48 ROYAL SOCIETY OF CANADA 
PLATE VI. 
Fig. 13.—Heteropia Rodgeri (page 35). Twice the natural size. 
Fig. 13a. Part of a horizontal section; X 136. The dermal oxea 
parallel to the long axis of the sponge are shewn in transverse 
section. - 
Fig. 130. Gastral quadriradiate spicule ; X 272. 
Figs. 13c, 134. Gastral triradiate spicules ; X 272. 
Fig. 13e. Subgastral triradiate spicule ; X 272. 
Fig. 12f. Subdermal triradiate spicule ; X 272. 
Fig. 13g. Dermal oxeote spicule ; X 136. 
Fig. 14—Grantia invenusta (page 32). Twice the natural size. 
Fig. 14a. Part of a horizontal section; X 136. 
Fig. 140. Gastral quadriradiate spicule ; X 272. 
Fig. 14c. Gastral triradiate spicule ; X 272. 
Fig. 144. Tubar triradiate spicule ; X 272. 
Figs. 14e, 14f. Dermal triradiate spicules ; X 272. 

