PLATE XVI. 



Page. 



Fig. 1. Dictyoinit7'a Canadensis 108 



2. Dictyomitra polypora 109 



3. Dictyomitra multicostata ' 109 



4. Stichocapsa Tyrrelli 110 



5. Stichocapsa Dawsoni 110 



6. Stelleta sp (a sponge) 



