298 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 53 



[pi. 30, fig. 11] is not found in Callavia or Holniia. V/aivicria aho 

 differs from Holinia in the character of the lateral extensions of the 

 pleurse. In Hohnia the spinose extensions give quite a different 

 aspect [pi. 2y, fig. 7] from that of the extensions of Waiincria [pi. 

 30, fig. i]. Wanncria differs from EUiptocephala [pi. 24, fig. i], 

 Mesonacis [pi. 26, fig. i], Nez'adia [pi. 23, fig. i], in the characters 

 of the thorax to such an extent that a statement of the differences 

 is unnecessary in this place. 



WANNERIA ? GRACILE, new species 



Plate 38, Figs. 15-24 



Hohnia rozvci Walcott, 1908, Smithsonian Misc. Coll., Vol. 53, No. 5. pp. 



187 and 188. (The specimens listed under this name in 3d of the 



Waucoba section are referred in this paper to JVanneria gracilc.) 

 Hohnia weeksi Walcott, iqo8. Idem, p. 189. (The specimens listed under 



this name in 3 of the Barrel Spring section are referred in this paper to 



JVanneria gracile.) 



Cephalon semicircular in outline, moderately convex ; marginal 

 border rounded, strong in the larger, narrow and wire-like in the 

 smaller specimens, and continued backward at the genal angles into 

 moderately strong spines ; posterior marginal border rounded and 

 narrow at the occipital ring and slightly broader where it merges 

 into the strong outer rim at the genal angles. In a cephalon 17 mm. 

 in length there are no traces of an intergenal angle [fig. 21], but 

 in one 7 mm. in length a broad angle is present and the marginal 

 rim is thickened by an oblique, obscure intergenal ridge that was 

 undoubtedly an intergenal spine in younger specimens [fig. 22], 

 An unusual specimen of the cephalon, 8 mm. in length [fig. 23], has 

 the outer margin curved inward very much as in a very young 

 cephalon 2 mm. in length [fig. 24] ; the ridge on the test from the 

 base of the eye out to the margin indicates the position of the inter- 

 genal spine at .r; the genal spine is not shown on the specimen. Gla- 

 bella convex, elongate, narrowing gradually from the occipital ring to 

 the front of the first lobe ; four strong furrows extend obliquely back- 

 ward from each side nearly to the center where they are united by 

 a very shallow transverse furrow ; the very slight dorsal furrow about 

 the glabella is crossed by the occular ridges that join the anterior 

 lobe of the glabella at its postero-lateral margins ; the second, third, 

 and fourth glabellar lobes are curved slightly backward and almost 

 pass into the flat area within the palpebral lobe ; the proportions of 

 all the glabellar lobes and the occi]iital ring are shown by figs, ig 



