Plate 3. 

 1-6. Dorocidaris panamensis A. Ag. ; Station 3368. 



1. Denuded abactinal system of a specimen measuring 10 mm. in diameter. 



2. Denuded abactinal system of a specimen measuring IS mm. in diameter. 



3. Denuded abactinal system of a specimen having 7 primary coronal plates, measuring 



30 mm. in diameter. 



4. Denuded actinal system of the same specimen as fig. 3. 



5. Part of test, seen facing the odd anterior ambulacrum ; same specimen as fig. 3. 



6. Part of test, seen facing the left anterior interarabulacrum ; same specimen as fig. 3. 



