122 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 148 



Page 

 1, 2, Lateral and dorsal views of incomplete cranidium, X4, 3, 4, Free 

 cheeks, x4 (coll. cnk/1) ; U.S.N.M. 144694, plesiotypes. 



Figs. 5-8. Crepicephalus convergcns Rasetti, n. sp 46 



5, Pygidium, x2 (coll. cnk/1) ; U.S.N.M. 144567, paratype. 6, Pygid- 

 ium, X2 (coll. cnk/1) ; U.S.N.M. 144566, holotype. 7, Exfoliated 

 cranidium, x5. 8, Portion of cranidium showing ornamentation, XS 

 (coll. cnk/1) ; U.S.N.M. 144567, paratypes. 



Figs. 9-11. Crepicephalus cf. convergcns Rasetti 46 



9, 11, Exfoliated pygidia, x2 (coll. cnn/3) ; U.S.N.M. 144568. 10, Ex- 

 foliated pygidium, x2 (coll. cnn/1) ; U.S.N.M. 144569. 

 Figs. 12, 13. Crepicephalus ? sp. undet. No. 2 47 



12, Rubber cast of internal surface of cranidium, X2. 13, Exfoliated 

 pygidium, x2 (coll. cnn/3) ; U.S.N.M. 144571. 



Figs. 14-16. Llanoaspis walcotti Resser 70 



14, Rubber cast of external impression of cranidium, xS. 15, 16, Py- 

 gidia, X5 (coll. cnn/3) ; U.S.N.M. 144625, plesiotypes. 



Figs. 17, 18. Crepicephalus, sp. undet. No. 1 47 



17, Rubber cast of internal surface of pygidium, x2. 18, Exfoliated py- 

 gidium, X2 (coll. cnn/4) ; U.S.N.M. 144570. 



Fig. 19. Undetermined cranidium No. 2 112 



Cranidium, X5 (coll. cnk/1) ; U.S.N.M. 144730. 



Fig. 20. Madarocephalus laetus Resser 44 



Cranidium, XlO (coll. cnm/2) ; U.S.N.M. 144563, plesiotype. 



Figs. 21-28. Kingstonia inflata Resser 60 



21, 22, Lateral and dorsal views of pygidium, x5. 25, Pygidium, X5. 

 26, Photograph of cranidium taken under water, x5, showing lighter 

 stains probably corresponding to muscle attachments on interior sur- 

 face (coll. cnm/2) ; U.S.N.M. 144605, plesiotypes. 23, Exfoliated py- 

 gidium, x5 (coll. cnn/1) ; U.S.N.M. 144606, plesiotype. 24, 28, Lateral 

 and dorsal views of cranidium, x5. 27, Cranidium, x5 (coll. cnk/1) ; 

 U.S.N.M. 144607, plesiotype. 



Fig. 29. Undetermined cranidium No. 1 112 



Cranidium, x5 (coll. cnn/3) ; U.S.N.M. 144729. 



Fig. 30. Crepicephalus cf. scissilis Resser 45 



Exfoliated pygidium, X2 (coll. cnn/3) ; U.S.N.M. 144564. 



Plate 9 



Figs. 1-8. Blountia arcuosa Resser 55 



1, 2, Dorsal and frontal views of cranidium, X 5. 3, 4, Dorsal and lateral 

 views of cranidium, x5. 5, Pygidium, x4. 6, Exfoliated pygidium, 

 X5. 7, 8, Dorsal and lateral views of pygidium, x5 (coll. cnm/3) ; 

 U.S.N.M. 144555, plesiotypes. 



Figs. 9-12. Blountia alexas Walcott 56 



9, Cranidium, x5. 10, 11, Dorsal and lateral views of cranidium, x5 

 (coll. cnk/1) ; U.S.N.M. 144596, plesiotypes. 12, Pygidium, xS 

 (coll. cnk/3) ; U.S.N.M. 144701, plesiotype. 

 Figs. 13-20. Blountia montanensis Duncan 57 



13, 16, Dorsal and lateral views of cranidium, x5. 14, Free cheek, x5. 

 15, Pygidium, x5 (coll. cnk/1); U.S.N.M. 144598, plesiotypes. 17, 

 Lateral view of large cranidium, x3. 18, Pygidium, x5. 19, Ex- 

 foliated pygidium, x2. 20, Cranidium, xS (coll. cnm/2) ; U.S.N.M. 

 144599, plesiotypes. 



