CONTENTS OF No. 227.-New Series. 
MEMOIRS : 
PAGE 
On the Condition of the Epidermal Fibrils in Epithelioma. By 
George Arnold, M.Sc., from the Cancer Research Laboratory, 
University of Liverpool. (With Plate 25 and 1 Text-figure) . 283 
Note on the Mechanism of Discharge of the Cuvierian Organs of 
Holothuria nigra. By George Ralph Mines, M.A., Fellow 
of Sidney Sussex College, Cambridge (from the Laboratory of the 
Marine Biological Association, Plymouth). (With Plate 26) . 301 
On the Histological Structure of the Retina of the Lateral Eyes of 
Sphenodon punctatus, with Special Reference to the Sense- 
cells. By Freda Bage, M. Sc. (Melbourne), F.L.S. (from the 
Zoological Department, King’s College, University of London). 
(With Plates 27-29) ..... 305 
The Problem of Sex Determination in Dinophilus gyrociliatus. 
Part 1. — The Sexual Cycle. By Cresswell Shearer, M.A., Clare 
College, Cambridge. (With Plates 30-34 and 5 Text-figures) . 329 
