CONTENTS. 



CONTENTS OF No. CXXI, N.S., APEIL, 1890. 



MEMOIRS : PAGE 



On Phymosoma variaus. By Akthur E. Shipley, M.A., 

 Fellow and Lecturer of Christ's College, Cambridge, and De- 

 monstrator of Comparative Anatomy in the University. (With 

 Plates I, II, III, and IV) 1 



The Spinning Apparatus of Geometric Spiders. By Cecil War- 

 burton, B.A., Christ's College, Cambridge. (With Plate V) . 29 



On the Structure and Functions of the Cerata or Dorsal Papillae in 

 some Nudibranchiate MoUusca. By W. A. Herdman, D.Sc, 

 F.L.S., Professor of Natural History in University College, 

 Liverpool. (With Plates VI, VII, VIII, IX, and X) . .41 



Further Observations on the Histology of Striped Muscle. By 

 C. F. Marshall, M.B., M.Sc, late Piatt Physiology Scholar 

 in the Owens College. (With Plate XI) . . . 



OnChsetobranchus, aNewGenusofOligochaetous Chsetopoda. 

 By Alfred Gibes Bourne, D.Sc.Lond., F.L.S., C.M.Z.S., Fellow 

 of University College, London, and of the Madras University. 

 (With Plate XII) 



The Presence of Ranvier's Constrictions in the Spinal Cord of 

 Vertebrates. By Dr. William Townsend Porter, of St. Louis. 

 (With Plate XII ^w) 



Professor Butschli's Experimental Imitation of Protoplasmic 

 Movement .....■• 99 



65 



83 



91 



