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A comprehensive biovigilance programme was undertaken in 2018 to monitor potential insect vectors of viruses of grapevines (Vitis vinifera; Vitaceae) in two vineyards in Québec. Two hundred seventy-four insects were collected using yellow sticky traps and sweeping nets. Collected specimens were first classified into orders, with special attention given to the Hemiptera order, which is the main group of virus vectors. Hemipteran pests were identified to species. Among these specimens, one adult ofRossmoneura tectaMcAtee (Hemiptera: Cicadellidae) was identified, the first report of this species in Canada.Empoasca vinculaDeLong,Erythroneura acuticephalaRobinson, andErythroneura cymbiumMcAtee, three other species belonging to the same family and previously reported in other Canadian provinces, were also identified for the first time in Québec. Further investigations are being undertaken to test the ability of these species to transmit grapevine viruses.

Erythroneura sudra is a leafhopper occurring in northern China, which causes significant damage to fruit. The relationships between E. sudra and five fruit tree species (Rosaceae) were studied for 3 yr. The highest relative density of E. sudra was recorded on leaves of Amygdalus persica L. and Cerasus pseudocerasus Lindl. Likewise, it had the highest survival rate and shortest developmental time when it fed on these two plants species, indicating that they were the most preferred by E. sudra than the other plant species. The relative density and growth performance of E. sudra were negatively correlated with the levels of tannins and flavonoids in the leaves of the host species. Both plant species had relatively lower flavonoids and tannins, and this may have contributed to the enhanced survival and population growth of E. sudra. These results can guide the development of improved management strategies for this pest.

Modern agriculture is characterized by specialized production and the use of monoculturecropping practices. These agroecosystems are at once concentrating habitat for crop pests andeliminating habitat for natural enemies. Multiple studies have demonstrated that such changescan lead to a decrease or total loss of biological control of pests. At the same time, expansion ofmonoculture cropping systems across entire agricultural regions has led to the creation oflandscapes that are entirely dominated by a small number of crops and devoid of naturalhabitats. In the same way, entire regions can experience a reduction or loss of biological controlto agriculture.As such, a number of studies have compared crop fields with high and low habitat diversity andfound that diversified cropping systems tend to have enhance natural enemy populations andincreased biological control of pests. At the same time, another set of studies have demonstratedthat monoculture cropping systems can still experience high levels of biological control so longas they are situated in a landscape with high levels of habitat diversity surrounding them. Morerecently, it has been proposed that the use of on-farm habitat diversification to enhancebiological control will likely be influenced by the area and quality of natural habitat surroundingthe farm (i.e. landscape diversity).This dissertation was designed to evaluate the influence of habitat diversity at the local andlandscape scale on biological control of the Western grape leafhopper (Erythroneura elegantulaOsborn; Hemiptera: Cicadellidae) in North Coast wine grape vineyards. The key parasitoids of E.elegantula are Anagrus eryhthroneurae S. Trjapitzin & Chiappini and A. daanei Triapitsyn(Hymenoptera: Mymaridae). These Anagrus parasitoids are intimately tied to the natural habitatsthat surround vineyards due to the fact that in order for them to successfully overwinter theymust parasitize an alternate leafhopper host that overwinters in an egg stage (E. elegantulaoverwinters in the vineyard as an adult). These alternate leafhopper hosts are known to reside inthe natural and semi-natural habitats that surround North Coast vineyards. As such, it is thoughtthat biological control of E. elegantula in vineyards is particularly sensitive to changes inlandscape diversity. At the same time, the use of monoculture cropping practices results in avineyard environment that is very inhospitable to natural enemies of E. elegantula, includingAnagrus spp. Previous studies have demonstrated that without floral nectar (or an analogoussolution) the lifespan of Anagrus parasitoids can be less than two days and it may be that theintroduction of flowering cover crops into vineyards could possibly increase biological control ofE. elegantula by enhancing Anagrus longevity in the field. In this way, increased habitat diversityat both the field and landscape scale may support increased natural enemy populations whichwould lead to increased biological control of E. elegantula.For this dissertation, a series of studies were conducted in order to evaluate how changes inhabitat diversity at the field and landscape scale could affect natural enemy populations andultimately influence biological control of E. elegantula. First, overwintering habitat of Anagrusspp. was evaluated to identify the specific host plant species that contained leafhopper eggs thatthese parasitoids were attacking in natural habitats during the winter, as well as throughout therest of the year. Second, vineyards that were adjacent to riparian habitat were studied in orderto evaluate how distance away from a large natural habitat patch influenced the timing, densityand impact of natural enemies in the vineyard. Third, in order to isolate the influence oflandscape diversity, a multi-year study was conducted to monitor biological control of E.elegantula in a number of vineyard monocultures that were situated in low, intermediate andhigh diversity landscapes. Finally, over the course of several years the use of flowering summercover crops was developed in collaboration with commercial wine grape growers and vineyardtrials were subsequently conducted to evaluate the ability of these flowering cover crops toenhance biological control of E. elegantula. In order to evaluate how changes in the landscapeinfluenced the effectiveness of this on-farm habitat diversification practice, these cover cropstudies were conducted at multiple vineyards that were situated in low, intermediate and highdiversity landscapes.Results from these studies indicate that the area and composition of natural habitats surroundingvineyards can have a significant influence on biological control of E. elegantula. Reduced pestpopulations in more diverse landscapes is thought to be the result of both reduced crop vigor aswell as increased natural enemy impact during the overwintering period. Early seasonpopulations of Anagrus wasps were found in all vineyards regardless of landscape diversity,implying a strong dispersal capacity from overwintering sites. The Anagrus demonstrated astrong density dependent relationship with E. elegantula and this appeared to drive theirdensities in vineyards much more so than changes in landscape diversity.

