41S Systematic Paleontology 



TUBKIS SEDESCLAEA n. Sp. 



Plate XIV, Figs. 1, 2 



Description. — Shell large for the genus, fusiform in outline; apex of 

 spire broken away and nuclear characters lost; whorls probably eight to 

 ten in number ; external sculpture clominantly axial ; costals well rounded, 

 abruptly elevated, somewhat irregular in size and spacing and tending to 

 evanesce toward the aperture ; nine in number upon the penultima, uni- 

 form in promineDce from their initiation at the fasciole to the anterior 

 suture; spiral sculpture of very faint and fine lirations which do not 

 override the costals, approximately twenty in number on the penultima 

 in front of the fasciole and eight less feeble striae upon the fasciole; 

 fasciole about one-fourth the width of the whorl, differentiated by a 

 shallow sulcus and by the absence of any axials other than irregular growth 

 sculpture; spiral sculpture upon the body whorl becoming increasingly 

 coarser and more distant anteriorly ; body whorl well rounded, not sharply 

 constricted at the base; outer lip imperfect, broadly arcuate; inner lip 

 smoothly concave; pillar straight and probably quite long (imperfect in 

 the type) ; siphonal notch apparently very shallow and placed in front of 

 the fasciole. 



Dimensions (imperfect individual). — Altitude 37 mm., maximum 

 diameter 19.5 mm. 



This species is characterized by its rather large size, coarse and not very 

 regular axial sculpture, and very fine and crowded spiral threading. 



Occurrence. — Monmouth Foemation. Brightseat, Prince George's 

 County. 



Collection. — Maryland Geological Survey. 



Tuebis monmouthensis n. sp. 

 Plate XIV, Pigs. 3, 4 

 Description.' — Shell rather slender, fusiform in outline, the maximum 

 diameter in front of the median horizontal ; spire much elevated, its sides 

 flattened and converging at an angle of approximately 25° ; whorls prob- 

 ably seven or eight in all ; apex broken away so that exact number is inde- 



