Earlier in this volume (pp. 27–30), the writer has given an account of an eelworm obtained from a diseased potato tuber, possessing a mouth stylet with six basal swellings, an œsophagus without a muscular bulb such as occurs in Tylenchus and Aphelenchus, a vulva much more posterior in position than in the two genera just mentioned and a uterus without a post-vulvar diverticulum. On these characters the worms were placed in a new genus, Hexatylus.