9 Agno. 



Agnostus similis. See Agnostus acadicus. L. C. 



Agnostus ? reported by Prof. H. D. Rogers as found, 



with IlemiGrypterus^ and a small branching fucoid, in F, Clin- 

 ton lower calcareous shale, 5 m. below Jersey Shore, in Ly- 

 coming county, Pa. Geol. Pa. 1858, Vol. 1, page 536 ; quoted 

 also in Report T, page 43. 



Agraulos quadrangularis. {Arionellus quadrangularis,) 

 LC »' rt 7 W^l^^^^^ Bulletin No. 10, U. S. G. S. page 

 ^^Ib.* ^^' pl?ie 7, fig. 1 ; a head exclusive of the 



free cheeks, and of natural size, in Prof. 

 Shaler's collection. (A smaller spec, in 

 Mus. Post. S. N. H. shows a small spine. 

 See Ordway, Proc. B. S. N. H. VIII, 6, 1861.) 

 L. C. Lower Cambrian (Braintree argillite) formation, S. 

 Brain tree, Mass., with Paradoxides harlanL 



Alectorurus cincinnaticus. See Spirophyton cincinnati- 

 cum. /// h. 



Alethopteris^ a genus of carboniferous ferns of many de- 

 scribed European and American species. See Report P, on 

 the Coal Flora of Pennsylvania, and the U. S. by Leo Lesquereux. 

 Of the latter are : A, ambigua^ from Pennsylvania ; hunhuryi^ 

 from Ohio; GOxana.lLeiiinQkj \ distans^Fa.] /alcata^ III. \ gib- 

 soni^Fa.; grandifolia^ Ohio; grandis^'i^.S.] halU^Ill,'; helence. 

 Pa.; holdeni^ Ohio \ hymenophylloides.^ 111. \ in/lata^ III.] Icevis^ 

 Pa. ; lanceolata^ 111. ; lonchitica^^ Pa. ; macrophylla^ Ohio ; 7nas- 

 sillonis^ 111.; maxima^ Ohio; mazonana., 111.; ohscura.^ Pa.; 

 oweni., Arkansas ; pectinata, 111. ; pennsylvanica. Pa. ; phicken- 

 eti., Pa. and Europe ; rugosa. Pa. ; serlii^ Pa. and Europe ; ser- 

 rula, Pa. ; solida^ 111. ; spinulosa^ 111. ; stellata^ 111. ; all found 

 in the roof shales of coal beds. Alethopteris Virginia lived late 



in the Carboniferous Permian age. S. W. Pa. and W. Va. ; dis- 

 Gvepans., ingens^ perleyi^ are species found by Dawson in the 

 much' earlier Devonian rocks of Nova Scotia. Alethopteris^ 

 specimen 3126, Rept-. O, with sphenoptoris cristata^ came from 

 the Bond vein mine, Alton, McKean Co., Fa., belonging in the 

 Mercer group between the Upper and Middle Conglomerates, 

 XII G^ XII b. Alethopteris extraordinarily abundant in roof of 



