CONTENTS OF No. 149.—New Series. 
MEMOIRS : 
PAGE 
On the Variation of Haliclystus octoradiatus. By Epwarp T. 
Browne, B.A., University College, London. (With Plate 1) a 
The Collar-cells of Heterocceela. By Grorcn BippEer. (With 
Plate 2) : : f : : : 9 
The Metamorphosis of Echinoderms. By Henry Bury, M.A., F.L.S., 
late Fellow of Trinity College, Cambridge. (With Plates 3—9) 45 
A Criticism of the Cell-Theory ; being an Answer to Mr. Sedgwick’s 
Article on the Inadequacy of the Cellular Theory of Development. 
By Gitgert C. Bourne, M.A., F.L.S., Fellow of New. College, 
137 
Oxford : ‘ 4 : F : i F 
