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horizon.1 Messrs. Hayden and King have discovered it west of the Wasatch range in Utah and Nevada, and Marsh has observed it in Oregon. Messrs. Dana and Grinnell found it occupying the valley of Deep river in Montana, and Professor Mudge any myself have seen it in Northern and Western Kansas. There is a near lithological resemblance between the strata at these localities, and the fauna presents a common character as distinguished from those which preceded and followed it; but sufficient care has not always been exercised to distinguish its upper members from the Equus beds above them. The latter contain a distinct fauna.2

According to King, about 1500 feet of beds are included in this formation.

The water-shed between the South Platte river and the Lodge Pole creek, Colorado, is composed superficially of formations of the Loup Fork epoch, of Hayden. On its southern side is an abrupt descent in the level of the country, which generally presents the character of a line of bluffs varying from 200 to 900 feet in height. This line bends to the eastward, and extends in a nearly east and west direction for at least sixty miles.

The upper portion of this line of bluffs and buttes is composed of the Loup Fork sandstone in alternating strata of harder and softer consistency. It is usually of medium hardness, and such beds, where exposed, on both the Lodge Pole and South Platte slopes of the water-shed, appear to be penetrated by numerous tortuous friable silicious rods and stem-like bodies. They resemble the roots of the vegetation of a swamp, and such they may have been, as the stratum is frequently filled with remains of animals which have been buried while it was in a soft state. No better preserved remains of plants were seen.

This formation rests on a stratum of white friable argillaceous rock of the White River epoch, as represented in Fig. 7.

The lithological characters above described are precisely those presented by the same formation in New Mexico.3

Mr. King employs the name Niobrara for this formation, but Dr. Hayden's name was introduced many years previously. The

1 Ann. Rep. Chief of Engineers, 1874, II, p. 603.

2 See Bulletin U. S. Geol. Surv. Terrs., IV, p. 389, and v, p. 47.

3 See Report Lieut. G. M. Wheeler's Explorations west of 100th Meridian, Vol, IV, p. 283.

'See Dana's Manual of Geology, edit. 1864, p. 511.

new name has also the disadvantage of being already in use for a horizon of the Cretaceous, which is well distinguished palæontologically.

Some genera of Rodentia are common to this formation and the White River (Steneofiber, Palæolagus), but its fauna is well distinguished by the presence of Camelida with a cannon bone, three-toed horses with cementum in the molars, Antelope with a burr of the horns (Cosoryx) and Mastodon.

I have divided the Loup River formation into two divisions on palæontological grounds,1 under the names of the Ticholeptus bed, and the Procamelus bed. The former occurs in the valley of Deep river, Montana, on the White river in Northern Nebraska, and in Western Nebraska, where it has been found by Mr. Hill. Its fauna presents, in Montana, a mixture of fossils of the Procamelus horizon; while in Nebraska, according to Hayden, its typical genera are accompanied by White river Mammalia. In the former region, Hippotherium, Protohippus and Blastomeryx are mingled with genera allied to Leptauchenia and with Merycochorus. In Nebraska, Leptauchenia is said to be accompanied by Ischyromys, Palæolagus, Hyracodon and even Oreodon, genera which do not extend to the Procamelus bed. There is, however, a question. in my mind whether this collocation is entirely correct. It is bed D of Hayden's section in Leidy's Extinct Fauna, Dakota and Nebraska, p. 20.

The material of the Ticholeptus horizon is a more or less friable argillaceous sand; not so coarse and gritty as the Procamelus bed, nor so calcareo-argillaceous as the White River.

The Procamelus bed is extensively distributed. It is found in Kansas, Nebraska, Colorado, New Mexico, Utah, Nevada and Oregon.

THE EQUUS BEDS.

I can give little information respecting the depth and stratigraphy of the beds of this period as they occur on the plains west of the Mississippi river, for although sections of them as they occur in Nebraska and elsewhere have doubtless been published by authors, their palæontological status has not been determined. for the localities described. My own knowledge of the deposits. is based on localities in California and Oregon. In Nebraska they have probably been confounded with the Loup Fork beds. They 1 Bull, U. S. Geol. Surv. Terrs., V, pp. 5c-52.

[blocks in formation]

represent the latest of all the Tertiary lakes, and include a fauna which consists of a mixture of extinct and living species, with a few extinct genera.

I have received fossils of this age from Idaho, Washington, Oregon and California. The most important locality in Central Oregon is from thirty to forty miles east of Silver lake.1 The depth of the formation is unknown, but it is probably not great. It consists, first, of loose sand above, which is moved and piled into dunes by the wind; second, of a soft clay bed a few inches in thickness; third, by a bed of sand of one or two feet in depth; then a bed of clay mixed with sand of unknown depth. The middle bed of sand is fossiliferous. In Northern and Middle California the formation is chiefly gravel, and reaches a depth, in

[graphic]

FIG. 8.-Sand hills, Northwestern Nebraska, from Hayden. some localities, of several hundred feet. Here, as has been proven by Whitney, it contains human remains, associated with Mastodon, Equus, Auchenia, etc. I have obtained Mylodon from the same gravel.

