298 Proceedings of the Royal Physical Society. 



be confined to the arctic or subarctic seas. There seems to 

 be little doubt that Cetochilus septentrionalis is identical with 

 Calanus helgolandicus, Claus, and having priority in publica- 

 tion, it should have preference over C. helgolandicus. 



Family Paeacalanid^, G. 0. Sars, 1902. 

 Genus (2) Paracalanus, Boeck, 1864. 



2. Paracalanus parvus (Claus). 



1863. Calanus parvus, Claus, Die frei-lebenden Copepoden, p. 173, 



pi. xxvi. figs. 10-14; pi. xxvii. figs. 1-4. 



Hah. — Occasionally taken with the tow-net near the sea- 

 ward limits of the Forth estuary, sometimes in moderate 

 abundance, but usually it is a rather scarce species. 



Family Pseudocalanid^. 

 Genus (3) Pseudocalanus, Boeck, 1872. 



3. Pseudocalanus elongatus, Boeck. 



1864. Clausia elongata, Boeck, Forhandl. Videnskabs-Selskabet, 



Christiania (1864), p. 9. 



Hab. — Common throughout the estuary. Boeck described 

 this species as Clausia elongata, but as that generic name had 

 been previously used by Claparede for a genus of parasitic 

 Copepods, he withdrew it and substituted the name Pseudo- 

 calanus. 



Family Mtideivm. 

 Genus (4) Bradyidius, Giesbrecht, 1897. 



4. Bradyidius armatus (G. S. Brady). 



1878. Pseudocalanus armatus, G. S. Brady, Monogr. Brit. Copep., 

 vol. i. p. 46, pi. iv. figs. 1-11. 



1897. Bradyidius armatus, Giesbrecht, Zool. Anzeiger, No. 536. 



1898. ,, ,, T. Scott, Sixteenth F.B. Kept., pt. iii. 



p. 264, pi. xii. figs. 1-19. 

 1902. Undinopsis Bradyi, G. 0. Sars, Crustacea of Norway, vol. iv. 

 p. 32, pis. xix., xx. 



Hab. — Off St Monans and a few other places near the 



