ANNELIDA— ERRANTI A. 



XIII. Drepanodus Pander. 



245 



Single, straight or curved teeth of more or less circular or ellip- 

 tical section. 



Example: 63, D. arcuatus Pander Lorraine (Fig. 1537, d, e). 



Fig. 1537. CoNODONTS. a, Prioniodus abbreviatus^ X ^4 '■> ''^ P' clavatus, X ^4 \ 

 c, P. erraticus, X ^4> ^y ^i Drepanodus arcuatus, X 7 > /» ^j Prioniodus armatus, 

 X 14; h, P. angulatus, X I4- (After Hinde. ) 



Trails. 



XIV. Nereites Murchison. 



Long, convoluted trails, of two rows of equally oval or pointed 

 crenulations. Cambric. 



The following species have been described by Emmons from the 



Fig. 1538. CoNODONTS. a-c, Prioniodus radicans : a, reverse showing groove ; b^ 

 c, front views, X 7 ; ci, f. elcgans, X 14- (After Hinde.) 



Taconic: 64, N. deweyi; 65, N. gracilis; 66, N. jacksoni; (fj, N. 

 lanceolatus; 68, N. loomisi; 69, N. pugnus; 70, N. robustus. (See 

 Taconic system, p. 69.) 



