Field workers are frequently faced with the necessity of making some sort of randomization. Thus randomization is today one of the conditions of trials in plots of, say, fertilizers or insecticides. Again, randomization is often attempted in sampling work, as when the number of insects in a plot or a field is to be ascertained from an incomplete examination; generally, when not attempted, it is by omission on the part of the investigator.

In classifying several collections of Mycetophilidae I have found six species which appear to be new. In addition I wish to report two interesting variations in wing venation which I observed.

Odynerus dorsalis, one of the largest of North American Eumenine wasps, may be recognized by the following characters.

Clypeus of female about one and one-third times as wide as long, the straight apical margin about one-fourth of the grearest width, with slight, blunt edges, the surface flattened medially and with scattering, medium-sized punctures; of male, slightly wider than long, the apical margin very slightly curved inward or almost straight, with the edges more prominent and sharper than in the female, the surface flattened medially and much more sparsely punctate than in the female.

In several small collections of myriopods recently made in North Carolina, and chiefly in the Duke Forest at Durham, by Mrs. Nelle Bevel Causey, and by her transmitted to me for identification, occur representatives of the species listed below. The purpose of the present paper is primarily to diagnose the several new forms represented; bur because of the interest of some of the other records it seems desirable to give the complete list here as supplementary to the catalogue of forms previously known from the region. The types of the new species are retained in the author's collection.

Since the publication of my revision of the North American species of this genus, the food-plants of the larvae of several species, at the time unknown, have been ascertained. The recording of these, together with a few other notes that have been made from time to time in the course of identification work, form the basis of the present paper.