Saskatchewan had periodic outbreaks of grasshoppers long before the arrival of settlers. With the advent of agriculture these insects threatened the production of cereal and forage crops and necessitated the implementation of extensive control procedures. The effectiveness of control could be enhanced if farmers and government agencies were alerted and informed of the probable intensity and area of outbreak in the coming year. This lead to the initiation of forecasting the expected outbreaks, first, by questioning local persons as to the density, egg laying activities, and damage caused by local grasshopper populations and, secondly, by the inauguration of a special survey system of assessing abundance. Current populations of grasshopper adults or eggs were counted in all arable land areas of the province and rated in four categories of potential outbreak or hazard. The mapping of such ratings in their respective locations resulted in the production of a forecast map which indicated areas of probable light, moderate, severe, or very severe outbreak the following year. In Saskatchewan such maps have been produced annually since 1931 and are reproduced here. They represent the changing scene of grasshopper abundance in the past 36 years and have been accepted by agriculturists as a standard reference to be considered for sound agricultural production in the province.

The North American Aegeriidae are revised on the basis of the study of late-instar larvae of about 60 species. These species represent 20 genera in five tribes in two subfamilies: Bembeciini, Zenodoxini, Aegeriini and Melittiini in Zenodoxinae and Synanthedontini in Synanthedontinae. The presently recognized genera, Ramosia Engelhardt, Conopia Hübner and Thamnosphecia Spuler are reduced to synonyms of Synanthedon Hübner. Three new genera are defined by larval characters but are referred to only as Genera I, II and III. Larval characters for most of the species are discussed and illustrated; keys to species, genera and tribes are provided. Tribes, genera and most species are arranged in the text as nearly as possible according to their phylogenetic relationships as suggested by the larvae.

The 29 species and three subspecies comprising the imbecillus and rufus groups of the genus Philodromus in North America are described or redescribed, keyed, and illustrated. The imbecillus group contains six species, of which P. psaronius is described as new and the female of P. undarum Barnes is described for the first time. The rufus group contains 23 species and three subspecies, of which P. cubanus, P. distans, P. schicki, and P. bimuricatus are described as new-species, and P. rufus quartus as a new subspecies. P. inaequipes Banks, 1900 is proposed as a new synonym of P. minutus Banks, 1892, and P. michiganensis Levi, 1951 as a new synonym of P. peninsulanus Gertsch, 1934. P. mediocris Gertsch and P. minutus Banks are raised from synonymy, and P. pacificus Banks is raised from synonymy and made a subspecies of P. rufus Walckenaer.

The Sminthuridae, which comprises the largest of the two world-wide families in the suborder Symphypleona, contains 31 genera. Four of these, Collophora, Bothriovulsus, Vesicephalus, and Temeritas are described as new. This study was undertaken mainly to more accurately ascertain relationships within the family. As a result four subfamilies, the Sminthuridinae, the Katianninae, the Dicyrtominae, and the Sminthurinae, are recognized. Of these, the Sminthuridinae seems to have been the first group to become established and the Sminthurinae was relatively the more recent group. The material has been analyzed for indications as to probable age of the units that have been called genera and the place of origin. It seems likely that the generic units existed before the close of the Cretaceous and that the group originated in the north.

Myzocallis Passerini as here understood consists of the following 30 species: agrifolicola Richards, asclepiadis (Monell), bella (Walsh), borneri Stroyan, carpini (Koch), castanicola Baker, coryli (Goeze), discolor (Monell), elliotti Boudreaux and Tissot, ephemerata Richards, exultans Boudreaux and Tissot, frisoni Boudreaux and Tissot, glandulosa Hille Ris Lambers, granovskyi Boudreaux and Tissot, kuricola (Matsumura), longirostris Richards, longiunguis Boudreaux and Tissot, melanocera Boudreaux and Tissot, meridionalis Granovsky, mimica Richards, multisetis Boudreaux and Tissot, myricae (Kaltenbach), occulta Richards, pepperi Boudreaux and Tissot, picta (Ferrari), punctata (Monell), rostropunctata Richards, spinosa Boudreaux and Tissot, tuberculata Richards, walshii (Monell). A key and notes on the distribution and relationships of each species are given. A host index has been compiled.