PLATE XXII. 





[Photo-microijraphs by A. ScOTT. 

 Fig. 1. — Plankton showing (a) Biddulphia mobiliensis and (6) B. sinensis. 



Fig. 2. — Xauplius stage of Balanus. 

 X 30. 



Fig. 3. — Cypris stage of BaJanus. 

 X 30. 



