186 Mr. J. S. Dunkerly on the Choanojlagellate 



of the new species of what may be a vestige of the inner 

 flagellum. The only Isopoda in which any trace of this 

 flagellura has been found hitherto are the gigantic Bathy- 

 nomus and the cryptoniscan larva? of some Epicaridea. 



EXPLANATION OF PLATE V. 



Fig. 1. Chelura insulce, ovigerous female, from the side. 



Fig. 2. Ditto. Posterior part of body, from above. 



Fig. 3. „ Gnathopod of first pair. 



Fig. 4. „ Gnathopod of second pair. 



Fig. 5. ,, Pleopod of second pair. 



Fig. 6. ,, Adult male, from the side. 



Fig. 7. Limnoria andrewsi, female, from above. 



Fig. 8. Ditto. Antennule. * Supposed vestige of inner flagellum. 



Fig. 9. ,, Antennae. 



Fig. 10. „ Mandible. 



Fig. 11. „ Maxilliped. 



Fig. 12. „ Gnathopod of first pair. 



Fig. 13. „ Terminal part of same, further enlarged. 



Fig. 14. ,, Uropod. 



XXVII. — Notes on the Choanojlagellate Genera Salpingceca 

 and Polyceca, with Description of Polyceca dumosa, sp. n. 

 By J. S. Dunkerly, B.Sc, Assistant in Zoology Depart- 

 ment, Birkbeck College, London. 



[Plates VI. & VII] 



The Choanoflagellata have been little studied of late, and 

 after observing several freshwater forms, I spent a month of 

 1909 at the Plymouth Biological Station, in order to obtain 

 some knowledge of the marine members of the family. I 

 should like here to express my sincere thanks to the British 

 Association for the Advancement of Science for permission 

 to use their table, and also to the staff of the Laboratory for 

 their kind assistance. My work on these forms has received 

 the kindest encouragement and assistance from Professor 

 Minchin, who has allowed me to work at the Lister Institute. 



Salpingceca. 



Salpingoeca was established as a genus by James Clark (i), 

 and Saville Kent discovered a large number of different forms. 

 That all of Saville Kent's so-called species are truly such is 

 more than doubtful : e.g., France has pointed out that Kent's 

 figures of Monosiga ovata (2, pi. II. fig. 33) and Af. consociata 



