1	"Corolla 15--20 cm; calyx 8--12 cm, ribbed; seeds tan"	"Datura wrightii"
1	"Corolla 4.5--16 cm; calyx 2--9 cm, angled or winged; seeds black or gray-brown"	2
2	"Fruit nodding, prickles many, weak; stem gray-hairy"	"Datura discolor"
2	"Fruit erect, prickles few, stout; stem +- glabrous to sparsely hairy"	3
3	"Fruit prickles 8--22 mm; calyx 2--2.5 cm"	"Datura ferox"
3	"Fruit prickles 3--10 mm; calyx 3.5--4.5 cm"	"Datura stramonium"