Piate 1. 



Parasites and hosts. 



Ali figures naturai size. 



*S l 



Fig. 1. Low male of Inachus scorpio. Ventral view. 



Fig. 2. Female of Inachus scorpio. Ventral view. 



Fig. 3. Male of Inachus scorpio with a Sacculina neglecta on it. The abdomen and chelae of the host are 



intermediate in character between those of an ordinary male and female. Ventral view. 

 Fig. 4, Male of Inachus scorpio, carrying on its abdomen two specimens of Danalia curvata, and a small 



Sacculina neglecta (dark yellow). Ventral view. 

 Fig. 5. Male of Pachygrapsus marmoratus with Sacculina benedeni. The abdomen of host is intermediate 



between male and female in its dimensions. Ventral view. 

 Fig. 6. Female of JEriphia spinifrons with Sacculina eriphiae. The Sacculina assumes a purplish tinge owing 



to the brood of larvae being ready to hatch out. Ventral view. 

 Fig. 7. Callianassa subterranea with Parthenopea subterranea on its abdomen. The furrow shown on the 



parasite indicates the position of the mesentery. Viewed from left side. 

 Fig. 8. Eupagurus prideauxii with Peltogaster curvatus. The green colouring of the crab's abdomen is due 



to the roots of the parasite shining through. From left side. 

 Fig. 9. Eupagurus meticulosus with specimens of Peltogaster socialis on its abdomen. From left side. 



