1	Trees or shrubs; calyx leathery; stems and leaves often stellate hairy when young.		(2)
+	Herbs, sometimes woody at base; calyx herbaceous or membranous; stems and leaves without stellate hairs.		(4)
2 (1)	Corolla tube long, both lips equal in length		3 Paulownia
+	Corolla tube short, upper lip much longer than lower.		(3)
3 (2)	Capsule septicidal; calyx irregularly 3- or 4-lobed		4 Wightia
+	Capsule loculicidal; calyx regularly 2- or 5-lobed		2 Brandisia
4 (1)	Leaves abaxially glandular punctate.		(5)
+	Leaves not glandular punctate.		(7)
5 (4)	Aquatic or marsh herbs		15 Limnophila
+	Terrestrial herbs.		(6)
6 (5)	Corolla tube inconspicuous; stamens subequal		8 Scoparia
+	Corolla tubular; stamens didynamous		14 Adenosma
7 (4)	Corolla base spurred, lower lip convex and dilated toward upper lip in center, almost sealing throat, making corolla personate		27 Linaria
+	Corolla neither spurred nor personate.		(8)
8 (7)	Fruit berrylike.		(9)
+	Fruit capsular or drupaceous (Lagotis).		(10)
9 (8)	Leaves uniform; fruit indehiscent		16 Lancea
+	Leaves dimorphic; fruit dehiscent		32 Hemiphragma
10 (8)	Plants much branched, diffusely cushionlike; leaves less than 5 mm		25 Microcarpaea
+	Plants erect to creeping, never cushionlike; leaves usually longer than 5 mm.		(11)
11 (10)	Plants sometimes floating; stolons creeping; leaves and flowers in a basal tuft		26 Limosella
+	Plants aquatic or terrestrial, never floating; stems creeping and also erect; leaves and flowers never in a basal tuft.		(12)
12 (11)	Sepals free, 4 or 5, imbricate, unequal in width.		(13)
+	Sepals connate to almost free, not imbricate at least after flowering, equal in width.		(14)
13 (12)	Outermost sepals not cordate; anther locules parallel; stigma dilated, capitate, or 2-lobed; capsule loculicidal or 4-valved		9 Bacopa
+	Outermost sepals cordate; anther locules divaricate; stigma 2-lamellate; capsule septicidal		17 Picria
14 (12)	Pedicel coiling after flowering; seeds densely peltate hairy		33 Ellisiophyllum
+	Pedicel not coiling after flowering; seeds glabrous.		(15)
15 (14)	Staminode 1, in center of corolla upper lip; anther locules confluent, reniform and transverse; filaments apically dilated.		(16)
+	Staminodes 2 if present, anterior; anthers not transverse (except in some Gratiola and Verbascum); filaments not dilated.		(18)
16 (15)	Plants more than 10 cm tall; flowers in cymes, rarely axillary, never fascicled; pedicel conspicuous; corolla tube short and thick		5 Scrophularia
+	Plants less than 10 cm tall; flowers solitary or fascicled in axils; pedicel inconspicuous; corolla tube elongated.		(17)
17 (16)	Flowers in fascicles; corolla conspicuously 2-lipped; petiole short		6 Oreosolen
+	Flowers solitary; corolla obscurely 2-lipped, subactinomorphic; petiole ca. 2 X as long as leaf blade		7 Nathaliella
18 (15)	Corolla rotate, almost without a tube.		(19)
+	Corolla not rotate, if sometimes subrotate then stamens only 2 and tube conspicuous.		(20)
19 (18)	Leaves alternate; flowers 5-merous; filaments woolly		1 Verbascum
+	Leaves opposite or whorled; corolla 4-merous; filaments glabrous		38 Veronica
20 (18)	Stamens 2, staminodes absent; corolla (3 or)4-lobed, actinomorphic or slightly zygomorphic, if 2-lipped, then lower lip often 1- or 2-lobed.		(21)
+	Stamens 4 or if 2, then 2 staminodes present abaxially; corolla conspicuously 2-lipped, lower lip 3-lobed, upper 2-lobed or entire, or 5-lobed and subactinomorphic (corolla 4-lobed in Neopicrorhiza but then basal leaves rosulate).		(25)
21 (20)	Calyx parted to base on lower side, spathelike or sometimes also 2-lobed adaxially; leaves mostly basal; fruit drupaceous, indehiscent		39 Lagotis
+	Calyx 4- or 5-lobed; leaves on stem; fruit a capsule.		(22)
22 (21)	Calyx lobes 5, subequal in length; stamens exserted; stigma small, weakly dilated		35 Veronicastrum
+	Calyx lobes 4 or if 5 then upper one much smaller than other lobes; stamens included in corolla; stigma capitate or clavate.		(23)
23 (22)	Corolla limb conspicuously 2-lipped with strongly reflexed lower lip, tube conspicuous; leaves alternate		36 Scrofella
