The satin moth, Stilpnotia salicis (L.), has been a pest of shade trees in the Maritime Provinces for about 25 years. Surveys of its distribution were started by the Division of Plant Protection (9) immediately following the discovery of this introduced species in 1930 and later carried out annually by members of the Fredericton Laboratory and the sub-laboratories at Debert, N.S., and Corner Brook, Newfoundland. The surveys have been accompanied by periodic collections and rearings, but only the larger and more representative of these are discussed in the present paper.

Dyar (1913) listed Diathrausta reconditalis (Walker) as a “form” of the South American D. nerinalis (Walker) and described as new the “form” harlequinalis from Arizona. From the context it is evident that in that paper Dyar used “form” as equivalent to geographic race, and the form names he proposed there can accordingly be treated as valid trinomina. Haimbach (1915), apparently in ignorance of Dyar's paper, described Diathrausta montana from Colorado. This was sunk by Barnes and McDunnough (1917) as a synonym of harlequinalis. Barnes and McDunnough listed harlequinalis as a geographical race of reconditalis, but did not follow Dyar in uniting these with nerinalis.

Two, or possibly three, types of stimuli that may influence host selection by entomophagous insects are produced by movements of the host or the prey. Movement may provide visual or tactile stimuli. Vibration caused by host movement may stimulate some species.

Tactile stimuli are produced by a host if it moves when touched by a parasite and are usually provided by a host that is enclosed in a case or a cocoon. Ullyert (1936), working with Dahlbominus fuscipennis (Zett.), and Williams (1951) and Thorpe and Jones (1937), working with Idechthis canescens (Grav.), found tactile stimuli an important factor in host selection, but Simmonds (1943) and Thompson and Parker (1927) concluded it was of little importance in I. canescens and Melittobia acasta Walk. respectively. Movement of potential prey upon contact stimulates attack by foraging ants (Vowels, 1955). Tactile stimuli produced by movement of the host may indicate an unsuitable host to the egg parasite Trichogramma evanescens Westw. (Salt, 1938).

The hemlock looper, Lambdina fiscellaria fiscellaria (Guen.), has been an important forest pest in Newfoundland for many years. Outbreaks have been reported from widely separated parts of the Island and in most cases the mortality of balsam fir, Abies balsamea (L.) Mill, has been high.

An investigation of the biology of the insect was commenced in 1950 at Lake St. George where two separate infestations had appeared in 1949. These infestations died out in 1951 and only limited information was obtained on some aspects of the investigation. As there is little prospect of continuing field studies in the near future, the results to date are being reported.

Natural and artificial reforestation, which basically depend on an abundance of sound seed, are adversely affected when insects destroy large numbers of cones, seeds, and cone-bearing shoots. Other factors, such as unfavourable weather, incomplete seed development, and damage by birds and mammals also reduce seed production, but they are rarely of such widespread importance as insects, whose damage often results in the failure of seed crops over large areas. Cone and seed insects sometimes restrict the natural regeneration of trees for a few years at a time, as, for example, in conifers on the Pacific coast (16), loblolly pines in Virginia (13), and oak in Michigan (5), but they become particularly important when the seeds they destroy are required for use in artificial reforestation. The future success of much reforestation, which is inclining more and more toward the use of seed obtained from trees cultivated especially for that purpose, may largely depend on a thorough understanding of cone and seed insects and their effect on seed production.

Coenosia tigrina (F.) was first observed in Canada in 1943 at Ottawa by Mr. A. R. Brooks of the Entomology Division (Mr. G. E. Shewell, Entomology Division, Ottawa, personal communication). By 1917 the insect had been collected as far west as Guelph, Ontario. It was first recorded from the province of Quebec in 1951 by Perron and Lafrance (1952), who observed it preying on adults of Hylemya antiqua (Mg.) in rearing cages at St. Jean. Later observations and surveys by these workers indicated the predator to be very abundant in southwestern Quebec. More recently Mr. F. M. Cannon (personal communication), Field Crop Insect Section, Science Service Laboratory, Charlottetown, Prince Edward Island, and Mr. L. A. Miller (personal communication), Entomology Laboratory, Chatham, Ont., reported C. tigrina to be present as far east as Charlottetown and as far west as Chatham.