59 Olsson, Neocene Fossils 21 



Glottidia inexpectans, n. sp., Plate 5, Fig's 17-21 



Shell linguloid ; elongated with the anterior extremity trun- 

 cated ; beaks obtuse and rounded at first, later becoming acute ; 

 lime depositing regularly throughout ; surface polished, with dis- 

 tant marks of resting stages parallel to growth lines ; other 



growth lines indistinct ; sides of young shell nearly parallel or 

 slightly wider in the middle ; no punctate structure visible with 



high power'; cardinal area in young shells distinct but small, 

 grooved, not seen in older shells on account of their fragmentary 

 nature ; ventral valve with two nearly straight laminae, which di- 

 verge at a small angle ; dorsal valve with a straight medial sep 



turn which does not quite reach to the posterior valve margin ; 



no muscle scar visible in the adult shells ; valve of young shell 

 with the umbonal scar represented by a single, slight depression 

 just in front of the beak; laterals by two scars separated by a short 

 medial septum, and just in front of the umbonal scar ; color of 

 shell, which appears to be original, cream-white, yellowish brown 

 or blackish. 



Length y.o, width 4. .5 mm.( vent, valve, fragment} 

 Length 4. .5 , width 5.5 mm . ( dorsal valve) 

 Length 10, width 5.5 mm. {large fragme7ii) 



The occurrence of this brachiopod in the Miocene is of more 

 than usual interest as seeming to represent the sole example of the 

 genus Glottidia in a fossil state. The above description is based 

 on fragments of several adult individuals and upon a score or 

 more young shells, generally under 5 mm. in length. The young 

 shells were all found together in the sand contained in the closed 

 valves of a large specimen of Pecten s jejfersoniiis. They were ac- 

 companied by Modiolus pulchellus, Diplodonta yorke7isis and : ea- 

 urchin spines, probably belonging to Echinocardium orthonotum. 

 This species is very distinct from the common Atlantic Glottidia 

 audebarti Broderip (G. pyra?tiidata Stm. ) and shows much closer 

 relationship with the Pacific G. albida Hinds. From G. audebarti 

 the Miocene shell differs in having the lime secreted evenly 

 through the shell, and in having the laminse of the ventral valve 

 nearly straight and diverging at but a small angle. G. a/lida of 

 the Pacific has more pointed beaks and a more ventricose shell, 

 due to the three elevated ridges which radiate from the beaks. 

 Yorktown formation ; Kingsmill on the fames river 



