470 



NA TURE 



[Sept. 27, 1877 



Among papers in Section B (Geology, Zoology, Botany, and 

 Anthropology! we notice the following as likely to prove of im- 

 portance : — 7/ie Strticlure of Eruptive Ahwii/aiiis, by Prof. 

 Powell ; On Sex in Fltnutis, by Mr. Thos. Meehan ; On the 

 0) i^iiiai Conntction of thf Eas/ern and IVes/ern Coalfields of the 

 Ohio Vallty, On the Continuation of the Fields of the Alleghany 

 Chain to the North of the Delaware River, and On the Geogra- 

 phical and Geological Distribution of the Genus Bcatricea, and 

 of certain other Fossil Corals in the Rocks of the Cincimiati 

 Group, all by Prof. Shaler ; On the Classification of the Extinct 

 Fishes of the Lower Types, and On the Origin of Structural 

 Variation, by Prof. Cope ; A'otes on the Geology of the Rochy 

 Mountains, by Prof. Sterry Hunt ; Some Po/ular Errors con- 

 cerning the North American Indians, by Capl. Powell. In a 

 paper by tlie same autlior. On Overplacement, he asserted that 

 the effects of glacial action had been greatly over-estimated in 

 the western country, and that the " overplacement " in the 

 Mississippi Valley was due rather to the erosion of ihe atmo- 

 sphere, the rams of centuries, and the river.-. A curious paper in 

 this section was by a lady, Mrs. H. K. Ingram, On Atmospheric 

 Concussion as a Means of Disinjection, in which she confidently 

 advanced the idea, b.ised on the germ-theory of disease, that 

 by means of concussion produced by gunpowder explosion or 

 other effective method, cholera and other epidemic diseases could 

 be effectually prevented or dissipated. In a paper by Lieut.-Col. 

 Mallery, the author held that the Indians are not passing away ; 

 there are now in existence, he stated, 300,000 Indians, of 

 whom 50,000 are Sijux. Instead of decreasing with advancing 

 civiUsation, they are steadily increasing, and Col. Mallery be- 

 lieves that the native population of America, north of Mexico, at 

 the time of its discovery, has been widely over-estimated. Capt. 

 Powell agreed wiih Col. Mallery, and stated his conviction that 

 at the time of the discovery of America there were not more than 

 500,000 natives north of Mexico, while now in the States, 

 Canada, and Alaska there are about 400,000. As president of 

 the Sub-section of Anthropology, Prof. Daniel Wdson gave an 

 interesting address on Races in America, presenting a resume oi 

 the various theories that had tieen advanced with respect to 

 Americiin ethnology and the peopling of America, and giving 

 some wise advice as to how future researches ought to be con- 

 ducted. Another anthropological paper was on the Ong-in of 

 the Japanese, by a native of Tokio, Shuje I^awa, in which the 

 author came to the conclusion that the present Japanese are 

 descended from Hindoo conquerors. 



No paper of general importance seems to have been read in 

 permanent Su^-section C (Chemistry), all of them, judging from 

 the titles, being on points mainly of manufacturing interest. 



It was decided that the next meeting should be held at St. 

 Louis, and at the closing meeting an Education Committee was 

 appointed with a view to the introduction of science into the 

 schools of the country. Another committee was appointed to 

 report annually on the relations of science to the industrial arts, 

 and the following important resolution was passed in reference 

 to the Signal .Service Weather Reports : — 



"Resolved, that this Association most respectfully asks the 

 attention of Congress and the country to the great advances in 

 the science of meteorology and in the art of weather prediction, 

 which might be hoped for if the meteorological observations now 

 taken by the Army Signal Office, under the direction of the 

 Secretary of War, were made the subject of special research and 

 discussion by scientific experts. 



"Resolved, further, that a committee of five members or 

 fellows be appointed by the President to represent this Associa- 

 tion before Congress as petitioners for such permanent and 

 liberal organisation of the meteorological service, that the 

 valuable material collected by it may be utilised in the manner 

 here suggested." 



