iv CONTENTS. 



PAGE 



On the Causes which lead to the Attachment of the Mammalian 

 Embryo to the Walls of the Uterus. By Richard Assheton, 

 M.A. (With Plate 19) 173 



The Primitive Streak of the Rabbit ; the Causes which may deter- 

 mine its Shape, and the Part of the Embryo formed by its 

 Activity. By Richard Asshexon, M.A. (With Plates 20—22) 191 



On the Growth in Length of the Prog Embryo. By Richard 

 Assheton, M.A. (With Plates 23 and 24) . . . 223 



CONTENTS OF No. 147, N.S., MARCH, 1895. 



MEMOIRS : 



On the Variation of the Tentaculocysts ofAureliaaurita. By 

 Edward T. Browne, B.A., University College, London. (With 

 Plate 25) 245 



On the Structure of Vermiculus pilosus. ByE. S. Goodrich, 

 F.L.S., Assistant to the Linacre Professor, Oxford. (With 

 Plates 26— 28) 253 



On the Mouth-parts of the Cypris-stage of Balanus. By Theo. 

 T. Groom, F.Z.S., late Scholar of St. John's College, Cam- 

 bridge. (With Plate 29) 269 



A Study of Coccidia met with in Mice. By J. Jackson Clarke, 

 M.B. Lond. (With Plate 30) 277 



Observations on Various Sporozoa. By J. Jackson Clarke, 

 M.B.Lond. (With Plates 31— 33) . . . .287 



A Revision of the Genera and Species of the Branchiostomidse. 

 By J. W. Kirkaldy. (With Plates 34 and 35) . . 303 



Sedgwick's Theory of the Embryonic Phase of Ontogeny as an Aid 

 to Phylogenetic Theory. By E. W. MacBride, B.A., Fellow 

 of St. John's College, Cambridge ; Demonstrator in Animal 

 Morphology to the University of Cambridge . . . 325 



