NEW AMERICAN PALEOZOIC^ OSTRA(X)DA. 



NOTES AND DESCRIPTIONS OF UPPER CARBONIFEROUS 

 GENERA AND SPi:ClES. 



By Edwaki) O. Ulkich," 



Geologht, U. S. Geological Survey, 



And Rav S. Bas8Lek, 



As.vstrcnl Curator, fh'partnient of Gmlogi/. 



The first article of this series of papers was published l)y Mr. Ulrich 

 in 1900/' wheM species of Ctefwhollr/mt and /ur/thi/a wovo, described. 

 Since that time Mi-. Bassler has joined Mr. Uh-icli in the study of 

 these organisms and they now hope to publish papei-s upon this sub- 

 ject more frequently. Their aim in these papers will be to publish 

 illustrations and descriptions of new families, genera and species, as 

 well as notes upon those already establishinl, leaving the classification 

 and definition of the higher groups until a future time, when the fossil 

 ostracoda can be made the subject of a monograph. All of the speci- 

 mens figured in this article are in the collections of th(^, United States 

 National Museum. 



Superorder OSTRACODA. 



Family LEPERDITELLID.I^:, new family. 



Genus PARAPARCH ITES, new genus. 



Leperditia (part) of authorH. 



Carapace small, 1 mm. to 2 mm. in length, lepcu-ditoid or subovate 

 in shape; surface smooth, sometimes with a small tubercle or spine in 

 antero-cardinal third of each valve; right valve with ventral edge rab- 

 beted so as to slightly overlap the simply beveled edge of the left 

 valve; dorsal edges of valves usually unequal, the left slightly the 



"Published by permission of the Director of the U. H. < jeolof^ical Survey. 

 Mour. Cincinnati S(^. Nat. Hist., XIX, 1900, pp. 179-185. 



Proceedings U. S. National Museum, Vol. XXX— No. 1446. 



149 