The western grape leafhopper (Erythroneura elegantula Osborn) and the Virginia creeper leafhopper (Erythroneura ziczac Walsh) are the two leafhopper pests frequently observed in Washington State vineyards. Organic viticulturists have difficulties controlling these leafhopper pests, and outbreaks can result in economic loss. We vineyard-tested the efficacy of several candidate bioinsecticides and conventional insecticides against the western grape leafhopper and the Virginia creeper leafhopper. This study included the initial testing of several alternative candidate insecticides for leafhopper control. Controlled laboratory bioassays also were completed, and the 50% and 90% lethal concentrations were calculated for the nonsystemic insecticides tested. Of the bioinsecticides tested, pyrethrum (PyganicTM, Valent Bioscience Corporation, Libertyville, IL) was the only product that provided effective control of leafhoppers in both the vineyard and laboratory components of this study. In vineyard effic...

Genus. Ziczacella Anufriev, 1970 Ziczacella Anufriev, 1970, Bull. Acad. Pol. Sci. (Ser. Sci. Biol.) 17(11, 12): 697. Type species. Erythroneura heptapotamica Kusnezov, 1928 Type locality. Middle Asia Description. Body moderately slender, head narrower than pronotum. General coloration yellowish, often with pair of dark spots on crown, or sometimes lacking; brown pattern on pronotum and scutellum; zigzagged stripe on forewing. Crown angulate medially, moderately produced, broadly rounded apically. Head including eyes narrower than pronotum. Second sternal apodeme in male with posterior lobes generally not well developed. Male genitalia. Pygofer lobe rounded or subangularly produced, not reaching apex of subgenital plate posteriorly; dorsal processes movably articulated, rather long, well sclerotized, running along the inner side of pygofer lobe posteriorly. Subgenital plate gently curved upwards and rounded apically in lateral view, with 2��4 basal macrosetae. Style narrowed apically, with two slender apical and one short triangular subapical processes; inner apical process slender, apparently longer than outer one. Connective with stem absent or very short, depressed, without median anterior lobe; arms long. Aedeagus with shaft usually articulated with pair of robust pincer-shaped processes basally, rarely with shaft firmly fused to base with processes arising from base; shaft with or without processes distally., Published as part of Hossain, Md. Shamim, Kwon, Jin Hyung, Suh, Sang Jae & Kwon, Yong Jung, 2019, Taxonomic revision of the microleafhopper genus Ziczacella Anufriev 1970 from Korea (Hemiptera: Cicadellidae: Typhlocybinae), pp. 363-372 in Zootaxa 4571 (3) on pages 363-364, DOI: 10.11646/zootaxa.4571.3.4, http://zenodo.org/record/2612734, {"references":["Anufriev, G. A. (1970) Ziczacella, new subgenus of Erythroneura Fitch (Homoptera, Auchenorrhyncha, Cicadellidae). Bulletin de l'Academie Polonaise des Sciences, Serie des Sciences Biologiques, 1969, 17 (11 - 12), 697 - 700.","Kusnezov, V. (1928) Deux cicadellides nuisibles du genre Erythroneura Fitch (Homopteres). Defense des Plantes, 5, 315 - 317."]}

