of its four sheets (the S.W. corner) being already engraved, and a second (the S.E. one, containing the highest part of the Sierra) in the engravers' hands. This is on a scale of six miles to the inch; it will be issued in duplicate, as geological and as a topographical map. Another, of the whole State, at eighteen miles to the inch, is finished, and is intended to serve as a preliminary geological map, and to accompany the second volume of geology, of which the printing will be begun next summer. Among the regions which have been recently receiving particular attention is that of the ancient riverchannels, on the western slopes of the Sierra, which a party has for a long time been engaged in exploring and mapping, and on which a full report is soon to be made; also, the White and Inyo ranges of mountains, east of the Sierra and of Owen's valley; and the vicinity of Clear Lake, in the northern coast ranges.

We cannot express too strongly our sense of the importance of this survey, and of its value to the people of the whole country as well as of the State which it particularly concerns. That, after its temporary suspension (1868-70), it was taken up again and vigorously pushed, is highly creditable to the enlightenment of the California people; and it is not to be believed that they will again falter in the support of a work which is bringing them so much honor throughout the world, and helping to lay a sure foundation for the future successful development of the resources of the State.

2. Geological Survey of Illinois: A. H. Worthen, Director. Vol. IV. Geology and Paleontology. Geology, by A. H. WORTHEN, and Assistants H. M. BANNISTER, FRANK H. BRADLEY and H. A. GREEN: Paleontology, Section 1, Descriptions of

Vertebrates, by J. S. NEWBERY and A. H. WORTHEN; Section 2, Description of Plants, by LEO LESQUEREUX. 508 pp. royal 8vo, with 31 plates.-Much has been done in this country in the way of Geological Surveys. Yet only two States east of the Rocky Mountains have carried forward such surveys to anything approaching a worthy completion. These two States are New York and Illinois. Fortunately they supplement one another, so that a geologist, by possessing the reports of the two, when they are finished, will have quite a good account of the rocks and fossils of the whole range of the Paleozoic formations of the country. New York carries forward the subject to the Coal formation, while Illinois gives much that is new from the earlier limestones, and continues the geology through the Carboniferous period, in which part of the series the State is particularly rich.*

The fourth volume just issued is, like its predecessors, a handsome volume, and full of valuable material. Most of the counties here reported on are within the coal basin; and the reports are full of local details of Coal-measure sections-highly important to the local student and to capitalists interested in coal and iron, but including few matters of general interest. A hasty glance shows that the coal tonnage of these counties is immense, being approximately as follows:-Adams county, 830 millions of tons; Brown, 400 millions; Schuyler, about 1750 millions; Fulton, 7000 millions; Morgan, 3000 millions; Cass and Menard, 4000 millions; Tazewell, McLean, Logan and Mason, 30,000 millions; Grundy, 900 millions; Will, 66 millions; Kankakee, 40 millions; Vermillion, 4000 millions; Edgar, 6000 millions; Champaign and Ford, 10,000 millions: total, 70,000 millions of tons.

As matters of especial scientific interest, in the county reports, we note particularly various details and discussions touching the Loess; the Drift, with its included or antecedent beds of ancient swamp muck; the shallow artesian wells of the gravel of Iroquois county; the ancient channel [probably of a glacier] now filled with Drift, which runs south from the southern extremity of Lake Michigan; the outlines, level and drainage of "Lake Kankakee;" and the old outflow of Lake Michigan by the valley of the Desplaines and Illinois rivers. It is to be regretted that a map proposed for the purpose of showing details on these latter points could not be published with the volume, "for the lack of means to defray the expense of engraving," even though "the most essential parts of it will be transferred" to the large map of the entire State, now in course of preparation. Details are given, touching the unconformability of the Coal measures with the Subcarboniferous, and of the Devonian (or Subcarboniferous) with the Silurian.

