Plante Lindheimeriane. É 205 
squamosis in axillis ex tomento albo brevissimo setas spines- 
centes albidas 3—5 gerentibus; sepalis interioribus 8 ovato- 
oblongis carinatis obtusis mucronatis; petalis 10 obovato- 
spathulatis obtusis integris concavis chartaceis (coccineis) ; 
stylo longe supra stamina numerosissima exserto; stigma- 
tibus 7 acutiusculis erecto-patulis viridibus. — Granitic re- 
gion about the Liano: flowers (in St. Louis) in May. — 
Named after my friend Dr. F. Roemer, of the University of 
Bonn, who was the first to explore the geology of Western 
Texas, and brought the first specimens of this species. Sent 
also in numerous specimens by Lindheimer. Heads 3-4 inches 
high, 1: — 21 inches in diameter, single, or mostly 3—5 or even 
10 from the same base; ribs interrupted: areole 4—8 lines 
distant from one ancien! radial spines 5—12 lines long ; lateral 
spines longest: upper ones usually shortest; central spine 10— 
15 lines long. Flower open by day and night, for 4 or 5, and 
in cool cloudy weather as much as 6 or 7 days, 2 inches long, 
and one wide: petals 8 — 9 lines long, 5 lines wide, stiff: bris- 
tles on the tube 2—3 lines long. — The stiff and almost per- 
gamentaceous petals are uninfluenced by sunshine or darkness 
like those of most other Cactacew. Several other northern 
species most probably agree in this particular, as especially 
C. coccineus and C. triglochidiatus of New Mexico; while 
other nearly related species have certainly diurnal flowers. — 
C. coccineus differs by the more numerous ribs, more numer- 
ous spines, larger and more crowded areole, etc. C. polyacan- 
thus, Engelm. in Wisliz. Rep., has more numerous spines, 
and ten ribs, C. enneacanthus, Engelm. 1. c., is larger with the 
tubercles less distinct, ten ribs; spines larger, angular. 
Cereus variasitis, Pfeiff., with its beautiful white noc- 
turnal flowers, delighted our volunteers in their camps on the 
lower Rio Grande. Young plants are procumbent, with 
terete or rather clavate branches: adult plants several (3— 
10) feet high, mostly triangular, with very long and stout, or 
sometimes quite short spines. Fruit large, luscious, with red 
pulp: seeds large, smooth, a 
JOURNAL B, S. N. H. JAN. 1850, 