Erythroneura comes (Say, 1825) Recorded damage and economic importance in the orchards of Iran: A pest on grapevine and other fruit trees (Behdad 1991; Esmaili 1984). Recorded damage in the orchards of other parts of the world: Not recorded. Recorded distribution in Iran: South of Central Alborz Mountain (Mozaffarian & Wilson 2016). Conclusion: The species is a Nearctic species and the records may be due to a misidentification (Mozaffarian & Wilson 2016). Frutioidia (Frutioidia) bisignata (Mulstant et Rey, 1855) (Figs 43 and 59a–c) Recorded damage and economic importance in the orchards of Iran: Mild and sometimes significant damage on Poaceae. The phytoplasma responsible for Almond Witches’ broom disease could not be transmitted by this insect (Esmaili 1984; Rajabi 1991, Taghizadeh & Salehi 2002; Koliayee et al. 2012). Recorded damage in the orchards of other parts of the world: A pest on hazelnut in Europe and a potential pest in olive orchards in Turkey (Snare 2006; Bozbuga & Elekcioglu 2008). Recorded distribution in Iran: Northwest and centre (Mozaffarian & Wilson 2016). Conclusion: Modarres Awal (1994) mentioned the name: “ Erythroneura albisignata ” as a synonym with Z. bisignata which is the synonym of the present species. It has been repeated in some agricultural websites consequently as a pest on Poaceae. However, this is not a valid name. The economic injury level caused by the species is unclear., Published as part of Mozaffarian, Fariba, 2018, An Identification key to the species of Auchenorrhyncha of Iranian fauna recorded as pests in orchards and a review on the pest status of the species, pp. 475-501 in Zootaxa 4420 (4) on page 492, DOI: 10.11646/zootaxa.4420.4.2, http://zenodo.org/record/1455385, {"references":["Behdad, E. (1991) Pests of Fruit Crops in Iran. Markaz-e Nashr-e Bahman, Isfahan, 822 pp.","Esmaiili, M. (1984) Important Pests of Fruit Trees. Markaz-e Nashr-e Sepehr publication, Tehran, 584 pp. [in Persian]","Mozaffarian, F. & Wilson, M. R. (2016) A checklist of the leafhoppers of Iran (Hemiptera: Auchenorrhyncha: Cicadellidae). Zootaxa, 4062 (1), 1 - 63. https: // doi. org / 10.11646 / zootaxa. 4062.1.1","Rajabi, Gh. (1991) Insects attacking Rosaceous fruit trees in Iran. Vol. 3: Homoptera. Ministry of Agriculture, Tehran, 256 pp.","Taghizadeh, M. & Salehi, M. (2002) Leafhoppers of subfamily Typhlocybinae found on almond (Prunus anygdalus) in Fars Province. Proceedings of 15 th Iranian Plant Protection cogress, Kermanshah, Iran, 2002, 92 - 93.","Snare L. (2006) Pest and Disease Analysis in Hazelnuts. Horticultural Australia Ltd, 64 pp.","Bozbuga, R. & Elekcioglu, Z. (2008) Pests and Natural Enemies Determined in Olive Orchards in Turkey. Turk Bilimsel Derlemeler Dergisi, 1 (1), 87 - 97.","Modarres Awal, M. (1994) List of Agricultural Pests and Their Natural Enemies in Iran. Ferdowsi University of Mashhad Publication No 147. Ferdowsi University of Mashhad, Mashahd, 364 pp."]}

