Different Forms of Flowers on Plants of the Same Species

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312 CLEISTOGAJ.\'IIC FLOWERS. CHAP. VIII. They behave in this manner, apparently as a protec­tion to their pollen, and produce open flowers when exposed to the air; so that these cases seem rather different fro1n those of true cleistoga1nic flowers, and have not been included in the list. Again, the flowers of some plants which are produced very early or very late in the season do not properly expand; and these 1night perhaps be considered as incipiently cleisto­gainic; but as they do not present any of the remark­able peculiarities proper to the class, and as I have not found any full record of such cases, they are not entered in the list. When, however, it is believed on fairly good evidence that the flowers on a plant in its native country do not open at any hour of the day or night, and yet set seeds capable of gennination, these 1nay fairly be considered as cleistogamic, notwith­standing that they present no peculiarities of struc­ture. I will now give as complete a list of the genera containing cleistogamic species as I have been able to collect. TABLE 38. List of Genera including Oleistogarnic Species (chiefly after .Kuhn).* DICOTYLEDONS. Eritrichium (Boraginere). Cuscuta (Couvolvulacere). Scroph ularia (Scrophularinere ). Linaria , V andellia , Cryphiacanthus (Acanthacere). Eranthemum " * I have omitted Trifolium and Arachis from the list, because Von Mohl sayB ('Bot. Zeitung,' 1863, p. 312) that the flower-stems merely draw tbe flowers beneath the ground, and that these do not appear to be properly cleistogamic. Uorrea de Mello ('Journal Linn. Soc. Bot.' vol. xi. 1870, p. 254) observed plants of Arachis in DICOTYLEDONS. Dc:cdalacan thus (A can thacere ). Dipteracanthus , JEchmanthera , Ruellia , Lamium (Labiatre). Salvia , Oxybaphus (Nyctaginere). Brazil and could never find such flower~. Plantago has bcenomitte.d because as far as I can discover It produces hermaphrodite and ~e­male flower-heads, but not clei~­togamic tlowers. lirascheuinik.owm (vel Stellaria) has been onutted because it seems very do:lbt.ful from Maximowicz' descnpt~on whether the lower flowers wh1<:h CHAP. VIII. CLEISTOGAMIC FLOWERS. 313 TABLE 38-continued. DICOTYLEDONS. N yctaginia (N yctaginere ). Stapelia (Asclepiadre). Specularia (Campanulacere). Carnpauula , Hottonia (Primulacere). Anandria (Com posi tre ). Heterocarprea (Cruciferre ). Viola (Violacere ). Helianthemum (Cistinere). Lechea , Pa vonia (Mal vacere ). Gaudichaudia (Malpighiacere). Aspicarpa , Camarea , Janusia , Polygala (Polygalere). Impatiens (Balsaminere). Oxalis (Geraniacere). Ononis (Leguminosre ). Parochretus , Chapmannia , Stylosanthus. , have no petals or very small ones, and barren stamens or none, are cleistogamic; the upper herma­phrodite flowers are said never to produce fruit, and therefore pro­bably act as males. Moreover in Stellaria graminea, as Babington remarks(' British Botany,' 1851, p. 51) ''shorter and longer petals accompany an imperfection of the stamens Ol' germen." I have added to the list the fol­lowingcases: SeveralAcanthacere for which see J. Scott in' Journai ?f Bot.' (London), new series, vol. 1. 18?2, p. 161. vVith respect to Salv1a see Dr. Ascherson in 'Bot. Zeitung,' 1871, p. 555. For Oxy­baphu~ and Nyctaginia see Asa Gray m 'American Naturalist' Nov. ~1-)73, p. 692. From D;. 'Forrey s account of Hottonia tnjlata (' Bull. of Torrey Botan, Clu~,· vol. ii. June 1871) it is mamfest that this plant producel:i true cleistogamic flowers. For DICOTYLEDONS. Lespedeza (Leguminosre ). Vicia , Lathyrus , Martinsia vel } N eurocarpum " Amphicarprea , Glycine , Galactia , V oandzeia , , Drosera (Droseracere ). MONOCOTYLEDONS. J uncus ( J uncere ). Leersia ( Graminere ). Hordeum , Cryptost achys , Commelina (Commelinere ). Monochoria (Pontederacere). Schomburgkia (Orchidere ). Cattleya , Epidendron , The I ymi tra , Pavonia see Bouche in' Sitzungs­berichte d. Gesellsch. N atur. Freunde,' Oct. 20, 1874, p. 90. I have added Thelymitra,as from the account given by Mr. Fitzgerald in his magnificent work on' Austra­lian Orchids ' it appears that the flowers of this plant in its native home never open, but they do not appear to be reduced in size. Nor is this the case with the flowers of certain species of Epidendron, Cattleya, &c. (see second edition of my ~ Fertilisation of Orchids,' p. 147), which without expanding produce capsules. It is therefore doubtful whether these Orchid em ought to have been inclpded in the list. From what Duval-Jouve says about Cryptostachys in ' Bull. Soc. Bot. de France,' tom. x. 1863, p. 195, this plaut appears to pro­duce cleistogamic flowers. The other additions to the list are noticed in my text.