Phylum VI. ANNULOSA. 



Class Annelida MacLeay (Vermes in part). 



The annelids or segmented worms have ciliate, elongate, bilateral 

 bodies, divided externally into a number of rings representing a 

 corresponding or smaller number of divisions of the internal parts. 

 They are marine, fresh-water, or terrestrial animals, whose re- 

 mains can seldom be preserved in the fossil state. It is only the 

 tube-building suborder (Tubicola) and the free-swimming, preda- 

 ceous suborder (Errantia) which leave any satisfactory remains. 

 In the former the tube is either a calcareous secretion of the animal 

 or it is composed of agglutinated sand and other foreign particles, 

 being in each case wholly external. Presumably belonging to the 

 latter division are the Conodonts, supposed to be the oesophageal 

 jaws of the animals. Besides these two types of fossils, worm 

 burrows are often preserved by sand or mud infiltration, producing 

 a solid mold of the burrow in the strata. 



Literature. 

 1879. Hinde, G. J. On Conodonts from the Chazy and Cincinnati 



Groups ; and on Annelid Jaws from the Cambro-Silurian, Silurian, 



and Devonian Formations in Canada, etc. Quart. Jour. Geol. Soc, 



vol. 35. PP- 351^ 370- 

 1886. Clarke, J. M. Annelid Teeth from the Lower Portion of the 



Hamilton Group, New York. 6th Ann. Rep. State Geol. 

 See also: Newberry, Pal. Ohio, vol. 2, 1875 j Nicholson, Geol. Maga- 

 zine, 1873; X., 1874; N. S., I.; Hall, J., Pal. N. Y., A^ols. II. 



and v., Pt. II., Supplement; Emmons, E., Taconic System, 1844. 

 1906. Sarle, C. J. Arthrophycus and Daedalus of Burrow Origin, and 



Preliminary Note on the Nature of Taonurus. Proceedings Rochester 



Academy of Sciences, vol. 4, pp. 203-214. 

 1902. Woodworih, J. B. On the Sedentary Impression of the 



Animal whose Trail is known as Climactichnites. Bull. 69, N. Y. 



State Mus. Nat. History, pp. 959-966. 

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