Floral structure and ontogeny in Globba (Zingiberaceae)

We present new comparative morphological and ontogenetic data on flowers and bulbils of Globba (Zingiberaceae) to clarify their homologies. Globba flowers are characteristically Zingiberaceous, possessing a single stamen and epigynous (``supragynopleural') nectaries, but are unusual as the anther bears triangular lateral outgrowths and the style is held tightly in position across the curvature of the filament like a bowstring. Floral ontogeny in Globba is similar to other Zingiberaceae. Characteristic features, such as anther wings, occur late in development, shortly before anthesis. Unusually Globba has zygomorphic style anatomy with only two abaxial vascular bundles, in contrast to most other Zingiberaceae, which possess three stylar traces. The ovary is unilocular and lacks septa. Bulbils have enclosing bracts and replace flowers in the lower part of the inflorescence; they consist of a shoot with an enlarged corky storage root forming the bulk of the propagule.     

Floral anatomy of Bromeliaceae, with particular reference to the evolution of epigyny and septal nectaries in commelinid monocots

Floral anatomy is described in ten genera of Bromeliaceae, including three members of subfamily Bromelioideae, three Tillandsioideae, and four genera of the polyphyletic subfamily Pitcairnioideae (including Brocchinia, the putatively basal genus of Bromeliaceae). Bromeliaceae are probably unique in the order Poales in possessing septal nectaries and epigynous or semi-epigynous flowers. Evidence presented here from floral ontogeny, vasculature, and the relative positions of nectary and ovules indicates that there could have been one or more reversals to apparent hypogyny in Bromeliaceae, although this hypothesis requires a better-resolved phylogeny. Such evolutionary reversals probably evolved in response to specialist pollinators, and in conjunction with other aspects of floral morphology of Bromeliaceae, such as the petal appendages of some species. The ovary is initiated in an inferior position even in semi-epigynous or hypogynous species. The ovary of all so-called hypogynous Bromeliaceae is actually semi-inferior, because the septal nectary is infralocular; in these species the nectaries have a labyrinthine surface and many vascular bundles. Brocchinia differs from most other fully epigynous species in that each carpel is secretory at the apex and reproductive, rather than secretory, at the base.     

Hironoia fusiformis gen. et sp. nov.; a cornalean fruit from the Kamikitaba locality (Upper Cretaceous,Lower Coniacian) in northeastern Japan

The application of sieving techniques to bulk samples from the Ashizawa Formation, Futaba Group (Lower Coniacian) of northeastern Honshu, Japan, has yielded well-preserved mesofossil assemblages comparable with those recently described from eastern North America, Europe, and central Asia. Among the most abundant and distinctive components of these assemblages are fusiform fruits that are assigned here to a new genus and species, Hironoia fusiformis gen. et sp. nov. The fruits developed from an epigynous ovary with three to four locules. Each locule bears one seed and has a distinctive dorsal germination valve. These features of the fruit, along with the adnate calyx, indicate an affinity to extant Cornales and specifically the Cornaceae sensu lato. The recognition of an unequivocal cornalean fruit in the Early Coniacian–Early Santonian of Japan provides the earliest record of this group in the fossil record. It also establishes a minimum age for the early divergence of the asterid clade, a major group of living angiosperms comprising more than a third of all species of extant flowering plants. Electronic Publication     

INFLORESCENCE AND FLORAL DEVELOPMENT IN HOUTTUYNIA CORDATA (SAURURACEAE)

The inflorescence of Houttuynia cordata produces 45–70 sessile bracteate flowers in acropetal succession. The inflorescence apical meristem has a mantle-core configuration and produces “common” or uncommitted primordia, each of which bifurcates to form a floral apex above, a bract primordium below. This pattern of organogenesis is similar to that in another saururaceous plant, Saururus cernuus. Exceptions to this unusual development, however, occur in H. cordata at the beginning of inflorescence activity when four to eight petaloid bract primordia are initiated before the initiation of floral apices in their axils. “Common” primordia also are lacking toward the cessation of inflorescence apical activity in H. cordata when primordia become bracts which may precede the initiation of an axillary floral apex. Many of these last-formed bracts are sterile. The inflorescence terminates with maturation of the meristem as an apical residuum. No terminal flowers or terminal gynoecia were found, although subterminal gynoecia or flowers in subterminal position may overtop the actual apex and obscure it. Individual flowers have a tricarpellate syncarpous gynoecium and three stamens adnate to the carpels; petals and sepals are lacking. The order of succession of organs is: two lateral stamens, median stamen, two lateral carpels, median carpel. The three carpel primordia almost immediately are elevated as part of a gynoecial ring by zonal growth of the receptacle below the attachment of the carpels. The same growth elevates the stamen bases so that they appear adnate to the carpels. The trimerous condition in Houttuynia is the result of paired or solitary initiations rather than trimerous whorls. Symmetry is bilateral and zygomorphic rather than radial. No evidence of spiral arrangement in the flower was found.     

