CONTENTS OF No. 205.—New Series. 
MEMOIRS: 
Spirocheta (Trypanosoma) balbianii (Certes) and Spiro- 
cheta anodonte (Keysselitz): their Movements, Structure, and 
Affinities. By H. B. Fantuam, B.Sc.(Lond.), A.R.C.S., Derby 
Research Scholar and Assistant in the Zoological Department, 
University College, London; and St. Mary’s Hospital Medical 
School. (With Plates 1—3, and 11 Text-figures) 
The Structure and Life-History of Copromonas subtilis, nov. gen. 
et nov. spec.: a Contribution to our Knowledge of the Flagellata. 
By C. Cuirrorp Dosett, B.A., Scholar of Trinity College, Cam- 
bridge. (With Plates 4 and 5 and 3 Text-figures) ; 
Notes on Some Parasitic Protists. By C. Ciirrorp Dosett, B.A., 
Scholar of Trinity College, Cambridge. (With Plate 6) . 
Studies in Spicule Formation. VIII.—Some Observations on the 
Scleroblastic Development of Hexactinellid and other Siliceous 
Sponge Spicules. By W. Wooptanp, The Zoological Laboratory, 
King’s College, London. (With Plate 7) 
