DESCKIPTION OF THE SI'ECIES. 143 



TlIYRSOPTERIS OliTUSILOBA, SJ). UOV 

 riate LVIII, Figs. 7, 10. 



Frond tripiniiatiCul ; piniKv^ of ultimate order and ])innules subopposite, 

 remotely placed, short ; pinnules narrowly oljlong, obtuse, passing above 

 into entire ones, lower ones cut to varying depths into oblong, very obtuse 

 lobes ; lateral nerves very strong, in the lower lobes given off pinnately 

 on each side of a midnerve which splits up at the sunnnit ; the lateral 

 nerves forked or simple, in the upper lobes flabellate and forking once or 

 twice. 



Localities: Red clay ball in the banks of Dutch Gap Canal; hill-side 

 near Potomac Run ; rare. 



This plant has the facies of a ClaclojMebis. It seems to be a distinct 

 new species. 



Thyrsopteris spnENOPTEROiDES, sp. nov. 



Plate LVIII, FiR. (i. 



Frond bipinnate or tripinnate ; ultimate piniui; winged; leaf-substance 

 thick; pinnules small, much narrowed at base, almost petioled, distant, 

 elliptical or subrhombic in shape, acute; lower ones cut into diverging 

 ovate-acute lobes, upper ones entire; nerves strong, composed in each pin- 

 nule of a midnerve which splits up towards the summit and sends off pin- 

 nately into the lobes and teeth lateral nerves which fork usually once. 



Locality: Hill-side near Potomac Run ; very rare. 



This seems to be nearly allied to no previously described species. 



Thyrsopteris squarrosa, sp. nov. 



Plate LIX, Fig. :i. 



Frond tripinnatifid ; primary rachis stout, somewhat flexuous ; ulti- 

 mate pinnag alternate, winged, closely placed ; pinnules crowded, much 

 narrowed at base, short in outline, triangular, cut more or less deeply into 

 lobes which spread widely from the midnerve, standing almost at right 

 angles with it, the lobes more or less club-shaped or spatulate in form, the 

 basal ones being obtusely three-lobed ; the pinnules are broadest at base, 

 and stand nearly at right angles with the niidrilt : nerves strong, com- 



