- P-92 - 



OHAoSATELLir^S ( OrvA.JSIIIIiLLA) -ZEITUS n. sp. 



Sov'ldis- martinioensis Gabb, 1875, Trans , Am. Philos, 3oc., new 

 !er., vol. 15, p. "52 (non cl 'Orbiprny, 1845). 



■Description .- '^hell small, sli.'rhtly inequilateral, obliqiielj- 

 rounded-tri angular , well inflated; posterior dorsal margin relative- 

 ly short, slightly concave, aiterior dorsal margin longer, slight- 

 ly convex, meeting the broadly arcuate ventral margin less abrupt- 

 ly; umbones full, acute, slightly opisthop-yrate; escu.tcheon slip-ht- 

 ly broader and shorter than the limule, both moderately im'oress- 

 ed; advilt shell sculptured with fifteen to eighteen prominent 

 evenly spaced rounded rugae, seuarated by narrower intersrjaces ; 

 hinge normal. 



Dimensions .- Lenrrth 2.8 mm.; alt., 2,6 mm.; semidiam. , .9 mm. 



^Remarks .- *his well-defined species is based on a number of 

 valves. It is characterized by the longer antero-dorsal mar-in 

 and the numerous, prominent, regular concentric rugae. In size 

 nnd eonvezity it resembles bowdpnensis, but the oi^.tline is diff- 

 erent and the sculpture more prominent and more regi-.lar. ^>. few 

 of *:he valves are slightly larger than the measured type. 



Dall has describe'' a very closely related form, from the i>aplin 

 and Vaccamaw, 2* dii-'olinian-.s (1) , but it is sm.aller, less iuflat- 



(l). Trans. 'Jarmer "^ree In.:. 3ci., Philadelphia, vol. '^ , -.it. 6, 

 np. 1478-1479, ol. 50, f i rs . 5, 6, 190?. 



