284 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 57 



DESCRIPTION OF PLATE 39 



PAGE 



Climactichniies youngi (Chamberlin). (See pi. 38) 259 



Fig. I. (Natural size.) Portion of a trail where the animal made a 

 very irregular track and thus recorded the fact of its having 

 a very flexible under surface. U. S. National Museum, Cat- 

 alogue No. 58546. 

 2. (Reduced about one-seventh.) Portion of a very regular trail, 

 showing forward-curving transverse furrows made by 

 pressing the beach sand backward in creeping, also curved 

 lines made by the impression of the very fine, forward- 

 arching transverse ridges on the ventral surface of the 

 animal. U. S. National Museum, Catalogue No. 58545. 

 Both specimens represented are from locality (99c) Upper Cam- 

 brian, near New Lisbon, Wisconsin. 



