Proceedings and List of Papers read. 25 



diastase than the distal. This cannot be the true explanation, since 

 we find that the pre-existent enzymes of the endosperm practically 

 play no part in the self-depletion. 



DESCRIPTION OF PLATE 1. 



FlG. 1. Examples of " sub-scutellar " starch- erosion, showing incipient and 

 advanced forms. Two granules, the one in the centre of the field, the 

 other on the right, show incipient " sub-aleuronic " erosion. 



FIG. 2. Examples of " sub-aleuronic " starch-erosion in incipient stages. 



FIG. 3. Examples of "sub-aleuronic" starch-erosion in more advanced stages. 



(For the production of these photographs we are indebted to Mr. Albert Norman.) 



March 10, 1898. 



Sir JOHN EVANS, K.C.B., D.C.L., LL.D., Treasurer, in the Chair. 

 The following Papers were read : 



I. " On the Rotation of Plane of Polarisation of Electric Waves by 

 a Twisted Structure." By Professor J. C. BOSE. Commu- 

 nicated by LORD RAYLEIGH, F.R.S. 



II. " On the Production of a " Dark Cross " in the Field of Electro- 

 magnetic Radiation." By Professor J. C. BOSE. Communi- 

 cated by LORD RAYLEIGH, F.R.S. 



III. "An Extension of Maxwell's Electro-magnetic Theory of Light 



to include Dispersion, Metallic Reflection, and allied Pheno- 

 mena." By EDWIN EUSER, A.R.C.S. Communicated by 

 Captain ABNEY, F.R.S. 



IV. " On the Relative Retardation between the Components of a 



Stream of Light produced by the Passage of the Stream 

 through a Crystalline Plate cut in any Direction with 

 respect to the Faces of the Crystal." By JAMES WALKER, 

 M.A. Communicated by Professor CLIFTON, F.R.S. 



V. " On the Relation between the Diurnal Range of Magnetic 

 Declination and Horizontal Force and the Period of Solar 

 Spot Frequency." By W. ELLIS, F.R.S. 



VOL. LXIII. 