ANATOMY AND ASPECTS OF DEVELOPMENT OF THE STAMINATE INFLORESCENCES AND FLORETS OF SEVEN SPECIES OF ALLOCASUARINA (CASUARINACEAE)

The morphology, ontogeny, and vascular anatomy of the staminate inflorescences and florets of seven species of Allocasuarina are described. The generally terminal but open-ended inflorescences occur on monoecious or staminate dioecious trees and consist of whorls of bracts, each subtending a sessile axillary floret. Each floret consists of one terminal stamen with a bilobed, tetrasporangiate anther enclosed typically by cuculliform appendages, commonly considered bracteoles, an inner median pair and an outer lateral pair. The mature stamen is exerted, the anther is basifixed and is extrorsely dehiscent. In early development of a male inflorescence very little internodal elongation occurs and enclosing cataphylls appear. The inflorescence apex is a low dome with a uniseriate tunica and a small group of central corpus cells. Bract primordia are initiated by periclinal divisions of C₁ followed by further divisions of the corpus and anticlinal divisions in the tunica. The bracts are epinastic and become gamophyllous except apically by cell divisions in both sides of each primordium. Stomata are restricted to the axis furrows and the abaxial tips of the bracts. The axillary florets arise in acropetal succession initiated by periclinal divisions in C₁ accompanied by anticlinal divisions in the tunica. The lateral floral appendages are also initiated by C₁ followed by anticlinal divisions in the tunica. They become adnate basally later with the subtending bract. The median sterile appendages are initiated in a manner similar to the initiation of the outer appendages. The stamen is initiated by divisions in the outer layers of the corpus and in the tunica, and then develops first by apical growth followed by intercalary growth. The vascular system of the inflorescence is identical to that of the vegetative stem. Each floret is supplied by a single bundle that has its source in a branch from each of the two traces supplying a bract. Six bundles arise from the floral bundle; four of these terminate in the base of the stamen and two form an amphicribal bundle that supplies the anther. Pollen is binucleate, 3- to 7-porate. The exine is tegillate.     

无叶莲科,缅甸被子植物一新记录科

近期在缅甸北部进行野外植物考察中,发现了一种菌类寄生植物,疏花无叶莲（Petrosavia sakurai）,是缅甸被子植物一新记录科和新记录目——无叶莲科和无叶莲目。对其进行了详细的报导,并提供特征描述等数据。疏花无叶莲主要特征为茎上的鳞片状叶较疏离且彼此相距1~2 cm、总状花序、花苞片稍短于花梗、花被约1/3贴生于子房上。     

Centaurea zlatiborensis (Asteraceae,Cardueae−Centaureinae), a new endemic species from Zlatibor mountain range,Serbia

A new species of Centaurea sect. Acrocentron (Cass.) DC. (Asteraceae) found growing in dry, steppe‐like habitats on the Zlatibor mountain in western Serbia is described as Centaurea zlatiborensis. This novelity is compared with all other species of C. sect. Acrocentron known from Serbia and a diagnistic key to these is provided. Centaurea zlatiborensis is morphologically close to C. calocephala Willd. but the stems are simple or sparsely branched with monocephalous branches and itis generally smaller in all plant parts. The most important difference is the appendage morphology where C. zlatiborenis has triangular, dark brown appendages with short fimbriae and appendages not completely covering the bracts.     

COMPARATIVE STUDY OF THE FLORAL VASCULATURE IN SAURURACEAE

The floral vascular systems are compared among all six taxa of Saururaceae, including the two species of Gymnotheca which have not been studied previously. All are zygomorphic (dorsiventrally symmetrical), not radial as sometimes reported, in conformity with dorsiventral symmetry during organogenesis. Apocarpy in the two species of Saururus (with four carpels and six free stamens) is accompanied by a vascular system of four sympodia, each of which supplies a dorsal carpellary bundle, two ventral carpellary bundles, and one or two stamen traces. The level at which the ventral bundles diverge is the major difference in vasculature between the two species. The other four taxa are all syncarpous, and share some degree of stamen adnation and/or connation. The vascular systems also show varying degrees of fusion. The two species of Gymnotheca (with four carpels and six stamens) are very similar to each other; in both, the ventral traces of adjacent carpels fuse to form a placental bundle, which supplies the ovules and then splits into a pair of ventral strands. The flowers of Houttuynia cordata (with only three carpels and three adnate stamens) are sessile. Each flower is vascularized by three sympodia; the median adaxial sympodium is longer than the other two sympodia before it diverges to supply the adaxial organs. Three placental bundles also are formed in Houttuynia, but the three bundles differ in their origin. The median abaxial placental bundle diverges at the same level as the three sympodial bundles of the flower, while the other two lateral placental bundles diverge at a higher level from the median adaxial sympodium. Anemopsis californica, with an inferior ovary of three carpels, sunken in the inflorescence axis, and six stamens adnate to the carpels, has a vascular system very similar to that of Houttuynia cordata. The modular theory of floral evolution is criticized, on the bases of the known behavior of apical meristems and properties of vascular systems. The hypothesis is supported that saururaceous plants may represent a line of angiosperms which diverged very early.     

