The annual apple production of the world has increased immensely during the last two decades and parallelled with this there has been an increase in the number and complexity of chemical treatments to combat the various pests attacking this fruit. Spraying is now an accepted, though not welcome, practice and it is becoming increasingly evident that the desired control can not be attained at this time through the use of chemicals alone. Arthropod pests "resistant" to chemicals have been observed in numerous instances. Suppression of one pest only to allow another to increase is a common result of disturbing nature's natural balance.

In southwestern Quebec, eight species of grasshopper (Melanoplus femurrubrum, M. bivittatus, M. borealis, Orphulella specicosa, Chorthippus curtipennis, Encoptolophus sordidus, Chortophaga viridifasciata and Metrioptera roeseli) were studied during 1962, in relation to the following parasites: Mermis nigrescens (Nematoda), Eutrombidium trigonum (Acarina) and Sarcophagidae (Diptera). Mermis parasitism, in the situation studied, made little contribution to controlling the Acridid grasshopper populations in nature, with the probable regulation of nymphs of M. femurrubrum. In M. roeseli (Tettigoniidae), however, parasitism by this species appeared to have restricted both abundance of nymphs and adults and spatial distribution.

Insects like so many other living forms are susceptible to the infectious agents called viruses. Four types of insect viruses are recognized and these are: the nuclear polyhedroses (Borrelinavirus), the cytoplasmic polyhedroses (Smithiavirus), the granuloses (Bergoldiavirus), and non-inclusion viruses (Moratorvirus). Nuclear polyhedrosis viruses are rod-shaped, about 200 to 400 mμ in length and 20 to 70 mμ in diameter (Bergold, 1958). The virus particles are occluded by protein that crystallizes to form the polyhedral inclusion bodies which may range in size from 1.0μ to 10.0μ. Particles and inclusion bodies are formed in the nuclei of susceptible cells.

The balsam woolly aphid, Adelges piceae (Ratz.), is an introduced pest of European origin. It was discovered in Maine and New Hampshire in 1908, in Nova Scotia in 1929, and in Newfoundland in 1949 (Balch, 1952). True firs, Abies spp., are the only hosts of the aphid which causes severe damage to balsam fir, A. balsamea (L.) Mill., the predominant fir species in the Atlantic Provinces. Severe damage is caused by high numbers of aphids feeding in the crowns and on the stems of trees. In Newfoundland, rapid deterioration of tree crowns predominates; stem attack occurs infrequently and in widely dispersed spots (Carroll and Bryant, 1960). The infested area in the Province bas increased from 300 square miles in 1949 to over 3500 square miles in 1962.

Tyrosine, DOPA, DOPamine and N-acetyl DOPamine have been identified as the only phenolic substances occurring in the eggs or the house cricket, Acheta domesticus (L.). This is the first report or 2-diphenols in insect eggs known to the author. The quantitative variation and histochemical location of these substances indicate that they are involved in the formation of the serosal cuticle. N-acetyl DOPamine is probably the precursor of the quinone which tans the serosal epicuticle at the end or water absorption. Free DOPamine has been identified as the only free phenol in the extra embryonic fluid. The chemical identification and estimation of these aminophenols have involved some techniques that have not previously been applied to the study of tyrosine metabolites in insects.

The infestation of Pinus species in Ontario by species of Conophthorus Hopkins has been recognized for some time. Damage to the cones and shoots of eastern white pine, Pinus strobus Lamb., by Conophthorus coniperda (Schwarz) was noticed about 1884 (Harrington 1902a). Similar damage to red pine, P. resinosa Ait., due to C. resinosae Hopkins was reported by Harrington (1902a) to have been discovered several years later in 1887. Thomas and Lindquist (1956) and Herdy and Thomas (1961) have reported that shoots of jack pine, P. banksiana Lamb., are infested by Conophthorus species. The mining of Scots pine shoots, P. sylvestris Lamb., has also been mentioned by Thomas and Lindquist (1956), although the presence of Conophthorus species on this tree species does not seem to be extensive.

The capacity of some populations of insects to tolerate quantities of poisons which are far in excess of the quantities which are required to eliminate populations of their forebears has been called "tolerance" and "resistance". The difference between these two terms is one of degree. Low levels of resistance or tolerance in insects has been called "vigour tolerance" when it shows itself as a wide spectrum effect against a number of pressures. There exists a considerable controversy about its existence. Resistance in a noxious species poses serious economic problems in the control of that species. [...]

Factors responsible for variable results in small chamber fumigation tests were studied to develop a reliable and sensitive method for detecting susceptibility differences between insect strains. Quart Mason jars; weighed fumigant-filled glass capillary tubes; absorbent paper; and screen cages attached under jar lids and charged with insects through readily sealed openings constituted the apparatus selected. At room temperature a two-hour evaporation period, five-hour exposure period and 14- to 20-day post-exposure period proved best. The effects of day-to-day variability were minimized by testing each material along with a standard and making comparisons based on susceptibility indices. [...]

Recent studies on population ecology in Canada have through the life table approach revealed in part some of the processes responsible for insect outbreaks (Morris, 1963a.; LeRoux et al., 1963), and through the components approaeh (Holling, 1963; 1964) explained in part the operation of some of these processes. These studies, however, are lacking in detailed information on the trophic dynamic aspect (Lindeman, 1942) of the processes and components reported for insects investigated. [...]

During its taxonomic history, the family Pyrgomorphidae has had various names: 'Conophori' (Audinet-Serville, 1838, partim), 'Poeciloceridae' (Burmeister, 1840, partim; the correct spelling should be 'Poekiloceridae'), 'Phymatidae' (Burmeister, 1. c.; the correct spelling should be 'Phymateidae' as given by Scudder, 1868), 'Pyrogomorphinae' by later authors (Bolivar, 1884; McNeill, 1896; Bruner, 1900; Rehn 1904; 1907; and others). [...]