I'LUIJA Ol- THE KUUTAM1-: 1-Uit.MA llU.N. 2U7 



of tlio ordinaiy small pinnulos of this spociiiKMi appear to he (juite coarso 

 and interrupted in length, which makes the j)ai'ls \isil)le look like the lineai' 

 sori of an Asplenium; otherwise their plan, and that of the nerves of the 

 basal pinnules, are the same as tliat of the norinal |)iruiules. 



In Mr. W Ced's collect ion fi-oni I he ( Ira ft on beds .a specimen of a small 

 fern reseml)lin<i .\crosticliites was .seen and reii'arded as a new species. 

 Xo name was proposed for it in the preliminary I'eport, liut it was com- 

 pai'ed with I)imkei'"s ANCalden species Pccoplcris (Iviiiilzii. 'Hie many 

 specimens of it occuirint!; in Professoi- NN'ard's collection show that this is 

 Cladophlebis heteropliijlld. This ,sj)ecimen is i'(>presented in PI. LXXI, 

 Fig. 25. 



Ci.AnDi'in.F.ius coxsTRi<r.\ Fontaine. 



I'l. i.XXI, Fi,>:. ■_'(). 



ISSO. Cladophlebis coiiNtricfd Font.: Potoinac l'"li>i-)i (M(in(i,t,^r. V . S. (iool. Siirv., 

 Vol. XV), |). (is, |il. ii. Ii<:s. II, 11a, 111): pi. iii, lii;. 2: vi, li>i;s. .5, rrn. 6, 6a, 

 N. Sa, '.). '.la, 111, 11. 1 la. I lli. I li 11; pi. \xi, lij^s. '.». 1 Ii : |)l. clxix, li<);s. 2, 'in. 



One imj)i'int of a fei-n with its reverse wa.s found in the Geyser beds 

 tli.al is stiikingly like Cladophlebis amHlncta Font., of the Lower Potomac 

 strata of Virginia. The i(l(Mitification of this fern with the Potomac form 

 is made questionable solely because the amount of material is not sufficient 

 to permit positive conclusions, and not because this specimen is unlike^ in 

 any respect that of Cladophlebis. In fact, the imprint is exactly like the 

 form depicted in Monograph, ITnited States Geological Survey, Vol. XV, 

 pi. ii, fig. 1 1 (not 12, as wrongly given in that work). The description of 

 this species gi\-(Mi on page 68 of the same work applies equally well to the 

 specimen now in question. The Geyser specimen corresponds to the 

 upper pimia? of the Potomac form gi\en in the figure quoted. The pin- 

 nules, however, ai-e rather smaller. 



The Geyser specimen is the imprint of an ultimate pinna, probably 

 from high up on the frond, which carries several pinnules. These are 

 remotely placed, mostly with undidate margins, but with soni(> having a 

 rounded shallow lobe on (>acli side at the base. The pinnules are rounded 

 off and constricted at base, and in shape are ovate, sometimes elliptical and 

 (n-(Mi hastate. They ai'e thick and leathery, with obtuse to subacute tips. 

 Th(> nervation is of Gladophlebis type. The lateral nerves are quite coar.se, 

 but rather vaguely defined. The upper ones are once or twice forked, the 



