1548 



CRUSTACEA. 



The preceding table affords the following lists of genera of the three 

 grand divisions, according to the present state of the science. 



1. GENERA EXCLUSIVELY AMERICAN OR OCCIDENTAL. 



2. GENERA EXCLUSIVELY OF THE AFRICO-EUROPEAN DIVISION. 



1. Maioidea. 



Lissa. 



Stenorhynchus. 

 Amathia. 

 Eurynome. 



2. Cancroidea. 



Perimela. 



Portumnus. 



Polybius. 



3. Grapsoidea. 



Gonoplax. 

 Heterograpsus. 

 Brachynotus. 

 Hymenosoma. 



4. Leucosoidea. 



Ilia. 



5. Corystoidea. 



This. 



