4 
VOL. XV., No. 90. SE} AUGUST 1899. 
NATURAL 
SCIENCE 
A MONTHLY REVIEW OF 
SCIENTIFIC PROGRESS 



CONTENTS 
PAGE 
Nores AND COMMENTS . : : f . ; : 81 
Against the Tide—A Rare Rotifer—Does the Organism Repeat Itself ?— 
Nephrite—The Ordeal by Fire—American Species of Peripatus—Wearing of 
the Green—Brevis esse laboro, obscuris fio—The Parietal Eye—The Expan- 
sion of the Empire of Ribbed Toads—Degrees of Protective Adaptation—An 
Entomological Exhibition—At Last ?—Colours of Northern Monocotyledons 
—The Proper and Improper View of Heredity—Darwin’s Doggedness— 
Dispersal of Seeds—Reformed Nomenclature !—Science and Conduct. 
Some CONSIDERATIONS CONCERNING SYMMETRY . ‘ : ; 97 
By Professor R. J. Anderson. 
THE FLoRA OF THE ALPS f : : ‘ : ei LOS 
By Professor Alfred W. Bennett, M.A., B.Se., V.P.R.M.S. 
THe Score or NatuRAL SELECTION. 4 : ; ae ee 
By J. Lionel Tayler. 
Stray Impressions OF THE MARINE INVERTEBRATES OF SINGAPORE AND 
NEIGHBOURING ISLETS ; é ; : Meares te 
By F. P. Bedford, M.A. 
A THrEoRY OF SLEEP . E : : . , . 134 
By Professor A. L. Herrera. 
Fresh Facts .  — . : z : Ae 
Some New Books ; ’ : ; . : 3) RES 
OBITUARY wake 3 ¢ : 4 ; é5ie- PON 
Sir W. H. Flower, K.C.B. 
NEws . ; : : ; ; . : Sse FGA 


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