1 



PLATE XXIX. 



Cassidulus .EQiOKEis Mortoii (page 68). 



Fig. la. Upper surface of the test. 

 1ft. Lower surface of the test. 

 Ic. Lateral view of the same. 

 Id. Posterior view of the same. 

 If. Auterior ambulacrum. 



1/. Several plates, petaloidal region of the same, much enlarged. 

 Ig. Ditto, oral region. 

 Ih. Apical disk, much enlarged, 

 li. Diagram showing the arrangement of the plates about the peristomial 



opening. 

 162 