+	Corolla limb weakly 2-lipped, often subrotate, tube usually weakly developed; leaves opposite, whorled, or alternate.		(24)
24 (23)	Racemes terminal, long and densely spicate; bracts small and narrow; capsule subglobose, slightly compressed; corolla with conspicuous tube and slightly 2-lipped limb; stems mostly more than 30 cm tall		37 Pseudolysimachion
+	Racemes axillary or terminal, usually short and lax, if raceme terminal then lower bracts similar to leaves; capsule usually strongly compressed; corolla mostly with short tube and subrotate limb; stems mostly less than 25 cm tall		38 Veronica
25 (20)	Leaves basal and rosulate; rhizomes stout; inflorescences spicate		34 Neopicrorhiza
+	Leaves on stems and also basal (Triaenophora scapose but leaves very large); rhizomes slender if present; inflorescences mostly racemose.		(26)
26 (25)	Upper corolla lip galeate or rostrate; anther locules mucronate or base spurred.		(27)
+	Upper corolla lip straight or revolute, never galeate; anther locules rarely mucronate, base often obtuse.		(41)
27 (26)	Leaves alternate; upper corolla lip rostrate, conspicuously longer than lower lip; anther locules unequal in length or free, or anthers 1-loculed.		(28)
+	Leaves opposite; upper corolla lip galeate, as long as lower lip; anther locules equal in length, connivent.		(29)
28 (27)	Anther locules 2, unequal in length; calyx unequally 4-lobed, parted to middle medianly, more shallowly laterally; corolla lower lip lobes patent		47 Castilleja
+	Anther essentially 1-loculed; calyx subequally 4-lobed; corolla lower lip shallowly saccate		48 Triphysaria
29 (27)	Calyx upper side parted to middle, lower side and laterally shallowly parted, strongly inflated and utriculate in fruit; seeds compressed, often winged; branches and leaves subappressed to main stem		55 Rhinanthus
+	Calyx equally parted or more deeply parted medianly, not inflated in fruit; seeds not compressed; branches and leaves spreading.		(30)
30 (29)	Capsule 1-4-seeded; seeds large and smooth; bracts dentate to setose dentate, rarely entire; upper corolla lip densely bearded at margin		49 Melampyrum
+	Capsule with numerous seeds; seeds small and sculptured; bracts often entire; upper corolla lip not bearded at margin.		(31)
31 (30)	Bracteoles 2 below calyx.		(32)
+	Bracteoles absent.		(35)
32 (31)	Basal leaves well developed.		(33)
+	Basal leaves scalelike.		(34)
33 (32)	Calyx ovoid, conspicuously 5-ribbed; leaves entire or dentate; stems often winged, rarely terete		58 Pterygiella
+	Calyx tubular, conspicuously 10-ribbed; leaves pinnatifid; stems terete		59 Siphonostegia
34 (32)	Capsule regularly loculicidally dehiscent; sinuses between calyx lobes often 1-3-toothed; corolla yellow, more than 2.5 cm		60 Cymbaria
+	Capsule loculicidally dehiscent on 1 side (only 1 locule dehiscent); sinuses between calyx lobes toothless; corolla pale purple or white, less than 2 cm		61 Monochasma
35 (31)	Calyx 4-lobed; capsule apex obtuse.		(36)
+	Calyx 5-lobed; capsule apex tapered or truncate.		(38)
36 (35)	Inflorescence a racemose panicle		52 Omphalotrix
+	Inflorescence a spike.		(37)
37 (36)	Bracts often larger than leaves; margin of upper corolla lip revolute		51 Euphrasia
+	Bracts smaller than leaves; margin of upper corolla lip straight		54 Odontites
38 (35)	Leaves palmatisect; capsule emarginate; upper corolla lip slightly arching forward, obscurely galeate, parted to middle		53 Pseudobartsia
+	Leaves pinnatisect, pinnatifid, or serrate; capsule apex tapered; upper corolla lip conspicuously galeate, entire or shallowly 2-lobed.		(39)
39 (38)	Calyx equally parted; leaves pinnatisect		50 Phtheirospermum
+	Calyx more deeply parted on lower side; leaves serrate, pinnatifid, or pinnatisect.		(40)
40 (39)	Calyx 5-lobed; corolla upper lip revolute, not extending into a beak; leaves serrate		56 Xizangia
+	Calyx 2-5-lobed; corolla upper lip galeate and often extending into a narrow beak; leaves pinnatifid to pinnatisect		57 Pedicularis
41 (26)	Bracteoles 2; corolla subactinomorphic or 2-lipped in Rehmannia and Gratiola.		(42)
+	Bracteoles absent; corolla conspicuously 2-lipped.		(49)
42 (41)	Corolla salverform; fertile anthers with 1 locule aborted.		(43)
