Proc. R I. Acad. Vol. XXIY, Section B. 



Araneida. 



Pedipalpi. 

 Scorpionida. 



Chemetida.. 



Phalangida. 

 Acarinida. 



Xlpliosura. 



Pycnogonida 



Suggested Kelali on ships between the Arthropod Classes and 

 their principal Orders. 



