224 SPOLIA ZEYLANIOA. 



The proportional lengths of the various joints are as 

 follows : — 



Segments: 1. 2-4. 5. 6. 7. 8-9. 10. 11. 12. 13: 

 43 43 14 17 28 37 23 26 37 63 



Segments: 14: 15. 16. 17. 18. 19. 20. 21. 22. 23. 24-25. 

 68 68 77 86 88 77 51 46 31 34 43 



The Fifth Pair of Legs. — Both rami are three-jointed. 



Exopod 1 bears a marginal spine, but has no internal seta ; 

 exopod 2, in addition to the single external marginal spine, 

 bears the usual spine on its inner border. This spine is long 

 and has a somewhat swollen base ; it tapers gradually to a fine 

 point and bears no teeth on its surface. Exopod 3 has two 

 marginal spines and a finely serrated end-spine. 



The endopodite reaches to the level of the joint between 

 exopods 2 and 3. Endopod 1 presents a well-marked rounded 

 swelHng at its distal external angle. 



The remaining appendages appear to be very similar to 

 those of Centropages alcocki (Sewell, 1912, p. 338, PL XVII., 

 figs. 1-7), but the serrations on the terminal spines of the 

 swimming feet are not so coarse and are less widely separated . 



Genus PseudodiaptomuS, Herrick. 



PSEUDODIAPTOMUS AURIVILLII, Clcve. 



PseudodiaptomuS aurivillii, Cleve, 1901, p. 48. PI. VI., 



figs. 11-22, and PL VII., 

 figs. 1, 2. 



Thompson & Scott, 1903, p. 



248. PL II., figs. 24-26. 



A. Scott, 1909, p. 116. 



Sewell, 1912, p. 363. 



Numerous examples of both sexes were obtained in the 

 present collections. The male was first obtained by Thompson 

 and Scott, but as they give no descrixDtion of its structure I 

 give below a brief account of some of the more saHent features. 



