Fig. 4
From: Gymnodiadema and the Jurassic roots of the Arbacioida (stirodont echinoids)
Gymnodiadema hessi sp. nov.; Bajocian, Enjil, Morocco. NHM EE13924 (paratype): a oral view, b apical view, c lateral view, d detail of peristomial region. e NHM EE13923 (holotype); detail of supra-ambital interambulacral plates in unworn region showing numerous glassy papillae (gp). f NHM EE13925 detail showing adoral tubercles (peristome to left). Scale barsa–c 10 mm, d 5 mm, e, f 1 mm