The most of the other States have had surveys in progess; but, in general, in spite of the earnest protest of those interested in the work, they have been cut short when only a fair beginning had been made. Pennsylvania has done the best among these States; but still its extended Report, very valuable as far as it goes, includes no volume illustrating with plates the fossils of its rocks, the Coal plants excepted. Massachusetts has done much, but there is much more to be done; and the same is true of other States.

The equivalency of the different coals of the Illinois and Wabash valleys seems to be still in question; and we shall look with great interest for the thorough discussion of this subject which Prof. Worthen will doubtless give before closing his work.

The second part of this volume is occupied with descriptions and plates of fossils--Fishes and Coal-plants. Many new and interesting forms are described and figured. Prof. W. also notes the existence in his collections of enough of ichthyic fossils, as yet undescribed, to carry his catalogue of Illinois Carboniferous fishes to "something over two hundred species."

Mr. Lesquereux, after describing many new Coal-plants, and adding much to our knowledge of previously-described species, closes with an interesting discussion of facts regarding our American Coal-flora, which we shall notice more fully hereafter.

Prof. Worthen promises to complete this series of reports with two more volumes, most of the material for which is ready for the printer. We learn that the fifth volume will contain plates of the most important and beautiful series of Carboniferous crinoids and other echinoderms that has ever been figured or described. Very many of the figures have been carefully drawn, with many details of their structure, by Mr. F. B. Meek, and the remainder by Mr. Charles K. Worthen (son of the Director of the Survey), under Mr. Meek's direction. Including some of fishes there will be about forty plates.

3. Burning of the State Geological Rooms at Springfield, Illinois. On the night of the 22d of February, (after the 4th volume of the Illinois Geological Report, above noticed, was received by us,) the building containing the State Geological Rooms and Collections was burned. The fire took in a book-bindery adjoining, and, "in five minutes after the alarm was given, the upper part of the building was a sheet of flame." Prof. Worthen's son, who was sleeping that night in the office, succeeded in removing all his father's library and private cabinet, before it became necessary for the engines to play upon the building. The State Collections, which contained the most complete series of Carboniferous fossils in the country, if not in the world, besides numerous other species, and many kinds unknown elsewhere, were greatly damaged by water and by hasty removal, and very many fine specimens were ruined. Since the fire they have been transferred to the basement of the new Post-Office building, which, as it is fire-proof, is safe against such disasters, and where they ought to have gone long before the fire. Fortunately, the copies of the 4th volume were in the hands of another book-binder and escaped. This is another warning to all States, Societies or Institutions, having valuable collections, libraries or records; there should be no rest among the friends of learning until fire-proof buildings are provided for such objects. The money argument, that such a collection as that of Illinois would bring in the market over $20,000, has much force. But this amount in dollars is only a fraction of the real value to science, or to the people of Illinois.

4. Report of the Geological Survey of Iowa, under Prof C. A. WHITE, Vol. II, 444 pp. 8vo. The first volume of this report is noticed on page 217. The second volume contains a well prepared and instructive chapter, of 186 pages, on the Geology of the Middle region of Western Iowa and other counties by O. H. St. John, and reports on northwestern, and the middle region of northern, Iowa, and on the Coal counties, by Professor White, occupying nearly 100 pages. Prof. White next treats of the economical products of the State, exclusive of coal. Then follows the valuable chemical report of Prof. Rush Emery, containing analyses of rocks, coals, peats, etc. Those of coals are numerous; they have special reference to the economical value of the coals, and give the amount of moisture, volatile combustible, fixed carbon and ash. Prof. Emery compares the analyses with those of the coals of Illinois, and observes that the amount of moisture is perhaps a little in favor of the Iowa coals; the amount of ash is almost the same; that of fixed carbon is largely in favor of Illinois; while that of the total combustible matter is in favor of Iowa. The volume closes with a table of altitudes, and a catalogue of birds. The volume contains also a colored geological map of the State by Prof. White.

