396 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 57 



DESCRIPTION OF PLATE 62 



Dikeloccphalus vanhorni Walcott 373 



Fig. I. (Natural size.) Type specimen of cranidium. 



2. (Natural size.) Thoracic segment associated with this species. 



3. (Natural size.) Pygidium associated with the cranidium rep- 



resented by fig. I. 

 The three specimens represented by figs. 1-3 are from the Upper 

 Cambrian: St. Lawrence formation, (346d) Hoka, Houston County, 

 Minnesota. They are lot No. 14393, Walker Museum, University of 

 Chicago. Plastotype U. S. National Museum, Catalogue 

 No. 58608, a, b, c. 



Dikeloccphalus minncsotciisis Owen ??. (See pis. 60, 61, 66) 369 



Fig. 4. (Natural size.) Fragment of cranidium. From locality 78b, 

 Upper Cambrian : St. Lawrence formation, 50 feet (15.2 m.) 

 above the St. Croix River, near the landing at Osceola, 

 Polk County, Wisconsin. U. S. National Museum, Cata- 

 logue No. 58609. 



5. (Natural size.) Hypostoma from about the same horizon as 



fig. 4. (78.) U. S. National Museum, Catalogue No. 58610. 



6. (Natural size.) Fragment of thoracic segment associated with 



fig. 5. (78.) U. S. National Museum, Catalogue No. 58611. 

 The specimens represented by figs. 5 and 6 are from locality 78, 

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

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



