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Concentrations of airborne spores of fungi and actinomycetes were investigated from 20 samples collected during the handling of wood chips by using a six-stage fractionating impactor (Andersen sampler). Ten samples were taken on wood chip piles or beside the chip conveyor belts of cellulose factories, and ten samples were taken beside chip conveyor belts in central heating plants of saw mills. The spore exposure level varied from 103 to 106 cfu/m3 air. Wood chips used for cellulose production released large numbers of mesophilic and thermotolerant fungi, especially Aspergillus fumigatus, indicating that spontaneous heating had occurred during the storage. By contrast, heavy exposure to Penicillium species and other mesophilic fungi was characteristic of the handling of fuel chips, which are usually only stored for short periods in saw mills. The greatest spore concentration, 3×106 cfu/m3 air (mainly Penicillium), was measured during the handling of fuel chips stored for four months. Heavy exposur...

The aim of the present paper is to study the influence of air temperature on the start of Quercus pollination in Cordoba (Andalusia, Spain). Sixteen years of pollen counts were used. The start date of the pollen season in this period varied between 26th February and 7th April. Chilling requirements and heat accumulation were taken into account although no significant correlation between chilling hours and the start date was observed. Five different predictive methods based on heat accumulation were compared in this paper: 1) Number of days over a threshold; 2) Heat Units (accumulated daily mean temperature after deducting a base temperature); 3) Growing Degrees Days (Snyder 1988), as a measure of physiological growing time; 4) Accumulated maximum temperatures; and 5) Mean maximum temperature. Results indicated that the optimum base temperature for heat accumulation was 11 Co. This threshold was used in the first three methods mentioned above. Good statistical results were obtained with the five methods, y...

This is the second of two papers dealing with pollen morphology and evolution within the tribe Embothrieae. The present paper examines pollen of the subtribe Embothriinae, Embothrium (1 sp.), Oreocallis (6 spp.), Telopea (4 spp.)) in the light microscope and scanning and transmission electron microscopes. Pollen is large-sized, oblate to suboblate to oblate-spheroidal, foveolate to microreticulate to spinulate with a predominantly granular exine and simple aperture morphology. The Embothriinae are palynologically heterogeneous with both Oreocallis and Telopea each exhibiting two distinct pollen types. Pollen of New World Oreocallis (O. grandiflora, O. mucronala) and the Old World O. pinnata are closer to the Old World Telopea (excluding T. speciosissima) than to other Old World Oreocallis (O. sp. nov. O. brachycarpa, O. wickhamii). Within this complex, O. pinnata occupies an intermediate position between Oreocallis and Telopea. Despite the uniformly biporate condition in Embothrium, other pollen ...

This paper presents the course of the pollen season of selected allergenic taxa (Rumex spp., Plantago spp., Urtica spp. and Chenopodiaceae) in two towns with different degrees of urbanisation (urban, the city Szczecin, and rural, the village Gudowo in Western Pomerania, northwest Poland). The study was conducted in the years 2012–2014 with the volumetric method. The pollen of allergenic herbaceous plants was present in the air from early May until the end of September. From among the taxa studied, the genus Rumex is characterised by the longest pollination period, while the genus Urtica by the shortest. The highest percentage contribution of pollen grains to the total pollen count in the air reaching over 90% is from nettle. The pollen seasons determined for the majority of taxa are longer in the city, however the mean pollen grain counts in the air are higher for the rural area.

This is the first of two papers detailing pollen morphology and evolution with the tribe Embothrieae comprising eight genera and ca. 56 spp. The present paper examines pollen of subtribes Buckinghaminae (Buckinghamia; 2 spp., Opislhiolepis; 1 sp.), Stenocarpinae (Strangea; 3 spp.), Stenocarpus (ca. 27 spp.) and Lomatiinae (Lomatia; ca. 12 spp.) in the light microscope and scanning and transmission electron microscopes. Pollen is medium-sized, oblate, foveolate to microreticulate to reticulate, and predominantly columellate with a complex modified postvestibulate aperture morphology. Pollen data indicate ties between Lomatia and Stenocarpus on the one hand and Stenocarpus and Strangea on the other. Though Buckinghamia and Opislhiolepis have been placed in the same subtribe, the unique combination of pollen features in each suggests only a remote relationship to each other as well as to remaining Embothrieae. Comparisons to the remaining genera of Embothriae (Embothrium, Oreocallis, Telopea) and ov...

