6oo 



NA TURE 



{Oct. 1 6, i! 



The most interesting discussion was on educational methods 

 in laboratories and chemical lectures, by Prof. Remsen, who 

 remarked that in Germany the student does not go into the 

 laboratory until he understands reactions, while in England and 

 the United States he is placed there at the beginning of the 

 course. Prof. Remsen follows an order of instruction in which 

 the student becomes first acquainted with apparatus and methods 

 •of manipulation. He next makes gases, and repeats lecture 

 experiments. He then experiments on oxidation and reduction. 

 Next follows the quantitative analysis of air. Then come alkali- 

 metry and acidimetry, with success. This practical work and 

 the lectures occur simultaneously, and by the time the lecturer 

 has reached the metallic elements, the students are ready to take 

 up test-tube reactions with profit. During the first year the 

 student should only just begin analysis. After the general pro- 

 perties of the metals are known, let the student devise methods 

 o! separation. The course of instruction in our colleges Prof. 

 Remsen regards as too short and superficial. Lecture-experi- 

 ments should never be made for show. ^Esthetics and chemistry 

 are entirely distinct. 



Prof. Atwater said that chemistry is taught now, as a rule, 

 after the student has acquired the methods of the classics and 

 has never been taught to observe facts. Chemists must show 

 that their science will give what is called "liberal culture," or 

 it will not find a place in our educational institutions. Present 

 methods are not doing this, as they fail to make the student 

 tbink for himself. 



In the Section of Geology and Geography no paper was 

 greeted with more interest or closer attention than that by Prof. 

 J. E. Hilgard, Director of the U.S. Coast Survey, on the rela- 

 tive level of the Gulf of Mexico and the Atlantic Ocean, with 

 remarks on the Gulf Stream and deep-sea temperatures. Its two 

 most essential points are : — (i) The discovery by a most careful 

 ■series of levels, run from Sandy Hook and the mouth of the 

 Mississippi Kiver to St. Louis, that the Atlantic Ocean at the 

 former point is 40 inches lower than the Gulf of Mexico at the 

 latter point ; and (2) that ocean-water at all depths exceeding 

 1000 fathoms possesses a temperature of nearly 35 F., because 

 this is the temperature consistent with its greatest density. 

 Should tlie water become either cooler or warmer, it must ex- 

 pand ; which it cannot do on account of the superincumbent 

 pressure. 



Prof Henry S. Williams, of Cornell University, in a 

 paper on the influence of geographical and physical con- 

 ditions in modifying fossil faunas, introduced the exceed- 

 ingly important subject of the extent to which palteonto- 

 logical evidence is to be regarded as an absolute guide 

 in correlating strata in different regions. Prof. Williams ex- 

 plained a series of sections, principally in Chemung and Catskill 

 rocks, ta! en from a number of localities across New York State, 

 and adduced from them abundance of proof that faunas in 

 Devonian times, as at present, changed not only geologically in 

 sequence of time, but also geographically according to the areas 

 of their distribution. The influences which 1 in night about a 

 change in the character of the sediment deposited also mani- 

 fested themselves in altering the forms of the organisms in- 

 habiting these sediments. 



Prof. Alexis Julien of New York communicated the results of 

 a very extended study of the Eowon canadense from nearly all 

 the localities where it has thus far been found, adding other 

 localities of his own discovery. The result of his investigations 

 led him to decide in favour of the inorganic nature of the so- 

 called fossil, although his ideas in regard to the mode of its for- 

 mation differ considerably from any heretofore advanced. He 

 noticed as universal in all localities, that the calcium and mag 

 nesium carbonates were very unequally distributed in the Eozoonal 

 limestones, and that there was a large development of pyroxene 

 where the dolomite was least abundant. He moreover observed 

 the constant tendency on the part of pyroxene to be arranged in 

 layers alternating with either calcite or apatite, as well as 

 abundant evidence that pyroxene passed by hydration into 

 serpentine, a process which could be seen in every stage at any 

 of the localities visited. From these data it was assumed that 

 siliceous waters, permeating limestones originally evenly dolo- 

 mitic, would cause the local development of pyroxene by the 

 change of the magnesium carbonate into the corresponding 

 silicate. Were it the case, as so often occurs, that this pyroxene 

 was developed in layers, its subsequent alteration to serpentine 

 or loganite would readily account for all the appearances exhi- 



bited by the Eozoon, without the necessity of appealing to organic 

 agencies. 