5. Historical notes of the Earthquakes of New England, 1638 -1869; by WILLIAM T. BRIGHAM, A.M., A.A.S. 28 pp. 4to. From the memoirs of the Boston Society of Natural History, vol. ii, page 1.-This important memoir by Mr. Brigham aims to give a list of all the well authenticated earthquakes that have occurred in New England, with such notes as could be gathered from the records of the time. The number catalogued as having been felt over New England since 1638, eighteen years after the landing of the Pilgrims at Plymouth bay, is 227. Besides these, four earlier ones are mentioned from the traditions of the Indians. These were distributed through the months as follows:

Oct., 19; Nov., 29; Dec., 22; Jan., 20; Feb., 36; Mar., 22--148 April, 9; May, 13; June, 14; July, 13; Aug., 15; Sept., 10. 74 No month given,.

9

A considerable number of these earthquakes were felt over all New England, some of them also over Canada, and a few had wider limits. Many of them were comparatively local in their range. Three such local regions are deduced by Mr. Brigham from the catalogue. These are-1. A region in Canada, somewhat elliptical in form, with the city of Montreal as its western focus. 2. A region around the mouth of Merrimack river, in New Hampshire and Massachusetts and extending to Boston. 3. A region smaller than either of these, around New Haven, Lyme and East Haddam. The author makes some suggestions with regard to the origin of the earthquakes, proposing to take up the subject in full at another time. He thinks it probable that there have been volcanoes somewhere in New England, prefacing his remarks by the statement that our Geological Reports have often been prepared by those who had never studied active and extinct volcanoes, and adding a remark implying that if Percival had ever seen a vol

cano," he would have found them in the trap region of Connecticut. In reply to this we would state that no region of igneous rocks, volcanic or otherwise, was ever studied with more care, or with a more exact determination of the facts, than that of Connecticut by Percival. We have followed him over and among the various trap ridges of the Connecticut valley, and know positively that the trap eruptions were in all cases, eruptions through fissures, as Percival states, and not by volcanoes. We deprecate this throwing doubt over the accurate observations of others, by one who acknowledges that he knows nothing about the facts.

There are beds of scoriform rock in the Connecticut valley among the stratified beds in the vicinity of the trap. They occur near New Haven. A remarkable locality exists in Durham, on the Air-line railroad, under a bridge just east of Reed's Gap (a gap in the trap hills). At this place, the layer seems to be made up of large masses of scoria, some of them from four to six inches in diameter. But on a careful examination by the writer, the rock proved to be nothing but a scoriform sandstone, particles of quartz, feldspar and other ingredients of the Mesozoic sandstone being visible throughout the scoria masses, and manifestly constituting them. It is obviously a bed, like others at New Haven, through which steam penetrated freely during the trap eruption.

Mr. Brigham also suggests that the formation of trap dikes may now be going on, from time to time, at various depths below the surface; and "that the high temperature they bring in contact with the cold rock, through which they break, or into whose cavities they run, produces the tremors and disturbances we call earthquakes." But there is not an observed fact that authorizes us to believe that any eruption of trap has taken place in New England since the Mesozoic era. Moreover, earthquakes are not produced by the escape of igneous rock. An earthquake is the jar from sudden fracture or displacement; it matters nothing whether igneous ejections follow or not. The breaking of the rock begins the "tremor" if not already initiated. The earthquakes of New England may have resulted from a slight yielding to tension in the rocks somewhere beneath the region sbaken, a tension that may be a consequence of former upheavals or subsidences of the region, or of unappreciated movements that are now in progress; or possibly of contraction or expansion below due to subterranean change of temperature; and some of the more local may come from a yielding to gravity in rocks beneath, if openings or cavities there exist.

J. D. D.

6. Preliminary notice of a new species of Trimerella, from Ohio; by F. B. MEEK. (Communicated by the author).-Among the fossils obtained by the Geological Survey of Ohio (now in progress under the direction of Prof. Newberry), and handed me for study, there are from the Niagara group some large casts of a Trimerella, which I had thought might be a variety of T. grandis Billings. On comparing them recently with Mr. Billings's typical specimens of that species, I have found them quite different and distinct. They are proportionally much broader shells, and differ in having the beak of the dorsal valve strongly incurved beyond