PROTOZOA 



By Marcus Hartog, M.A., Trinity College (D.Sc. 

 Lond.), Professor of Natural History in the Queen's 

 College, Cork 



POR1FERA (SPONGES) 



By Igerna B. J. Sollas, B.Sc. (Lond.), Lecturer on 

 Zoology at Newnham College, Cambridge 



COELENTERATA & CTENOPHORA 



By S. J. HlCKSON, M.A., F.R.S., formerly Fellow and 

 now Honorary Fellow of Downing College, Cambridge ; 

 Beyer Professor of Zoology in the Victoria. University of 

 Manchester 



ECHINODERMATA 



By E. W. MacBride, M.A., F.R.S., formerly Fellow of 

 St. John's College, Cambridge ; Professor of Zoology in 

 McGill University, Montreal 



BIOL. OEPT. 

 UNIV. TORONTO. 



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