136 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 57 



DESCRIPTION OF PLATE 19 



PAGE 



Ottoia proMca Walcott 128 



Fig. I. (X2.) A small specimen enlarged to show the hooks about 

 the mouth, proboscis, and posterior end, also the distinct 

 annular lines and segments. U. S. National Museum, Cata- 

 logue No. 57619. 



2. (Natural size.) An adult annelid showing the enteric canal and 



mouth, with the proboscis broken off. U. S. National 

 Museum, Catalogue No. 57620. 



3. (X 2.) Posterior end of a small specimen in which the annular 



lines and hooks are very distinct. U. S. National Museum, 

 Catalogue No. 57621. 



4- (X3.) Enlargement of a proboscis, belt of hooks, and a por- 

 tion of the anterior end of the body. The outlines of the 

 enteric canal are clearly defined as well as the belt of hooks 

 and the papillae on the proboscis. U. S. National Museum, 

 Catalogue No. 57622. 



5. (Natural size.) Adult annelid preserving very distinctly the 

 annular lines and segments, ring of hooks, and proboscis. 

 U. S. National Museum, Catalogue No. 57623. 



Selkirkia major (Walcott) 120 



Fig. 6. (X 3-) A flattened tube with the anterior portion of the animal 

 projecting from it. U. S. National Museum, Catalogue No. 

 57624. 



t 



Hyoli flies carinatus Matthew 121 



Fig. 7. (X2.) Ventral view of shell, operculum and fin or arm sup- 

 ports. This is one of a number of specimens showing the 

 curved fin supports. U. S. National Museum, Catalogue 

 No. 57625. 



Selkirkia fragilis (Walcott) 122 



Fig. 8. (X^-) Typical form of the tube as it is flattened in the 

 shale of locality (14s) Middle Cambrian: about 2300 feet 

 (701m.) above the Lower Cambrian and 2700 feet (823 m.) 

 below the Upper Cambrian, in the Ogygopsis zone of the 

 Stephen formation, at the great " fossil bed " on the north- 

 west slope of Mount Stephen, above Field on the Canadian 

 Pacific Railway, British Columbia, Canada. U. S. National 

 Museum, Catalogue No. 57626. 



Selkirkia gracilis (Walcott) 122 



Fig. 9. (Natural size.) Type specimen, flattened in the shale. U. S. 

 National Museum, Catalogue No. 57627. 



With the exception of fig. 8, all of the specimens illustrated on this plate are 

 from locality (35k) Middle Cambrian: dark siliceous shale in the Burgess 

 shale member of the Stephen formation on the west slope of the ridge be- 

 tween Mount Field and Wapta Peak, one mile (1.6 km.) northeast of Burgess 

 Pass, above Field, British Columbia. 



