ATTACHED LEAVES,INFLORESCENCES, AND FRUITS OF FAGOPSIS,AN EXTINCT GENUS OF FAGACEOUS AFFINITY FROM THE OLIGOCENE FLORISSANT FLORA OF COLORADO,U.S.A.

Specimens showing staminate and pistillate inflorescences attached to branches bearing Fagopsis longifolia (Lesq.) Hollick foliage, from the Oligocene Florissant flora of Colorado, permit a relatively complete characterization of the extinct Fagopsis plant. The alternately arranged simple leaves have pinnate craspedodromous venation and prominent simple teeth. Staminate inflorescences are globose on a stout peduncle and contain anthers with tricolporate pollen. Pistillate inflorescences are ovoid heads with compact, helically arranged three-flower units and are interpreted to have three styles per flower. The infructescence consists of small wedge-shaped cupules, each containing three tiny fruits, and subtended by a persistent bract. The cupules unravel from the swollen peduncle at maturity and are often dispersed as strings of adhering fruit-wedges which frequently take on a regular, more or less circular appearance. Fagopsis is unlike any living genus but has characters which support a relationship to the Fagaceae. Unlike extant members of the family, which typically have fruits adapted for animal dispersal, Fagopsis is less obviously specialized and perhaps adapted for wind dispersal. The striking differences in fruiting structures between Fagopsis and extant Fagaceae parallel the differences between the extant genera Platycarya and Juglans in the Juglandaceae, and Alnus and Corylus in the Betulaceae.     

STEROLS OF CHLORELLA. I. THE NATURALLY OCCURRING STEROLS OF CHLORELLA VULGARIS, C. ELLIPSOIDEA, AND C. SACCHAROPHILA

The characteristics of the sterols naturally occurring in threespecies of Chlorella were examined. The algae were grown heterotrophicallyon glucose. Sterols were extracted and isolated from the lipidfraction and were characterized by means of chemical and physicaltests. Chlorella vulgaris contained three sterols. Only the principalone, chondrillasterol, was identified. Chondrillasterol hasbeen isolated previously from the genus Scenedesmus. Chlorella ellipsoidea and Chlorella saccharophila were foundto contain sterols with ß-oriented alkyl groups atC-24 in contrast to the -oriented groups commonly found in higherplants. Poriferasterol was identified as the principal sterolof both algae. Clionasterol and 22-dihydrobrassicasterol wereidentified as the two secondary sterols present. None of thesesterols have previously been reported to occur in plants. Theisolation of 22-dihydrobrassicasterol has not been previouslyreported from any natural source. ¹Scientific Article A1153, Contribution No. 3623 of the Universityof Maryland Agricultural Experiment Station. ²This work has been supported in part by a grant from the NationalAeronautics and Space Administration.     

FRESHWATER DINOFLAGELLATES OF BELIZE,C.A.

Freshwater dinoflagellates have not previously been reported from Belize, although there has been extensive work with marine dinoflagellates and some work with other freshwater groups. Freshwater dinoflagellates are more frequently observed in standing water and none have been observed in the several streams and rivers sampled since 1990. The goal in 1998 was to examine water samples from small ponds within hours of collection to improve the chance of observing swimming dinoflagellates. A plankton net was used and whole water samples also were collected. A small brown water pond on a peninsula and 30m from the Caribbean yielded a bloom of Thompsodinium intermedium. Dinoflagellates, including Peridinium centenniale, Katodinium sp., and Peridinium sp. in the Umbonatum Group, were observed within “Crocodile pond” and “Lily pond” on the mainland.     

VASCULARIZATION OF DEVELOPING LEAVES OF GLEDITSIA TRIACANTHOS L. I. THE NODE,RACHIS, AND RACHILLAE

Leaves of Gleditsia triacanthos L. are served by three leaf traces that subdivide in the node to produce subsidiary bundles. The subsidiary bundles differentiate basipetally in the stem and acropetally in the petiole using the original leaf trace bundles (those that developed acropetally) as templates for their development. Within the pulvinus, the acropetal bundle components merge to form the rachis vasculature consisting of a semicircular arc and a ventral chord; several small bundles diverge to form ventral ridge bundles. Mixing of bundles occurs during vascularization of the lateral rachillae axes. Each diverging rachilla axis receives bundles from the semicircular arc, the ventral chord, and a ridge bundle in a relatively reproducible and predictable pattern. During this process the main rachis vasculature is gradually depleted, but the ridge bundles are reconstituted following divergence of each rachilla pair. The distal rachilla pair is vascularized by a bilateral partitioning of the entire rachis vasculature; a remnant of the central leaf trace terminates in a subulate terminal appendage. Vascularization of the bipinnate G. triacanthos leaf is compared to that of the simple Populus deltoides leaf.     

SOME BIRDS OF CHICUMBANE,P.E.A.

Boshoff, A. F. &; Palmer, N. G. 1983. Aspects of the biology and ecology of the Osprey in the Cape Province, South Africa. Ostrich 54:189-204.