Traces of this fauna are found over the Eastern United States, and occur in deposits in the caverns excavated in the Lower Silurian and Carboniferous limestones, wherever the conditions are suitable. This deposit is a red or orange calcareous mud, varied with strata of stalagmite and gypsum. Remains of the fauna are found in clay deposits along several of the Atlantic rivers, as the Delaware and Potomac,

1 See AMERICAN NATURALIST, 1878, p. 125.

It is probable that the formation in the western localities mentioned is mostly sand, Near Carson City, Nevada, it consists of a light-buff friable calcareous sandstone,

This is the Upper Pliocene of King and the Post-pliocene of various writers,

:0:

A PATHOGENIC SCHIZOPHYTE OF THE HOG.1

BY PROFESSOR H. J. DETMERS.

ABOUT twenty-five years ago Professors Brauell and Pollender

in Dorpat, Russia, made an important discovery, which, though at first not considered as of much significance, soon led to investigations, the results of which have already revolutionized the etiology of contagious and infectious diseases. Brauell and Pollender, and soon afterwards also Dr. Leisering in Dresden, discovered in the blood of man and beast, affected with anthrax or splenic fever, an infinite number of exceedingly fine, apparently solid, almost transparent, straight and motionless, rodshaped bodies (cf. Virchow's Archiv. für Pathol., Anat. und Physiol., und für Klinische Medicin, XI, 2). They called them staebchenformige Koerper (Bacilli), but left it undecided whether the same bear a casual connection with the morbid process, constitute a product of the same, or are merely accidental. Still, finding these Bacilli in every fatal case of anthrax, Brauell and Pollender considered their presence as something characteristic, and as of great diagnostic and prognostic value. As early as 1860 the relation of these Bacilli to anthrax formed a topic of discussion in the annual meeting of the Veterinary Society of the Grand Duchy of Oldenburg. Later investigations, but especially those by Davaine, Koch, Cohn, Pasteur, Toussaint, and more recently by Dr. Hans Buchner, in Munich, have demonstrated beyond a doubt that these Bacilli, first discovered by Brauell and Pollender of the Imperial Veterinary School of Russia at Dorpat, and first known as Brauell and Pollender's staebchenfoermige Koerper, constitute the real and sole cause, and also the infectious principle, of that terrible disease known as anthrax or Milzbrand to the Germans, charbon to the French, and anthrax or splenic fever to the English. About the same time, or soon after Brauell and Pollender published their discovery, other simi1 Read before the Chicago Academy of Sciences.

lar microscopic bodies were found, not only in the blood and morbid products in contagious diseases, but also in a great many other things, particularly in putrefying, decomposing, and fermenting substances, in pus, secretions of wounds, in the mucus of the mouth, etc. All this, however, is well known, and as I do not intend to give a history of the discoveries in regard to these minute bodies, comprehended under the generic name of Schizophytes, nor dwell upon the investigations made by many European and some American scientists for the purpose of ascertaining the true character and the relation of those Schizophytes to contagious and so-called zymotic diseases, I will only make one further remark, and then briefly relate what I have seen and ascertained myself. I mentioned the discovery of Brauell and Pollender as a fit introduction to what I shall have to say, and also for the purpose of correcting certain erroneous statements in American literature, which ascribe the first discovery of Bacillus anthracis to Davaine, and to other French investigators. For a long time. it remained a puzzling question how certain Schizophytes, found in certain diseases in the blood, exudations, and other animal fluids, etc., can constitute the cause and infectious principle of those diseases, while other Schizophytes, apparently identical, or at least very similar in appearance, and of almost universal occurrence, are known to be perfectly harmless. To illustrate, it will only be necessary to mention the great similarity between Bacillus anthracis and Bacillus subtilis, two of the best known Schizophytes. This question has been solved by the researches of Dr. Hans Buchner in Munich (cf. his monography "Ueber de Experimentelle Erzeugung des Milzbrand Contagiums aus den Heupilzen, und ueber die Entstehung des Milzbrandes durch Einathmung, Muenchen, 1880"). Dr. Buchner, by repeated and continued cultivations in solutions of meat extract, with and without an addition of peptone and sugar, succeeded in converting Bacillus anthracis into Bacillus subtilis; 36 generations made the former harmless, and about 1500 generations converted the same into a veritable hay-bacillus or Bacillus subtilis. Vice versa, by continued and repeated cultivations in fresh blood Dr. Buchner also succeeded in changing a harmless Bacillus subtilis into an exceedingly malignant Bacillus anthracis, which, introduced into the organism of a healthy animal by inoculation, in every instance caused sure and speedy

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