Plate 9. 



Fig. 1. Ewrete erectuw gracile. Gastral scopula; x 450. 



2. Sclerothamnnpsis cnvipressa. From a photograph ; \. 



3. Enrete erectum gracile. Gastral scopula; x 450. 



4. Sclerothamnopsis covipressa. From a photograph ; two of the smallest branches 



shown ; x 2. 



5. Eiirete -erectum gracile. From a photograph ; \. 



6. Sclerothamnopsis compressa. Pinulus ; x 170. 



7. " " Oxyhexaster; x 250. 



8. " " Upper end of scopula ; x 250. 



9. Regadrella, s]). Skeletal framework ; from a photograph ; |i. 



10. Sclerothamnopsis compressa. Spinose hexact ; x 170. 



11. " " Skeletal reticulum ; from a transverse section. 



Upper margin of figure represents surface of 

 sponge ; x 70. 



