L.M.B.C. MEMOIRS 



No. XVI. CANCER. 



JOSEPH PEARSON, M.Sc, 



Demonstrator in Zoology, University of Liverpool. 



CONTENTS. 



PAGE 



Introduction 2 



External Characters ... 6 



Appendages 22 



Endophragmal System . . 31 



Structure of Integument . 45 



Ecdysis 53 



Autotomy 56 



Muscular System .... 



Coelom and Body Cavity 



Alimentary Canal : — 



General Description and 

 Histology . 



Digestive Gland . 



Ossicles of Fore-gut 



Muscles of Pore-out 



65 



84 



85 



92 



97 



103 



PAGE 



Blood Vascular System . . \ 10 

 Respiratory System . . . 126 

 Excretory System .... 136 

 Nervous System .... 149 



Sense Organs 156 



Reproductive System . . .163 



Development 169 



Economics and Bionomics : — 



General Habits .... 173 

 ' The Crab Fisheries . . .177 



Size of Crabs at Maturity 177 



Distribution and 



Migration 179 



Bionomics of Ecdysis . . 183 



Description of Plates . . . 195 



