Plate 26. 



1, 3, 4. Dermatodiadema horridum A. Ag. 



1. Actinal system of specimen measuring 20 mm. in diameter ; Station 3413. 



3. Left posterior ambulacrum of specimen measuring 9 mm. in diameter with 6-7 piv 



mary tubercles ; Station 3364. 



4. Odd anterior ambulacrum of a specimen measuring 19 mm. in diameter with 7-8 prin 



mary plates ; Station 3413. 



2. Dermatodiadema globulosum A. Ag. 



2. Part of actinal system of specimen measuring about 30 mm. in diameter; the righ^ 



anterior ambulacrum extends upwards ; Station 3381. 



