PLATE II. 



PAGE. 



Fig. 1. Stromatocerium richmondense, n. sp., polished slab, showing several 



specimens, natural size, 41 



la. View of a transverse section of the central part showing the ends 



of the radiating tubes, magnified about 100 diameters, .... 41 



lb. Showing a longitudinal section of the radiating tubes, and the appear- 

 ance of the concentric laminae, magnified about 100 diameters, . . 41 



Fig. 2. Dystactospongia insolens, n. sp., view of the lower part of a specimen 

 showing the radiating frame work from different points of attachment, 



natural size, . . . . 43 



2a. View of a prepared microscopic slide, magnified three or four diameters, 43 

 2b. Approximate appearance, when magnified 100 diameters, ... 43 



Fig. 3. Pattersonia difficilis, n. sp., specimen appearing as a cluster, natural 



size, . . . . . . . . . . . . . 43 



3a. Showing, approximately, the appearance of the vesicular structure when 

 magnified about 100 diameters, 43 



