In July of this year, Dr. E. A. Scott of Galena, Md., called the attention of the writer to a number of fine trees in his small town, all of which had been grown by him from _J. sieboldiana_ seed obtained from a tree nearby and "every one" of which was bearing "butternuts," as he and his neighbors call them. The American butternut does not occur in that part of Maryland which is on the upper end of the Chesapeake Peninsula, probably 10 miles from Chesapeake Bay. Both black and Persian walnut trees are very common in that region. The tree which bore the original seed is a typical Japanese walnut. It stands at the end of a row of Persian walnut trees along the driveway of a private country lane. There are several black walnut trees, perhaps 500 yards to the southwest, but no butternuts for many miles. As the Persian and Japanese walnuts blossom at about the same time and the black walnut considerably later, it would seem altogether probable that if any cross had taken place it would have been Japanese x Persian, rather than Japanese x black. The chances of a Japanese x butternut cross would have been so remote as to be altogether improbable. Many years ago, Judge F. P. Andrus of Almont, Mich., planted one tree each of Persian and Japanese walnuts in his dooryard. Both soon came into bearing. Squirrels planted nuts in the ground and presently the yard was filled with offspring, the majority of which were of the type now called butterjaps. The trees were extremely vigorous but the nuts were of so little value that all were finally cut down. Butternut trees are common in Michigan and butternut pollen may have been responsible for these crosses but circumstantially the evidence pointed much more strongly to Japanese x Persian crosses than to Japanese x butternut crosses. Other cases of these sorts might be cited, but the evidence which the writer has been able to bring together up to the present month, September, 1933, strongly indicates that butterjaps may be due to either an actual cross with a Persian or black walnut and possibly with butternut or to reversion to a parent oriental type. So far, it has been out of the question to hazard a reasonably safe assumption as to the staminate parent of all particular crosses by merely studying the botanical characteristics of the butterjap offspring. Several years ago Mr. Bixby planted a number of butterjap seed nuts, hoping that under the Mendelian law, the characteristics of the two parents would segregate themselves. The trunk and bark of some of the trees resembled black walnut quite distinctly, while none resembled the butternut. So far as is known to the writer, none of the trees have yet fruited. One of the several butterjap trees in Galena, Md., previously referred to, produced nuts rather more like black walnuts than butternuts. These two instances therefore, would suggest Japanese x black walnut parentage. Black Walnut Root Toxicity