886 AxxALS OF iHK Carxegik Museum. 



1 1. Front view of the ceplialon of the same specimen. 



12. The same species. The pygidium of a larger specimen. 



13. The same species. An hypostoma. 



14. Ceraui-iis pompiliiis Billings. A cranidium, one tliird larger than natural size. 

 15- Cerauriis IniJsoni Raymond. A cephalon with incomplete geiia! spines, one 



third larger than natural size. 



16. Pseudosphicrexochus vtiUaiins Billings. An incomplete cephalon, twice nat- 

 ural size. 



17- Pseudosphicrexochus vitlcaims billiugsi. Side view of an incomplete crani- 

 dium, twice natural size. 



18. Pseudosplucrexochus approxiiiius Raymond. A cranidium, twice natural size. 



19. Pseudosplucrexochus chazyensis Raymond. Side view of a specimen with 

 two glabellar furrows, twice natural size. 



20. The same species. A small glabella, three times natural size. 



21. Psetidospharexochus [A^ieszkinaskia) satyrtis Billings. Side view of an in- 

 complete cephalon. 



22. Spliicrexochits parvus Billings. Side view of an incomplete cephalon, enlarged 

 two diameters. 



23. Splucrocorphe goodnovi Raymond. A cephalon lacking the genal spines, en- 

 larged two diameters. 



24. Pterygoinetopiis ininulaius Raymond. A cephalon, one third larger than 

 natural size. 



25. The same species. A small pygidium. 



