NO. 13 DIKELOCEPHALUS AND OTHER GENERA 4O7 



Saukia leucosia Walcott— Continued. page 



Fig. 16. (X I-S-) View of a smaller cranidium than that of fig. 14. 

 The photograph is from a wax impression taken from a 

 hatural matrix. U. S. National Museum, Catalogue No. 

 58642. 

 17 and 170. (X I-5-) Dorsal and side views of a fragmentary 

 pygidium associated with the cranidia represented by figs. 14 

 and 16. U. S. National Museum, Catalogue No. 58643. 

 The specimens represented by figs. 14-170 are from locality 78, 

 Upper Cambrian : St. Lawrence formation ; quarry near St. Croix 

 River, in suburbs of Osceola, Polk County, Wisconsin. 



Saukia pyreiie Walcott 382 



Figs. i8 and i8a. (Natural size.) Dorsal and side views of type specimen 

 of the cranidium. U. S. National Museum, Catalogue 

 No. 58644. 

 19. (Natural size.) Free cheek. U. S. National Museum, Cata- 

 logue No. 58645. 

 20 and 20fl. (X 2.) Dorsal and side views of pygidium referred to 

 this species. U. S. National Museum, Catalogue No. 58646. 

 The specimens represented by figs. 18-20 are from locality 78, 

 Upper Cambrian : St. Lawrence formation ; quarry near St. Croix 

 River, in suburbs of Osceola, Polk County, Wisconsin. 



Saukia fallax Walcott 378 



Figs. 21 and 21a. (Natural size.) Dorsal and side views of a cranidium 

 from locality 70a, Upper Cambrian : Wilberns formation, 

 Baldy Mountain, near Morgans Creek, Burnet, Burnet 

 County, Texas. U. S. National Museum, Catalogue 

 No. 58647. 

 22 and 220. (Natural size.) Dorsal and side views of a pygidium 

 from the same locality (70a) as the specimen represented 

 by figs. 21 and 21a. U. S. National Museum, Catalogue 

 No. 60682. 



