SURFACE COPEPODA OF THE GULF OF MANNAR. 217 



Scolecithrix danss, Wolfenden, 1905, p. 1009. 



A. Scott, 1909, p. 88. 



SeweU, 1912, p. 300. 



This species was comparatively rare in the collection. 



Ceniis Scolecithricella, vSars. 



SCOLECITLIRICELLA PEARSONI, sp. nov. 



(PI. XVII., figs. 6, 7, and PI. XVIII., figs. 1-4). 



A single male and several females of a species of Scoleci- 

 thricella -were obtained at Dutch Moderagam and Karativu 

 Paars. The examples appear to belong to a hitherto unde- 

 scribed species, and I have given it the above name after 

 Dr. J. Pearson, the Director of the Colombo Museum, who 

 kindly entrusted the present collection from the Ceylon pearl 

 banks to my care for the purpose of examination. 



The characters of the above species are as follows : — 



$. Total length, I'O mm. 



The proportions of cephalothorax and abdomen are 3*5 : 1. 



The cephalothorax is robust, and is uniformly rounded 

 dorsally. The head and first thoracic segment are fused 

 together, as also are thoracic segments 4 and 5. The rostrum 

 consists of two stout spinous processes. The abdomen has 

 four segments, showing with the furcal rami the following 

 relative proportional lengths : — 6:3:3:1:2. 



The first antenna is short and reaches, when folded back, to 

 the posterior end of the thorax : it consists of twenty joints 

 having the following proportional lengths : — 



Segments : 1-2. 3. 4. 5. 6. 7. 8-10. 11. 12-13. 14. 



102 27 23 2.3 23 23 58 23 51 39 



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



43 47 47 51 51 51 58 66 89 105 



The first and second, eighth to tenth, and twelfth and 

 thirteenth segments are respectively fused together, and so 

 are the twentj^-fourth and twenty-fifth. 