FLORAL DEVELOPMENT IN MYRISTICA (MYRISTICACEAE)

Myristica fragrans and M. malabarica are dioecious. Both staminate and pistillate plants produce axillary flowering structures. Each pistillate flower is solitary, borne terminally on a short, second-order shoot that bears a pair of ephemeral bracts. Each staminate inflorescence similarly produces a terminal flower and, usually, a third-order, racemose axis in the axil of each pair of bracts. Each flower on these indeterminate axes is in the axil of a bract. On the abaxial side immediately below the perianth, each flower has a bracteole, which is produced by the floral apex. Three tepal primordia are initiated on the margins of the floral apex in an acyclic pattern. Subsequent intercalary growth produces a perianth tube. Alternate with the tepals, three anther primordia arise on the margins of a broadened floral apex in an acyclic or helical pattern. Usually two more anther primordia arise adjacent to each of the first three primordia, producing a total of nine primordia. At this stage the floral apex begins to lose its meristematic appearance, but the residuum persists. Intercalary growth below the floral apex produces a columnar receptacle. The anther primordia remain adnate to the receptacle and grow longitudinally as the receptacle elongates. Each primordium develops into an anther with two pairs of septate, elongate microsporangia. In pistillate flowers, a carpel primordium encircles the floral apex eventually producing an ascidiate carpel with a cleft on the oblique apex and upper adaxial wall. The floral ontogeny supports the morphological interpretation of myristicaceous flowers as trimerous with either four-sporangiate anthers or monocarpellate pistils.     

FLORAL MORPHOLOGY,ORGANOGENESIS AND INTERPRETATION OF THE INFERIOR OVARY IN DOWNINGIA BACIGALUPII

The inflorescence of Downingia bacigalupii (Campanulaceae; Lobelioideae) is an indeterminate spike. Axillary flowers have a long, linear, inferior ovary with parietal placentation, a pentamerous synsepalous calyx, zygomorphic sympetalous corolla, syngenesious stamens, and a bicarpellate, syncarpous gynoecium. On the basis of floral vascular anatomy the inferior ovary is interpreted as appendicular, representing adnation of outer floral whorls to the gynoecium. Floral ontogeny shows that sepals are initiated in an adaxial to abaxial sequence rather than the 2/5 phyllotaxis reported for other members of Lobelioideae. Growth of the common bases of sepal lobes forms a floral cup and initiation of the following floral whorls occurs along the inner margins of the cup. Continued basal growth of the cup-shaped bud results in the formation of the elongated inferior ovary. Earlier evidence for the interpretation of a cup-shaped receptacle during development of epigynous flowers is reexamined and it is concluded that the concave floral bud of D. bacigalupii can also be interpreted as common growth of connate floral whorls, supporting interpretations based on vascular anatomy. Comparison of floral development between Downingia bacigalupii and Pereskia aculeata (Cactaceae) reveals ontogenetic differences between flowers with appendicular and receptacular cups.     

SYSTEMATIC ANATOMY OF THE FLOWER AND FRUIT OF COROKIA

Corokia, a genus of shrubs of New Zealand, eastern Australia, and certain Pacific islands, was first placed in Rhamnaceae, later in Cornaceae, and most recently next to Argophyllum, subfamily Escallonioideae, in Engler's monograph of the Saxifragaceae. Most manuals still list Corokia under Cornaceae from which it is readily excluded by several characters, including pluricellular T-shaped trichomes, ligulate petals, vascular bundles running longitudinally through the center of the inferior gynoecium, histology and germination of the woody endocarp, and a conspicuous subepidermal layer of tannin-containing cells. Corokia collenettei, endemic to the isolated island Rapa, retains the most primitive floral characters of the genus. Anatomical comparison of Corokia flowers with flowers of Argophyllum shows similarities that probably indicate affinity, but the relation of these two genera to others in Engler's subfamily Escallonioideae is unclear. Engler's inclusion of Berenice and Carpodetus with Corokia and Argophyllum in a tribe Argophylleae seems especially artificial.     

