PLATE XL. 



Figs. 1-10. Oithona challengerii, n. sp. 



¥'m. 1. Female, seen from above: magnified 50 diameters. 



Fig. 2. Rostrum. 



Fig. 3. Posterior antenna. 



Fig. 4. Maxilla. 



Fig. 5. Anterior foot-jaw. 



Fig. 6. Posterior foot-jaw. 



Fig. 7. Foot of first pair. 



Fig. 8. Foot of fourth pair. 



Figs. 9, 10. Basal portions of the two setse of fifth foot. 



Figs. 11-15. Zaus spinatus, Goodsir. 

 Fig. 11. Anterior antenna. 

 Fig. 12. Mandible and palp. 

 Fig. 1 3. Foot of first pair. 

 Fig. 14. One of the swimming feet. 

 Fig. 15. Foot of fifth pair. 



