Sweetman (1940) suggested that unfavourable spring weather is probably the most important natural check for the forest tent caterpillar, Malacosonza disstria Hbn. He observed that warm weather in April or early May that induces hatching, followed by a week or more of cool weather, frequently destroys the caterpillars. Blackman (1918), Tomlinson (1938), and Hodson (1941) have reported similar observations.

During a study of the effects of spray chemicals on the arthropod communities of peach orchards in the Niagara Peninsula, Ontario, begun in 1946, Stethorus punctillum Weise was found to be one of the more important predators of tetranychid mites. An investigation of its biology was undertaken in 1949 and continued through 1952. This paper presents chiefly the life-history, behaviour, and ecological aspects.

In working on the biology of Hoplitis producta (Cress.) and going through a large number of nests of that species, one nest was discovered which was quite distinct from the others. At first, it was thought that this nest was perhaps the nest of another species of Hoplitis; however, the subsequent rearing of the bees and their identification has shown the nest to belong to Heriades (Neotrypetes) variolosus variolosus (Cresson). This is the first record of the nesting habit of any member of the subgenus Neotrypetes, and while the record is far from complete, it seems that for sake of a more complete picture on the nesting habits of the Megachilidae that it be reported at the time. Rau (1) has recorded the emergence of two individuals of Heriades (Physostetha) carinata Cresson from a hollowed out stem of sumach, but gave no details on the nest construction.

This description is based on an examination of 25 larvae of Hylobius radicis Buch. recovered from the damaged root-collars of dead and dying Scots pine, Pinus sylvestris L., in the vicinity of Angus, Ontario. Since larvae of at least one species of the genus Pissodes (P. approximatus Hopk.) may be found in the same trees, I am also taking this opportunity to compare the external structures of the larva of H. rardicis with those of the genus Pissodes (see Böving, 1929; Anderson, 1947). Where possible, and particularly in the description of the head capsule and mouth parts, the terminology used is that of Anderson.

The life histories of many of the Geometridae are not well known; those of a few economic species in the Ennominae have been worked out but many more remain to be studied. Life-history notes on the following seven species are presented: Semiothisa granitata Gn., S. sexmaculata Pack., Eufidonia discospilata Wlk., Melanolophia canadaria Gn., Campaea perlata Gn., Selenia alciphearia Wlk., and Caripeta divisata Wlk. The larvae of all these have been described; those of Selenia and Campaea were described by Dyar (1899 and 1903) and the remainder by McGuffin (1943a, 1943b, 1944, 1945, and 1947).

Black, uniformly dark brown- or grey-pollinose. Thorax obscurely quadrivittate. Legs short-haired. Wings milk-white in both sexes.

Head black; frons and occiput, viewed from above, velvety with dark-brown tinge; bristles and hairs fine, black, the former about as long as third antennal segment less style. Antenna black, slightly shorter than head; style about half as long as third segment. Palpus and proboscis black.

During the past spring and summer glass barrier traps have been used as a means of sampling the flying populations of an ambrosia beetle, Trypodendron sp., and other scolytid beetles. The “window” trap has functioned well enough to warrant its brief description. A piece of window glass (2 × 2 ft.) is set in a three-sided wooden frame from which a sheet metal trough is hung. The trough is filled with fuel oil or water to which a wetting agent is added. Screened outlets provide for drainage of excess rain water in the laner case and when oil is present an inverted “L” tube drains this water from beneath the oil. Insects are collected by removing the trough and pouring its contents through a strainer. Traps are hung from various types of pole framework depending on their location, and guy wires are used to keep them from swinging.