INTRODUCTION AND SUCCESSION OF 

 VERTEBRATE LIFE IN AMERICA ' 



'T^HE reptiles most characteristic of our American cretaceous 

 -'■ strata are the Mosasauria, a group with very few repre- 

 sentatives in other parts of the world. In our cretaceous seas 



^ Abstract of a lecture delivered at the Nashville meeting of the American 

 , August 30, by Prof O. C. Marsh Continued from p. 450. 



they ruled supreme, as their numbers, size, and carnivorous 

 habits enabled them to easily vanquish all rivals. Some were 

 at least sixty feet in length, and the smallest ten or twelve. In 

 the inland cretaceous sea, from which the Rocky Mountains 

 were beginning to emerge, these ancient "sea serpents" 

 abounded ; and many vvei-e entombed in its muddy bottom. On 

 one occasion, as I rode through a valley washed out of this old 

 ocean bed, I saw no less than seven different skeletons of these 

 monsters in sight at once. The mosasaurs were essentially 

 swimming lizards, with four well-develnped paddles, and they 

 had little affinity with modern serpents, to which they have been 

 compared. 



The Crocodilia are abundant in rocks of cretaceous age in 

 America, and two distinct types are represented. The tertiary 

 marine beds of the Atlantic coast contain comparatively few 

 crocodilian remains, and all are of modern types, the genus 

 Guvialis having one eocene species, and the alligator being 

 represented only in the latest deposits. 



It is worthy of special mention in this connection that no true 

 Lacertilia, or lizards, and no Ophidia, or serpents, have yet been 

 detectrd in .•\merican cretaceous beds ; although their remains, 

 if present, would hardly have escaped observation in the regions 

 explored. The former v.ill doubtless be found, as several species 

 occur in the mesozoic of Europe, and perhaps the latter, 

 although the 0|)hidians are apparently a more modern type. In 

 the eocene lake-basins of Western America, remains of lizards 

 are very numerous, and indicate species much larger than any 

 existing to-day. 



The first American serpents, so far as now known, appear in 

 the eocene, which contains also the oldest European species. 



The Ptirosauria, or flying lizards, are among the most inter- 

 esting reptiles of mesozoic time, and many of them left their 

 remains in the soft sediments of our inland cretaceous sea. 

 These were veritable dragons, hiving a .spread of wings of from 

 ten to twenty-five feet. 



The strange reptiles known as Dinosauria, which, as we have 

 seen, were numerous during the deposition of our triassic shales 

 and sandstones, have not yet been found in .'Vmerican Jurassic, 

 but were well represented here throughout the cretaceous, and at 

 its close became extinct. These animals pos-ess a peculiar 

 interest to the anatomist, since, although reptilian in all their 

 main characters, they show clear affinities with the birds, and 

 have some features which may point to mammals. The cre- 

 taceous dinosaurs were all of large size, and most of them walked 

 on the hind feet alone, like modem struthious biids. Near the 

 base of our cretaceous formation in beds which I regard as the 

 equivalent of the European Wealden, the most giganic forms of 

 this Older yet discovered have recently been brought to light 

 One of these monsters (Titanosaurus tnontanus) from Colorado, 

 is by far the largest land animal yet discovered, its dimensions 

 being greater than was supposed possible in an an.mal that 

 lived and moved upon the land. It was some fifty or sixty feet 

 in length, and, when erect, at least thirty feet in height. It 

 doubtless fed upon the foliage of the mountain forests, portions 

 of which are preserved with its remains. With Titanosaurus 

 the bones of smaller dinosaurs, one (Nanosaurus) not larger th n 

 a cat, as well as those of crocodiles and turtles, are not uncom- 

 mon. The recent discovery of these interesting remains, many 

 and various, in strata that had long been pronounced by pro- 

 fessional explorers barren of vertebrate fossils, should teach 

 caution to those who decline to accept the imperfection of our 

 knowledge to-day as a fair plea for the supposed absence of 

 intermediate forms. 



In the marine cretaceous beds of the west only a single 

 dinosaur [f/adrosautus a^ilii) has been found, but in the higher 

 fresh-water beds which mark the close of this formation their 

 remains are numerous, and indicate several w'ell-marked species, 

 if not genera. 



The first appearance of birds in America, according to our 

 present knowledge, was during the cretaceous period, although 

 many announcements have been made of their existence in pre- 

 ceding epochs. The evidence of their presence in the trias, 

 based on footprints and other impressions is at present, as we 

 have seen, without value, although we may confidently await 

 their discoveiy there if not in older formations. Archiropteryx, 

 from the European Jura, the oldest bird known, and now for- 

 tunately represented by more than a single specimen, clearly 

 indicates a much higher antiquity for the class. The earliest 

 American forms at present known are the Odontorndhcs, or birds 

 with teeth, which have been exhumed within the last few years 



