^2 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL, 57 



DESCRIPTION OF PLATE 3 



PAGE 



Sidney ia inexpcctans Walcott 24 



Fig. I. A portion of a branchial leal or lamella showing something 

 of the structure. X 3- U. S. National Museum, Catalogue 

 No. 57486. 



2. Enlargement (X2) of the posterior segments of a specimen 



showing what appears to have been the contents of the ali- 

 mentary canal. U. S. National Museum, Catalogue No. 57489. 



3. Enlargement (X2) of the caudal fin of the specimen repre- 



sented by fig. 2, pi. 5. 



4. Enlargement (X2) of the caudal fin of the specimen repre- 



sented by fig. I, pi. 2. 



