PLATE XLI. 



Figs. 1-12. Machairopus idyoides, u. gen. and sp. 



Fig. 1. Female, seen from above. 



Fig. 2. Male seen from side; both magnified 50 diameters. 



Fig. 3. Anterior antenna of female. 



Fig. 4. Posterior antenna. 



Fig. 5. Mandible and palp. 



Fig. 6. Anterior foot-jaw. 



Fig. 7. Posterior foot-jaw. 



Fig. 8. Foot of first pair. 



Fig. 9. One of the following pairs of swimming feet. 



Fig. 1 0. Foot of fifth pair, female. 



Fig. 11. Abdomen of female. 



Fig. 1 2. Abdomen of male. 



Figs. 13-17. Zaus spinatus, Goodsir. 

 Fia;. 13. Female, magnified 50 diameters. 

 Fig. 14. Posterior antenna. 

 Fig. 15. Anterior foot-jaw. 

 Fig. 16. Posterior foot-jaw. 

 Fig. 17. Abdomen and tail. 



