Plate 10. 



Fig. 1. Sclerotliamnopsis compressa. From a photograph ; \. 

 " 2. Bathyxiphus, spj. From a photograph. A small piece has been taken out, and 



the two parts fastened together with a pin ; \. 

 " 3. ScUrothmmiojisis compiressa. From a photograph ; j. 

 " 4. Hexactinella luhyrintlnca. Scopula; upper and lower ends; x 600. 

 " 5. Chonelasma calyx F. E. Sch. (sp.?). From a photograph. Sponge wall cut away 



so as to show septum ; 4^. 

 " G. Hexactinella lahyrinthica. From a photograph ; \. 

 " 7. " " Group of slender, spiuose hexacts and pentacts, 



partially fused ; x 300. 



