CELLULARIAD^. 



11 



Scrupocellaria (Van Beneden). Cell witli a wMp 

 beliind, and a sessile bird's-liead at the upper and 

 outer angle ; aperture spinous. 



S. scriipea. 



scru]30sa. Fig. 11 ; n.s. and mag. 



9 A^ 



10 



Cauda (Lamx.). Cell with a whip in a notch in 

 the outer side ; no bird's-head on the angle. 



C. reptans. Fig. 12 ; n.s. and mag. 