This paper is part of an investigation dedicated to indoor pollen from a forensic point of view. Previous studies documented the ‘natural’ pollen content of a flat and how it was ‘artificially’ altered by ornamental plants. The present study investigated if this ‘artificial pollen trace’ can be transferred to shoes. Brand new sneakers were worn in the flat and afterwards examined for pollen on their soles. The results showed that the shoes gathered pollen and that some pollen types correlated to those found in the flat. Afterwards, some of these shoes were worn while walking through the city for approximately 1.8 km. On these shoes, flat pollen was also detectable, but in low abundances. This study shows that, from a palynological point of view, shoes are worth a look at when a crime is investigated. Uncommon pollen grains on shoes can point to an indoor location with the corresponding ornamental plants.

The present paper analyses the pollen deposition pattern in a swampy area of tropical mixed deciduous forest at the Baikunthpur Forest Range in the Koriya District of Chhattisgarh, India, based on the palynological investigation of surface samples. The palynological assemblages revealed the dominance of non-arboreal pollen taxa (NAPs: herbs) over the arboreal pollen taxa (APs: trees and shrubs). Among the arboreal taxa, trees constitute on average 41.92% of the pollen in the total pollen rain, whereas the average contribution of shrubs is only 2.19%. Among the herbaceous taxa, Poaceae (grasses) has a relatively high frequency (average 38.20%). The NAPs, on the whole, constitute on average 53.51% of the pollen in the total pollen rain. Cerealia, Chenopodiaceae/Amaranthaceae, Caryophyllaceae, Brassicaceae, Artemisia and Alternanthera reflect the agrarian activities in the study area. Cyperaceae and other marshy taxa represent boggy places around the sampling site and Typha, Lemna, Potamogeton and Ny...

The Havana aeromycobiota diversity was studied from November 2010 to October 2011 using two complementary volumetric methods. A total of 35 fungal genera were characterised, 26 of them were recognised only by non-viable methods, six with viable methodology and the other three with both sampling methods. Furthermore, 47 species were identified by cultivation and the spores collected with the non-viable methodology. These could not be included in a specific genus, and thus, were categorised into five fungal types. In general, the main, spread worldwide, mitosporic fungi also predominated the Havana atmosphere. The predominant species were Cladosporium cladosporioides, Aspergillus flavus and Penicillium citrinum. Moreover, several Zygomycetes (Syncephalastrum racemosum, Rhizopus stolonifer and Rhizopus oryzae), Ascomycetes (Chaetomium globosum) and Basidiomycetes such as Coprinus or Ganoderma were isolated. In the present paper, the review of the airborne fungi conducted in previous studies in Cuba w...

In this paper, we present advances in studies of Compositae pollen morphology made over the past two years, focusing on the presentation of novel pollen morphological data, the potential systematic implications for presently unplaced taxa, and a bibliography of the literature. The pollen of Allittia, Castroviejoa, Lorandersonia, Pembertonia and Rhetinocarpha was found to be typical of their taxonomic placements in Astereae and Gnaphalieae, showing a helianthoid pollen type. That of Berylsimpsonia is also congruent with its current taxonomic position in Mutisieae, corresponding to an anthemoid type with an infratectum comprising two layers of robust columellae, separated by a spongy internal tectum. The pollen of Cavea, at present incertae sedis, was found to be highly distinctive with prominent, peg-like spines. The palynological data suggest affinity to Mutisieae or Vernonieae, and indicate that palynology continues to play a useful role in the systematic study of unplaced taxa. The bibliography...

Leptosphaeria maculans and L. biglobosa are fungal pathogens able to cause allergic reactions in humans and infect plants of Brassica species. The rate of their development and subsequent spore release depend on weather conditions. The aim of this paper was to pinpoint the exact meteorological conditions triggering the release of L. maculans and L. biglobosa ascospores in central and eastern Poland. Multiple regressions indicated that the frequency and amount of rainfall over short periods were important in mediating spore release. The first ascospore event depended mainly on the number of rainy days during the first 10 days of July and the cumulative precipitation during July and September. The most important variables for maximum spore release were cumulative rainfall in the beginning of July and the end of September, as well as the number of days with precipitation events in the first 10 days of August. The results highlighted for the first time the importance of the days preceding the collect...

