Maryland Geological Survey 343 



tion and slight constriction of tlie margin. Test thick, especially in the 

 dorsal region; surface marked by very fine concentric striae, which are 

 often crowded together on the basal and posterior portions of the shell, 

 forming irregular undulations of gro^vth; in some well-preserved speci- 

 mens the concentric striae are elevated into sharp lamellae. A specimen 

 of average size has apparently about the following dimensions : length, 33 

 mm. and height, 19 mm. 



The Maryland Collection contains a rather imperfect and worn speci- 

 men which is referred with some hesitation to this species. The length 

 in comparison with the height is less than that in normal specimens of P. 

 tenuistriata ; but it shows similar fine concentric striae with heavier lines 

 of growth toward the margin and the general appearance is quite near 

 that of the larger forms of this species. The specimen was examined by 

 Dr. Grabau who wrote as follows : " Agrees well with P. constricta in 

 anterior position of beak but does not agree absolutely with any of the 

 Xew York t}^es. Except for the less proportional length it would agree 

 fairly well Tvath P. temiistriata. Should be tempted to call it a short 

 variety of that species." 



Another specimen of what appears to be a large Palaeoneilo from Evitts 

 Creek is referred with doubt to this species. Dr. Grabau examined the 

 specimen and wrote " P. tenuistriata perhaps. It has outline more of 

 Elymella cf. nuculoides Hall and sulcus is weak, this may be due to pres- 

 sure however." It is to be remembered that Hall figured a specimen of 

 this species from " near Cumberland, Md./' and also reported it from 

 " Pattersons Creek, [W.] Va." ' 



Length of specimen from McCoys Ferry, 32 -j- mm. ; height, 23 mm. 



Length of specimen from Evitts Creek, 40 mm. ; height, 27 mm. 



Occurence.— RoMNEY Formation, Hamilton Member. McCoys 

 Ferry; southwest of McCoys Ferry; east bank Evitts Creek below Wolfe 

 Mill; B. & 0. E. R. cut at 21st Bridge; W. Va. side Potomac River about 

 3 miles south of Cumberland. 



Collection. — Maryland Geological Survey. 



^ Pal. N. Y., vol. V, pt. i, Lamellibranchiata ii, p. 336, and pi. xlix, explanation 

 figs. 12, 14. 



