106 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 148 



characters of the species. The glabella shows 2 pairs of short, rather 

 shallow lateral furrows; those of the posterior pair show a tendency 

 to bifurcate. The occipital ring is rounded, lacking spine or node. The 

 frontal area is divided about equally into preglabellar field and border 

 by an excessively shallow furrow, which becomes obsolete medially. 

 The surface of the test is very finely granulate. Length of holotype 

 cranidium 2.2 mm., width at posterior end 3.3 mm. 



Occurrence. — Uppermost beds of the Maryville limestone (Cedaria 

 zone) at locality cnc/1. 



Types.— Holotype: U.S.N.M. 144712. Paratypes: U.S.N.M. 

 144713. 



Genus ITHYCEPHALUS Resser, 1939 



Type species. — Ithycephalus typicalis Resser. 



ITHYCEPHALUS TYPICALIS Resser 



Plate 1, figures 10-12 



Ithycephalus typicalis Resser, 1938a, p. 82, pi. 9, fig. 10. 



A perfect cranidium of this rare species is figured. 



Occurrence. — Type locality U.S.N.M. 27d ; red beds at the base of 

 the Nolichucky {Cedaria zone) east of Rogersville. The figured speci- 

 men is from the same beds and locality (author's locality cnd/1). One 

 specimen was also collected from the underlying uppermost beds of 

 the Maryville limestone (loc. cnc/1). 



Ty/'^.?.— Holotype : U.S.N.M. 94841. Plesiotype: U.S.N.M. 

 144714. 



Genus MODOCIA Walcott, 1924 



Type species. — Arionellus (Crepicephalus) oweni Meek and Hay- 

 den. 



Three genera have been considered synonyms of Modocia: Armonia 

 Walcott, 1924 (type species, Armonia pelops Walcott) ; Metisia 

 Resser, 1937 (type species, Ptychoparia metisensis Walcott) ; and 

 Semnocephalus Resser, 1942 (type species, Solenopleura? weedi 

 Walcott (part) ) . 



A question arises concerning the status of the genus Syspacheilus 

 Resser, 1938 (type species, Syspacheilus typicalis Resser). Palmer 

 (1954) discussed the problem of assigning a pygidium to Syspacheilus. 

 He attributed to cranidia identified as Syspacheilus camurus Lochman 

 pygidia indistinguishable from Coosella. Lochman and Hu (1961) 

 attributed to 6". dunoirensis (Miller) and a new species, Syspacheilus 

 praecedens, short pygidia of the generalized ptychoparioid type. 



The latter assignment seems unquestionable, in view of the abun- 



