i 



Plate 29. 



1-4. Dermatodiadema horridum A. Ag. 



1. The odd anterior ambulacrum of a specimen measuring 10.5 mm. in diameter with 



primary tubercles ; Station 33()3. 



2. Tlie left anterior interambulacrum of the same specimen as fig. 1 (Actinal syst. PL I 



tig. 4). 



3. The odd anterior ambulacrum of a specimen measuring 20 mm. in diameter \\ 



7-8 primary tubercles ; Station 3413. 



4. The left anterior interambulacrum of tlie same specimen as fig. 3 (Abactinal syit^ 



28, fig. 1; actinal syst. PI. 2G, fig. 1). 



I, 

 5-7. Dermatodiadema globulosum A. Ag. 'i 



5. The left posterior ambulacrum of a specimen measuring 25 mm. in diameter 



8-9 i)rimary tubercles; Station 3398. 



G. The left posterior interambulacrum of the same specimen as fig. 5 (Abactinal 

 PI. 28, fig. 3). 



7. The abactinal part c)f the right anterior ambulacrum of a specimen measuring 30 

 (Abactinal syst. PI. 28, fig, 4 ; actinal syst. Pi. 20, fig. 2); Station ;r.Sl. 



