138 VERMES phylum hi 



Terehella Cuv. (Fig. 218, /). Cylindrical, elongate, more or' less bent 



Firi. 218. 



A, Scrpula Hmo,r Goldf. Middle Jnia; Franconia. /.', C, S. ijimlialU Scliloth. Upper Cretaceous: Baiiiie- 

 witz, near Dresden. D, t'!. roiivohUa, Qo\dt Middle Jura ; Stuilen, WurteniberK. E, S. socialis Goldf. Middle 

 Jura ; Lahr, Baden. F, Same, enlarged. G, S. septemsulcata Eeich. Upper Cretaceous ; Bannewitz. //, S. 

 (lt<ittilnriaT)efr.)sjiirularaha,m. Eocene; Monte Berici, near Vicenza. /, Te rrhrUa. lapUloides Mimster. Upper 

 Jura ; Streitberg, Franconia. 



tubes, composed of cemented grains of sand, fish-debris, or other adventitious 



particles. Lias to Recent. 



Spirorhis Daudin (3Iicroconchus Murch.) 

 (Fig. 219). Minute, snail-like or spirally 

 enrolled calcareous tubes, cemented by the 

 flattened under side. The spiral may be 

 either dextral or sinistral, and is usually 

 ornamented externally Avith concentric striae 

 or annulatious, sometimes with tubercles or 

 spines. Abundant in the Paleozoic forma- 

 tions from the Ordovician onward, and also 

 at the present day ; somewhat less common 

 in the Mesozoic and Cenozoic eras. Recent 

 species usually adherent on seaweeds. 



Fin. 21'.». 

 Spirorhis mnphalodef: (Goldfuss). Tubes 

 seated U|)()n a BrachioiJod shell (Schnchcrti'.lla 

 niiihrncnlniii). Devonian ; (iernlstcin, Eifel. 



The following genera are commonly 

 regarded as Annelids, but their systematic position is doubtful : 