Erythroneura comes (Say, 1825) Erythroneura comes (Say, 1825): 343. Erythroneura comes (Say, 1825): Esmaili (1984), Behdad (1991), Modarres Awal (1994) [listsed]. Recorded distribution in Iran: South of central region of Alborz mountains. Comment: This a is Nearctic species. There are no records from the Old World. The source of the identification of this species in Iran is not clear and the above records do not appear to be based on the examination of specimens., Published as part of Mozaffarian, Fariba & Wilson, Michael R., 2016, A checklist of the leafhoppers of Iran (Hemiptera: Auchenorrhyncha: Cicadellidae), pp. 1-63 in Zootaxa 4062 (1) on page 47, DOI: 10.11646/zootaxa.4062.1.1, http://zenodo.org/record/256796, {"references":["Esmaiili, M. (1984) Important Pests of Fruit Trees. Markaz-e Nashr-e Sepehr publication, Tehran, 584 pp [In Persian].","Behdad, E. (1991) Pests of fruit crops in Iran. Markaz-e Nashr-e Bahman, Iran, 822 pp [In Persian]","Modarres Awal, M. (1994) List of Agricultural Pests and Their Natural Enemies in Iran. Ferdowsi University of Mashhad publication, No 147, Mashahd, 364 pp."]}

Species of Erythroneurini (Cicadellidae: Typhlocybinae) currently placed in the genus Zygina and found in Australia, New Zealand and some neighbouring islands are transferred to the new genus Anzygina, type species Erythroneura sidnica Kirkaldy, following comparison with the type species of the genus: Typhlocyba nivea Mulsant and Rey. New combinations are Anzygina sidnica (Kirkaldy), Anzygina honiloa (Kirkaldy), Anzygina melanogaster (Kirkaldy) and Anzygina sativae (Evans) from Australia, Anzygina toetoe (Cumber), Anzygina agni (Knight), Anzygina dumbletoni (Ghauri) and Anzygina ramsayi (Knight) from New Zealand, Anzygina zealandica (Myers) from Australia and New Zealand, Anzygina jowettae (Knight) from Norfolk Island and Anzygina medioborealis (Ghauri) from Papua New Guinea. Lectotypes are designated for Erythroneura honiloa Kirkaldy and E. sidnica Kirkaldy. Anzygina billi sp.n. is described from SE Qld, and Anzygina barrattae sp.n. is described from the South Island of New Zealand. A. agni is a new record for Australia and is presumed to be Australian in origin. A. dumbletoni has a distribution which suggests that it also is introduced to New Zealand although its origins are not known. A. ramsayi, A. barrattae and A. toetoe, all of which appear to be New Zealand endemics, show affinity with each other based on aedeagal structure. A key to these species, based on males, is provided. The lack of male syntypes for Erythroneura honiala Kirkaldy and Erythroneura lubra Kirkaldy precludes establishment of their identities relative to other species of the genus, and both names are regarded as having nomen dubium status. Australian species not transferred to Anzygina are Zygina evansi (Ross) and Zygina ipoloa (Kirkaldy), both of which belong elsewhere.

