482 Systematic Paleoxtology 



take a broad sweeping backward curve below the sutures; apical angle 

 fifteen to eighteen degrees." — Whitfield, 1893. 



Type Locality. — Lenola, New Jersey. 



Until the characters of the aperture are known the generic affinities 

 cannot be determined with any assurance. The single imperfect cast 

 from the area under discussion contributes nothing to the knowledge of 

 the form. 



The major axial nodes number ten to twelve to each of the later whorls. 



Occurrence. — Matawan Formation. Chesapeake and Delaware Canal 

 (exact locality not known). 



Collections. — Maryland Geological Survey, Philadelphia Academy of 

 Natural Sciences. 



Outside Distribution. — Matawan Formation. Merchantville clay 

 marl, New Jersey. 



Family VERMET1DAE 



Genus SERPULORBIS Sassi 

 [Giorn. Ligustica, vol. v, 1827, p. 482] 



Type. — Serpulorbis polyphragma Sassi = Serpula arcnaria Linne (ex 

 parte) = Vermetus gigas Gray. 



Tubes large, as a rule, and irregularly contorted; external surface 

 usually lirate and often more or less granulose; internal longitudinal 

 laminae not developed ; transverse partitions or pouches frequently present ; 

 non-operculate. 



The recent species occur in considerable numbers in the warmer waters. 



? Serpulorbis marylandica n. sp. 

 Plate XVII, Figs. 8, 9 



Description. — Type of two component tubes equal in size and increasing 

 in diameter with equal rapidity ; each surrounded by a discrete calcareous 

 layer, fused along the line of contact of the tubes into a single shelly 

 covering ; tubes performing about one and a half volutions, superimposed 

 one above the other at the beginning of the coil, but tending toward a 



Etymology: serpula, a little serpent; orbis, a circle. 