The paper deals with the impact of meteorological conditions on in vitro pollen germination and pollen tube growth during the initial phases of male flowers development of pedunculate oak. Phenological observations of male flowers and pollen sampling were performed on the field trial established with grafted pedunculate oak clones. During the investigation, weather conditions (absolute minimum and maximum daily air temperature, minimum absolute relative humidity of air and amount of precipitation) were recorded by an automatic meteorological station installed at the field trial. Influence of meteorological conditions on pollen germination and pollen tube growth was studied in the following stages of male flower: (i) during the last ten days of flower buds dormancy, (ii) during their swelling, (iii) during the bud burst and beginning of male catkins elongation, (iv) during the final stage of male catkins elongation. Pollen germination after incubation times of 2, 4, 6 and 24 hours ranged from 0, 0 to 8, 9 % ; from 0, 0 to 55, 6 % ; from 0, 0 to 59, 3 % and from 5, 9 to 90, 7 %, respectively. Pollen tube lengths after the same incubation times ranged from 15, 3 to 45, 0 μm, from 17, 0 to 88, 3 μm, from 20, 9 to 101, 9 μm and from 39, 9 to 241, 1 μm, respectively. High temperatures and low relative air humidity during the bud burst and beginning of male catkins elongation reduced pollen germination and pollen tube growth. Weather conditions did not significantly affected pollen germination and pollen tube growth during the swelling of flower buds, as well as in the final stage of male catkins elongation.

This paper reports the pollen sources selected by Apis mellifera in the area northwest of Santa Cruz (Argentina). It evaluates the relative biomass contribution and the protein content of the collected taxa. During the apicultural period (September 2008–March 2009) pollen loads from three colonies were collected every fortnight using pollen traps. Forty-two pollen types were found in the samples, from which 15 taxa had a biomass contribution over 1% of the total pollen crop. The main pollen sources were Brassicaceae, Taraxacum officinale, Convolvulus arvensis, Rosaceae, Salix spp. and Schinus marchandii (Anacardiaceae). Of the total pollen sources identified, 15 are new records for the bee pollen flora of Argentina and 13 are native plants of South America. The contribution of native flora occurred mainly in spring. Schinus marchandii, Mulguraea-Junellia type (Verbenaceae), Adesmia spp. (Fabaceae), Sysirinchium spp. (Iridaceae), Acaena spp. (Rosaceae), Astereae and Senecio spp. (Asteraceae) were ...

The extensive pollen morphological diversity of the Cichorieae has been widely demonstrated, and previous studies have shown that in some cases pollen characters can contribute to our understanding of inter-generic relationships. This paper extends the range of genera for which pollen morphological information is available in two predominantly Old World sub-tribes, Crepidinae and Lactucinae. All the genera discussed were found to produce pollen belonging to previously described types. However, the inclusion of certain, previously under studied Asian genera and species, especially those from China, provides useful new information about the extent of pollen morphological diversity within and between genera in these subtribes, and may contribute to a better understanding of the systematics of these groups.

Pollen morphology is widely used in taxonomic treatments of tribe Vernonieae, and differences in exine structure and aperture form have been described for many species within the genera comprising the tribe. However, in recent years a number of new species have been described and, in the present paper, we describe in detail the pollen of 24 species of the tribe which are either endemic or uncommon to certain regions of Argentina or of Paraguay. The pollen of these species are radially symmetrical and more or less spheroidal, 3-colporate or, in one species, 3-porate; the exine may be tectate or semitectate and microperforate, with echinate lophae or, in the 3-porate example, psilate lophae. Using a range of characteristics related to size, shape, wall thickness, apertures and tectum surface morphology, five of the six pollen types previously described for tribe Vernonieae, and a subtype, are recognized. Our results support the usefulness of pollen morphology in helping to determine the taxonomic position of species within tribe Vernonieae. Fil: Dematteis, Massimiliano. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentina Fil: Pire, Stella Maris. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; Argentina