THE STRUCTURE OF THE ACERVULUS,THE FLOWER CLUSTER OF CHAMAEDOREOID PALMS

Developmental evidence shows that the acervulus, a distinctive flower cluster found only in the chamaedoreoid group of palms, is a form of cincinnus. In Hyophorbe indica Gaertner, the unit consists of a row of sessile flowers, the upper 3–4, staminate and the basal flower, pistillate. During initiation, each new flower originates from divisions in the T₂ and underlying layers of the lower right or left flank of the apex of the preceding flower. A bract subtending the first flower is evident in early stages, is displaced basipetally as the flowers are formed, but is obscured when flowers are mature. No other bracts are associated with the unit. One to two outer bundles of the vascular cylinder of the rachilla develop first to the uppermost flower. Subsequently, bundles to other flowers arise as lower branches of the first bundle and from other, often small outer bundles of the rachilla that become floral traces or produce one or more branches to a flower. Many of the bundles supplying the flowers bend sharply downward in the cortex of the rachilla, apparently reflecting the basipetal sequence of floral inception.     

FLORAL DEVELOPMENT IN GYMNOTHECA CHINENSIS (SAURURACEAE)

The development of the inflorescence and flowers are described for Gymnotheca chinensis Decaisne (Saururaceae), which is native only to southeast China. The inflorescence is a short terminal spike of about 50–70 flowers, each subtended by a small bract. There are no showy involucral bracts. The bracts are initiated before the flowers, in acropetal order. Flowers tend to be initiated in whorls of three which alternate with the previous whorl members. No perianth is present. The flower contains six stamens, and four carpels fused in an inferior ovary containing 40–60 ovules on four parietal placentae. Floral symmetry is dorsiventral from inception and throughout organ initiation. Floral organs are initiated in the following order: 1) median adaxial stamen, 2) a pair of lateral common primordia which bifurcate radially to produce two stamen primordia each, 3) median abaxial stamen, 4) a pair of lateral carpel primordia, 5) median adaxial carpel, 6) median abaxial carpel. This order of initiation differs from that of any other Saururaceae previously investigated. The inferior ovary results from intercalary growth below the level of stamen attachment; the style elongates by intercalary growth, and the four stigmas remain free. The floral structure of Gymnotheca is relatively advanced compared to Saururus, but its assemblage of specializations differs from that of either Anemopsis or Houttuynia, the other derived genera in the Saururaceae.     

Onobrychis dushanbensis sp. nov. endemic to Tajikistan

Onobrychis dushanbensis Ranjbar, Vitek & Karamian, a new Fabaceae species endemic to Tajikistan, is described and illustrated. The new species belongs to Onobrychis Miller subgen. Sisyrosema (Bunge) Grossheim sect. Hymenobrychis DC. It is closely related to O. chorassanica Bunge and O. seravschanica B. Fedtsch., but is easily distinguished by its purple flowers with darker venation (vs yellowish with purple venation), with wings 9–10 mm long (vs wings 4–5 mm long) and bracts 14–15 mm long (vs bracts 4–5 mm long). The relationships between the new and closely related species are discussed.     

Leaf anatomy of some Garrya species

The anatomy of the leaves of five species of Garrya has been investigated with a view to determining if this would be helpful in the taxonomic assignment of the genus, which has had a disputed taxonomic position.
Our observations indicate that the leaves of Garrya show several anatomical features which are unknown or rare in the Cornaceae, the family in which it has been included many times. These are: (a) two layers of lower epidermis; (b) papillae on the lower epidermis and sometimes on the upper as well; (c) beak-like extensions of epidermal cells adjacent to guard cells; (d) well-developed hypodermis below the upper epidermis; (e) more than one layer of palisade tissue and (f) three types of sclereids in the lamina–filiform, stellate-polymorphic and brachysclereids–distributed diffusely, subterminally or apparently terminally. These characters support the separation of Garrya from the Cornaceae and the retention of the family Garryaceae.     

