EXPLANATION OF PLATE XXIII. 



Thuiaria divergent, sp. nov. 



Fig. 1 Portion of main stem, with proximal half of a pinna, magnified. 

 2 Distal half of pinna, magnified. 

 3 Portion of pinna with gonangium, highly magnified. 



Plumularia clavicula, sp. nov. 



4 Portion of hydrocladium, magnified ; front view. 

 5 Portion of hydrocladium, magnified ; lateral view. 

 6 Distal portion of a corbula, showing the origin of the costa from 

 the mesial sarcotheca. 



Reproduced from drawings made by Thomas Whitelegge, Junr. 