The Burseraceae are a medium‐sized family in which 18 genera are currently recognised. They are the subject of a long‐term project to describe the pollen morphology from light, scanning electron and transmission electron microscopy. The pollen morphology of tribe Protieae has been published, as well as an account of the pollen of the African taxa in the family. Pollen data for the other two tribes, Bursereae and Canarieae, are more or less complete. The pollen of all the genera have been examined, with the exception of the recently described Pseudodacryodes Pierlot for which, currently, there is no pollen material available. This paper summarises the results. There is considerable variation in exine and aperture features between, and occasionally within, the genera and 14 major pollen types are defined, including two previously undescribed types: ‘Canarium oleiferum’ and ‘Canarium gracile’. The distribution of pollen characteristics throughout the family is compared with previously published tribal and su...

Qinghai‐Tibetan Plateau is one of the most sensitive areas to climate change of the earth, owing to its unique topographic features and ecosystem. Soil pollen analysis is an important component of palaeo‐ecological research, while pollen preservation and the relationship between pollen and vegetation can influence the correct interpretation of fossil pollen spectra. In this paper, 36 pollen samples, which come from four meadows and two forest soil pollen profiles, have been analyzed to determine relationships between pollen and vegetation and pollen preservation on the northeastern Qinghai‐Tibetan Plateau. The relationship between pollen and vegetation shows that the surface pollen assemblages can represent regional vegetation characteristics moderately, while Betula and Populus pollen is absent in the soil surface for Betula and Populus mixed forest. Artemisia, Chenopodiaceae, Ephedra, Pinus, Hippophae etc. are over‐represented pollen taxa, Leguminosae, Ranunculaceae, Rosaceae, Gramineae etc. are under‐r...

Pollen is significant from a human health perspective because it has been known to trigger allergic respiratory disease such as asthma and hay fever. The presence of pollen in the atmosphere has been related to meteorological parameters in past studies, but this has not been done previously in Sydney, Australia. This paper reports the results of a study on Poaceae, Plantaginaceae, Casuarinaceae, and total pollen in Sydney. Pollen concentration data for the period 19 August 1992 to 31 December 1995 was examined with meteorological data for the same period. The daily pollen concentration was compared to the meteorological data for the same day and for up to three days previously. The analysis methods were Spearman's rank correlation and multiple regression. Poaceae, Plantaginaceae, and total pollen appear to be positively correlated with temperature, dew point temperature, and wind speed, and negatively correlated with air pressure. Casuarinaceae pollen is also related to these meteorological parameters, bu...

Angiosperm pollen grains can absorb or release water quickly. The respective degree of hydration has great influence upon the actual pollen grain shape and is, to a certain extent, reversible (harmomegathic effect). In the hydrated condition the majority of pollen grains are usually spherical, but in the dry condition they are infolded in a highly variable manner. This paper demonstrates many kinds of infolding within dicotyledonous tricolp(or)ate pollen from several angiosperm families. In most cases the foldings are directionally oriented, but it is only possible to predict the final form in dry condition to a limited degree.

This paper presents data of airborne pollen concentration of Pinus , Platanus , Quercus , Betula , Poaceae and Castanea , the most abundant pollen types, during the last eight years, in Santiago de Compostela (NW Iberian Peninsula). We determined their respective principal pollen release periods and analysed statistically the influence of the main meteorological parameters on their pollen concentration, obtaining a negative correlation with precipitation and a positive correlation with temperature, in the majority of the cases, during these years. A detailed study of accumulated pollen values, in relation to accumulated average temperatures and the precipitation distribution, enabled us to establish a relationship between these parameters and the principal pollination period of each of these taxa.

The Podostemaceae, or river-weeds, comprise 46 genera and 270 species of dicots and are the largest family of strictly aquatic angiosperms. Despite the large size, specialized habitats, and enigmatic morphology of the family, relatively little is known about the palynology of Podostemaceae. In the current paper, pollen morphology and ultrastructure of Marathrum schiedeanum are described. Pollen grains are relatively small, spheroidal, and tricolpate to spiraperturate. The exine has a microechinate ornament, a tectate-granular sexine and a relatively thick nexine in non-apertural regions, and a semitectate sexine and thinner nexine in apertural regions. Although aperture variation occurs in the family, this is the first report of the spiral aperture type in Podostemaceae. The spiraperturate condition appears to be derived in river-weeds, as does the granular pollen wall, which represents a reduction of the typical columellae found in eudicots.

