CONTENTS. 



CONTENTS OF No. LXXIII, N.S., JANUARY, 1879. 

 MEMOIRS : 



PAGE 



On the Existence of a Head-Kidney in the Embryo Chick, and on 

 Certain Points in the Development of the Miillerian Duct. By 

 E. M. Balfoub, M.A., Eellow of Trinity College, Cambridge ; 

 and Adam Sedgwick, B.A., Scholar of Trinity College, Cam- 

 bridge. (With Plates I and II) . . . .1 



Notes on some of the Reticularian Rhizopoda of the "Challenger " 

 Expedition. By Heney B. Beady, E.R.S. (With Plates 

 III, IV, and V) 20 



Researches on the Flagellate Infusoria and Allied Organisms. By 

 0. BuTscHLi, Professor of Zoology in the University of Heidel- 

 berg. (With Plate VI) . " . . . .63 



The Morphology and Systematic Position of the Spongida. By 

 E. M. Balpoue, M.A., Eellow of Trinity College, Cambridge 103 



• Flagellated Organisms in the Blood of Healthy Rats. By Timothy 



Richards Lewis, M.B. ..... 109 



NOTES AND MEMORANDA : 



Observation on the Capitellid^ by Dr. Hugo Eisig . . 115 



Bacteria as the Cause of the Ropy change of Beet-root Sugar . 116 



Stein's ' Organismus der Infusionsthiere ' . . . 118 



PROCEEDINGS OF SOCIETIES: 



Dublin Microscopical Club ..... 120 



Title, Contents, and Index to Vol. XVIII. 



b 



