OCTOBEB 28, 1904.] 



SCIENCE. 



565 



SCIENTIFIC JOURNALS AND ARTICLES. 

 The Botanical Gazette, for October, con- 

 tains the following articles : Bradley M. Davis 

 has discussed the relationships of sexual or- 

 gans in plants, presenting their classification 

 based upon certain evolutionary principles 

 and also suggesting a terminology that is 

 more precise. — Bruce Fink has contributed 

 another paper upon the ' ecology ' of a lichen 

 society, this time considering a curiously iso- 

 lated society upon a sandstone riprap in lov^a. 

 — J. T. Bergen has given some results of his 

 observations in Italy on the transpiration of 

 sun leaves and shade leaves of the olive and 

 other broad-leaved forms, shovcing in general 

 that xerophytic leaf structure is not always in- 

 compatible with abundant transpiration. — A. 

 S. Hitchcock, in his fourth paper, entitled 

 ' Notes on North American Grasses,' discusses 

 Poa serotina Ehrh. and P. flava L., and also 

 the genus Digitaria Heist. — F. L. Stevens has 

 made a further contribution to our knowledge 

 of oogenesis and fertilization in the genus 

 Albugo by presenting his results with A. 

 Ipomoeae-Pandiiranae. 



The September issue of the journal of Ter- 

 resirial Magnetism and Atmospheric Electric- 

 ity has as its frontispiece the portrait of 

 Alexander von Humboldt, and contains be- 

 sides notes and abstracts and titles of recent 

 publications, the following articles : 



N. Umow : ' Die Construction des Geometrischen 

 Bildes des Gauss'schen Potentials, als Methode 

 zur Erforschung der Gesetze des Erdmagnetismus.' 



L. A. Bauek : ' The Physical Decomposition of 

 the Earth's Permanent Magnetic Field, No. IV.' 

 a. Introductory Note; b. Secular Motion of a Free 

 Magnetic Needle; c. Vertical Earth-Air Electric 

 Currents; d. Residual Magnetic Field and Diurnal 

 Variation Field. 



L. A. Bauer: 'Appeal for Cooperation in Mag- 

 netic and Allied Observations during the Total 

 Solar Eclipse of August 29-30, 1905.' 



W. VAN Bemmei-ek : ' Magnetic Survey of the 

 Dutch East Indies.' {Second Communication.) 



J. DE MoiDREY : ' Note sur I'Amplitude de 

 I'Oscillation diurne de la Declinaison Magnfitique 

 et son Inggalite Annuelle.' 



G. W. LiTTLEHALES : 'Magnetic Declinations by 

 Peary in the Arctic E,egions, 1900--02.' 



W. F. Wallis : ' Principal Magnetic Disturb- 

 ances recorded at Cheltenham Magnetic Observa- 

 tory, May 1-August 31, 1904.' 



DISCUSSION AND CORRESPONDENCE. 



THE STOMACH STONES OF THE PLESIOSAURS. , 



Apropos of Dr. Eastman's letter on the 

 ' stomach stones ' of the plesiosaurs, published 

 in Science^ No. 510, p. 465, permit me to state 

 that there is not a shadow of doubt that the 

 plesiosaurs, both Cretaceous and Jurassic, 

 had the habit of swallowing such stones. At 

 least thirty instances are now known of the 

 occurrence of the very peculiarly worn pebbles 

 between the ribs or with the remains of 

 plesiosaurs in both Europe and America. The 

 fact was first published by Professor Seeley, 

 of England, in 1877, and Seeley it was who 

 first suggested their use in digestion and the 

 possession of a ' gizzard ' by these animals. 

 This absolves Mr. Brown. Crocodiles are fre- 

 quently reported to have like habits, and 

 Buckland says that the Arabs determine the 

 age of these animals by the number of the 

 stones found in the stomach, one being swal- 

 lowed each year ! Similar pebbles have also 

 been found with the remains of extinct croco- 

 diles, and St. Hilaire gives a minute account 

 of such instances. I need not say also that 

 there are various accounts in the literature of 

 like habits possessed by some of the seals and 

 sea-lions. I doubt not that the habit was an 

 intentional one with the plesiosaurs, nor do I 

 thinli that Dr. Eastman would doubt either, 

 had he ever collected the remains of these 

 animals in the field. That the plesiosaurs 

 had a gizzard-like stomach I do not believe, 

 but I see nothing startling in the suggestion — 

 with due apologies to Dr. Eastman. His argu- 

 ment, that, if the plesiosaurs were of lith- 

 ophagous proclivities, other reptiles should 

 be expected to gorge themselves on a like min- 

 eralogical diet is hardly pertinent. The 

 prairie chicken has the regulation gallinaceous 

 gizzard, and, therefore, the sage hen should 

 have one. But it has not. Ai uno disce 

 omnes is not always safe. And, it must be 

 remembered, all reptiles have stomachs with 

 thick muscular walls. 



S. W. WlLLISTON. 



