. Black grain-stem sawfly of Europe in the United States. Black grain-stem sawfly; Agricultural pests; Agricultural pests. BLACK GEAI^-STEM SAWFLY. These records probably indicate only approximately the present distribution (fig. 1) of the species. A more extended investigation will be necessary to establish the exact limits. The records are sufficient to establish a probability that it already occurs over the greater part of Virginia, Maryland, Pennsylvania, New Jersey, and Delaware, and it is possible that West Virginia, eastern Ohio, southern Xew York, and even some of the Xew England State
. Black grain-stem sawfly of Europe in the United States. Black grain-stem sawfly; Agricultural pests; Agricultural pests. BLACK GEAI^-STEM SAWFLY. These records probably indicate only approximately the present distribution (fig. 1) of the species. A more extended investigation will be necessary to establish the exact limits. The records are sufficient to establish a probability that it already occurs over the greater part of Virginia, Maryland, Pennsylvania, New Jersey, and Delaware, and it is possible that West Virginia, eastern Ohio, southern Xew York, and even some of the Xew England States may already be included within its range. PROBABLE FUTURE DISTRIBUTION IN AMERICA. Judging by its wide distribution in the Old World, as well as by the character of localities already included within its range in this country, including both tidewater and mountain districts, there seems little reason to doubt that the species will eventually spread over all the wheat- growing sections of the eastern and central United States. Whether it will accommodate itself to the arid and semiarid wheat- growing districts of the West is matter for specu- lation. The average pre- cipitation of this region does not differ greatly from that of southern Russia, where the species seems to be at its worst. The mean temperatures of the two regions probably are not widely differ- ent. It seems possible, therefore, that unless some other climatic or physical factor intervenes, the species may spread eventually from coast to coast. That it will spread northward into Canada may be doubted, since in Europe, although recorded from Sweden, it seems not to occur generally in the colder northern portion. FOOD PLANTS. FOOD PLANTS IN EUROPE. In European literature, with one exception, the records of food plants of Trachelus tabidus are by Eussian entomologists. Endow (43), in speaking of Cephus satyrus Panzer, C. nigrinus Thomson, G. pallipes Klug, C. arundinis Giraud, and C. tabidus Fabricius, makes the g
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