PLATE 37. 
Fig. 
523. 1. Stromatopora concentrica. (Pag. 136.) 
1 a. The surface of a small hemispheric mass, showing the edges of the thin laminae which are unequally 
weathered. 
1 b. A magnified portion of the same surface, showing the circular ends of the cylindrical tubes. 
1 c. A magnified portion, showing the weathered edges of successive laminae which are indented by the cells, 
giving them the appearance of being arranged in concentric lines. 
1 d. A transverse section of a small mass. 
1 e. A magnified portion of the same. 
1 /. A larger mass, showing the effects of weathering upon the thin concentric laminai. 
1 g. The base of the same specimen, showing several centres of growth. 
