252 CEYLON PEARL OYSTER REPORT. 



Labidocera kroyeri (Brady), var. stylifera, nov. — Plate II., figs. 8, 9. 



Male differs from L. kroyevi like the variety gaUenais in the last thoracic segment 

 and in the 5th natatory legs. The hasal portion of the latter is produced into a long 

 rod-like projection. Several specimens were taken at different stations round Ceylon. 



Labidocera pectinata, n. sp. — Plate II., figs. 10 to 14. 



Length, female, 2 - l millims. Male unknown. 



Cephalothorax 5-jointed, robust in centre, slightly tapering towards each end, the 

 terminal segment having strong lateral spinous projections. Ptostrum short, bifid at 

 apex. Anterior antennae 23-jointed, in length about equal to the cephalothorax. 



The relative lengths of the joints are 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. 

 6. 16. 2. 2. 2. 4. 4. 6. 5. 5. 8. 10. 10. 12. 16. 14. 16. 16. 10. 10. 10. 9. 9. 



Posterior antennae aiid mouth organs and 1st to 4th pairs of natatory legs as in the 

 other members of this genus. Abdomen 3-jointed, about one-third as long as the 

 cephalothorax ; the right basal extremity of the genital segment is produced into two 

 curved spines ; the middle joint bears a knobbed protuberance. The furcal rami 

 are slightly asymmetrical, the right one being nearly half as large again as the left ; 

 the inner side of each is lined with fine hairs ; each furca terminating in five short 

 setae. Fifth natatory legs, each composed of two 1 -jointed branches, asymmetrical, 

 the inner branches being differently denticulated ; both branches of the left leg are 

 larger than those of the right. The characters of the abdomen and 5th natatory legs 

 are unlike those of any other species known to us. 



Four specimens, all females, were taken in Palk Straits, Ceylon. 



Pontella fera, Dana. 



Found at 3 stations, viz., twice off Minikoi, Indian Ocean, and at Vankali Paar, 

 Ceylon. 



Pontella securifer, Brady. 

 Taken off Minikoi, Indian Ocean, and at 10 stations round Ceylon. 



Pontella princeps, Dana. 

 Was found once only, at Chilaw Paar, Cejdon. 



Pontella tenuiremis, Giesbb. 



Was found once only, in Palk Strait, Ceylon. Giesbrecht's specimen was from 

 the Pacific Ocean. 



Pontella danae, var. ceylonica, nov. — Plate II., figs. 1 to 5. 



Length, female 3'4 millims. 



Cephalothorax of nearly the same width throughout, in this respect differing from 



