CONTENTS 
OF  VOL.  148. 
I.  The  Bakeeian  Lectuee. — On  the  Stratifications  and  Bark  Band  in  Electrical  Dis- 
charges as  observed  in  Torricellian  Vacua.  John  P.  Gassiot,  F.P.-R. -(S',  page  1 
II.  A Memoir  on  the  Theory  of  Matrices.  Aethue  Cayley,  P.P. -S'.  . . 17 
III.  A Memoir  on  the  Automorifiiic  Linear  Transformation  of  a Bipartite  Quadric 
Function.  By  Aethue  Cayley,  Esq.,  F.R.S 39 
IV.  Supplementary  Researches  on  the  Partition  of  Numbers.  By  Aethue  Cayley,  Esq., 
F.R.S 47 
V.  An  Account  of  some  recent  Researches  near  Cairo,  undertaken  with  the  view  of 
throwing  light  upon  the  Geological  History  of  the  Alluvial  Land  of  Egypt. — 
Instituted  by  Leonaed  Hoenee,  Esq.,  Vice-President  of  the  Royal  Society,  Fellow 
of  the  Royal  Society  of  Edinburgh,  and  Vice-President  of  the  Geological  Society.  53 
VI.  Researches  on  the  Structure  and  Homology  of  the  Reproductive  Organs  of  the  Annelids. 
By  Thomas  Williams,  M.D.,  F.R.S.,  Physician  to  the  Swansea  Infirmary.  Com- 
municated by  Thomas  Bell,  Esq.,  F.R.S.,  President  of  the  Linnean  Society,  &c.  93 
VII.  On  the  PaHitions  of  the  B-Pyramid,  being  the  first  class  of  B-gonous  N-edra. 
By  the  Rev.  Thomas  P.  Kiekman,  M.A.,  F.R.S.,  Rector  of  Croft  with  South- 
worth  145 
VIII.  On  the  Isolation  of  the  Radical,  Mey'curic  Methyl.  By  Geoege  Bowdlee  Buckton, 
Esq.,  F.R.S 163 
IX.  Description  of  the  Skull  and  Teeth  of  the  Placodus  laticeps,  Owen,  with  indications 
of  other  new  Species  of  B\q.co(\.us,,  and  evidence  of  the  Saurian  Nature  of  that  Genus. 
By  Professor  Owen,  V.P.R.S.,  Superintendent  of  the  Natural  History  Departments 
in  the  British  Museum 169 
X.  On  the  Properties  of  Electro-deposited  Antimony.  By  G.  Goee,  Esq.  Communicated 
by  Dr.  Tyndall,  F.R.S 185 
XI.  On  the  Constitution  of  the  Essential  Oil  of  Rue.  By  C.  Geeville  Williams,  Lec- 
turer on  Chemistry  in  the  Normal  College,  Swansea 199 