A large number of papers (forty-three in all) were presented 

 before the Section of Biology ; but we regret that in our limited 

 space we can give merely the briefest outlines. The first we 

 may mention was a paper by Mr. D. C. Beyer, on the influence 

 of oxygenated and unoxygenated blood, as well as of blood in 

 various degrees of dilution, on the heart of the frog and terrapin. 

 The paper aimed to prove that it is not concentrated mammalian 

 blood which produces the greatest amount of work either in the 

 heart of the frog or that of the terrapin, but that a certain degree 

 of dilution is necessary. 



Dr. C. S. Minot read a paper on biological problems. The 

 author opposed the trinomial system, and considered the present 

 mode of determining species entirely unscientific, and thought 

 that the species should be based on a statistical study of all the 

 variations that are known to occur. Individuals are not always 

 homologous. The only fixed units are (1) cells ; (2) the whole 

 series of generations of cells from a single ovum — a cell- cycle. 

 An individual may be almost any fractional part of a cell-cycle. 

 Roughly speaking, the higher the organism the fewer the 

 number of individuals it comprises. The author considered the 

 ovum to be homologous with the encysted protozoon, the radial 

 zone being equivalent to the capsule or cyst of the protozoon, 

 and the contents also homologous. 



Prof. E. D. Cope in a paper on the phyllogeny of the Artio- 

 dactyle mammals derived from American fossils, considered the 

 derivation of the selenodont dentition from the bunodont as 

 established from a mechanical point of view. The oldest Ame- 

 rican Artiodactyl (Pantolestes) is bunodont. The modification 

 proceeded as in other ruminants on the lines of the co-ossification 

 of the bones of the legs and feet. The peculiar structure of the 

 carpus in the Oreodontidre shows them to be, without doubt, 

 the ancestors of the Tragulina. The following table represents 

 the present views of the author on the subject : — 



Tritubercular bunodontia (Pantolestidae). 

 I 



Selenodontia. 



1 



Quadritubercular bunodontia. 



Hyopotamidte. Oreoilonddiie. Poebrotheriidi~e. 



1 1 



(?) Pecora. Tragulina. Tvlopoda. 



Mr. H. F. Osborne presented observations on the amphibian 

 brain, containing results of microscopic study upon the frog, 

 Menobranchus, Menopoma, and Amphiuma. His method of 

 study was by making series of sections, in their different planes. 

 The relative position of gray and white matter was the same as 

 that found in the spinal cord of these and other vertebrates. 

 The courses of the principal nerve-fibres in their course from the 

 medulla forward to the hemispheres was described, showing the 

 course of the transverse commissures, and pointing out a com- 

 missure in the roof of the third ventricle hitherto overlooked. 

 This demonstrated that each brain-segment had its own dorsal 

 commissure. The differences of the cerebellum in the Anura 

 and Urodela were pointed out, and the resemblances of the 

 latter to the mammalian brain were dwelt upon. The pia blood- 

 vessels are all sent in upon the anterior face of the pituitary 

 body. The pineal elements were shown to consist of certain 

 very inconspicuous foldings of the epithelium of the roof of the 

 third ventricle, which have been generally overlooked. These 

 foldings represent what remains of the stalk of the pineal gland. 



Mr. S. Garman's paper on Chlamydoselachus, the frilled 

 shark, treated of the internal anatomy of this peculiar shark. 

 The nearest forms are Notanidte, Hexanchus, and Heptanchus. 

 Hind and fore brain resemble that of fcetal sharks ; the cartilage 

 is soft : the lateral line is open as in fretal sharks, and continued 

 to the end of the tail. The pelvis is twice as long as broad : the 

 nearest resemblance to this is seen in the fretal Heptanchus. 

 According to the author, the Chlamydoselachus may be a sub 

 order of the Galei. 



The next paper was by Prof. E. D. Cope, on the mammalian 

 affinities of Saurians of the Permian epoch, and referred to the 

 detection of mammalian resemblances between Thesomorphus 

 and reptiles of the Permian epoch. Resemblances in the pelvic 

 and scapular arch were pointed out. The quadrate bone was 

 discussed, referring to the theory of Albrecht. The genus 