This review provides descriptions, illustrations, keys for identification, and summaries of distributions and host plants for all known species of the genera Erythroneura (54 species), Erasmoneura (12 species), Rossmoneura (3 species), and Hymetta (5 species). Erythroneura browni sp.n., E. ortha sp.n., E. carinata sp.n., E. glabra sp.n., E. bakeri sp.n., E. kerzhneri sp.n. from Central and Eastern USA, E. triapitsyni sp.n. from New Mexico, Erasmoneura margaritae sp.n. from Illinois, and E. emeljanovi sp.n. from South Carolina are described as new. The following new synonyms are recognized: Erythroneura prima Beamer equals E. maritima Hamilton syn. n.; E. diva McAtee equals E. tricincta var. complementa McAtee syn. n.; E. octonotata Walsh equals E. comes var. compta McAtee syn. n., E. cherokee Robinson syn. n., E. compta var. rufomaculata McAtee syn. n., and E. nigroscuta Johnson syn. n.; E. cymbium McAtee equals E. tricincta var. disjuncta McAtee syn. n.; E. calycula McAtee equals E. tricincta var. erasa McAtee syn. n. and E. tricincta var. noncincta Johnson syn. n.; E. ziczac Walsh equals E. ziczac var. walshi Beamer syn. n.; E. delicata McAtee equals E. comes var. accepta McAtee syn. n., E. scripta Robinson syn. n., and E. tudella Robinson syn. n.; E. rosa Robinson equals E. repetita McAtee, syn. n.; E. kerzhneri sp.n. equals E. vaga sensu Beamer, 1938 (not Johnson, 1934); Erasmoneura vulnerata Fitch equals E. gradata Robinson syn. n.; Erasmoneura fulmina McAtee equals E. bicolorata Beamer syn. n.; Erasmoneura nigra Gillette equals E. vulnerata var. decora McAtee syn. n.; Erasmoneura nigerrima McAtee equals E. atrata Johnson syn. n.; Hymetta balteata McAtee equals H. trifasciata var. albata McAtee syn. n. and H. balteata var. mediana Fairbairn syn. n.; H. anthisma McAtee equals H. distincta Fairbairn syn. n.; Erasmoneura atra Johnson, 1935 is restored and equal to E. nigerrima sensu Beamer, 1946 (not McAtee, 1920). Neotypes are designated for Erythroneura octonotata Walsh, E. tricincta Fitch, and Hymetta trifasciata Say.

We report a two-step method to rear three leafhopper species,Erythroneura elegantulaOsborn,Erythroneura vitis(Harris), andErythroneura ziczacWalsh, for experimental purposes on grapevines. The first step involves rearing adults on grapevines for reproduction, oviposition, and egg development. The second step involves rearing nymphs on isolated leaves placed in Petri dishes lined with agar. No mortality was observed and adults emerged in about three weeks. The threeErythroneuraspecies were reared for 10 consecutive generations with minimal resources.

The 2 most important leafhopper pests of grapes in Washington are the Western grape leafhopper, Erythroneura elegantula Osborn, and Erythroneura ziczac Walsh. The influence of different constant temperatures on the egg and nymphal stages of E. ziczac and on the nymphal stage of E. elegantula was examined. Development times of E. ziczac eggs ranged from 33.1 d at 15 degrees C to 8.6 d at 32.5 degrees C. E. ziczac nymphal development ranged from 40.2 d at 16 degrees C to 11.1 d at 29.5 degrees C. The average number of degree-days required for development from oviposition to imaginal molt was 435.4. This was slightly higher than the previously published value of 390.5 DD for field reared E. ziczac. E. elegantula nymphal development ranged from 38.0 d at 16.0 degrees C to 11.8 d at 32.5 degrees C. The average number of degree-days required for E. elegantula development from eclosion to imaginal molt was 246.3. Constant temperature data for the egg and nymphal stages of E. ziczac and for the nymphal stage of E. elegantula was fitted to a developmental model based on enzyme reaction kinetics. The egg and nymphal stages of E. ziczac fitted the model with r2 values of 0.9992 and 0.9990, respectively. The E. elegantula nymphal stage fitted the model with an r2 value of 0.9996. Lethal freezing temperatures for E. ziczac adults collected on 28 January, 4 February, and 14 November, 1994 were -27.1, -26.3, and -27.2 degrees C, respectively. Freezing temperatures for E. elegantula on the same dates were -24.6, -24.1, and -25.3 degrees C, respectively.

