- 
496 Lesquereux's Descriptions of 
69. Sricmaria umBonata (spec. nov.). Differs from Stig- 
maria ficoides by the scars, which are at least twice as broad, 
elevated, and with a single ring at the border. 
70. STIGMARIA IRREGULARIS (spec. nov.). Stem deeply 
and narrowly ribbed in its length ; scars distant and scarce, 
oval, sometimes acute at both ends, sometimes round, placed 
without order. 
71. Sriemarta Rrapicans (spec. nov.). Stem about two 
inches broad, narrowly striate in its length, scars irregular 
and irregularly placed ; rootlets apparently round and nar- 
rowed near the base. 
72. Sricmarta wrNUTA (spec. nov.). Stem thick, lower 
scars very small and close to each other, placed in a spiral or- 
der, round ; the superior ones more distant, oval, pointed or, 
open in their inferior part, central scars elongated, like a deep 
narrow line, dividing the general scars. 
Genus SIGILLARIA. 
73. SiGILLARIA SCULPTA (spec. nov.). Stem irregularly and 
narrowly striate in its length, without ribs; strie undulate; 
scars elevated, smooth, about an inch and a half distant, quad- 
rangular-rhomboidal oblique, emarginate, cordate above, with 
the three other angles acute ; vascular scars three, the medial 
one oval, crosswise ; the lateral ones linear arched. : 
14. SicILLARIA FISSA (spec. nov.). Surface striate in its 
length by narrow, undulate, smooth lines ; without ribs; scars 
about one inch distant, cordate, obtuse in outline, deeply 
emarginate above, round obtuse below, with two acute angles 
at both sides, and a single oval, vascular scar, attached in the 
middle of a semilunar or arched ring. 
15. SiGILLARIA DILATATA (spec. nov.). Surface marked 
with undulate, smooth, very narrow strie without ribs; — 
one eighth of an inch distant, plane, enlarged on the sides, 
being nearly twice as broad as high; emarginate, cordate 
above, very obtuse below ; lateral augles very acute ; vascular 
scars three, the medial one broadly oval, crosswise; the 1af- 
