extending to the tip; the margin between each tooth 
bisinuate and forming an obtuse lobule giving the corolla 
the appearance of being 10-angled; the five stamens free, 
epipetalous, attachedjto the corolla tube at approximately 
the same level, about 2.5—38 cm. from the base; filaments 
glabrous, 2-2.3 cm. long; style equalling or slightly ex- 
ceeding the anthers, 4.6-5.7 cm. long; young ovary cov- 
ered with spine-like hairs; calyx circumscissile, shed with 
the corolla, the persistent base expanding into a mem- 
branous disk-like structure subtending the capsule, 1.5-2 
em. in diameter on mature fruit; capsule globose, pubes- 
cent, pendent on 1.5-2 cm. long pedicels; irregularly 
dehiscent, covered with semicapillaceous pubescent bris- 
tles, up to 2.4 em. long; seeds reniform, about 5 mm. 
long and 3.5 mm. wide, seed coat verrucose. 
Mexico: State of Mexico, Dist. of Tamascaltepec, Bejucos, ““Ilano,”’ 
Aug. 15, 1935, G. B. Hinton et al 8173 (Tyrer in US 1841574).—State 
of Guerrero, Dist. of Coyuca, Pungarabato, ‘‘roadside,’’ July 9, 1935, 
G. B. Hinton et al 8030 (F, MO, US): Rio Balsas, Aug. 26, 1910, 
C. R. Orcutt 4384 (F).—State of Michoacan, Municipality of Apatzin- 
gan, ‘open sun-baked pasture one-half mile S. of Apatzingan, thick 
adobe soil, alt. 1200 ft.’’, July 31, 1940, W.C. Leavenworth 409 F, 
GH, MO, NY); Municipality of Apatzingan, “‘common between 
thorn forest and road, between Apatzingan and La Majada, alt. 1200 
ft.°’, Aug. 16, 1941, W.C. Leavenworth & H. Hoogstraal 1615 (F, 
GH, MO, NY). 
This species is known only from the Rio Balsas valley 
in Mexico. According to Leopold (1950), this valley is 
a tropical inland basin, cut off from the sea by highlands 
on all sides. In this basin, one encounters a nearly insular 
type of endemism, and an appreciable number of new 
species have been described from the collections of Hin- 
ton and Leavenworth from this general vicinity. This 
new Datura was collected by Leavenworth in the vicin- 
ity of Apatzingan at an altitude of 1200 feet and in an 
area designated by him as open, arid, scrub forest, which 
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