| 1 | 
|   | Species 
biennis
(Moench) Fern. common name: 
tall blue lettuce
 |  |  | 
| 2 | 
|   | Species 
campestris
Greene |  |  | 
|  | 
| 3 | 
|   | Varietas 
typica
Wieg. syn. Lactuca ludoviciana
 |  |  |  | 
| 4 | 
|   | Species 
canadensis
L. |  |  | 
|  | 
| 5 | 
|   | Varietas 
integrifolia
(Bigelow) Torr. & Gray syn. Lactuca canadensis
 |  |  |  
| 6 | 
|   | Varietas 
latifolia
Kuntze syn. Lactuca canadensis
 |  |  |  
| 7 | 
|   | Varietas 
longifolia
(Michx.) Farw. syn. Lactuca canadensis
 |  |  |  
| 8 | 
|   | Varietas 
obovata
Wieg. syn. Lactuca canadensis
 |  |  |  
| 9 | 
|   | Varietas 
typica
Wieg. syn. Lactuca canadensis
 |  |  |  | 
| 10 | 
|   | Species 
floridana
(L.) Gaertn. |  |  | 
|  | 
| 11 | 
|   | Varietas 
floridana common name: 
woodland lettuce
 |  |  |  
| 12 | 
|   | Varietas 
villosa
(Jacq.) Cronq. common name: 
woodland lettuce
 |  |  |  | 
| 13 | 
|   | Species 
graminifolia
Michx. |  |  | 
|  | 
| 14 | 
|   | Varietas 
arizonica
McVaugh common name: 
grassleaf lettuce
 |  |  |  
| 15 | 
|   | Varietas 
graminifolia common name: 
grassleaf lettuce
 |  |  |  | 
| 16 | 
|   | Species 
hirsuta
Muhl. ex Nutt. |  |  | 
|  | 
| 17 | 
|   | Varietas 
albiflora
(Torr. & Gray) Shinners common name: 
hairy lettuce
 |  |  |  
| 18 | 
|   | Varietas 
hirsuta common name: 
hairy lettuce
 |  |  |  
| 19 | 
|   | Varietas 
sanguinea
(Bigelow) Fern. common name: 
hairy lettuce
 |  |  |  | 
| 20 | 
|   | Species 
indica
L. common name: 
Indian lettuce
 |  |  | 
| 21 | 
|   | Species 
intybacea
Jacq. syn. Launaea intybacea
 |  |  | 
| 22 | 
|   | Species 
ludoviciana
(Nutt.) Riddell common name: 
biannual lettuce
 |  |  | 
| 23 | 
|   | Species 
muralis
(L.) Fresen. syn. Mycelis muralis
 |  |  | 
| 24 | 
|   | Species 
oblongifolia
Nutt. syn. Lactuca tatarica var. pulchella
 |  |  | 
| 25 | 
|   | Species 
pulchella
(Pursh) DC. syn. Lactuca tatarica var. pulchella
 |  |  | 
| 26 | 
|   | Species 
sagittifolia
Ell. syn. Lactuca canadensis
 |  |  | 
| 27 | 
|   | Species 
saligna
L. |  |  | 
|  | 
| 28 | 
|   | Varietas 
runcinata
Gren. & Godr. syn. Lactuca saligna
 |  |  |  | 
| 29 | 
|   | Species 
sativa
L. common name: 
garden lettuce
 |   |  | 
| 30 | 
|   | Species 
scariola
L. |  |  | 
|  | 
| 31 | 
|   | Varietas 
integrata
Gren. & Godr. syn. Lactuca sativa
 |  |  |  
| 32 | 
|   | Varietas 
integrifolia
(Bogenh.) G. Beck syn. Lactuca sativa
 |  |  |  | 
| 33 | 
|   | Species 
serriola
L. common name: 
prickly lettuce
 |  |  | 
| 34 | 
|   | Species 
spicata
(Lam.) A.S. Hitchc. |  |  | 
|  | 
| 35 | 
|   | Varietas 
integrifolia
(Torr. & Gray) Britt. syn. Lactuca biennis
 |  |  |  | 
| 36 | 
|   | Species 
steelei
Britt. syn. Lactuca canadensis
 |  |  | 
| 37 | 
|   | Species 
stolonifera
(Gray) Maxim. syn. Ixeris stolonifera
 |  |  | 
| 38 | 
|   | Species 
tatarica
(L.) C.A. Mey. |  |  | 
|  | 
| 39 | 
|   | Varietas 
heterophylla
(Nutt.) Boivin syn. Lactuca tatarica var. pulchella
 |  |  |  
| 40 | 
|   | Subspecies 
pulchella
(Pursh) Stebbins syn. Lactuca tatarica var. pulchella
 |  |  |  
| 41 | 
|   | Varietas 
pulchella
(Pursh) Breitung common name: 
blue lettuce
 |  |  |  | 
| 42 | 
|   | Species 
villosa
Jacq. syn. Lactuca floridana var. villosa
 |  |  | 
| 43 | 
|   | Species 
virosa
L. common name: 
bitter lettuce, wild lettuce, strong-scented lettuce
 |   |  | 
| 44 | 
|   | Species 
x morssii
B.L. Robins. (pro sp.) |  |  |