PLATE LXVI. 



Cassidulus (Rhynchopygus) raveneli Twitchell, n. sp. (p. 142). 

 Am. Mus. Nat. Hist., specimen B. 



Figure la. Upper surface of the test. 



lb. Part of one ambulacrum, X 

 lc. Apical system, X 8. 



Cassidtjlus (Rhynchopygus) raveneli Twitchell, n. sp. (p. 142). 



Am. Mus. Nat. Hist., specimen C. 



Figure 2a. Lower surface of the test. 

 2b. Part of floscelle, X 4. 



Cassidtjlus (Rhynchopygus?) patelliformis (Bouve) (p. 143). 

 Boston Soc. Nat. Hist. 1558, type. 



Figure 3a. Upper surface of the test. 

 3b. Lower surface of the test. 

 3c. Posterior surface of the test. 

 3d. Lateral surface of the test. 



Cassidulus (Rhynchopygus) depressus Twitchell, n. sp. (p. 144). 

 Boston Soc. Nat. Hist. 1557a, specimen A, type. 



Figure 4a. Upper surface of the test. 

 4b . Lower surface of the test. 

 4c. Posterior surface of the test. 

 4d. Lateral surface of the test. 

 4e. Part of one ambulacrum, X 12. 



Cassidulus (Rhynchopygus) depressus Twitchell, n. sp. (p. 144). 

 Boston Soc. Nat. Hist. 1557b, specimen B. 



Figure 5a. Lower surface of the test. 

 5b. Part of floscelle, X 8. 



