PLATE CXI. 



Amphistegina. — Cycloclypeus. 



Diam. Page 



Figures 1-7. — Amphistegina lessonii, d'Orbigny, . x 30 740 



a, Superior lateral aspect ; b, inferior lateral aspect ; 



c, peripheral aspect. 

 Figs. 1-4. Typical, compressed, lenticular form. 

 Figs. 5, 6. Thick variety, commonly inequilateral. 

 Fig. 7. Thick, very inequilateral or dome-shape 

 variety. 



,, 8.- — Cycloclypeus guembelianus, Brady, . x 35 751 



a, Lateral aspect ; b, peripheral aspect. 



