CONTENTS OF No. 236.-New Series. 
MEMOIRS : 
PAGE 
The Development of E chinocardium cordatum. Parti. — The 
External Features of the Development. By E. W. MacBriDe, 
F.E.S., V.P.Z.S., Professor of Zoology in the Imperial College of 
Science and Technology. (With Plates 33 and 34) . . 471 
Chromosomes, Heredity and Sex : A Eeview of the Present State of 
the Evidence with regard to the Material Basis of Hereditary 
Transmission and Sex-Determination. By L. Doncaster, Sc.D., 
Fellow of King’s College, Cambridge. (With 4 Text-figures) . 487 
A ],Cytological Study of (Enothera mut. lata and (E. mut. 
semilata in relation to Mutation. By E. Euggles Gates, Ph.D., 
F.L.S., and Nesta Thomas, B.Sc. (With Plates 35-37 and 4 Text- 
figures) ....... 523 
On the Development and Morphology of the Mandibular and Hyoid 
Muscles of Mammals. By F. H. Edgeworth, M.D., Professor of 
Medicine, University of Bristol. (With Plates 38-45 and 9 Text- 
figures) ....... 573 
With Title, Contents, and Index to Vol. 59. 
