( 37 ) 



DIYISON XXVI. SUBREGUL A.RES . 



GENERA. 



!. DentAlium. Lin. M. 



Tube almost regular, 

 slightly curved, insensibly 

 attenuated at the posterior 

 end, open at each extre- 

 mity. Fig. 134. 



ct. Tubes with ribs or longitudin al striae. 

 jS. . . perfectly smooth and simple . (1) 



2. Pectinaria. Lam. M. 



Tube membranous, like 

 a reversed cone. Fig. 135. 



3. Sabellaria, Lam. M. 



(2) 



- Tubes numerous, uni- 

 ted in a common mass, 

 alveolar above, composed 

 of grains of sand and 

 fragments of shells ; ori- 

 fices of tubes hollowed 

 like cups. 



4. Terebella. Cuv. M. 



Tube long, cylindrical, 

 attenuated and pointed at 

 the base, membranous. 

 (3) Fig. 138. 



5. Amphitrite. Brug. M. 



Tube long, cylindrical, 

 narrowing at base, mem- 

 branous or coriaceous, 



fenerally naked. (4) Fig. 

 36. 



(1) Foss. in London Clay, Crag Marl, Chalk Marl, Green Sand, Blue Marl, at 

 Grignon, Sarihe, Plaisantin, Sienna, Piedmont, Dax, Mons. 



(2) European Seas. 



(3) There is one species found on the European coasts, very remarkable from the 

 appearance of its tubes, which are formed of large fragments of shells ; and the 

 openings of the edges are prolonged into several branches, formed of the same 

 materials : they are chiefly from Norway, Holland, and Carolina. 



(4) European and American Seas. There is a large species in the Southern 

 Seas, the tube of which, thin and polished, appears to be transversely fibrous, 

 and to be formed of some soft filamentous substance dried. The tubes of another 

 species, when in a compact mass, are so symmetrically arranged that they appear 

 like honeycombs. They are generally very small, found affixed to Fuci, shells, 

 and other marine bodies, in great numbera on the same body, but always 

 isolated. 



