It is well known that the accidental introduction of some plants into certain parts of the world has later led to noxious weed problems of varying degrees of acuteness. Concrol of such alien plants by cultural or chemical methods may be unsatisfactory or economically impracticable and recourse is made to biological methods in the form of insect enemies etc. It was in circumstances of this nature that the Government of Nigeria requested the C.I.B.C. to investigate the possibilities of the biological control of the weed Acanthospermum hispidum D.C. Despite the discouraging facts that the weed is an annual and related to plants of economic importance in the family Compositae, and that the entomological method is appropriately regarded as being of very restricted application in these instances, the nature of thc problem for Nigerian agriculture was such that a preliminary investigation of the status of the plant in its native South American home seemed warranted.

In 1947, while a caragana breeding improvement program was being carried out on the Forest Nursery Station, Indian Head, Saskatchewan, it was discovered that a large percentage of seed was being destroyed by an insect. This insect, the caragana seed chalcid, which interfered seriously with the plant breeding work, is apparently identical with the Russian Bruchophagus caraganae (Nik.) (Nikol'skaya, 1952).

The relative importance as pollinators of alfalfa of each of the 14 species of Megachile that occur in southern Alberta has been assessed on the basis of Alberta distribution, frequency and abundance in mixed prairie, nesting habits, pollen preferences, and flight period; two ground-nesting species of the subgenus Xanthosarus Rob., Megachile perihirta Ckll. and M. dentitarsus Slad., were judged the principal pollinators (Hobbs and Lilly, 1954).

The toxic effects of a number of orchard spray chemicals on predators and parasites were given in an earlier paper (MacPhee and Sanford, 1951), which presented results obtained before 1953 and gave a list of biotic control agents, their hosts, and periods of activity. It also gave a review of the literature, showing in tabular form the effects of orchard pesticides on beneficial species.

Observations on predation of eggs of Hylemya brassicae (Bouché) were made from the Belleville laboratory from 1953 to 1955 as part of a general study of the biotic agents that act against the maggots that attack cruciferous crops. In biological control programs more attention has been given to parasites than to predators. Predation is more difficult to observe and to evaluate and, unlike parasitization, cannot be even roughly appraised by the collection and examination of hosts. As a group, predators are less specific in their food requirements and less regular in their habits than parasites and consequently do not lend themselves so readily to manipulation for biological control purposes. Predators used with success in biological control have had a high degree of specificity to their prey. Non-specific predators may, however, in the presence of large numbers of suitable hosts on which to feed, be important factors in reducing populations of noxious insects. Predation on eggs of H. brassicae is an example.

In view of the background of information on Bacillus popilliae Dutky (Beard, 1945) and the reported success of this bacterium in reducing populations of Popillia japonica Newm. (White and McCabe, 1950) and in view of the discovery of a similar bacterium attacking Odontria grubs in New Zealand (Dumbleton, 1945), a survey of microparasites and their possible pathogenicity in scarabaeid larvae was undertaken in Australia as a project supported by a Fulbright award.

The fallowing records represent a supplement to my former publication “Holarctic Elements among the Ichneumoninae of Maine” (Jour. Wash. Acad. Science 43. May, 1953, p. 148-50). They are based mainly on material obtained by the Northern Insect Survey, which is a co-operative project of the Canada Department of Agriculture and the Defence Research Board, Canada Department of National Defence.

In July, 1952, at Mount Pearl, Newfoundland, larvae were found boring into the trunk of an injured balsam poplar, Populus balsamifera L. In June, 1953, six moths emerged from sections of the injured trunk placed in a cage in an insectary.

Dr. T. N. Freeman (in litt.), Entomology Division, Ottawa, who determined the moth as Pyranthrene tabaniformis Rott. (vespiformis Westwood), stated that this was probably the first record of this European species in North America. This was confirmed by Mr. Kelvin Dorward (in litt.), Economic Insect Survey Section, United States Department of Agriculture, Washington, D.C.

During the past few years the pine needle scale, Phenacaspis pinifoliae (Fitch), has severely injured ponderosa pine, Engelmann spruce, and other evergreens in the Okanagan Valley of British Columbia. The home owner is most concerned because this insect is capable of ruining the appearance of evergreens on his property. Infestations may be severe on trees growing in submarginal forest areas.

Field experiments were conducted in the South Okanagan Valley in 1955 to determine whether lime-sulphur, malathion, or Diazinon (0,0-diethyl-0-[2-isopropyl-4-methyl-pyrimidyl (6)] thiophosphate) would control the scale on ponderosa pine trees.

It has long been known that the juices of the digestive tracts of lepidopterous larvae initiate action within the micro eggs of tachinid parasites that results in hatching (Severin et al., 1915). The etfect of the alkalinity of the digestive juices of larvae of the European corn borer, Pyrausta nubilalis (Hbn.), on hatching of eggs of Aplomya caesar (Ald.) was mentioned in an earlier paper (Wishart, 1945). More detailed work has revealed more clearly the critical nature of this relationship.