PLATE XX. 



Figs. 1-11. Arcturus spinosus. 

 Fig. 1. Male, dorsal aspect. 

 Fig. 2. Male, lateral aspect. 

 Fig. 3. Female, dorsal aspect. 

 Fig. 4. Female, lateral aspect. 



Fig. 5. One of the posterior thoracic limbs of female. 

 Fig. 6. One of the posterior thoracic limbs of male. 

 Fig. 7. One of the anterior thoracic appendages of female. 

 Fig. 8. One of the anterior thoracic appendages of male. 

 Fig. 9. Antennule. 

 Fig. 10. Basal joints of antenna. 

 Fig. 11. Portion of flagellum of antennule ; more highly magnified 



Fig. 12. Arcturus baffini. 

 Fig. 12. Basal joints of antenna, 