This paper intends to elucidate the anther wall development, pollen wall development and exine substructure of Uraria crinita (L.) Desv. ex DC. (Fabaceae). The undifferentiated anther is ovoid-shaped and tetrasporangiated. The anther wall development is basic type, which is comprised of an epidermis, an endothecium layer, two middle layers and a tapetum. Anther-tapetum is glandular type and the cells are uniseriate and uninucleate. Pollen grains are tricolporate and 2-celled at the time of shedding. Before protectum development begins, a glycocalyx layer is inserted against the callose, and the plasma membrane is invaginated, exclusive of the future apertures. Subsequently, the probacula are elongate under the protectum and arise basally from the plasma membrane. The foot layer and endexine formation are concomitant with the callosic wall dissolution. The foot layer is thin and interrupted, but the endexine is thick and continuous. The intine is initially in the vacuoled stage. The substructure in the tec...

Optimal conditions for in vitro germination and tube growth of Limonium perezii (Plumbaginaceae) pollen were established. Boric acid, calcium nitrate, casein hydrolysate and sucrose were all important medium components. A dialysis tubing & filter paper support combined with using polyethylene glycol as an osmoticum in the medium provided appropriate physical conditions for L. perezii pollen germination. An in vitro pollen germination rate of about 40% was achieved. The longest pollen tube observed was four times the pollen grain diameter. While prehydration did not improve L. perezii pollen germination percentage nor the final pollen tube length, temperature influenced both of these factors. The optimum temperature range for germination was between 15°C and 35°C but the optimum temperature for pollen tube length was in the range 20°C‐25°C.

It is difficult to reliably distinguish Betula species solely on pollen morphological criteria. Size differences between the pollen of different Betula species have proved to provide a basis for their separation. Pollen grain size is affected by both sedimentary environment and laboratory treatment. Only grains from similar sediment lithologies that have had identical laboratory treatment can be considered comparable in size with each other. A simple size comparison between modern and fossil pollen is not advisable. In this paper previous methods for the separation of birch pollen types are reviewed and some new measurements of the Finnish birch species are presented and discussed.

There are at present 25 species and 26 infraspecific taxa recognized in the resurrected genus Baccharoides. Of these, 17 species and 16 infraspecific taxa are new combinations made in this paper. Full descriptions of the pollen characters of the genus as well as the floral microcharacters, synonymy and distribution are provided. Remarks on diagnostic features are also given for most taxa in a taxonomic note.

This paper aims to assess to what degree and in what way the brood chamber affects the pollen content of the honey. Twenty-nine pieces of comb containing only honey were cut from different frames of hives. The percentage of cells in each frame occupied by the brood chamber and the distance between these cells and the cut piece were recorded. A honey sample was extracted from each comb piece, avoiding any contamination with pollen, its sediment examined under the microscope and its botanical constituents identified and counted. The results show that the pollen content of honey was higher in samples from frames containing brood or pollen cells; in these samples the pollen content was positively correlated with the amount of these cells in the frame and the proximity of the honey to them. The proportion of pollen grains from principally nectariferous plants was lower in honeys with a high pollen content.

This paper reports on pollen analyses carried out in the course of a ten-year investigation, on many thousands of cytological smears coming from various organs and systems of the human body, and prepared for diagnostic purposes. The frequency and the significance of the pollen records vary according to the specific cytological field taken into account. In the urinary sediment smears, nipple secretions, and needle aspirations the polliniferous smears are very few, and the pollen number per smear is low (max 14 pollen grains, belonging always or mostly to anemophilous species). In these cases, the pollen records evidence the airborne contamination during medical procedures, the same happens with most of cervico-vaginal smears. In some cervico-vaginal smears, the high frequency of pollen grains belonging to pharmaceutical taxa suggests that lavages with vegetable components were used by the patients before undergoing the test. In nasal, bronchial and conjunctival cytology greater amounts of pollinif...

