PYRICYTHEREIS [Cythereis?israelskyi Howe and Pyeatt, in 
Howe and Chambers 1935,p.33, pl.l,f.19-2l;pl.4, 
f.7-9] Howe, in Howe and Law 1936, p.65 [= Butonia 
Howe, by Howe 1947,pe50, and by Stephenson 1947, 
pe579) Eocene, Louisiana. 
PYROCYPRIS [6 species, the first P. chierchiae] G. W. Muller 
1890a, pe230-232 [Cypridinidae by G. We. Miller; = 
Cypridina (Cypridina) by Skogsberg 1920,p.313- 
317) Recent, Arabian sea. 
PYXION [Primitia carinata Hadding 1913,p.68,pl.6,f.12] 
Thorslund 1948,p.367 [Family not given by Thorslund; 
Beyrichiacea of unknown family by Henningsmoen 
1953,pe274] Ordovician, Sweden. 
PYXIPRIMITIA [P. ventriclefta] Swartz 1936,p.568 [Primitiidae 
by Swartz; Drepanellidae-Ulrichiinae by Schmidt 
1941,pe51; Beyrichiacea of uncertain family by 
Henningsmoen 1953, pe229,261,275] Devonian, Penn- 
sylvania. 
Q 
QUADRACYTHERE [Cythere truncula Brady 1898,p.e44h4,ple47, 
f.16,17] Hornibrook 1952,pe43 [Cytheridae-- 
Trachyleberinae by Hornibrook] Recent, New Zealand. 
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