The chordotonal organs of insects and especially those of the Acrididae are well known. Slifer (1936) lists 76 scoloparia which are distrilluted throughout the body of Melanoplus differentialis. Although the sense organs of Melanoplus mexicanus described in this study are, in general, similar to thnse found by Slifer, her summary account would seem to warrant a more detaited consideration of their structure.

The organ of Johnston in the second segment of the antenna is included because of its structural similarity to the chordotonal organs, although it is usually considered to have a special sensory functinn distinct from that of the chordotonal type.

During the past 25 years the wheat stem sawfly, Cephus cinctus Nort., has become one of the most destructive pests of wheat in the Prairie Provinces. Annual losses in the wheat-growing area of Saskatchewan have been estimated as high as 17 million bushels (King and McDonald, 1944). There are, however, several native parasites of this pest, and of these Bracon cephi (Gahan) [Microbracon cephi Gahan] is the most important. In some areas this parasite has been very effective in reducing severe sawfly infestations.

The problem of sample size usually confronts the research worker in the initial stages of an investigation. Many short methods have been used for determining sample size such as extracting the square root of the number of boxes or taking a 10 percent sample. While these techniques are easy to use nevertheless they are not based upon a statistical evaluation of the experiment. Sample size in an experiment is often dictated by the amount of time, money and labor available but even under such conditions it is possible to evaluate the precision of the experiment when the number of replications is dictated by necessity.

The W. S. Blatchley collection of Coleoptera, now at Purdue University, Lafayette, Indiana, contains thirteen primary types of Hydradephaga described by Blatchley. Some of the species represented have not been recognized by subsequent workers, while others have been synonymized without the original types having been seen. The following notes and comments therefore seem pertinent, and may prove of value to others engaged in the study of this group of insects.

Almost all of the members of the subfamily Ethopolyinae occur in western North America, a few Pacific islands, the Orient and Europe, but only one established species had been known from North America east of the Rocky Mountains. This widespread and very common form, Bothropolys multidentatus (Newport), ranges throughout the East as far west as Missouri. The present new species is therefore of special interest in that it is the second endemic member of the subfamily to he recorded from east of the Rockies. The only other members of Zygethopolys, a genus closely allied to Bothropolys, are known only from Alaska, British Columbia, and thk state of Washington.