Explanation of the plates. 



Pl. I. 



Pterygocera arenaria, 6 times enlarged. 



The superior antenriEe. 



The inferior antennas. 



The second pair of maxillse. 



The first pair of maxillse. 



The maxillipedes. 



The left masilliped. 



The first pair of gnathopoda. 



8 a. The dactylus of the first pair of gnathopoda. 

 The second pair of gnathopoda. 



9 a. The dactylus of the second pair of gnathopoda. 



Pl. II. 



» 10. The first pair of pereiopoda. 



» 11. » second » 



» 12. » third » 



» 13. » fourth » 



» 13 a. Group of spines from the third joint of the fourth pair of 



pereiopoda. 

 » 14. The fifth pair of pereiopoda. 

 » 15. Group of spine-bristles from the third joint of the same pair 



of legs. The same form appears also at the inferior 



antennae. 

 » 16. Ranges of tactile bristles from the lower side of the carpus 



of the first pair of gnathopoda. 

 » 17. The urus. 

 » 18. Pterygocera with folded legs. 



Plate III. 



» 19. Spine with feeling-hair from uropoda. 



» 20. » from the fourth pair of pereiopoda. 



» 21. » » the peduncles of the pleopoda. 



» 22. \ 



go f Spines from the maxilliped. 