Aerobiological modelling and pollen forecasting have already been attempted with some success, notably for grasses in Europe, and ragweed in North America. But there has been no proposition for a general model of pollen curve morphology. In this paper, a methodology is suggested that allows a rationalisation of the number of aerobiological model needed to classify pollen curves and thus optimize pollen forecasting. By using descriptive parameters (of central tendency, dispersion, skewness and kurtosis) similarity coefficients were calculated for 13 taxa (chosen for their constancy, representativity and allergenicity). A cluster analysis was then undertaken that allowed the determination of inter- and intra-annual, and inter- and intra-taxonomic ratios. These ratios permit the estimation of “morphological constancy coefficients”. The most constant taxa were ragweed, mugwort, plantain and Chenopodiaceae-Amaranthaceae. The similarity of pollen curves allows the clustering of all pollen curves in thr...

In Japan, the problems of Sugi (Cryptomeria japonica)-pollinosis have been much discussed in recent papers and journals. The author made an investigation on the airborne pollen grains from a scientific standpoint in connection with the incidence of pollinosis. By using the Cascade Impactor the author collected 600 liters of air sample a day, at the roof of the Pharmaceutical Science Building, Toho University, Funabashi, Chiba, Japan. Each air sampling for 2 hrs was repeated three times a week since 1969. The airborne pollen grains in each sample were counted under the microscope to identify the pollen types. The pollen grains were classified into six types according to the classification of pollen grains in Japan established by lkuse. The accumulated number of pollen of each species was analysed statistically by circular plot, Weibull plot, Edwards plot and semi-logarithmic plot. In this report mainly 3B type of pollen grains (Cryptomeria, Chamaecyparis), collected in the last three years are des...

This paper begins a systematic SEM and LM study of the pollen grains of the Rosaceae in Western Canada with genera Agrimonia, Alchemilla, Amelanchier, Aruncus, Chamaerhodos, and Crataegus. The above genera have tricolporate-tectate pollen grains in monads. Agrimonia gryposepala and A. striata have distinct striate sculpturing perpendicular to the colpus. Alchemilla occidentalis pollen is psilate except in the colpus area which is microechinate. The exine is thickened in the intercolpium. Aruncus Sylvester pollen is very small and exhibits a coarsely striate sculpture. Chamaerhodos erecta pollen has a characteristic protruding pore area with a fusiform operculum over the aperture. The sculpturing consists of patches of short ridges. Crataegus and Amelanchier pollen have pores with a characteristic equatorial bridge or flaps when open. Dimensions of the grains vary with degree of distension. Amelanchier alnifolia pollen exhibits geographic variability. Native North American Crataegus species: C. do...

A new method has been experimented in order to identify more easily allergenic spores and pollen grains from Northern Europe described in the Atlas of Nilsson et al. (1977). It is a knowledge base system named XPER. This system based upon an automatic elaboration of a data matrix, includes for this contribution, 74 individuals (or taxa, objects) 40 variables (or characters, features) and 199 modalities (or character states). It is an on-line program type of identification (monothetic and multi-access key) working on several types of microcomputers. Four main subunits are available in this program (1) an editor to create, consult and modify the data arrangement of either taxa or characters or states; (2) a determiner to identify an unknown taxon by a step-by-step identification with possible return and several options; (3) a reorganizer to modify drastically the data and to connect several bases and (4) a printer to give as options, either only on the video display unit or simultaneously on paper ...

The paper reviews some widely used pollen morphological concepts which are slightly vague and ambiguous. To meet the needs of palynological descriptions, the terminology has to be precise and, as far as possible, numerically defined. The terms oncus, verruca, annulus, prolate and oblate are discussed and redefined. The words sculpture and structure are discusssed, delimited and defined, and it is proposed that they be accepted as terms. A new term, pseudo-annulus has been proposed.

The taxonomic basis of a paper by K. Mitra, M. Mondal & S. Saha on “The pollen morphology of Burseraceae” (Grana 16: 75–79, 1977) is criticized. Apparently, there has been no cooperation with a specialized taxonomist, no use has been made of the many recent revisions, especially of SE. Asian Burseraceae, and the voucher specimens have been cited in such a way that checking with these revisions is impossible. Among the specific names mentioned many are incorrect, and some are completely unknown in taxonomy. It is to be regretted that this in itself careful and detailed work has lost much of its value by having been done on such a shaky taxonomic basis.