PLATE XLVIIT. 



Figure 1. Hipponoe proavia, Duncan and Sladen (page 310). Profile view of the test, natural 

 size. 



2. Actinal view of the samCj natural size. 



3. Interradial plates, to show ornamentation, magnified. 



4. Part of the ambulacral area, to show the composition of the plates, magnified. 



4 a. Diagrammatic sketch of ambulacral plates, to show the disposition of the ornamen- 

 tation, magnified. 



