Maryland Geological Survey 213 



Genus MERISTELLA Hall 



Meristella (?) sp. 

 Plate XXI, Figs. 3, 4 



Description. — Shell ovoid, minute. Ventral valve very gibbous in the 

 umbonal region and along the median line to its front but sloping steeply 

 from this line toward the lateral margins. No evidence of punctate struc- 

 ture and surface smooth with the exception of fine concentric lines and 

 perhaps very fine radiating striae. Dorsal valve ( ?) (associated with the 

 gibbous valve are a number of smaller ones, differently marked which 

 perhaps are dorsal valves of this species), with clearly marked concentric 

 lines of growth, four or five rather indistinct folds and very fine radiating 

 striae. 



Tliis minute shell was doubtfully referred to the genus Meristella by 

 the writer in the preliminary identification and further study has failed 

 in locating it more accurately. He has also availed himself of the kind- 

 ness of Prof. Schuchert and Doctors J. M. Clarke and Grabau — to secure 

 their opinions, given below, regarding the systematic position of these 

 specimens. " I should say that these specimens are of the genus Meristella. 

 There is no punctate shell and tlierefore not a Centronella. I don't know 

 this shell." Schucliert. " Yalve looks like Centronella. Shell texture 

 does not agree therewith. T am not familiar with this shell. Might be 

 called Meristella provisionally." Clarke. " I have been trying to satisfy 

 myself that the small Brachiopod is a Meristella. I don't know what else 

 it can be unless it is a Centronella. It does not compare well with any 

 form I know — may it not be a young Centronella? " Grabau. 



Length, 3 mm. : M-idth, about 3 mm. 



Occurrence. — Eomney Formation, Marcellus Member. AV. Ya. 

 Cent. E. E. cut at 81st Bridge. Hamilton Member. West of iron 

 bridge over Town Creek northeast of Oldtown ( ?). 



Collection. — Maryland Geological Survey. 