INITIATION AND DEVELOPMENT OF INFLORESCENCE AND FLOWER IN ANEMOPSIS CALIFORNICA (SAURURACEAE)

All flowers of Anemopsis californica, the most specialized taxon of the family Saururaceae, are initiated as individual primordia subtended by previously initiated bracts, in contrast to the common-primordium initiation of all flowers of Saururus cernuus and of most flowers of Houttuynia cordata. Floral symmetry is bilateral and zygomorphic, and the sequence of initiation among floral parts is paired or whorled. In A. californica, the six stamens arise as three common primordia, each of which later bifurcates to form a pair. The three common primordia occupy sites corresponding to the positions of the three stamens in H. cordata flowers. In Anemopsis, the filaments of each pair are connate. Each stamen pair is vascularized by a single bifurcating vascular bundle. The three carpels per flower are usually initiated simultaneously although there may be some variation. Adnation between stamens and carpels results from zonal growth. Downward extension of the locule, and proliferation and expansion of receptacular tissue and inflorescence cortical tissue around the locule below the bases of the carpels produce the inferior ovary. The inflorescence terminates its activity as a flattened apical residuum, surrounded by bracts subtending reduced flowers most of which have stamens only.     

Eriogonum soliceps (Polygonaceae: Eriogonoideae), a new species from east-central Idaho and southwestern Montana

Eriogonum soliceps, a new species of subg.Eucycla sect.Capitata, is described. It may be readily distinguished from all other taxa of the subgenus by its reduced inflorescence. From its presumed nearest relative,E. mancum, this new species differs in its solitary (vs. 2–5) involucre, presence of a peduncle but no scape, lack of bracts at the base of the involucre, and distinctly pustulose midribs of the mature flowers.     

Psychotria elephantina sp. nov. (Rubiaceae) an endangered rainforest shrub from Cameroon

Psychotria elephantina Lachenaud & Cheek is described as a new species. It is placed in P. sect. Involucratae (Petit) Verdc., endemic to the South West Region of Cameroon and is assessed as ‘Endangered’ (EN) using the IUCN criteria. The species is distinctive in P. sect. Involucratae due to its long petioles (6.5–12.0 cm), involucres of two pairs of large free bracts and green corollas with included stamens in both longistylous and brevistylous flowers.     

姜花(Hedychium coronarium)花部维管束系统解剖学研究

姜花(Hedychium coronarium Koen.)花梗横切面整体轮廓呈椭圆形,可分为表皮、基本组织和维管束。维管束在基本组织中呈内、外两部分排列。内部维管束联结成网,形成明显外移的三束心皮背束和内方与心皮背束相间的三束隔膜束。至子房室区,心皮背束继续外移,其中主支进入花萼中脉;小分支内移,与内方一轮维管束联结,后来进入唇瓣中央及2枚侧生附属物。在花萼形成的同时,远轴面的两个隔膜中各形成一个上位腺体;同时两束远轴面隔膜束向外、两侧分别形成3束大分支,外方大分支继续外移成为2枚远轴面花瓣中脉,两侧大分支与原外方内移的子房壁维管束集合成一相连的环状维管束网,后进入唇瓣两侧;近轴面隔膜束形成3枚分支,外方分支成为近轴面花瓣中脉,两侧分支进入可育雄蕊。探讨了侧生附属物和唇瓣的来源,支持子房延长部形成的腺体为隔膜蜜腺的变异结构的观点。     

FLORAL ONTOGENY OF ILLICIUM FLORIDANUM,WITH EMPHASIS ON STAMEN AND CARPEL DEVELOPMENT

The ontogeny of the flower and fruit of Illicium floridanum Ellis, the Star Anise, was investigated. Each of 5 or 6 bracts in each mixed terminal bud subtends either a vegetative or floral bud. The solitary flowers occur in terminal or axillary positions. Each flower has 3–6 subtending bracteoles arranged in a clockwise helix. The flowers in our material have 24–28 tepals, 30–39 stamens, and usually 13 (rarely 19) uniovulate carpels. Tepals and stamens are initiated in a low-pitched helix; carpels later appear whorled, but arise successively at different levels on the apical flanks. The floral apex is high-convex in outline with a tunica-corpus configuration; it increases in height and width throughout initiation of the floral appendages. Tepals, stamens, and carpels are initiated by one to several periclinal divisions in the subsurface layers low on the apical flanks, augmented by cell divisions in the outer layers of the corpus. The carpel develops as a conduplicate structure with appressed, connivent margins. Procambium development of floral appendages is acropetal and continuous. Bracteoles, tepals, stamens and carpels are each supplied by 1 trace; the carpellary trace splits into a dorsal and an ascending ventral sympodium. The latter bifurcates to form 2 ventral bundles. The ovular bundle diverges from the ventral sympodium. Ovule initiation occurs in a median axillary position to the carpel, an unusual type of ovule initiation. The fruit vasculature is greatly amplified as the receptacle and follicles enlarge. After carpel initiation an apical residuum persists which is not vascularized; a plate meristem develops over its surface to produce a papillate structure.