42 ROYAL SOCIETY OF CANADA 
PrATE VTT 
Fig. 7.—Sycon mundulum (page 28). Twice the natural size. 
Fig. 7a. Part of a horizontal section ; X 136. 
Fig. 7b. Gastral quadriradiate spicule ; X 272. 
Fig. 7c. Gastral triradiate spicule ; X 272. 
Fig. 7d. Tubar triradiate spicule ; X 272. 
Fig. 7e. Oxeote spicule ; X 136. 
Fig. 8—Amphoriscus Thompsoni (page 36). Twice the natural size. 
Fig. 8a. Part of a horizontal section ; X 136. 
Figs. 8b, 8c. Gastral quadriradiate spicules; X 272. 
Fig. 8d. Gastral triradiate spicule ; X 272. 
Fig. 8e. Subgastral triradiate spicule ; X 272. 
Figs. 8f, 8g. Subdermal triradiate spicules; X 272. 
Fig. 8h. Dermal triradiate spicule ; X 272. 
Fig. 8i. Stout oxeote spicule; X 272. 
Fig. 8j. Linear spicule ; X 272. 