Species composition of Erythroneura leafhoppers infesting the 3 major classes of grapes grown in New York was investigated. Eastern grape leafhopper, E. comes (Say), comprised 74–100% of populations collected on the native American ( Vitis labrusca Bailey) cultivars ‘Concord’, ‘Niagara’, ‘Catawba’ and ‘Delaware’. On interspecific hybrid ( Vitis sp .) and Vitis vinifera L. cultivars, E. comes was largely absent, and 97–100% of leafhoppers collected were 2 cryptic species, E. bistrata McAtee and E. vitifex Fitch. On the native American variety ‘Elvira’, a V. labrusca X V riparia Michaux hybrid, field populations were 24% E. comes and 74% the E. bistrata/vitifex complex. E. vitis (Harris), E. tricinta Fitch, and E. vulnerata Fitch were also present in commercial grapes, but never exceeded 20% of the populations sampled. Populations on wild V. riparia adjacent to vineyards were comprised of 24% E. comes , 47% E. histrata/vitifex , 19% E. vitis , and 10% E. tricinta . Dissection revealed that proportions of E. bistrata and E. vitifex in field collections, varied from 97% E. bistrata to 61% E. vitifex . Oviposition of E. comes and E. bistrata on V. vinifera , interspecific hybrid, and native American cultivars was compared in greenhouse choice tests and field no-choice tests. In choice tests, E. comes laid more eggs on Concord and Elvira than on the interspecific hybrid ‘Seyval blanc’, or the V. vinifera cultivar ‘White Riesling’. E. bistrata did not oviposit on Concord when paired with either Elvira, Seyval blanc or White Riesling. When caged to grape leaves in no-choice tests, E. comes laid the most eggs on native American cultivars and the fewest on V. vinifera and interspecific hybrids; E. bistrata laid the most eggs on hybrid and V. vinifera cultivars, and very few eggs on three native American cultivars. These results show that E. bistrata and E. vitifex are the principal pest species on V. vinifera and many interspecific hybrid cultivars in New York, and that E. comes is the principal leafhopper pest on native American V. labrusca cultivars.

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Caged ‘Concord’ grapevines were artificially infested with “low” and “high” populations of the leafhopper, Erythroneura comes Say, between early July and late August from 1979 to 1982. Foliage injury became evident shortly after the first introductions and increased during the season. At harvest, the injury inflicted by the “high” populations in the caged vines was similar to or higher than the injury inflicted by natural populations of E. comes in commercial vineyards. The caged grapevines injured by E. comes produced fruit yields and juice quality that did not differ significantly from the noninfested caged vines. In addition, vine vigor was not reduced by the leafhopper injury. Concord vines may be able to withstand greater injury from first- and second-generation E. comes than was previously believed. Lacking in this study was foliage injury that may occur during June from overwintered leafhoppers as they first enter vineyards. This is the main period of berry and cluster primordia initiation, the major contributing factors to fruit production.

An illustrated key based on characters of the genitalia is provided for distinguishing 8 species of leafhoppers of the maculata group of the genus Erythroneura which occur sympatrically over much of the range of their specific host plant, the American sycamore, Platanus occidentalis L. These species are E. arta Beamer, E. bella McAtee, E. hymettana Knull, E. ingrata Beamer, E. lawsoni Robinson, E. morgani (DeLong), E. torella Robinson, and E. usitata Beamer. Studies of this ecologically important group of species are needed to help resolve debates on competition and coexistence of organisms. The key is provided to make these species generally available for study by field biologists.

Phenology and relative abundance of the homopteran complex, including Macropsis fumipennis (Gillete and Baker), Stragania alabamensis (Baker), Empoasca fabae (Harris), Erythroneura clavata DeLong (Cicadellidae), and Micrutalis calva (Say) (Membracidae), were monitored on ornamental honeylocust, Gleditsia triacanthos L., near Wooster, Ohio. M. fumipennis, the most abundant species, completed its life cycle by late July. S. alabamensis was present from just after budbreak until frost, with collection data suggesting it is bivoltine. E. fabae and E. clavata adults were present from mid-June to early October. M. calva nymphs emerged in the spring and adults disappeared by mid-July, returning to honeylocust in early September. A second generation may develop on alternate hosts in summer. Observed foliar injury is attributed to the sympatric honeylocust plant bug, Diaphnocoris chlorionis (Say) (Hemiptera: Miridae), and not the homopterans reported here.

The number of new records noted in the Canadian Insect Pest Survey in 1952 was somewhat larger than usual and these and others are brought totether for convenient reference in this paper. Canadian sources of information include Survey reports submitted by officers of the Entomology and Forest Biology divisions, provincial entomologists, and other co-operators; The Canadian Insect Pest Review; Annual Report of the Entomological Sociery of Ontario; The Canadian Entomologist; Annales de l'Acfas; and Proceedings of the Entomological Society of British Columbia. A reference to the collection of the leafhopper Erythroneura flammigera (Geoffr.) on cherry in British Columbia was noted in Science News Letter, a United States publication, and details of the occurrence were obtained from H. H. Ross of the Illinois Natural History Survey.

