In a box of Canadian Coccidæ lately sent to me by Mr. J. Fletcher, there are several species of Lecanuum, including one which appears to be new, and is described herewith.

Lecanuium Fletcheri, n. sp.

The syntypes of Leucopis annulipes Zetterstedt are described and their identities discussed. A lectotype is designated and the identity of the nominal species is established.

Over the past 20 years, ash trees (Oleaceae) in parts of the western United States of America and Canada have been subject to infestations with the psyllid Psyllopsis discrepans (Flor) (Hemiptera: Psyllidae). Infested trees show a series of symptoms, including pseudogalls, canopy loss, and in many cases, tree death. This is an expensive problem for urban forests, particularly in the context of emerald ash borer (Coleoptera: Buprestidae) and Dutch elm disease (Ophiostomataceae), which also impact the diversity of urban forests. This paper presents results from a study on the efficacy of two tree-injected insecticides, Orthene® (acephate) and TreeAzin® (azadirachtin). Trees were treated with these insecticides, and egg and adult psyllids were counted. In addition, canopy cover and severity of pseudogalling were visually assessed. Orthene reduced canopy loss and severity and amount of pseudogalling compared to what occurred on control trees; however, there were more eggs on Orthene-treated trees, indicating that any potential benefit was offset by higher egg counts after treatment. Due to the rapid decline of the ash trees, TreeAzin could not be successfully injected.

Nine Metarhizium anisopliae (Hypocreales: Clavicipitaceae) isolates were evaluated for efficacy against Melolontha melolontha (Coleoptera: Scarabaeidae) larvae, stability in culture, and the superior isolate used to produce an oil-in-water mycoinsecticide. The phenotypic and genotypic characters of four isolates with high virulence were evaluated for their stability after repeating 12 cycles of in vitro subculture. Repeated subculture did not affect the germination of conidia; however, the morphology of some isolates changed significantly. Three isolates lost their virulence, whereas the KTU-2 isolate remained highly pathogenic. Therefore, KTU-2 was selected as the superior isolate for mycoinsecticide production. After the conidia of KTU-2 were produced by solid-state fermentation using cracked rice as the substrate, the conidia were formulated as an oil-in-water emulsion and its efficacy was assessed. The formulation caused 80% mortality on Me. melolontha larvae even at the lowest application rate (1 × 105 conidia/mL) in pot experiments, and complete mortality was obtained with the concentration of 1 × 107 conidia/mL. Lethal concentrations that kill 50% and 95% of Me. melolontha larvae present were estimated as 9.29 × 103 and 2.1 × 106 conidia/mL, respectively. Oil-in-water mycoinsecticide could be a potential candidate for the commercial control of Me. melolontha and other white grubs.

The alfalfa weevil (Hypera postica (Gyllenhal); Coleoptera: Curculionidae), is a destructive pest of alfalfa (Medicago sativa Linnaeus; Fabaceae) worldwide. The biological control parasitoid, Microctonus aethiopoides Loan (Hymenoptera: Braconidae), was successfully introduced, and considered highly effective, in the eastern and mid-western United States of America. Redistribution efforts carried out throughout the 1980s reported initial establishment in the northern Great Plains, however follow-up studies to assess long-term persistence and efficacy are lacking. We resurveyed the counties in which M. aethiopoides had been initially recovered following redistribution in Montana (Flathead and Petroleum counties), Wyoming (Platte County), and South Dakota (Brookings County), to gauge whether this species has become permanently established and, if so, assess levels of parasitism in the field. We collected adult weevils from five fields in each county, and reared them in the laboratory to assess parasitism. Despite rearing more than 1000 weevils, no parasitoids were recovered from any of the locations sampled in our study, suggesting a widespread failure of M. aethiopoides to persist in the region. Thus, M. aethiopoides does not currently appear to be an important biological control agent of alfalfa weevil in the northern Great Plains. More intensive surveys will be required to assess the extent of the distributional limits of this species throughout the region.

On July 14, 1937, an infestation of Philadelphus (Mock Orange or Syringa) by a leaf miner was observed on the grounds of the Dominion Parasite Laboratory, Belleville, Ont.

Vein la of primaries present; median 4-branched; vein 8 of secondaries arising from the subcostal, more than half the length of cell from base; ♂ antennæ pectinated to the tip.

Gall at the base of the stem of Nabalus altissimus, usually in masses surronding stem, often extending down on main root, rarely on main fibres of root, usually about an inch under the ground, sometimes partly above the ground. Galls roughly spherical, 5 mm.—10 mm in diameter each containing 1–10 cells, usually aggregated in irregular cylindrical masses of 2–14, resembling small knobby artichokes or irregular small white potatoes.

