COPEPODA. 247 



Centropages gracilis (Dana). 



Occurred at 14 stations, the range being much the same as that of the preceding 

 species. 



Centropages kroyeri, Giesbr. 



Found twice in the northern Indian Ocean, in the vicinity of Socotra. ,The 

 western Mediterranean appears to be its only previously known habitat. 



Centropages calaninus (Dana). 

 Occurred at 1 1 stations in the Indian Ocean. 



Centropages orsini, Giesbr. 

 This, like the preceding species, occurs at 11 stations, all in the Indian Ocean. 



Centropages tenuiremis, n, sp. — Plate I., figs. 14 to 18. 



Length, female 2 - minims. ; male 1'8 millims. 



Body somewhat angular, widest anteriorly, slightly tapering to last segment of 

 thorax, which is terminated by long outwardly extended lateral acute projections. 

 Anterior antennae of female 24-jointed, the pnmortional lengths being as follows : — 

 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 

 3. 4. 2. 2. 3. 3. 2. 3. 3. 4. 4. 5. 6. 7. 8. 8. 8. 8. 7. 5. 5. 5. 5. 5. 



Male right antenna 24*-jointed ; joints 13 to 17 are considerably thickened; a 

 geniculation occurs between the 18th and 19th joints. 



Abdomen of female 4-jointed. of male 5-jointed, the last one very small. 



Furcal ramus sub-linear, the length about three times the width. Terminal caudal 

 setae in the female have the basal portion thickened. 



The basal joint of the right 5th natatory leg in the female is acutely produced on 

 the inner side and bears three rows of minute teeth. The 5th legs in the male are in 

 general similar to those of C. typicus, as are the other appendages not alluded to. 



Large numbers of specimens, both male and female, were found at 21 stations 

 round Ceylon. 



The acute lateral terminal thoracic spines, the 5th natatory legs in the female, and 

 the abdomen and furcal rami are the distinguishing features of this species. 



Centropages dorsispinatus, n. sp. — Plate I., figs. 19 to 25. 



Length, female 1'37 millims. ; male 1*24 millims. 



Cephalothorax ovate, the posterior segment having a rounded acute terminal 



projection. Rostrum short, broad and triangular. A remarkable curved beak-like 



hook adorns the median dorsal line of the posterior edge of the cephalic segment. 



Anterior antennae of the female 24-jointed, the proportional lengths being as follows : — 



1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 



.3. 5. 1. 1. 1. 1. 1. 1. 2. 2. 3. 3. 5. 5. 5. 6. 6. 6. 6. 5. 4. 3. 3. 4. 



