OSTRACODA. 381 



with seven short, stout teeth on the lower portion ; posterior almost rectangularly 

 truncated, produced below the middle, where it bears two teeth and one or two 

 crenulations ; dorsal margin highest in front, sloping with a sinuous curve gently 

 backwards ; ventral sinuated in front and convex behind ; seen from above ovate, 

 with produced emarginate extremities, sharply constricted in the middle and near the 

 posterior end, width equal to half the length ; surface of the shell covered with large 

 irregularly angulated fossae, marked with a strong marginal ridge and an obliquely 

 transverse one, coursing from the posterior towards the anterior extremity ; highest 

 at the posterior end ; size, 073 millim. 



In the general washings, in washings from Gulf of Manaar sponges, and in a 

 dredging from Karativo Paar. Named after Dr. J. C. WILLIS, Director of the 

 celebrated Botanic Gardens at Peradeniya, Ceylon. 



Cythere colletti, n. sp. Plate II., figs. 29 and 30. 



Shell seen from above subquadrangular with compressed margins, height equal to 

 slightly less than two-thirds of the length ; anterior extremity broad and obliquely 

 rounded, with 10 short, stout teeth on the lower portion ; posterior narrowed, 

 truncated, produced near the middle into a quadri-crenulate projection ; dorsal margin 

 highest in front, sloping rather steeply to the posterior ; ventral slightly sinuated in 

 front, convex behind the middle, rising quickly near the posterior, where there is a 

 strong, stout incurved tooth ; seen from above doubly triangular, widest slightly 

 behind the middle, width rather more than half the length, the margins near the 

 posterior end are produced into strong teeth ; anterior extremity blunt and produced 

 into the rnucronate processes, posterior truncate ; surface of the shell marked with 

 curved ridges and rows of impressed puucta ; each valve has a strong tooth near the 

 lower margin of the posterior end ; size, 0'5 millim. 



In washings from Gulf of Manaar sponges. 



Named after the late Mr. OLIVER COLLETT, a well-known naturalist in Ceylon. 



Cythere holdsworthi, n. sp. Plate II., figs. 31 and 32. 



Shell seen from the side subrhomboidal, height equal to fully two-thirds of the 

 length ; anterior extremity broad and obliquely rounded, posterior truncated, with a 

 small projection in the centre ; dorsal margin boldly arched, highest in the middle ; 

 ventral convex in the middle ; seen from above broadly ovate, widest near the 

 middle, width equal to two-thirds of the length ; anterior extremity narrowed and 

 bluntly rounded ; posterior broadly rounded, almost truncate ; surface of the shell 

 marked with concentric rows of impressed puncta ; size, 0'5 millim. 



In general washings from dredged invertebrata from Gulf of Manaar. 



Named after Mr. HOLDSWORTH, the naturalist who investigated the pearl banks in 

 1868. 



