The classification of the agaves is very perplexing. This is partially owing to the number of species, to the scarcity of preserved study material, and to the infrequency of flowering in many species. In fact, many species have never been known to flower. The most usable characters for classification are to be found in the leaves, of which the end-spine and marginal prickles are very characteristic, and, although such an arrangement is more or less artificial, it is the most satisfactory in naming a collection. From a botanical point of view, however, the inflorescence shows the true relationship of the species. In this way the genus is usually divided into three groups or subgenera. These are: First, Euagave, having a paniculate inflorescence, with candelabra-like branches, Second, Littaea, having a dense spike of usually paired flowers. (The section Litteae has been considered by some a good genus, but it seems to connect with the first section through certain species.) The third section, Manfreda, is very different from the above, and is now considered as a distinct generic type, and so treated here. Manfredas are all herbaceous, appearing each year from a bulbous base: the leaves are soft and weak, dying down annually, while the inflorescence is a slender open spike, with solitary flowers from the axils of bracts.
The following names occur as being in cult.: A. Bakeri, Hook, f. Resembles a gigantic eremurus in habit. Fls. with pale greenish yellow segms. Mex. (?). Gn. 61, p. 240.— A. carchariodonta. Allied to A. Ghiesbrechtii. Lvs. flatter, narrower and more spiny.— A. Langlassei, Andre. General habitas of Furcraea Bedinghausei. Infl. about 3 ft. high. Mel. R.H. 1901: 349.—A. littaeoides Allied to A. Scolymus. Stemless: lvs. strongly prickly toothed, terminated by a stout spine: fls. greenish yellow.—A. Pavoliniana. Stemless:
fls. green-yellow.—A. Watsonii. Allied to A. horrida. Distinguished by extremely narrow border of the lf. Probably Cent. Amer.— A. Weberi. Distinguished by almost complete absence of marginal teeth. Mex.—A. Wrightii. J. R. Drumm. Allied to A. geminiflora. Has been cult. under name of A. Taylori. Trunk short: margins of lvs. sharp without teeth or prickles: perianth dark green with cream-white borders. Cent. Amer. B.M. 8271.
INDEX.
abortiva, 33. Besseriana, 6. cochleata, 11.
adornata, 48. Bignetii, 48. coerulescens, 36.
albicans, 30. Bonapartea, 49. Cohniana, 54,
albida, 11. Bonnetii, 11. compacta, 11, 47.
altissima, 21. Bonnetiana, 11, 18.
compluviata, 19.
americana, 19, 21. Boscii, 49. concinna,
6.
amaena, 11. Botterii, 34. Considerantii,
44.
amurensis, 43. bracteosa, 55. Cookei, 1.
anacantha, 2. brevifolia, 47. Corderoyi, 5.
ananassoides, 8. brevis, 2. cornuta,
43.
angustifolia, 1. bulbifera, 9. Couesii,
14.
angustissima, 48. candicans, 6.
crassispina, 19.
applanata, 13, 14. candida, 6. crenata,
11.
artichaut, 40. caribaea, 32. Croucheri, 11.
atricha, 49. Celsiana, 31. ctenophora, 30.
atrovirens, 19. Celsii, 31. cucullata, 11.
attenuata, 28. chiapensis, 33, cyanea, 10.
auricantha, 11. chihuahuana, 15.
cyanophylla, 10.
Bakeri, 5. chloracantha, 32.
dasylirioides, 53.
Beaucarnei, 39. coarctata, 18. dealbata, 51, 53.
Beauleuriana, 10. coccínea, 12.
decipiens, 4.
Bessereriana, 6. cochlearis, 19. denea,
33, 47.
densiflora, 31, 33. lucida, 10. Richardeii, 51.
depauperata, 47. lurida, 1, 10. rígida, 2, 3, 7.
desertí , 25. macracantha, 6. rigidissima, 39.
DeSmettiana, 8, 42. macroacantha, 6. robusta, 47.
Diguetii, 48. macroculmis, 12. Roezlei, 50.
diplacantha, 39. macrodonta, 39. Roesliana, 40.
distans, 39. Maigretiana, 42. Rohanii. 41.
echinoides, 51. major, 6, 39, 43, 47. Romani, 35,
47.
elegans, 11. Manguai, 9. roses, 51. Ellemeetiana,
29. Mapisaga, 19. rotundifolia, 11. elliptica,
28. Marcussi, 14. rupicola, 32. elongata, 6.
marginata, 1, 19, 21. Salmdyckii, 33.
ensifera, 37. maritima, 48. Salmiana, 19.
ensiformis, 51. marmorata, 23. Sargentii, 1.
europeae, 21. massiliensis, 21,33. Saundersii,
11. falcata, 52. Maximiliana, 43. schidigera, 48.
ferox, 17. medio-picta, 3, 21,30, schiedigera,
48.
filamentoes, 47. 43. Schottii, 45. filifera, 47,
48. melliflus, 19. Scolymus, 12.
flaccida, 12. mesotillo, 36. Sebastiana, 16.
flavescens, 6. mexicana, 9, 19, 22 serrulata, 45.
fourcroydes, 3. micracantha, 30, 32, 42 Shawii,
16. fragilis, 41. silvestris, 3
Fransosinii, 20. Milleri, 21, 22. Simonii, 11.
