242 College of Forestry 



PLATE B 



Explanation of Figures 

 All drawings were made with the aid of the camera from type mate- 

 Spongilla heterosclerifera nov. sp. Figures 1-5 x 220, 6-8 x 55. 



Skeleton spicules. 



Gemmule amphistrongyli from the foraminal side of the gem- 

 mule layer. 



Gemmule amphistrongjli from the substratum side of the 

 gemmule layer. 



Gemmule amphioxi from the substratum side of the gemmule 

 layer. 



Cellular pneumatic layer near the substratum with included 

 spicules. 



Cross section of gemmule layer showing spicules of only the 

 foi-aminal surface. 



Foraminal surface of gemmule layer showing only superficial 

 spicules. 



Substratum surface of gemmule layer. 



