GKETAGEOUS PERIOD. . 205 



AllTICULATA. 



Class VERMES. ■ 



Oeder TUBICOLA. 

 Family SERPULID^. 



Genus SERPULA Linnseus, 1758. 



Serpula intrica White. 



Plate XV, iig. 5 a. 



Tubes small, slender, cylindrical, smooth, very long and very tortuous, 

 not perceptibly increasing in size, so far as our examples show, but neither 

 the distal nor proximal extremity of the tube has been found unbroken. 



Diameter of the tube, a little more than one millimeter. 



This species is remarkable for the great length and uniform size of the 

 tubes, and for the intricacy of their contortions. 



Position and locality. — Sti'ata of the Cretaceous period; southeast of 

 Paria, Utah. 



