252 



VERMES 



SUB-KINGDOM IV 



sub-classes are distinguished, Chaetopoda and Hirudinea. A further difference 

 is to be noticed in the locomotive organs, the Chaetopoda having bristle-bearing, 

 unjointed appendages (parapodia) on each ring of the body ; and the Hirudinea 

 having a terminal sucker. The latter group includes only the Leeches, which 

 are not known with certainty in the fossil state. 



It is only the one order of marine Worms (Polychaeta) belonging to the 

 sub-class Chaetopoda with which the palaeontologist is practically concerned ; 

 as the Earthworms arid their allies (Oligochaeta) are wholly unknown as fossils. 

 The marine Chaetopoda are divisible into two principal sections, known as the 

 Sedentary or Tubicolous Worms, and the Nereid or Errant Annelides. 



Sub-Order A. TUBICOLA. (Sedentaria.) 



Annelides with indistinctly separated head, and short, usually 

 non - protrusible proboscis, without jaws. Parapodia short, and never used for 



FIG. 403. 



A, Serpula Umax, Goldf. Middle Jura ; Franconia. B, C, S. gordialis, Schloth. Upper Cretaceous : Banne- 

 witz, near Dresden. D, S. convoluta, Goldf. Middle Jura; Stuif'en, Wurtemberg. E, S. socialis, Goldf. Middle 

 Jura ; Lahr, Baden. F, Same, enlarged. G, S. septemsulcata, Reich. Upper Cretaceous ; Bannewitz. H, S. 

 (Rotularia, Defr.) spirulaea, Lain. Eocene ; Monte Berici, near Vicenza. /, Terebella lapilloides, Miinst. Upper 

 Jura ; Streitberg, Franconia. 



swimming. Inhabiting more or less firm tubes, which they construct for themselves, 

 and subsisting upon vegetable matter. 



The Tubicolous Annelides invest themselves with a protective tube of 

 usually irregular form, to which they are not organically connected, and in 



