Febeuaby 7, 1896.] 



SCIENCE. 



211 



moteness, has been little explored geologically; 

 the present paper contains in part data obtained 

 by the author during five months in 1895. The 

 formations represented are divided into sedi- 

 mentary and igneous, the former of which in- 

 cludes two distinct classes : (1) a metamorphic 

 series, ranging in age from Cambrian through 

 the Triassic, and (2) the unaltered Tertiary and 

 Quaternary beds. The igneous rocks are gran- 

 itic and volcanic ; the former occur frequently 

 as intrusions in the metamorphic series, and 

 the latter consist of tuffs, liparites, andesites 

 and basalts. 



The Association of the Gasteropod Genus Cyclora 

 with Phosphate of Lime Deposits: By A. M. 

 MiLLEE. Several specimens of phosphate rock 

 examined showed numerous shells of Cyclora. 

 The analysis of the rocks as a whole gave vary- 

 ing percentages of P2O5 and Caj (P0j)2, while 

 analyses of the Cyclora casts showed them to 

 contain a much larger amount of these com- 

 pounds. In one case 89 per cent, of the ma- 

 terial of the casts was found to consist of these 

 compounds. 



The Buchanan Grravels : An Interglacial De- 

 posit in Buchanan County, Iowa: By Samuel 

 Calvin. These gravels in their typical ex- 

 posures form beds ten to fifteen feet in thickness, 

 lying above the Kansan drift and below the 

 lowan. The contrast between the hard unde- 

 cayed boulders of the lowan drift and the 

 decayed boulders of the Buchanan gravels and 

 Kansan drift is striking. These gravels are 

 made up of materials derived from the older 

 drift and were probably laid down in water im- 

 mediately behind the retreating edge of the 

 Kansan. 



Lacroix' Axial Goniometer: By N. H. WiN- 

 CHELL. This paper describes and figures a 

 comparatively simple apparatus for easily meas- 

 uring the optical angle of a mineral; it can be 

 adjusted to any microscope, being inserted in 

 the top of the body tube, and gives the optical 

 angle measured in air. 



Phenomena of Falling Meteorites: By O. C. 

 Fakrington. The author discusses the explo- 

 sions of meteorites and the sounds which ac- 

 company the fall of these bodies. Evidence is 

 given which shows that meteorites sometimes 

 do explode, producing marked detonations. 



Philadelphia Meeting of the Geological Society 

 of America : By Warren Upham. An account 

 of this meeting is given, together with abstracts 

 of all the papers presented and also abstracts, 

 of the discussions following the papers. 



Under ' Editorial Comment ' notice is made 

 of Prof. James Hall's gold medals, of the Trans- 

 vaal gold region, and of the geological map of 

 Europe prepared by the International Congress 

 of Geologists. Under ' Personal and Scientific- 

 News ' abstracts are given of geological papers 

 presented at recent meetings of various scientific 

 societies. 



SOCIETIES AND ACADEMIES. 



THE SCIENTIFIC ASSOCIATION OF THE JOHNS 

 HOPKINS UNIVERSITY, DECEMBER 19. 



One hundred and twenty -third regular meet- 

 ing, December 19, 1895. President Kemsen in 

 the chair. 



The following papers were presented and 

 read : 



1. Theories of Color Sensation and of the Percep- 

 tion of Sound: By W. J. Mather. 



Mr. Mather gave a brief review of the older 

 theories of color perception, followed by a care- 

 ful discussion of the present state of our knowl- 

 edge of this suject. He dwelt especially upon 

 the theories of Mrs. Franklin. 



2. Recent Work on Impregnation in Floivering 

 Plants : By J. E. Humphrey. 



Mr. Humphrey showed that until about four 

 years ago impregnation in flowering plants was 

 known to take place only by the growth of the 

 pollen tube across the cavity of the ovary and 

 through the micropyle left by the coats of the 

 ovule. In 1891 Treub described impregnation 

 in Casuarina, the Australian iron-wood, by the 

 downward growth of the pollen-tube through 

 the tissue of the ovary to the chalaza, or stalk 

 of the ovule, and its upward growth through, 

 the body of the ovule to the egg-cell. In 1894 

 Miss Benson found the same thing to occur in 

 several English catkin-bearing plants, the horn- 

 beam, the alder, the hazel, etc. 



Nawaschin has just published the results of 

 his studies of the white birch, which agrees- 

 closely with the alder. In attempting to ex- 