+	Corolla not salverform; fertile anthers 2-loculed.		(44)
43 (42)	Corolla tube straight; inflorescences spicate, flowers crowded; lower leaves broad and dentate, upper narrow and entire; hemiparasitic		45 Buchnera
+	Corolla tube apically curved; inflorescences laxly spicate; all leaves narrow, entire, rarely dentate, sometimes reduced to scales; parasitic		46 Striga
44 (42)	Calyx spathelike, deeply parted on lower side, entire or 3-5-toothed		41 Centranthera
+	Calyx campanulate, equally 5-lobed.		(45)
45 (44)	Corolla (3.5-)5-7 cm; calyx 1.5-3 cm		30 Rehmannia
+	Corolla less than 1 cm; calyx less than 0.5 cm.		(46)
46 (45)	Fertile anthers 2.		(47)
+	Fertile anthers 4.		(48)
47 (46)	Plants less than 25 cm tall; anthers 2-loculed; flowers solitary in leaf axils		10 Gratiola
+	Plants more than 25 cm tall; anthers with 1 locule aborted; flowers in racemes		44 Sopubia
48 (46)	Calyx covering corolla tube, inflated after flowering; corolla subcampanulate; at least lower leaves opposite, 3-veined		42 Alectra
+	Calyx covering ca. 1/2 of corolla tube, not inflated; corolla tubular; leaves alternate, 1-veined		40 Petitmenginia
49 (41)	Calyx 3- or 5-winged or conspicuously 3- or 5-angular, toothed.		(50)
+	Calyx neither winged nor conspicuously angular, parted into 5 conspicuous lobes, lobes sometimes secondarily lobed.		(54)
50 (49)	Calyx broadly 3-winged, 3-toothed		18 Legazpia
+	Calyx 5-winged or 5-angled, 5-toothed.		(51)
51 (50)	Calyx not inflated in fruit, mouth not truncate; filaments often appendiculate.		(52)
+	Calyx inflated, bladderlike in fruit, mouth truncate or obliquely truncate; filaments not appendiculate.		(53)
52 (51)	Calyx 5-angular, actinomorphic; capsule septum persistent		19 Lindernia
+	Calyx 5-winged, rarely conspicuously 5-angular, 2-lipped; capsule septum not persistent		20 Torenia
53 (51)	Flowers solitary in leaf axils, ebracteate; slender and weak herbs		21 Mimulus
+	Flowers in cymes, usually bracteate; large and erect herbs, woody at base		22 Cyrtandromoea
54 (49)	Fertile stamens 2, staminodes 2; aquatic or marsh herbs.		(55)
+	Fertile stamens 4; terrestrial herbs (some species of Mimulicalyx and Lindernia aquatic or marsh herbs).		(57)
55 (54)	Leaves petiolate, dentate; capsule cylindric		19 Lindernia
+	Leaves sessile and entire; capsule ovoid-globose or globose.		(56)
56 (55)	Calyx parted to slightly beyond middle; stems succulent; filaments straight at apex; anthers glabrous		11 Dopatrium
+	Calyx parted almost to base; stems not succulent; filaments twisted; anthers hairy		12 Deinostema
57 (54)	Corolla more than 3 cm; petiole long; stem leaves alternate or absent.		(58)
+	Corolla less than 3 cm; petiole usually short; at least lower stem leaves opposite.		(60)
58 (57)	Leaves woolly; stem leaves absent; calyx 5-lobed, each lobe 3-parted and hastate		31 Triaenophora
+	Leaves glandular hairy; stem leaves present; calyx irregularly toothed or lobes entire.		(59)
59 (58)	Calyx tube present; corolla lips nearly equal in length		30 Rehmannia
+	Calyx parted almost to base; upper corolla lip short, middle lobe of lower lip longest		29 Digitalis
60 (57)	Stems scaly near base, much branched and broomlike; leaves few, sessile, linear or scalelike, alternate apically on stem; xerophytic		24 Dodartia
+	None with above combination of characters; mesophytic or helophytic.		(61)
61 (60)	Stems quadrangular; lower corolla lip outer in bud, enveloping upper one.		(62)
+	Stems terete (quadrangular in Mazus lanceifolius); upper corolla lip outer in bud, enveloping lower one.		(63)
62 (61)	Calyx 5-ribbed; seeds numerous		28 Mimulicalyx
+	Calyx 10-ribbed; seeds 2 per locule		43 Leptorhabdos
63 (61)	Calyx parted almost to base, sometimes less so; capsule often elongated; filaments often appendiculate		19 Lindernia
+	Calyx parted to about middle; capsule short; filaments not appendiculate.		(64)
64 (63)	Stems and leaves glandular hairy; stem leaves opposite; anther locules separated by a stalked connective		13 Lindenbergia
+	Stems and leaves glabrous or eglandular villous; basal leaves usually well developed, sometimes rosulate, upper stem leaves often alternate; anther locules apically connivent		23 Mazus