Funkiana, 36. minima. 3. Simeii, 11
geminiflora, 49. minor, 47. sisala, 2.
Ghiesbrechtii, 41. miradorensis, 8. sisalana, 2.
Ghiesbreghtii, 41, 42. mitis, 32. spectabilis, 21
gigantea, 6. mitraeformis, 18. spicata, 54.
Gilbeyi, 40. Morganii, 42. spiralis, 4.
glauca, 6, 51. multiflora, 33. squalidens, 41.
glaucescens, 28, 32. multilineata, 36.
stenophylla, 36.
Goldmaniana, 16. nana, 6, 51. streptacantha, 11.
gracilipes, 14. neglecta, 7. striata, 21, 50, 51.
gracilispina, 19. Newberryi, 27. stricta, 51.
grandibracteata, 11. Nickelsiae, 44. subdentata,
29.
grandidens, 41. nigrescens, 36. subfalcata, 6.
grandidentata, 41. nigrispina, 6. subintegra, 39.
granulosa, 42. Nissoni, 36. subundulata 28.
Guignardii, 11, 28. Noah, 15. sudburyensis, 6.
Hanburii, 40. ' obscura, 41. superba, 1.
Havardiana, 14. orbicularis, 11. Taylori, 33, 47,
49.
Haworthiana, 10. Orcuttiana, 16. tehuacanensis.
11, 18.
heteracantha, 36, 38. Ortgiesiana, 48. tequilana,
4.
histrix, 51. Ottonis, 33. tetragona, 36.
horrida, 39, 40, 42. Ousselghemiana, 30. Todaroi,
23.
Houghii, 54. ovalifolia. 11. torta, 43.
Houlletiana or Houllettii, 2. pachyacantha, 16.
Toumeyana, 45.
huschucensis, 14. Palmeri, 24. triangularis, 39.
hybrida, 43. parrasana, 15. Troubetskoyana, 23.
hystrix, 6, 51. Parryi, 14. uncinata, 33.
inermis, 36. parviflora, 46. undulata, 23.
Inghamii, 40. Patonii, 15. univittata, 37.
integrifolia, 6. paucibracteata, 28. utahensis,
27.
intrepida, 53. paucifolia, 6, 50. Vanderdonckii,
43.
ixtli, 2, 3. Peacockii, 40. variegata, 47.
iitlioides, 1, 3. perbella, 37, 43. vera-crucis,
9. Jacquiniana, 1. perplexans, 46. vera-
crux, 9. juncea, 49. Pfersdorffii, 35, 43.
vera-crux, 9. Karwinskii 5. picta 22. verse
crucis 9. Kerchovii, 39. Pilgrimii, 42.
Verschaffeltii, 11.
Killischii, 40. polyscantha, 33. vestita, 48.
Knightiana, 48. polyphylla, 10. Victoriae
Reginae, 44.
Kochii, 43. Poselgeri, 36. Villae, 43.
laetevirens, 21. potosina, 19. Villarum, 43, 47.
laevior, 40. princeps, 48. virginia, 21.
lanceolata, 11. prolifera, 3. viridis, 6, 22.
laticincta, 41. pseudofilifera, 47. vivipara, 1,
7. latifolia, 4, 6, 28, 43. pugioniformis, 6.
Whitakeri, 19.
latissima, 19, 28. pulverulenta, 11. Wightii, 1.
laxifolia, 4. purpurea, 51. Wislizeni, 15.
Lecheguilla, 36. quadrata, 11. Wolkensteinii, 33.
Leguayana, 41. quiotifers, 19. Woodrowii, 1.
Lemairei, 39. ramosa, 21. Wrightii, 49.
Leopoldii, 11, 47, 48. recurva, 50. xalapensis,
35.
lepida, 10. reccurvata, 7. xylonacantha, 43.
linearis, 6. Regelii, 40. yuccaefolia, 54.
longifolia, 3, 6, 22, 43, 47. Regeliana, 8, 40.
Zapupe, 4. rhomboidea, 11. zonata, 19.
lopantha, 37.
A. Infl. a candelabrum-like panicle. (1-26.) Subgenus Eugave.
B. Lvs. dagger-like or sword-shaped: spine not decurrent: fls. rather large, greenish, long-lobed. ill-smelling, often followed by bulbils; seeds very large. Trunk often developed.
C. Fls. urceolately contracted in throat.
CH
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