Empoasca libyca is a major pest of cotton in the northern and western blocks of the Gezira Irrigated Scheme.Distribution of the species of the genus of Empoasca and Erythroneura lubiae is given, together with their food plants in the Sudan.Damage caused by E. libyca is noted; an experiment carried out in 1935/36 showed that Jassids were able to cause such symptoms.The life-cycle shows that the egg and nymphal stages are of short duration (8 days each) and followed by a long adult life (as long as 2 months) in which the female lays her eggs over a long period.A new type of cage was used and is figured.The effect of applications of Bordeaux mixture in reducing the Jassid population and amount of scorch is given as well as physiological data relating to the influence of spraying on different parts of the Jassid-infested cotton plants. It is shown that sprayed plants produced an appreciable increase in the number of green bolls formed and an increase of 11 per cent, in the weight of seed cotton per boll harvested. It is pointed out, however, that Bordeaux mixture has several disadvantages and other more suitable insecticides are being sought.No Sakel varieties as yet have shown resistance to Jassid attack.

In New Brunswick at least nine species of Erythroneura leafhoppers feed and oviposit on birch trees. The appearance and ecological requirements of two species in the subgenus Eratoneura are described.

General ground color semihyaline to yellowish white marked with orange or red. Vertex with semblance of three white spots more or less surrounded with orange bands. Median white spot elongated. Pronotum with median Y-shaped orange mark, touching both margins, usual angular mark behind each eye. Scutellum with spot on tip, basal angles yellow. Clavi with basal anchor-shaped mark and rectangular spot before tip. Coria with angulate vitta arising on costa midway between plaque and humeral angle, reaching to claval suture. Another irregular-sided, zigzag, vitta arising at anterior end of plaque, more or less surrounding it and ending just before base of cell M4. Black spot in posterior end of plaque and base of cell M4. Tips of tegmina more or less dusky. Cross-veins red. Venter stramineous.

Tests conducted with home-made Bordeaux: Mixture, 4–4–50 formula and also with three proprietary preparations of this compound, indicate that these spray materials are toxic to the nymphs of at least one common and injurious cicadellid, namely: Empoasca mali Le B. They also are apparently toxic to the nymphs of three other species of leafhoppers, namely: Empoa rosae Linn, Erythroneura comes Say, and E. tricincta Fitch. The young nymphs are more susceptible to the action of the Bordeaux than the older ones, while the adults, although they are repelled from plants sprayed with this preparation, are not affected when forced to feed from treated leaves. Bordeaux mixture should therefore be classed as a specific insecticide for certain species of leafhoppers.

Effect of severe drouth on apple leafhoppers was observed. The three species of Erythroneura were practically absent during the early summer, but gradually increased in numbers as the season advanced. The severe drouth shortened the life of T. pomaria first brood adults in some sections and the second brood did not develop into injurious numbers.

In connection with the investigation of a possible vector of the Eckelrader virus disease of sweet cherry in the Netherlands, an examination was made of the leaf hopper fauna of cherry. Five species were found breeding regularly on this hostplant viz.Typhlocyba quercus (F.),Erythroneura alneti (Dhlb.),Erythroneura flammigera (Geoffr.),Empoasca flavescens (F.), andEupteroidea stellulata (Burm.). Some details about their biology are given. Other leafhopper species found on cherry, but which are probably only there by accident, are mentioned.

While conducting investigations on the life history and control of the grape leafhopper ( Erythroneura comes Say) in Erie County, Pennsylvania, the author had occasion to observe a series of outbreaks of this insect and to accumulate certain pertinent bits of information concerning the relation of weather factors to such outbreaks.

Many of the small leafhoppers that feed and reproduce upon the foliage of birch trees belong to the subfamily Typhlocybinae. The main species are Typhlocyba hockingensis Knull, T. pomaria McAtee, Ribautiana foliosa (Knull), Edwardsiana bergmani (Tullgren), Empoa latifasciata Christian, Dikrella cruentata (Gillette), Alebra albostriella (Fallen) and several Erythroneura species. Their ecological requirements and life histories are described. Notes on morphology and illustrations of each species except the Erythroneura are included.