Information gathered opportunistically on the distribution, habitat, density, seasonality, timing of migration, food spectrum, feeding and hunting behaviour and periodicity, flight mode, influence of weather on hunting activity, interspecific and intraspecific interaction, general behaviour and conservation status of the Osprey Pandion haliaetus in the Cape Province, South Africa, is presented. The species is confined mainly to the coastal region and was recorded most frequently from the larger estuaries. Although it is basically a non-breeding migrant to the area, with peaks of occurrence during the austral summer, birds were recorded throughout the austral winter. A maximum density of 0,0028 Osprey/ha of surface water was determined; there is some evidence for an increase in the number of birds in the main study area from 1980 to 1982. The birds are persistent hunters and forage mainly in the littoral zone at water depths of up to 1,5 m, with a hunting activity peak at mid morning and at late afternoon. The food spectrum comprised 84–91% mullet (Mugilidae) of 20–700 g and 9–14% Mozambique Tilapia Oreochromis mossambicus. Flapping flight was preferred for hunting purposes and the implications of this are discussed. The study area is considered to provide optimal foraging conditions of windspeed and cloud cover for Ospreys. There was little aggressive interaction between Ospreys and resident Fish Eagles Haliaeetus vocifer and competition between these two species was not a major factor. Kelp Gulls Larus dominicanus harassed Ospreys with grey. The conservation status of Ospreys in the Cape Province is considered to be satisfactory at present.     

喜马拉雅东部雅鲁藏布江大峡弯河谷地区植被组成特点

论述了喜马拉雅东部雅鲁藏布江大峡弯河谷地区（即海拔６００～２５００ｍ）的植被组成特征。本地区原始植被主要有：（１）热带低山半常绿雨林,阿丁枫＋千果榄仁群落,阿丁枫＋小果紫薇群落,阿丁枫群落;（２）亚热带常绿阔叶林,刺栲＋阿丁枫群落,刺栲群落,短刺栲＋毛曼青冈＋西藏石栎群落,西藏栎＋毛曼青冈群落,通麦栎群落;（３）亚热带山地半常绿阔叶林,薄片青冈群落,俅江栎群落;（４）常绿针叶林,不丹松群落,喀西松     

THE COMPARATIVE DEMOGRAPHY OF RECIPROCALLY SOWN POPULATIONS OF PHLOX DRUMMONDII HOOK. I. SURVIVORSHIPS,FECUNDITIES, AND FINITE RATES OF INCREASE

Comparative demography of reciprocally sown populations for all stages of the life cycle of the winter annual, Phlox drummondii, was recorded for two seasons in natural sites. The sites investigated covered the natural range of the species and were separated by linear distances ranging from 10 to over 500 kilometers. Interpopulational variation was observed in all stages of the life cycle. Prereproductive survivorship ranged from 0 to 92 percent. Fecundity per plant ranged from 0 to 81 seeds. Finite rates of increase ranged from 0 to 34.1 yr^?1. The experimental populations with low values were growing in sites that received little rainfall or had experienced an insect or fungal infestation. The populations with high growth rates occurred in the northern sites which received greater rainfall. The relative fitness of individuals from the alien populations was compared to the local populations for all stages of the life cycle. The alien relative fitness for survivorship averaged 0.72. The average relative fitness of aliens for fecundity was 0.71 and that for finite rate of increase was 0.57. The life history parameters found in Phlox populations differ from one part of the range to another so that aliens have lower relative fitnesses than individuals indigenous to the site.     

STUDIES OF PALEOZOIC FERNS. THE MORPHOLOGY,ANATOMY, AND TAXONOMY OF ANKYROPTERIS GLABRA

Eggert , Donald A. (Yale U., New Haven, Conn.) Studies of Paleozoic ferns. The morphology, anatomy, and taxonomy of Ankyropteris glabra. Amer. Jour. Bot. 46(7): 510–520. Illus. 1959.—This is a morphological and taxonomic study of the American specimens of Ankyropteris, with the exception of A. hendricksi, that previous to this time have been referred to A. grayi, originally a Lower Carboniferous species from England, and to A. glabra, a Middle-Pennsylvanian form from Booneville, Indiana. The problem of the separation of these two closely allied species is discussed, and the original criteria for separation are questioned, on the basis of four specimens described in the present paper. The specimens are from West Mineral, Kans. and Shuler Mine in Iowa. They all have been referred to A. glabra and show extreme plasticity of several features of the plant that is correlated with the size of the stem. The major points of difference between A. glabra and A. grayi are now thought to be the presence of distantly spaced nodes in A. glabra, in contrast to closely spaced ones in A. grayi, and the presence of a small amount of mixed tissue in the stele of A. glabra, compared to a large amount in A. grayi. Well preserved axillary branches were found, whose morphology is typically that of the parent stem. It is suggested that the axillary branches were well developed in the species, and that, therefore, several orders of branching may be present in the American material. Successive orders of branching show diminution and simplification which is interpreted as an expression of the presence of determinate growth in the cauline systems of the plant, an ontogenetic pattern that is not commonly found in living forms.