Plate 4 



Figures 1-3. Dixcorbis chasteri (Heron-Allen and Earland). X 200. (After 

 Heron-Allen and Earland.) Figs. 1, 2, Dorsal views. Fig. 3, 

 Ventral view. 

 4 a, h. Z)?scor6?s c/ias^en (Heron-Allen and Earland) . X 150. From off 

 Faroe Islands, a, dorsal view-; b, ventral view. 



5. Discorbis chasten (Heron-Allen and Earland), var. bispinosa 



(Heron-Allen and Earland). X 200. (After Heron-Allen and 

 Earland.) 



6. Discorbis chasteri (Heron-Allen and Earland), var. bispinosa 



(Heron- Allen and Earland). X 150. From off Faroe Islands. 

 7, 8. Discorbis fioridana Cushman. X 100. a, a, dorsal views; b, b, 

 ventral views; c, c, peripheral views. Fig. 7, Montego Bay, 

 Jamaica. Fig. 8, Dry Tortugas, Fla. 

 9 a-c. Discorbis globidaris (d'Orbigny). X 100. Dogs Bay, Ireland. 

 a, dorsal view; b, ventral view; c, peripheral view. 

 10 a-c. Discorbis globidaris (d'Orbigny), var. anglica Cushman, new 

 variety. X 50. Off Nose Head, Moray Firth, a, dorsal 

 view; b, ventral view; c, peripheral view. 



149 