Enhancement of virulence in entomogenous fungi has been a particularly neglected area of research (Roberts and Yendol 1971). It is generally believed that virulence increases following successive passage through a host and decreases following repeated subculturing on artificial media (see Aizawa 1971; Roberts and Yendol 1971). Using single-spore isolates (clones) of Beauveria bassiana (Bals.) Vuill., SamšiňSáková and Kálalová (1983) demonstrated spontaneous mutants with increased virulence. Enhancement of virulence using parasitic selection pressures has been accomplished by passage of fungal strains through a host (Daoust and Roberts 1982; references in Ignoffo et al. 1982). Such changes are thought to be due to gradual selection of genotypes.

During the summer of 1985, an intensive effort was made to collect the invertebrates, particularly insects and spiders, of the Wagner Natural Area. This is a 162-ha area 6 km west of the city limits of Edmonton, Alta., on the south side of Highway 16X.

An examination of the spiders collected in the pitfall pans revealed two species of pisaurids, Dolomedes striatus Giebel, 1869, and Dolomedes triton (Walckenaer, 1837). This is the first record of Dolomedes striatus for Alberta. The previous known western limit of its distribution was more or less between Lake Nipigon and Thunder Bay, Ont. (Carico 1973).

Field tests of several formulations of DDT and heptachlor as black-fly larvicides were made in 1953 and 1954 in irrigation canals in Alberta. The objectives of these tests were 1: to investigate further the relationship between larvicide effectiveness and the suspended solids content of the water, and 2: to investigate the use of formulations containing either emulsifiers or finely-divided inorganic particles which might improve larvicide effectiveness in clear-water streams.

The discovery of the European dandelion leaf-gall midge, Cystiphora taraxaci (Kieffer, 1888) (Diptera: Cecidomyiidae), in north-central Saskatchewan, Canada, on dandelion, Taraxacum officinale Weber (Asteraceae), is reported. This is the first record of this insect in North America. Cystiphora taraxaci is similar to Cystiphora canadensis Felt which produces galls on rattlesnake-root, Prenanthes spp., and is known only from females. Separation of the two species was achieved by demonstrating that C. taraxaci produced galls on dandelion but not on Prenanthes spp. The identity of C. taraxaci was confirmed by comparison of specimens collected in Saskatchewan with those in Europe. In Saskatchewan, C. taraxaci occurs over at least 12 000 km2 and is parasitized by Aprostocetus sp. near atticus Graham and Crysonotomyia spp. (Hymenoptera: Eulophidae).

In 1957, some officers of the Forest Insect Survey of Canada discovered a species of Nepticula mining the leaves of white birch (Betula papyrifera Marsh.) and yellow birch (Betula lutea Michx. f.) in Ontario. At that time the species was considered to be undescribed, but to confirm this it was necessary to study the life-history. This has been done by Mr. O. H. Lindquist, Forest Insect Laboratory, Sault Ste. Marie, Ontario, and the results of his studies are being presented in a companion paper. His investigations confirmed that the species had not been named and the following description is presented.

This paper describes four new species, Dialictus perpunctatulus, D. perspicuus, D. disabanci and D. paradmirandus together with the previously unknown female of D. basilicus (Sandhouse) and the male of D. atlanticus Mitchell. D. banksi Mitchell is sunk as a synonym of D. heterognathus Mitchell.

Relatedness within groups is influenced by the mating patterns of founders: the more parents that contribute to a group, the lower the relatedness of their offspring. Xylocopa virginica (Hymenoptera: Apidae) is a facultatively social bee in which low relatedness is influenced by sequential maternity. We investigated whether multiple paternity, which would occur if egg-laying females mate multiple times, might also contribute to low relatedness among female nestmates. We used two approaches to investigate how frequently females mate polyandrously. First, we used visual observations of mating behaviour to estimate mating frequencies and to evaluate evidence for temporal variation in female receptivity to mates. Second, we used a data set of microsatellite genotypes to evaluate evidence for multiple paternity based on inferred proportions of full and half sisters. Based on visual observations, we inferred a female mating frequency of 1.1 (harmonic mean). Females were more receptive early in their first nestmate provisioning phase and less receptive in their second brood provisioning phase. Based on microsatellite genotypes analysed with COLONY software, we inferred that 5–44% of female sibships included maternal half sisters, implying female mating frequencies between 1.13 and 1.41 (harmonic means). Thus, multiple mating contributes to the low group relatedness found in Xylocopa virginica.